With the escalating global emphasis on environmental conservation and sustainable development,enhancing the service quality and durability of road surfaces and facilitating the green development of highways have comma...With the escalating global emphasis on environmental conservation and sustainable development,enhancing the service quality and durability of road surfaces and facilitating the green development of highways have commanded considerable attention.Bio-based polyurethane,on account of its remarkable physical and chemical properties,green,sustainable and renewable capacity,as well as its structural design capabilities,has drawn widespread attention and numerous studies have been carried out.It has gradually started to substitute traditional petroleum-based polyurethane materials in road engineering.Nevertheless,the application of bio-based polyurethane materials in road engineering remains in the exploratory phase.To stimulate the application research of bio-based polyurethane materials in road engineering and offer additional research directions,this paper reviews the research advancements of bio-based polyurethane materials and their applications in road engineering.The fundamental classification of bio-based polyurethane is introduced.The characteristics and challenges associated with various preparation methods for bio-based polyurethane are described.The influence of bio-based polyurethane on road engineering materials are analyzed.The evaluation indicators of bio-based polyurethane within the life cycle of road engineering are investigated.Finally,the development tendency towards in road engineering applications are forecasted.This paper provides a reference for the study of bio-based polyurethane materials in road engineering applications.展开更多
In this work, a series of high performance bio-based polyurethanes（bio-PUs） were synthesized from polylactide（PLA）-based diols, different diisocyanates（TDI, MDI, HDI, IPDI） and chain extender 1,4-butanediol, in ...In this work, a series of high performance bio-based polyurethanes（bio-PUs） were synthesized from polylactide（PLA）-based diols, different diisocyanates（TDI, MDI, HDI, IPDI） and chain extender 1,4-butanediol, in which different soft and hard segments are used to adjust their transition temperatures and mechanical properties. Poly（lactide-co-caprolactone）copolymer diols（co-PLAols） instead of PLA diols as the soft segment improved the thermal stability and mechanical properties of the synthesized bio-PUs. Among them, MDI-based bio-PUs have the highest T_g（43.8 °C）, tensile strength（23.5 MPa） and modulus（380.8 MPa）, while HDI-based bio-PUs have the lowest T_g（21.4 °C） and highest elongation at break（580%）. Especially, the bio-PUs synthesized from co-PLAols and MDI demonstrate better mechanical properties,closed to petroleum-based commodities. Furthermore, the obtained bio-PUs display good shape memory properties at body temperature and cytocompatibility. Therefore, these bio-PUs are promising for applications in biomedical fields.展开更多
Elastic bio-based waterproof and breathable membranes(EBWBMs) allow the passage of water vapor effectively and resist the penetration of liquid water,making it ideal for use under extreme conditions.In this study,we u...Elastic bio-based waterproof and breathable membranes(EBWBMs) allow the passage of water vapor effectively and resist the penetration of liquid water,making it ideal for use under extreme conditions.In this study,we used a facile strategy to design the bio-based polyurethane(PU) nanofibrous membranes with the nanoscale porous structure to provide the membranes with high waterproof and breathable performances.The optimization of nanofibrous membrane formation was accomplished by controlling the relative ambient humidity to modulate the cooperating effects of charge dissipation and non-solvent-induced phase separation.The obtained EBWBMs showed multiple functional properties,with a hydrostatic pressure of 86.41 kPa and a water vapor transmission(WVT) rate of 10.1 kg·m^(-2)·d^(-1).After 1 000 cycles of stretching at 40% strain,the EBWBMs retained over 59% of the original maximum stress and exhibited an ideal elasticity recovery ratio of 85%.Besides,even after 80% deformation,the EBWBMs still maintained a hydrostatic pressure of 30.65 kPa and a WVT rate of 13.6 kg·m^(-2)·d^(-1),suggesting that bio-based PU nanofibrous membranes could be used for protection under extreme conditions.展开更多
Through systematical experiment design, the physical blowing agent(PBA) mass loss of bio-based polyurethane rigid foam(PURF)in the foaming process was measured and calculated in this study, and different eco-friendly ...Through systematical experiment design, the physical blowing agent(PBA) mass loss of bio-based polyurethane rigid foam(PURF)in the foaming process was measured and calculated in this study, and different eco-friendly PBA mass losses were measured quantitatively for the first time. The core of the proposed method is to add water to replace the difference, and this method has a high fault tolerance rate for different foaming forms of foams. The method was proved to be stable and reliable through the standard deviations σ1and σ2for R1(ratio of the PBA mass loss to the material total mass except the PBA) and R2(ratio of the PBA mass loss to the PBA mass in the material total mass) in parallel experiments. It can be used to measure and calculate the actual PBA mass loss in the foaming process of both bio-based and petroleumbased PURF. The results show that the PBA mass loss in PURF with different PBA systems is controlled by its initial mass content of PBA in PU materials ω. The main way for PBA to dissipate into the air is evaporation/escape along the upper surface of foam. This study further reveals the mechanism of PBA mass loss: the evaporation/escape of PBA along the upper surface of foam is a typical diffusion behavior. Its spread power comes from the difference between the chemical potential of PBA in the interface layer and that in the outside air. For a certain PURF system, R1has approximately linear relationship with the initial mass content of PBA in PU materials ω, which can be expressed by the functional relationship R1= kω, where k is a variable related to PBA’s own attributes.展开更多
Given the increasing global demand for sustainablematerials and growing concerns over the depletion of petrochemical resources,we report the synthesis of an amorphous bio-derived polyester diol,and this diol was polym...Given the increasing global demand for sustainablematerials and growing concerns over the depletion of petrochemical resources,we report the synthesis of an amorphous bio-derived polyester diol,and this diol was polymerized with various isocyanates and butanediol,yielding a novel series of bio-based polyurethane elastomers(BPUEs).Notably,the prepared HDI-17% exhibited remarkable mechanical properties comparable to petroleum-based elastomers while demonstrating exceptional biodegradability.Specifically,the elastomer indicated an enzymatic degradation ratio of 82.0% within 20 days and a relative compost degradation ratio of up to 95.5% compared with lignin over 90 days.These results significantly surpass the degradation rates of other degradable PUs reported in the literature.Regarding the degradation mechanism,our findings indicated that enzymatic degradation primarily targeted the ester groups of soft segments,with the process occurring layer-by-layer from exterior to interior.Additionally,microphase separation significantly influenced the degradation rate.Notably,both the BPUEs and their degradation byproduct solution were found to be nonbiotoxicity,highlighting their potential for safe application within biological systems.Furthermore,the BPUEs exhibited remarkable 3D printability,allowing for the precise fabrication of complex devices.These results mark a significant step forward in sustainable materials,providing viable options for the applications of customizing degradable biomedical devices.展开更多
