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Bio-based polyurethane for road engineering applications:A comprehensive review
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作者 Qingxu Li Zengping Zhang +3 位作者 Zhongbao Shi Yekun Zhang Xiaoyi Ban Hao Liu 《Journal of Road Engineering》 2025年第4期513-530,共18页
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
关键词 bio-based materials polyurethane Life cycle assessment Environmentally friendly
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High Performance Bio-based Polyurethane Elastomers: Effect of Different Soft and Hard Segments 被引量:7
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作者 Bin Cui Qing-Yun Wu +2 位作者 顾林 Liang Shen 余海斌 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2016年第7期901-909,共9页
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
关键词 Polylactide diols bio-based polyurethane Shape memory BIOCOMPATIBILITY
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Elastic Bio-based Polyurethane Nanofibrous Membrane with Robust Waterproof and Breathable Properties 被引量:5
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作者 刘浩克 王婷 +3 位作者 闫子硕 斯阳 俞建勇 丁彬 《Journal of Donghua University(English Edition)》 CAS 2023年第3期237-246,共10页
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
关键词 bio-based polyurethane(PU) ELECTROSPINNING WATERPROOF breathable membrane
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Eco-friendly physical blowing agent mass loss of bio-based polyurethane rigid foam materials
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作者 Haozhen Wang Lin Lin Yingshu Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第4期782-789,共8页
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
关键词 polyurethane bio-based polyol eco-friendly physical blowing agent mass loss
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Diclofenac-enriched polyurethane-based scaffolds produced by electrospinning: drug release, cytotoxicity, and anti-inflammatory effect
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作者 Zhanna Konstantinovna Nazarkina Boris Pavlovich Chelobanov +1 位作者 Ren Il Kvon Pavel Petrovich Laktionov 《Biomedical Engineering Communications》 2026年第1期26-34,共9页
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
关键词 DICLOFENAC ELECTROSPINNING drug-enriched scaffolds polyurethane cardiovascular tissue engineering vascular grafts and stents drug delivery
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Durable flame-retardant,smoke-suppressant,and thermal-insulating biomass polyurethane foam enabled by a green bio-based system 被引量:5
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作者 Xue-Lian Chen Fu-Rong Zeng +8 位作者 Wen-Xiong Li Lin Zhang Cong Deng Yi Tan Ming-Jun Chen Sheng-Chao Huang Bo-Wen Liu Yu-Zhong Wang Hai-Bo Zhao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第31期179-188,共10页
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
关键词 Biomass polyurethane foam composite Green bio-based system Durable flame retardancy Smoke suppression Long-term thermal insulation
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High Water Resistance and Enhanced Mechanical Properties of Bio-Based Waterborne Polyurethane Enabled by in-situ Construction of Interpenetrating Polymer Network 被引量:1
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作者 Henghui Deng Jingyi Lu +5 位作者 Dunsheng Liang Xiaomin Wang Tongyao Wang Weihao Zhang Jing Wang Chaoqun Zhang 《Journal of Renewable Materials》 SCIE EI 2023年第3期1209-1222,共14页
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
关键词 bio-based waterborne polyurethane interpenetrating polymer network highly water resistance superior mechanical performance
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Bio-Based Trivalent Phytate:A Novel Strategy for Enhancing Fire Performance of Rigid Polyurethane Foam Composites 被引量:2
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作者 Bing Zhang Sujie Yang +4 位作者 Mengru Liu Panyue Wen Xiuyu Liu Gang Tang Xiangrong Xu 《Journal of Renewable Materials》 SCIE EI 2022年第5期1201-1220,共20页
Biomass phytic acid has potential flame retardant value as the main form of phosphorus in plant seeds.In this study,phytate-based flame retardants aluminum phytate(PA-Al)and iron phytate(PA-Fe)were synthesized and cha... Biomass phytic acid has potential flame retardant value as the main form of phosphorus in plant seeds.In this study,phytate-based flame retardants aluminum phytate(PA-Al)and iron phytate(PA-Fe)were synthesized and characterized.Subsequently,they were introduced into rigid polyurethane foam(RPUF)as flame retardants by one-step water-blown method.The results indicated that RPUF/PA-Fe30 exhibited the highest char residue of 22.1 wt%,significantly higher than 12.4 wt%of RPUF.Cone calorimetry analysis showed that the total heat release(THR)of RPUF/PA-Al30 decreased by 17.0%and total smoke release(TSR)decreased by 22.0%compared with pure RPUF,which were the lowest,demonstrating a low fire risk and good smoke suppression.Thermogravimetric analysis-Fourier transform infrared spectrometer(TG-FTIR)implied the release intensity of flammable gases(hydrocarbons,esters)and toxic gases(isocyanate,CO,aromatic compounds,HCN)of composites was significantly reduced after the addition of PA-Fe.The analysis of char residue indicated that the RPUF composites formed a dense char layer with a high degree of graphitization after the addition of PA-Al/PA-Fe,endowing RPUF composites with excellent mass&heat transmission inhibition effect and fire resistance in the combustion process. 展开更多
关键词 bio-based flame retardant phytic acid salt rigid polyurethane foam COMPOSITES smoke&toxicity suppression
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Injectable and in situ foaming shape-adaptive porous Bio-based polyurethane scaffold used for cartilage regeneration 被引量:2