In this study,a facile method was employed to synthesize strong,yet highly elastic polyurethane-urea(PUU)with typical characteristics and 94% optical transmittance.Graphene platelets(GNPs)were prepared and modified vi...In this study,a facile method was employed to synthesize strong,yet highly elastic polyurethane-urea(PUU)with typical characteristics and 94% optical transmittance.Graphene platelets(GNPs)were prepared and modified via a scalable and eco-friendly mechanochemical approach.The produced GNPs is at 1.6-nm thickness with high electrical conductivity of~950 S/m.The structure-property relations of PUU/GNP nanocomposites were comprehensively investigated through morphology and mechanical properties measurements.The strong interface and high-density hydrogen bonds between modified GNPs(M-GNPs)and PUU significantly enhanced the mechanical properties of the PUU nanocomposite.The PUU composite showed 66.7%and 36.2%increments in tensile and impact strengths,respectively,at 0.2 wt% M-GNPs.The reversible hydrogen bond between M-GNPs and PUU endowed the nanocomposite with self-healing properties achieving 97.8% healing efficiency of the strength after 5 h at 120℃.This study demonstrates the importance of surface modification and provides a simple yet robust approach for preparing high-performance and functional PUU/graphene composites.展开更多
Azobenzene-based polymer actuators show great promise for photoactuation owing to their unique photoisomerization behavior and tailorable molecular programmability.However,conventional systems are limited by inadequat...Azobenzene-based polymer actuators show great promise for photoactuation owing to their unique photoisomerization behavior and tailorable molecular programmability.However,conventional systems are limited by inadequate mechanical robustness,self-healing,and recyclability,hindering their practical implementation.Herein,we present a high-performance azobenzene-functionalized polyurethane(AzoPU)elastomer actuator designed via molecular engineering of photoactive azobenzene moieties and dynamic disulfide bonds.AzoPU exhibits exceptional mechanical properties with retained performance after multiple reshaping cycles,enabled by well-engineered hard-soft segments and synergistic stress dissipation from weak covalent bonds/hierarchical hydrogen bonds.It achieves over 93%self-healing efficiency at room temperature owing to the synergistic interplay of disulfide bonds in the polymer backbone and intermolecular hydrogen bonds.Furthermore,it demonstrates remarkable light-triggered actuation behavior,achieving a phototropic bending angle exceeding 180°toward the light source within 45 s.To showcase its practical potential,proof-of-concept photoactuated devices with flower-,hook-,and gripper-like and local-orientation processed strip-shaped structures were fabricated,which exhibited rapid and reversible light-triggered deformation.This study proposes a novel strategy for the development of intelligent polymeric materials that integrate light responsiveness,self-healing,and recyclability,thus holding great promise for applications in flexible electronics,smart actuators,and sustainable functional materials.展开更多
Recent advancements in developing tannin-based non-isocyanate polyurethane(NIPU)resins have unlocked new possibilities for sustainable and eco-friendly wood adhesives.Unlike conventional polyurethane,NIPUs eliminate h...Recent advancements in developing tannin-based non-isocyanate polyurethane(NIPU)resins have unlocked new possibilities for sustainable and eco-friendly wood adhesives.Unlike conventional polyurethane,NIPUs eliminate hazardous isocyanates,offering safer alternatives for industrial applications.Tannin,a naturally occurring polyphenolic compound,plays a pivotal role in enhancing these resins’fire-resistance and super-hydrophobic properties.This review highlights key developments in synthesizing tannin-based NIPU,focusing on various polymerization techniques such as polyaddition,polycondensation,ring-opening polymerization,and rearrangement.These strategies contribute to improved mechanical strength,thermal stability,and resistance to water absorption.Recent studies demonstrate that tannin-based NIPU adhesives meet or exceed international internal bonding strength,elasticity,and durability standards.Their application in wood-based composites like oriented strand boards(OSB)has shown promising results,offering improved resistance to moisture and superior dimensional stability.Furthermore,the cross-linked polymer network,supported by chemical modifications like the introduction of fluoroalkyl groups,significantly enhances hydrophobicity and fire retardancy.Despite these advancements,challenges remain in terms of scalability,cost,and integration with existing manufacturing processes.Future research should focus on optimizing reaction conditions,improving raw material availability,and developing industrial-scale production methods.This review underscores the potential of tannin-based NIPU resins as a viable and sustainable alternative for various wood composite applications.展开更多
Epoxy resins are widely employed in wind turbine blades,drone rotors,and automotive interiors due to their excel-lent mechani-cal proper-ties and long service life.However,their insoluble and infusible cross-linked ne...Epoxy resins are widely employed in wind turbine blades,drone rotors,and automotive interiors due to their excel-lent mechani-cal proper-ties and long service life.However,their insoluble and infusible cross-linked networks pose a significant re-cycling challenge,particularly with the impending retirement of the first generation of wind turbine blades.In this work,we reported a fully bio-based epoxy Vitrimer(FEP)incorporat-ing a dual-dynamic covalent network design and systematically investigated the influence of the 1,5,7-triazabicyclo[4.4.0]dec-5-ene(TBD)catalyst on its curing kinetics,thermal/mechan-ical properties,dynamic exchange behavior,and degradation performance in a mild alkaline solution.Compared to conventional epoxy resins,FEP exhibited superior tensile strength and elongation at break at an optimal TBD concentration(2 wt%),achieving an excellent strength-toughness balance.The presence of TBD accelerated the exchange rates of both disulfide and ester bonds,endowing FEP with notable stress relaxation at elevated tempera-tures.Moreover,FEP demonstrated complete dissolution in 1 mol/L NaOH within 6 h at 25℃.These results underscored the exceptional strength,toughness,and recyclability of FEP,positioning it as a promising,environmentally friendly matrix resin for next-generation appli-cations in the new energy sector.展开更多
Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,whil...Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,while lignin-based alternatives exhibit insufficient photothermal conversion efficiency.Herein,we developed a novel strategy to enhance photothermal performance of lignin through sequential demethylation modification and Fe^(3+)complexation for constructing NIR light responsive SMPs.Dealkaline lignin(DL)was first demethylated using iodocyclohexane to produce demethylated lignin(DDL)with increased catechol content,which was then incorporated into polycaprolactone-based polyurethane synthesis followed by Fe^(3+)complexation.Results showed that DDL-Fe^(3+)complexes have significantly enhanced photothermal conversion performance,and the resulting PU-DDL+Fe^(3+)polyurethane with 0.5 wt%DDL content demonstrated a temperature increases of 39.8℃under 0.33 W·cm-2808 nm NIR irradiation.This excellent photothermal performance enables the shape-fixed PU-DDL+Fe^(3+)polyurethane to rapidly recover to its initial shape under NIR light irradiation.Additionally,PU-DDL+Fe^(3+)polyurethane exhibits good mechanical properties and biocompatibility,demonstrating significant biomedical application potential.展开更多
Polyurethane elastomers exhibit high dielectric constants owing to their polar groups,and can be used as energy storage capacitors.Energy storage depends not only on the dielectric constant but also on the dielectric ...Polyurethane elastomers exhibit high dielectric constants owing to their polar groups,and can be used as energy storage capacitors.Energy storage depends not only on the dielectric constant but also on the dielectric loss.However,the relationship between chain structure and dielectric properties is not yet clear.Ketal-containing crosslinked polyurethane elastomers were prepared using cyclic ketal diol as a chain extender.The effect of the soft segment length on the dielectric properties and energy storage was investigated.The cause of the change in the dipolar polarization with the soft segment length was analyzed.As the soft segment length increased,the hard-soft hydrogen bonding decreased,whereas the hard-hard hydrogen bonding increased.Under the action of an electric field,the polar bonds in the ketal-containing polyurethane elastomer overcome the hydrogen bonding between hard-soft segments to produce polarization;meanwhile,they also experience crankshaft motions to generate polarization.The former has a relatively high relaxation activation energy of approximately 10-20 k J·mol^(-1),resulting in a large dielectric loss.The latter has a relatively low relaxation activation energy,approximately 0.7-1.7 kJ·mol^(-1),leading to low dielectric loss.As a result,the dielectric constant showed a decreasing trend,and the dielectric loss gradually decreased.This study provides a theoretical foundation for improving the dielectric properties of polyurethane elastomers.展开更多
The structural design and performance characteristics of the diaphragm have a decisive impact on the safety and electrochemical performance of lithium-ion batteries(LIBs).However,traditional polyolefin diaphragms stil...The structural design and performance characteristics of the diaphragm have a decisive impact on the safety and electrochemical performance of lithium-ion batteries(LIBs).However,traditional polyolefin diaphragms still face challenges in simultaneously improving the ion transport efficiency and thermal stability.Here,we report an in situ dynamic lithium compensation strategy for manufacturing a biobased furan aramid/ceramic diaphragm(BAS)with higher thermal stability and ion transport efficiency.Specifically,exchangeable carboxyl groups(–COOH)are introduced into the bio-based furan aramid(BA)framework,which are in situ converted into–COOLi groups to form lithium ions(Li^(+))transport channels,achieving dynamic compensation of active Li^(+).The dual transmission system of ion exchange and physical pore channels synergistically enhances the ionic conductivity of BAS to 1.536 mS cm^(-1).The high polarity structure of the furan ring and the electrolyte have excellent compatibility,significantly reducing the solid–liquid interfacial energy,making BAS have extremely high electrolyte wettability(contact angle of 0°).The BA amide group forms a multi-scale bonding network with the nano-ceramics.The BAS prepared by the water-coating process exhibits excellent thermal stability(with a thermal shrinkage rate of less than 1%after 1 h at 150℃).The LiFePO_(4)|Li half-cell assembled with BAS shows a capacity retention rate of up to 91.7%after 280 cycles at 1C,with a Coulomb efficiency of 99%,demonstrating excellent cycling stability.This design and development based on bio-materials provides a new approach for high safety and high energy density battery systems.展开更多
The development of intrinsically conductive piezoresistive sensors with high strain tolerance has garnered significant interest.While elastomeric polymers exhibit excellent strain capabilities,their utility in sensing...The development of intrinsically conductive piezoresistive sensors with high strain tolerance has garnered significant interest.While elastomeric polymers exhibit excellent strain capabilities,their utility in sensing applications has been limited by inherent challenges such as high electrical resistivity,poor aging resistance,and interfacial incompatibility.To address these limitations,hydroxyl-terminated polybutadiene(HTPB)-based polyurethane was chemically modified with acetylferrocene-polyaniline conductive moieties to enhance charge transport properties.Remarkably,this covalent functionalization endowed the resulting ferrocene-polyaniline hybrid polyurethane(FPHP)with a conductivity of2.33 n A at 1 V bias while preserving piezoresistive functionality.The FPHP demonstrated exceptional mechanical-electrical performance,achieving 254% elongation at break with strain-dependent gauge factors of 7.28(0%-12.5% strain,R^(2)=0.9504)and 19.66(12.5%-35.0% strain,R^(2)=0.9929).Further characterization revealed a rapid 0.60 s response time and stability over 3500 strain-release cycles at compression strain,underscoring its durability under repetitive loading.The FPHP sensor was capable of monitoring various human movements and recognizing writing signals.These advances establish a materials design paradigm for fabricating flexible sensors that synergistically integrate high deformability,tunable sensitivity,and robust operational stability,positioning FPHP as a promising candidate for next-generation wearable electronics and soft robotics.展开更多
Pyrolysis technology has emerged as a promising method for converting waste polyurethane(WPU)from waste refrigerators into high-value chemicals.In this study,the copper(Cu)-assisted pyrolysis strategy was employed to ...Pyrolysis technology has emerged as a promising method for converting waste polyurethane(WPU)from waste refrigerators into high-value chemicals.In this study,the copper(Cu)-assisted pyrolysis strategy was employed to enhance the thermal degradation efficiency and product quality of WPU.Kinetic analysis revealed that the activation energy(E_(a)) of the Cu-assisted pyrolysis was 136.64 kJ·mol^(−1) and Cu-assisted pyrolysis was controlled by the combined processes of diffusion,nucleation and phase boundary reactions.Comprehensive product analysis,including gas chromatography–mass spectrometry and thermogravimetric Fourier transform infrared spectroscopy–mass spectrometry suggested that Cu promoted the cleavage of urethane bonds and accelerated the decarboxylation of isocyanates,increasing the yields of aniline and ethanol at lower temperatures.Meanwhile,Cu effectively suppressed the formation of halogenated and heterocyclic compounds by promoting the cleavage of C–X(X=Cl,F)bonds through electron transfer interactions.Thus,the E_(a) is decreased and the halogenated compounds is reduced.This work provides the theoretical basis for converting waste to high-valued products through co-pyrolysis techniques.展开更多
Airless tires are essential for enhancing the safety,reliability,and convenience of maintenance of electric bicycles.Polyurethane(PU)is considered a promising candidate for such applications owing to its versatile pro...Airless tires are essential for enhancing the safety,reliability,and convenience of maintenance of electric bicycles.Polyurethane(PU)is considered a promising candidate for such applications owing to its versatile properties.However,their use is limited by insufficient heat resistance and excessive dynamic heat generation under cyclic loading.In this study,star-shaped trifunctional polypropylene glycerol(PPG3)was incorporated into conventional poly(tetramethylene glycol)(PTMG)and 4,4'-methylenediphenyl diisocyanate(MDI)-based systems to construct microporous star-shaped casting polyurethanes(SCPU),with water serving as a green foaming agent.Unlike conventional small-molecule trifunctional crosslinkers that create junctions within hard segment domains,PPG3 introduces long flexible arms between the hard segments,anchoring the crosslinking points at its molecular core.The large steric hindrance of PPG3 effectively suppresses soft segment crystallization and lowers the degree of microphase separation,whereas the crosslinked network restricts chain mobility,thereby reducing dynamic heat generation.These structural features also enhance the heat resistance,yielding a softening temperature of 183℃,which is 30.9%higher than that of polyurethane without PPG3.When applied to airless tires by casting SCPU into rubber treads,the fabricated hybrid airless tires achieved a rolling distance of over 3000 km under a load of 65 kg at 25km/h without structural failure,satisfying practical performance requirements.This strategy offers a simple,solvent-free,and environmentally friendly process,underscoring the potential of SCPU for scalable production of high-performance airless tires.展开更多