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作者 Abudureheman Bahatibieke Shuai Wei +9 位作者 Han Feng Jianming Zhao Mengjiao Ma Junfei Li Yajie Xie Kun Qiao Yanseng Wang Jiang Peng Haoye Meng Yudong Zheng 《Bioactive Materials》 SCIE CSCD 2024年第9期1-13,共13页
Irregular articular cartilage injury is a common type of joint trauma,often resulting from intense impacts and other factors that lead to irregularly shaped wounds,the limited regenerative capacity of cartilage and th... Irregular articular cartilage injury is a common type of joint trauma,often resulting from intense impacts and other factors that lead to irregularly shaped wounds,the limited regenerative capacity of cartilage and the mismatched shape of the scaffods have contributed to unsatisfactory therapeutic outcomes.While injectable materials are a traditional solution to adapt to irregular cartilage defects,they have limitations,and injectable materials often lack the porous microstructures favorable for the rapid proliferation of cartilage cells.In this study,an injectable porous polyurethane scaffold named PU-BDO-Gelatin-Foam(PUBGF)was prepared.After injection into cartilage defects,PUBGF forms in situ at the site of the defect and exhibits a dynamic microstructure during the initial two weeks.This dynamic microstructure endows the scaffold with the ability to retain substances within its interior,thereby enhancing its capacity to promote chondrogenesis.Furthermore,the chondral repair efficacy of PUBGF was validated by directly injecting it into rat articular cartilage injury sites.The injectable PUBGF scaffold demonstrates a superior potential for promoting the repair of cartilage defects when compared to traditional porous polyurethane scaffolds.The substance retention ability of this injectable porous scaffold makes it a promising option for clinical applications. 展开更多
关键词 INJECTABLE In situ forming polyurethane Cartilage repair Tissue engineering
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Bio-based conductive polyurethane composites derived from renewable castor oil with enhanced self-healing ability for flexible supercapacitors 被引量:1
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作者 Van-Phu Vu Seung-Hyun Kim +3 位作者 Van-Dung Mai Sooyeon Ra Sangmin An Soo-Hyoung Lee 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第21期44-61,共18页
To alleviate the pressure on the petrochemical industry and address environmental concerns,the utilization of polyurethane(PU)derived from castor oil(CO)(as an ester polyol replacement of petrochemicalbased materials)... To alleviate the pressure on the petrochemical industry and address environmental concerns,the utilization of polyurethane(PU)derived from castor oil(CO)(as an ester polyol replacement of petrochemicalbased materials)has garnered significant attention in recent decades.Extending the service life of materials requires imparting self-healing properties to vegetable oil-based polymers,an aspect that has received limited attention in current studies.However,low self-healing efficiency still poses a significant challenge,and non-conductivity also remains an obstacle in current research,crucial for their application in electronic devices.In this work,we present the first series of electrically self-healing biopolymer composites constructed by incorporating carbon nanotube(CNT)networks into crosslinked castor oil-based polyurethane(BPU)through a simple curing process.These materials address the challenges mentioned above and exhibit improved mechanical,electrical,and self-healing capabilities compared to other biobased self-healing materials.The resulting BPU/CNT composite demonstrated exceptional repeated selfhealing capacity,restoring both mechanical properties and electrical performance even after experiencing severe mechanical damage.Notably,this composite served as a conductive substrate in flexible solid-state supercapacitor(FSSC)devices.Consequently,the FSSC derived from the composite conductive substrate achieved an impressive 92.4%self-healing efficiency even after undergoing 7 cutting/healing cycles.The device remained virtually unchanged even after being bent at a 180°angle with a bending radius of 1.6 mm,indicating excellent repeatability and durability.The exceptional self-healing ability,with∼98%electrical recovery at 100℃for 70 s and 93%at 80℃after 6 min,of these composites was attributed to the synergistic interactions of the dynamic exchange reactions of disulfide bonds and dense hydrogen bonds within the BPU matrix,which provide a reversible dynamic polymer network.The healing efficiency of these dynamic bonds was evaluated by adjusting the composition ratio of the long linear chain of pTHF in hybrid polyols of the crosslinked polymer network.Overall,this work highlights a series of green,simple,and highly efficient self-healing polymer composites derived from renewable castor oil,and it establishes an essential framework for future sustainable polymer composite design. 展开更多
关键词 Natural oils Castor oil-based polyurethane SELF-HEALING Conductivity Flexible supercapacitor
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Erratum to“Bio-based conductive polyurethane composites derived from renewable castor oil with enhanced self-healing ability for flexible supercapacitors”[Journal of Materials Science&Technology,Volume 188,20 July 2024,Pages 44-61]
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作者 Van-Phu Vu Seung-Hyun Kim +3 位作者 Van-Dung Mai Sooyeon Ra Sangmin An Soo-Hyoung Lee 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第21期270-270,共1页
The Publisher regrets that the Graphical Abstract(see below)was missed due to a transmittal problem,and it was not published with the original article.