Background:The development of materials for cardiovascular surgery that would improve the effectiveness of surgical interventions remains an important task.Surgical intervention during the implantation of vascular pro...Background:The development of materials for cardiovascular surgery that would improve the effectiveness of surgical interventions remains an important task.Surgical intervention during the implantation of vascular prostheses and stents,and the body’s reaction to artificial materials,could lead to chronic inflammation,a local increase in the concentration of proinflammatory factors,and stimulation of unwanted tissue growth.The introduction of nonsteroidal anti-inflammatory drugs into implantable devices could be used to obtain vascular implants that do not induce inflammation and do not induce neointimal tissue outgrowth.Methods:The scaffolds were made by electrospinning from mixtures of polyurethane(PU)with diclofenac(DF).The kinetics of DF release from the scaffolds composed of 3%PU/10%HSA/3%DMSO/DF and 3%PU/DF were studied.The biocompatibility and anti-inflammatory effects of the obtained scaffolds on human gingival fibroblasts and umbilical vein endothelial cells were studied.Results:Both types of scaffolds are characterized by fast DF release.The viability of cells cultured on scaffolds is 2 times worse than that of cells cultured on plastic.The level of the proinflammatory cytokine IL-6 in the culture medium of cells cultured on DF-containing scaffolds was lower than that of cells cultured on scaffolds without DF.Conclusion:The introduction of DF into scaffolds minimizes the inflammation caused by cell reactions to an artificial material.展开更多
This study aimed to systematically regulate the performance of 4D printing composites by investigating the synergistic effects of dicumyl peroxide(DCP)and maleic anhydride-grafted polyethylene(MAH-g-PE)on a poly(lacti...This study aimed to systematically regulate the performance of 4D printing composites by investigating the synergistic effects of dicumyl peroxide(DCP)and maleic anhydride-grafted polyethylene(MAH-g-PE)on a poly(lactic acid)/thermoplastic polyurethane(PLA/TPU)matrix.Specifically,using a 70 wt%/30 wt%PLA/TPU matrix and an L_(9)(3^(2))orthogonal design,composites were evaluated via morphology,shape memory,mechanical tests,and multi-criteria analysis.Moderate DCP enhanced crosslinking,improving storage modulus and thermal stability,while excessive DCP caused brittleness.Furthermore,MAH-g-PE effectively improved interfacial compatibility,and its synergy with DCP was dosage-dependent.Consequently,Sample 5 achieved optimal performance,exhibiting uniform fracture morphology,a shape fixation rate of98.8%with the fastest recovery,and balanced strength-ductility.Multi-criteria analysis identified elongation at break and recovery time as the top contributing factors,with consistent rankings validated by Spearman analysis(ρ=0.833,p<0.01).In summary,adjusting DCP and MAH-g-PE contents effectively modulates the crosslinking structure and interfacial properties of PLA/TPU composites,providing a viable strategy for developing high-performance,tunable 4D printing materials.展开更多
Developing green and efficient methods to acquire lignocellulose-based chemicals with high added value is beneficial for facilitating green chemistry and sustainable development.The goal of this study is to demonstrat...Developing green and efficient methods to acquire lignocellulose-based chemicals with high added value is beneficial for facilitating green chemistry and sustainable development.The goal of this study is to demonstrate that bio-based benzaldehyde,a noteworthy high-value chemical,is able to be directionally prepared from lignocellulosic biomass.This new control-lable transformation was materialized by uniting catalytic-pyrolysis of lignocellulose to toluene intermediate and catalytic oxidation of toluene intermediate to bio-based benzalde-hyde.This work also developed a highly active magnetic catalyst(CoFe_(2)O_(4)@Biochar(HTR)),achieving 77.1%benzaldehyde selectivity and 46.7%benzaldehyde yield using this catalyst.It was found that introducing the biochar carrier into the cobalt iron composite metal oxide cat-alyst enhanced hydroxyl radical formation and bio-based benzaldehyde synthesis.Based on catalyst characterizations and hydroxyl radical analysis,potential reaction mechanism for bio-based benzaldehyde synthesis was proposed.This strategy may provide a beneficial pathway for developing high-value bio-based chemical(benzaldehyde)using renewable lignocellulosic biomass.展开更多
Bio-based polyurethane foam has attracted increasing attentions due to eco-friendliness and fossil feedstock issues.However,the inherent flammability limits its application in different fields.Herein,we demonstrate a ...Bio-based polyurethane foam has attracted increasing attentions due to eco-friendliness and fossil feedstock issues.However,the inherent flammability limits its application in different fields.Herein,we demonstrate a green bio-based flame-retardant system to fabricate polyurethane foam composite with durable flame retardancy,smoke suppression,and thermal insulation property.In this system,the green bio-based polyol(VED)with good reactivity and compatibility plays a role of flame retardant and EG acts as a synergistic filler.As a result,the LOI value of foam composite increased to 30.5 vol.%and it achieved a V-0 rating in the UL-94 vertical burning test.Additionally,the peak heat release rate(pHRR)and the total smoke production(TSP)decreased by 66.1%and 63.4%,respectively.Furthermore,the foam composite maintained durable flame retardancy after accelerated thermal aging test,whose thermal-insulating property was maintained even after being treated in high-humidity environment with 85%R.H.for a week.This work provides a facile strategy for durable flame retardancy and long-term thermal insulation performance,and creates opportunities for the practical applications of bio-based foam composites.展开更多
In this study,acrylic acid was used as a neutralizer to prepare bio-based WPU with an interpenetrating polymer network structure by thermally induced free radical emulsion polymerization.The effects of the content of ...In this study,acrylic acid was used as a neutralizer to prepare bio-based WPU with an interpenetrating polymer network structure by thermally induced free radical emulsion polymerization.The effects of the content of acrylic acid on the properties of the resulting waterborne polyurethane-poly(acrylic acid)(WPU-PAA)dispersion and the films were systematically investigated.The results showed that the cross-linking density of the interpenetrating network polymers was increased and the interlocking structure of the soft and hard phase dislocations in the molecular segments of the double networks was tailored with increasing the content of acrylic acid,leading to enhancement of the mechanical properties and water resistance of WPU-PAA films.Notably,with the increase in content of acrylic acid,the tensile strength,Young’s modulus,and toughness of the WPU-PAA-110 film increased by 3 times,and 8 times,and 2.4 times compared with WPU-PAA-80,respectively.The WPU-PAA-100 film showed the best water resistance,and the water absorption rate at 96 h was only 3.27%.This work provided a new design scheme for constructing bio-based WPU materials with excellent properties.展开更多
基金supported by the Key R&D Project in Shaanxi Province(No.2024GX-YBXM-371)Shaanxi Qinchuangyuan Scientists+Engineers Team Construction Project(2025QCY-KXJ-141).
文摘With the escalating global emphasis on environmental conservation and sustainable development,enhancing the service quality and durability of road surfaces and facilitating the green development of highways have commanded considerable attention.Bio-based polyurethane,on account of its remarkable physical and chemical properties,green,sustainable and renewable capacity,as well as its structural design capabilities,has drawn widespread attention and numerous studies have been carried out.It has gradually started to substitute traditional petroleum-based polyurethane materials in road engineering.Nevertheless,the application of bio-based polyurethane materials in road engineering remains in the exploratory phase.To stimulate the application research of bio-based polyurethane materials in road engineering and offer additional research directions,this paper reviews the research advancements of bio-based polyurethane materials and their applications in road engineering.The fundamental classification of bio-based polyurethane is introduced.The characteristics and challenges associated with various preparation methods for bio-based polyurethane are described.The influence of bio-based polyurethane on road engineering materials are analyzed.The evaluation indicators of bio-based polyurethane within the life cycle of road engineering are investigated.Finally,the development tendency towards in road engineering applications are forecasted.This paper provides a reference for the study of bio-based polyurethane materials in road engineering applications.
基金financially supported by the National Natural Science Foundation of China(No.21404112)Ningbo Key Scientific and Technological Project(No.2014B10023)+2 种基金Ningbo Natural Science Foundation(No.2015A610016)Open Project of Key Laboratory of Marine Materials and Related Technologies(No.2016K07)Ningbo Science and Technology Innovation Team(No.2015B11003)
文摘In this work, a series of high performance bio-based polyurethanes（bio-PUs） were synthesized from polylactide（PLA）-based diols, different diisocyanates（TDI, MDI, HDI, IPDI） and chain extender 1,4-butanediol, in which different soft and hard segments are used to adjust their transition temperatures and mechanical properties. Poly（lactide-co-caprolactone）copolymer diols（co-PLAols） instead of PLA diols as the soft segment improved the thermal stability and mechanical properties of the synthesized bio-PUs. Among them, MDI-based bio-PUs have the highest T_g（43.8 °C）, tensile strength（23.5 MPa） and modulus（380.8 MPa）, while HDI-based bio-PUs have the lowest T_g（21.4 °C） and highest elongation at break（580%）. Especially, the bio-PUs synthesized from co-PLAols and MDI demonstrate better mechanical properties,closed to petroleum-based commodities. Furthermore, the obtained bio-PUs display good shape memory properties at body temperature and cytocompatibility. Therefore, these bio-PUs are promising for applications in biomedical fields.
基金National Key R&D Program of China(No.2021YFE0105100)Fok Ying-Tung Education Foundation,China(No.171065)Shanghai Rising-Star Program,China(No.20QA1400500)。
文摘Elastic bio-based waterproof and breathable membranes(EBWBMs) allow the passage of water vapor effectively and resist the penetration of liquid water,making it ideal for use under extreme conditions.In this study,we used a facile strategy to design the bio-based polyurethane(PU) nanofibrous membranes with the nanoscale porous structure to provide the membranes with high waterproof and breathable performances.The optimization of nanofibrous membrane formation was accomplished by controlling the relative ambient humidity to modulate the cooperating effects of charge dissipation and non-solvent-induced phase separation.The obtained EBWBMs showed multiple functional properties,with a hydrostatic pressure of 86.41 kPa and a water vapor transmission(WVT) rate of 10.1 kg·m^(-2)·d^(-1).After 1 000 cycles of stretching at 40% strain,the EBWBMs retained over 59% of the original maximum stress and exhibited an ideal elasticity recovery ratio of 85%.Besides,even after 80% deformation,the EBWBMs still maintained a hydrostatic pressure of 30.65 kPa and a WVT rate of 13.6 kg·m^(-2)·d^(-1),suggesting that bio-based PU nanofibrous membranes could be used for protection under extreme conditions.
文摘Through systematical experiment design, the physical blowing agent(PBA) mass loss of bio-based polyurethane rigid foam(PURF)in the foaming process was measured and calculated in this study, and different eco-friendly PBA mass losses were measured quantitatively for the first time. The core of the proposed method is to add water to replace the difference, and this method has a high fault tolerance rate for different foaming forms of foams. The method was proved to be stable and reliable through the standard deviations σ1and σ2for R1(ratio of the PBA mass loss to the material total mass except the PBA) and R2(ratio of the PBA mass loss to the PBA mass in the material total mass) in parallel experiments. It can be used to measure and calculate the actual PBA mass loss in the foaming process of both bio-based and petroleumbased PURF. The results show that the PBA mass loss in PURF with different PBA systems is controlled by its initial mass content of PBA in PU materials ω. The main way for PBA to dissipate into the air is evaporation/escape along the upper surface of foam. This study further reveals the mechanism of PBA mass loss: the evaporation/escape of PBA along the upper surface of foam is a typical diffusion behavior. Its spread power comes from the difference between the chemical potential of PBA in the interface layer and that in the outside air. For a certain PURF system, R1has approximately linear relationship with the initial mass content of PBA in PU materials ω, which can be expressed by the functional relationship R1= kω, where k is a variable related to PBA’s own attributes.
基金supported by the National Key R&D Program of China(2022YFB3704700)National Science Foundation for Young Scientists of China(51703007)+1 种基金National Natural Science Foundation of China(52341301)National Natural Science Foundation of China and Basic Science Center Program(51988102).
文摘Given the increasing global demand for sustainablematerials and growing concerns over the depletion of petrochemical resources,we report the synthesis of an amorphous bio-derived polyester diol,and this diol was polymerized with various isocyanates and butanediol,yielding a novel series of bio-based polyurethane elastomers(BPUEs).Notably,the prepared HDI-17% exhibited remarkable mechanical properties comparable to petroleum-based elastomers while demonstrating exceptional biodegradability.Specifically,the elastomer indicated an enzymatic degradation ratio of 82.0% within 20 days and a relative compost degradation ratio of up to 95.5% compared with lignin over 90 days.These results significantly surpass the degradation rates of other degradable PUs reported in the literature.Regarding the degradation mechanism,our findings indicated that enzymatic degradation primarily targeted the ester groups of soft segments,with the process occurring layer-by-layer from exterior to interior.Additionally,microphase separation significantly influenced the degradation rate.Notably,both the BPUEs and their degradation byproduct solution were found to be nonbiotoxicity,highlighting their potential for safe application within biological systems.Furthermore,the BPUEs exhibited remarkable 3D printability,allowing for the precise fabrication of complex devices.These results mark a significant step forward in sustainable materials,providing viable options for the applications of customizing degradable biomedical devices.
基金The National Natural Science Foundation of China(No.52173077)the Liaoning Provincial Department of Education Series Project(No.LJKZ0187)+1 种基金Natural Science Foundation of Liaoning Province(No.2023-MS-239)Liaoning BaiQianWan Talents Program(No.2021921081)。
文摘In this study,a facile method was employed to synthesize strong,yet highly elastic polyurethane-urea(PUU)with typical characteristics and 94% optical transmittance.Graphene platelets(GNPs)were prepared and modified via a scalable and eco-friendly mechanochemical approach.The produced GNPs is at 1.6-nm thickness with high electrical conductivity of~950 S/m.The structure-property relations of PUU/GNP nanocomposites were comprehensively investigated through morphology and mechanical properties measurements.The strong interface and high-density hydrogen bonds between modified GNPs(M-GNPs)and PUU significantly enhanced the mechanical properties of the PUU nanocomposite.The PUU composite showed 66.7%and 36.2%increments in tensile and impact strengths,respectively,at 0.2 wt% M-GNPs.The reversible hydrogen bond between M-GNPs and PUU endowed the nanocomposite with self-healing properties achieving 97.8% healing efficiency of the strength after 5 h at 120℃.This study demonstrates the importance of surface modification and provides a simple yet robust approach for preparing high-performance and functional PUU/graphene composites.
基金financially supported by the National Natural Science Foundation of China(No.52503154)Shandong Provincial Natural Science Foundation(Nos.ZR2022MB034 and ZR2025QC512)。
文摘Azobenzene-based polymer actuators show great promise for photoactuation owing to their unique photoisomerization behavior and tailorable molecular programmability.However,conventional systems are limited by inadequate mechanical robustness,self-healing,and recyclability,hindering their practical implementation.Herein,we present a high-performance azobenzene-functionalized polyurethane(AzoPU)elastomer actuator designed via molecular engineering of photoactive azobenzene moieties and dynamic disulfide bonds.AzoPU exhibits exceptional mechanical properties with retained performance after multiple reshaping cycles,enabled by well-engineered hard-soft segments and synergistic stress dissipation from weak covalent bonds/hierarchical hydrogen bonds.It achieves over 93%self-healing efficiency at room temperature owing to the synergistic interplay of disulfide bonds in the polymer backbone and intermolecular hydrogen bonds.Furthermore,it demonstrates remarkable light-triggered actuation behavior,achieving a phototropic bending angle exceeding 180°toward the light source within 45 s.To showcase its practical potential,proof-of-concept photoactuated devices with flower-,hook-,and gripper-like and local-orientation processed strip-shaped structures were fabricated,which exhibited rapid and reversible light-triggered deformation.This study proposes a novel strategy for the development of intelligent polymeric materials that integrate light responsiveness,self-healing,and recyclability,thus holding great promise for applications in flexible electronics,smart actuators,and sustainable functional materials.
基金funded by the LPDP-RIIM,Research Grant No.18/IV/KS/06/2022 and 4830/IT3.L1/PT.01.03/P/B/2022,titled Pengembangan Produk Oriented Strand Board Unggul dari Kayu Ringan dan Cepat Tumbuh dalam Rangka Pengembangan Produk Biokomposit Prospektif.
文摘Recent advancements in developing tannin-based non-isocyanate polyurethane(NIPU)resins have unlocked new possibilities for sustainable and eco-friendly wood adhesives.Unlike conventional polyurethane,NIPUs eliminate hazardous isocyanates,offering safer alternatives for industrial applications.Tannin,a naturally occurring polyphenolic compound,plays a pivotal role in enhancing these resins’fire-resistance and super-hydrophobic properties.This review highlights key developments in synthesizing tannin-based NIPU,focusing on various polymerization techniques such as polyaddition,polycondensation,ring-opening polymerization,and rearrangement.These strategies contribute to improved mechanical strength,thermal stability,and resistance to water absorption.Recent studies demonstrate that tannin-based NIPU adhesives meet or exceed international internal bonding strength,elasticity,and durability standards.Their application in wood-based composites like oriented strand boards(OSB)has shown promising results,offering improved resistance to moisture and superior dimensional stability.Furthermore,the cross-linked polymer network,supported by chemical modifications like the introduction of fluoroalkyl groups,significantly enhances hydrophobicity and fire retardancy.Despite these advancements,challenges remain in terms of scalability,cost,and integration with existing manufacturing processes.Future research should focus on optimizing reaction conditions,improving raw material availability,and developing industrial-scale production methods.This review underscores the potential of tannin-based NIPU resins as a viable and sustainable alternative for various wood composite applications.
基金support from the National Natural Science Foundation of China(Nos.22293011,T2341001)the Major Science and Technology Project of Anhui Province(202203a06020010).
文摘Epoxy resins are widely employed in wind turbine blades,drone rotors,and automotive interiors due to their excel-lent mechani-cal proper-ties and long service life.However,their insoluble and infusible cross-linked networks pose a significant re-cycling challenge,particularly with the impending retirement of the first generation of wind turbine blades.In this work,we reported a fully bio-based epoxy Vitrimer(FEP)incorporat-ing a dual-dynamic covalent network design and systematically investigated the influence of the 1,5,7-triazabicyclo[4.4.0]dec-5-ene(TBD)catalyst on its curing kinetics,thermal/mechan-ical properties,dynamic exchange behavior,and degradation performance in a mild alkaline solution.Compared to conventional epoxy resins,FEP exhibited superior tensile strength and elongation at break at an optimal TBD concentration(2 wt%),achieving an excellent strength-toughness balance.The presence of TBD accelerated the exchange rates of both disulfide and ester bonds,endowing FEP with notable stress relaxation at elevated tempera-tures.Moreover,FEP demonstrated complete dissolution in 1 mol/L NaOH within 6 h at 25℃.These results underscored the exceptional strength,toughness,and recyclability of FEP,positioning it as a promising,environmentally friendly matrix resin for next-generation appli-cations in the new energy sector.
基金supported by the National Natural Science Foundation of China(Nos.51603005,52403186 and 52573150)Fujian Provincial Natural Science Foundation of China(No.2024J011447)+1 种基金Natural Science Foundation of Xiamen,China(No.3502Z20227305)the Postdoctoral Fellowship Program of CPSF(No.GZC20240095)。
文摘Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,while lignin-based alternatives exhibit insufficient photothermal conversion efficiency.Herein,we developed a novel strategy to enhance photothermal performance of lignin through sequential demethylation modification and Fe^(3+)complexation for constructing NIR light responsive SMPs.Dealkaline lignin(DL)was first demethylated using iodocyclohexane to produce demethylated lignin(DDL)with increased catechol content,which was then incorporated into polycaprolactone-based polyurethane synthesis followed by Fe^(3+)complexation.Results showed that DDL-Fe^(3+)complexes have significantly enhanced photothermal conversion performance,and the resulting PU-DDL+Fe^(3+)polyurethane with 0.5 wt%DDL content demonstrated a temperature increases of 39.8℃under 0.33 W·cm-2808 nm NIR irradiation.This excellent photothermal performance enables the shape-fixed PU-DDL+Fe^(3+)polyurethane to rapidly recover to its initial shape under NIR light irradiation.Additionally,PU-DDL+Fe^(3+)polyurethane exhibits good mechanical properties and biocompatibility,demonstrating significant biomedical application potential.
基金financially supported by the Hubei Key Laboratory of Pollutant Analysis&Reuse Technology(No.PA230102)。
文摘Polyurethane elastomers exhibit high dielectric constants owing to their polar groups,and can be used as energy storage capacitors.Energy storage depends not only on the dielectric constant but also on the dielectric loss.However,the relationship between chain structure and dielectric properties is not yet clear.Ketal-containing crosslinked polyurethane elastomers were prepared using cyclic ketal diol as a chain extender.The effect of the soft segment length on the dielectric properties and energy storage was investigated.The cause of the change in the dipolar polarization with the soft segment length was analyzed.As the soft segment length increased,the hard-soft hydrogen bonding decreased,whereas the hard-hard hydrogen bonding increased.Under the action of an electric field,the polar bonds in the ketal-containing polyurethane elastomer overcome the hydrogen bonding between hard-soft segments to produce polarization;meanwhile,they also experience crankshaft motions to generate polarization.The former has a relatively high relaxation activation energy of approximately 10-20 k J·mol^(-1),resulting in a large dielectric loss.The latter has a relatively low relaxation activation energy,approximately 0.7-1.7 kJ·mol^(-1),leading to low dielectric loss.As a result,the dielectric constant showed a decreasing trend,and the dielectric loss gradually decreased.This study provides a theoretical foundation for improving the dielectric properties of polyurethane elastomers.
基金the financial support from the National Natural Science Foundation of China(22293011,T2341001)the Major Science and Technology Project of Anhui Province(202203a06020010)+1 种基金the Horizontal Project Provided by Jiangsu Zhuogao New Materials Technology Co.,Ltd.(Td00923003H)Joint Laboratory by China Power Investment Ronghe New Energy Technology Co.,Ltd.and the Central Government Guiding Special Fund Project for Local Science and Technology Development(202407a12020008)。
文摘The structural design and performance characteristics of the diaphragm have a decisive impact on the safety and electrochemical performance of lithium-ion batteries(LIBs).However,traditional polyolefin diaphragms still face challenges in simultaneously improving the ion transport efficiency and thermal stability.Here,we report an in situ dynamic lithium compensation strategy for manufacturing a biobased furan aramid/ceramic diaphragm(BAS)with higher thermal stability and ion transport efficiency.Specifically,exchangeable carboxyl groups(–COOH)are introduced into the bio-based furan aramid(BA)framework,which are in situ converted into–COOLi groups to form lithium ions(Li^(+))transport channels,achieving dynamic compensation of active Li^(+).The dual transmission system of ion exchange and physical pore channels synergistically enhances the ionic conductivity of BAS to 1.536 mS cm^(-1).The high polarity structure of the furan ring and the electrolyte have excellent compatibility,significantly reducing the solid–liquid interfacial energy,making BAS have extremely high electrolyte wettability(contact angle of 0°).The BA amide group forms a multi-scale bonding network with the nano-ceramics.The BAS prepared by the water-coating process exhibits excellent thermal stability(with a thermal shrinkage rate of less than 1%after 1 h at 150℃).The LiFePO_(4)|Li half-cell assembled with BAS shows a capacity retention rate of up to 91.7%after 280 cycles at 1C,with a Coulomb efficiency of 99%,demonstrating excellent cycling stability.This design and development based on bio-materials provides a new approach for high safety and high energy density battery systems.
文摘The development of intrinsically conductive piezoresistive sensors with high strain tolerance has garnered significant interest.While elastomeric polymers exhibit excellent strain capabilities,their utility in sensing applications has been limited by inherent challenges such as high electrical resistivity,poor aging resistance,and interfacial incompatibility.To address these limitations,hydroxyl-terminated polybutadiene(HTPB)-based polyurethane was chemically modified with acetylferrocene-polyaniline conductive moieties to enhance charge transport properties.Remarkably,this covalent functionalization endowed the resulting ferrocene-polyaniline hybrid polyurethane(FPHP)with a conductivity of2.33 n A at 1 V bias while preserving piezoresistive functionality.The FPHP demonstrated exceptional mechanical-electrical performance,achieving 254% elongation at break with strain-dependent gauge factors of 7.28(0%-12.5% strain,R^(2)=0.9504)and 19.66(12.5%-35.0% strain,R^(2)=0.9929).Further characterization revealed a rapid 0.60 s response time and stability over 3500 strain-release cycles at compression strain,underscoring its durability under repetitive loading.The FPHP sensor was capable of monitoring various human movements and recognizing writing signals.These advances establish a materials design paradigm for fabricating flexible sensors that synergistically integrate high deformability,tunable sensitivity,and robust operational stability,positioning FPHP as a promising candidate for next-generation wearable electronics and soft robotics.
基金supported by the Natural Science Foundation of Shandong Province(ZR2022QE042)China Postdoctoral Science Foundation(2023M741856)the National Natural Science Foundation of China(52172093).
文摘Pyrolysis technology has emerged as a promising method for converting waste polyurethane(WPU)from waste refrigerators into high-value chemicals.In this study,the copper(Cu)-assisted pyrolysis strategy was employed to enhance the thermal degradation efficiency and product quality of WPU.Kinetic analysis revealed that the activation energy(E_(a)) of the Cu-assisted pyrolysis was 136.64 kJ·mol^(−1) and Cu-assisted pyrolysis was controlled by the combined processes of diffusion,nucleation and phase boundary reactions.Comprehensive product analysis,including gas chromatography–mass spectrometry and thermogravimetric Fourier transform infrared spectroscopy–mass spectrometry suggested that Cu promoted the cleavage of urethane bonds and accelerated the decarboxylation of isocyanates,increasing the yields of aniline and ethanol at lower temperatures.Meanwhile,Cu effectively suppressed the formation of halogenated and heterocyclic compounds by promoting the cleavage of C–X(X=Cl,F)bonds through electron transfer interactions.Thus,the E_(a) is decreased and the halogenated compounds is reduced.This work provides the theoretical basis for converting waste to high-valued products through co-pyrolysis techniques.
基金financially supported by the National Natural Science Foundation of China(No.52303063)Hubei Provincial Department of Education Guided Scientific Research Project(No.B2024056)。
文摘Airless tires are essential for enhancing the safety,reliability,and convenience of maintenance of electric bicycles.Polyurethane(PU)is considered a promising candidate for such applications owing to its versatile properties.However,their use is limited by insufficient heat resistance and excessive dynamic heat generation under cyclic loading.In this study,star-shaped trifunctional polypropylene glycerol(PPG3)was incorporated into conventional poly(tetramethylene glycol)(PTMG)and 4,4'-methylenediphenyl diisocyanate(MDI)-based systems to construct microporous star-shaped casting polyurethanes(SCPU),with water serving as a green foaming agent.Unlike conventional small-molecule trifunctional crosslinkers that create junctions within hard segment domains,PPG3 introduces long flexible arms between the hard segments,anchoring the crosslinking points at its molecular core.The large steric hindrance of PPG3 effectively suppresses soft segment crystallization and lowers the degree of microphase separation,whereas the crosslinked network restricts chain mobility,thereby reducing dynamic heat generation.These structural features also enhance the heat resistance,yielding a softening temperature of 183℃,which is 30.9%higher than that of polyurethane without PPG3.When applied to airless tires by casting SCPU into rubber treads,the fabricated hybrid airless tires achieved a rolling distance of over 3000 km under a load of 65 kg at 25km/h without structural failure,satisfying practical performance requirements.This strategy offers a simple,solvent-free,and environmentally friendly process,underscoring the potential of SCPU for scalable production of high-performance airless tires.
基金supported by the Russian state-funded project for ICBFM SB RAS(grant number 125012300656-5)。
文摘Background:The development of materials for cardiovascular surgery that would improve the effectiveness of surgical interventions remains an important task.Surgical intervention during the implantation of vascular prostheses and stents,and the body’s reaction to artificial materials,could lead to chronic inflammation,a local increase in the concentration of proinflammatory factors,and stimulation of unwanted tissue growth.The introduction of nonsteroidal anti-inflammatory drugs into implantable devices could be used to obtain vascular implants that do not induce inflammation and do not induce neointimal tissue outgrowth.Methods:The scaffolds were made by electrospinning from mixtures of polyurethane(PU)with diclofenac(DF).The kinetics of DF release from the scaffolds composed of 3%PU/10%HSA/3%DMSO/DF and 3%PU/DF were studied.The biocompatibility and anti-inflammatory effects of the obtained scaffolds on human gingival fibroblasts and umbilical vein endothelial cells were studied.Results:Both types of scaffolds are characterized by fast DF release.The viability of cells cultured on scaffolds is 2 times worse than that of cells cultured on plastic.The level of the proinflammatory cytokine IL-6 in the culture medium of cells cultured on DF-containing scaffolds was lower than that of cells cultured on scaffolds without DF.Conclusion:The introduction of DF into scaffolds minimizes the inflammation caused by cell reactions to an artificial material.
基金supported by the National Natural Science Foundation of China(No.51905543)。
文摘This study aimed to systematically regulate the performance of 4D printing composites by investigating the synergistic effects of dicumyl peroxide(DCP)and maleic anhydride-grafted polyethylene(MAH-g-PE)on a poly(lactic acid)/thermoplastic polyurethane(PLA/TPU)matrix.Specifically,using a 70 wt%/30 wt%PLA/TPU matrix and an L_(9)(3^(2))orthogonal design,composites were evaluated via morphology,shape memory,mechanical tests,and multi-criteria analysis.Moderate DCP enhanced crosslinking,improving storage modulus and thermal stability,while excessive DCP caused brittleness.Furthermore,MAH-g-PE effectively improved interfacial compatibility,and its synergy with DCP was dosage-dependent.Consequently,Sample 5 achieved optimal performance,exhibiting uniform fracture morphology,a shape fixation rate of98.8%with the fastest recovery,and balanced strength-ductility.Multi-criteria analysis identified elongation at break and recovery time as the top contributing factors,with consistent rankings validated by Spearman analysis(ρ=0.833,p<0.01).In summary,adjusting DCP and MAH-g-PE contents effectively modulates the crosslinking structure and interfacial properties of PLA/TPU composites,providing a viable strategy for developing high-performance,tunable 4D printing materials.
基金supported by the National Natural Sci-ence Foundation of China(Nos.U21A20288 and 21978280).
文摘Developing green and efficient methods to acquire lignocellulose-based chemicals with high added value is beneficial for facilitating green chemistry and sustainable development.The goal of this study is to demonstrate that bio-based benzaldehyde,a noteworthy high-value chemical,is able to be directionally prepared from lignocellulosic biomass.This new control-lable transformation was materialized by uniting catalytic-pyrolysis of lignocellulose to toluene intermediate and catalytic oxidation of toluene intermediate to bio-based benzalde-hyde.This work also developed a highly active magnetic catalyst(CoFe_(2)O_(4)@Biochar(HTR)),achieving 77.1%benzaldehyde selectivity and 46.7%benzaldehyde yield using this catalyst.It was found that introducing the biochar carrier into the cobalt iron composite metal oxide cat-alyst enhanced hydroxyl radical formation and bio-based benzaldehyde synthesis.Based on catalyst characterizations and hydroxyl radical analysis,potential reaction mechanism for bio-based benzaldehyde synthesis was proposed.This strategy may provide a beneficial pathway for developing high-value bio-based chemical(benzaldehyde)using renewable lignocellulosic biomass.
基金supported by the National Natural Science Foundation of China(Nos.22175123,52122302,and 51991351)the 111 Project(No.B20001)Fundamental Research Funds for the Central Universities,and Open and Innovative Fund of Hubei Three Gorges Laboratory(Nos.2022LF2021 and SC213011).
文摘Bio-based polyurethane foam has attracted increasing attentions due to eco-friendliness and fossil feedstock issues.However,the inherent flammability limits its application in different fields.Herein,we demonstrate a green bio-based flame-retardant system to fabricate polyurethane foam composite with durable flame retardancy,smoke suppression,and thermal insulation property.In this system,the green bio-based polyol(VED)with good reactivity and compatibility plays a role of flame retardant and EG acts as a synergistic filler.As a result,the LOI value of foam composite increased to 30.5 vol.%and it achieved a V-0 rating in the UL-94 vertical burning test.Additionally,the peak heat release rate(pHRR)and the total smoke production(TSP)decreased by 66.1%and 63.4%,respectively.Furthermore,the foam composite maintained durable flame retardancy after accelerated thermal aging test,whose thermal-insulating property was maintained even after being treated in high-humidity environment with 85%R.H.for a week.This work provides a facile strategy for durable flame retardancy and long-term thermal insulation performance,and creates opportunities for the practical applications of bio-based foam composites.
基金by the Research and Development Program in Key Areas of Guangdong Province(Grant No.2020B0202010008)Guangdong Province Science&Technology Program(2018B030306016)+1 种基金Guangdong Provincial Innovation Team for General Key Technologies in Modern Agricultural Industry(2019KJ133)Key Projects of Basic Research and Applied Basic Research of the Higher Education Institutions of Guangdong Province(2018KZDXM014).
文摘In this study,acrylic acid was used as a neutralizer to prepare bio-based WPU with an interpenetrating polymer network structure by thermally induced free radical emulsion polymerization.The effects of the content of acrylic acid on the properties of the resulting waterborne polyurethane-poly(acrylic acid)(WPU-PAA)dispersion and the films were systematically investigated.The results showed that the cross-linking density of the interpenetrating network polymers was increased and the interlocking structure of the soft and hard phase dislocations in the molecular segments of the double networks was tailored with increasing the content of acrylic acid,leading to enhancement of the mechanical properties and water resistance of WPU-PAA films.Notably,with the increase in content of acrylic acid,the tensile strength,Young’s modulus,and toughness of the WPU-PAA-110 film increased by 3 times,and 8 times,and 2.4 times compared with WPU-PAA-80,respectively.The WPU-PAA-100 film showed the best water resistance,and the water absorption rate at 96 h was only 3.27%.This work provided a new design scheme for constructing bio-based WPU materials with excellent properties.