关键词 composites SUPERCAPACITOR polyurethane
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Bio-Based Rigid Polyurethane Foams for Cryogenic Insulation
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作者 Laima Vevere Beatrise Sture +2 位作者 Vladimir Yakushin Mikelis Kirpluks Ugis Cabulis 《Journal of Renewable Materials》 EI CAS 2024年第3期585-602,共18页
Cryogenic insulation material rigid polyurethane(PU)foams were developed using bio-based and recycled feedstock.Polyols obtained from tall oil fatty acids produced as a side stream of wood biomass pulping and recycled... Cryogenic insulation material rigid polyurethane(PU)foams were developed using bio-based and recycled feedstock.Polyols obtained from tall oil fatty acids produced as a side stream of wood biomass pulping and recycled polyethylene terephthalate were used to develop rigid PU foam formulations.The 4th generation physical blowing agents with low global warming potential and low ozone depletion potential were used to develop rigid PU foam cryogenic insulation with excellent mechanical and thermal properties.Obtained rigid PU foams had a thermal conductivity coefficient as low as 0.0171 W/m·K and an apparent density of 37-40 kg/m^(3).The developed rigid PU foams had anisotropic compression strength properties,which were higher parallel to the foaming direction.Moreover,the compression strength was also influenced by the type of applied bio-based polyol.The bio-based polyols with higher OH group functionality delivered higher crosslinking density of polymer matrix;thus,the mechanical properties were also higher.The mechanical strength of the foams increased when materials were tested at liquid nitrogen temperature due to the stiffening of the polymer matrix.The thermal properties of the developed materials were determined using differential scanning calorimetry,dynamic mechanical analysis,and thermogravimetric analysis methods.Lastly,the developed rigid PU foams had good adhesion to the aluminium substrate before and after applying cyroshock and an excellent safety coefficient of 4-5.Rigid PU foams developed using Solstice LBA delivered adhesion strength of~0.5 MPa and may be considered for application as cryogenic insulation in the aerospace industry. 展开更多
关键词 Cryogenic insulation polyurethanes tall oil 4th generation physical blowing agents
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Synthesis of Biomass Polyurethane and Its Properties
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作者 Zhen-Yu Chen Yue-RU Wang +2 位作者 De-Yi Teng Yan-Fang Xue Gui-Chang Jiang 《Journal of Polymer Materials》 2025年第2期359-377,共19页
PU,or polyurethane,features a repeating urethane group(-NH-COO-)in its molecular structure.Traditionally,PUs are synthesized from isocyanate and polyol compounds derived from fossil resources through polymerization re... PU,or polyurethane,features a repeating urethane group(-NH-COO-)in its molecular structure.Traditionally,PUs are synthesized from isocyanate and polyol compounds derived from fossil resources through polymerization reactions.The depletion of fossil fuels and the increasing climate problems call for the expansion of more renewable sources of chemicals,such as modern biomass.However,the conversion of biomass into chemicals is challenging due to the inherent molecular complexity of its composition.In recent years,advances in green chemistry have led researchers to focus on developing bio-based polyurethanes by sourcing polyols,isocyanates,and chain extender precursors from biological materials.This paper focuses on the preparation of polyols,non-isocyanates and bio-based chain extenders from bio-based materials such as vegetable oils,lignin,sugars,and rosin.The synthetic routes and properties of several bio-based polyurethane materials are analyzed.Additionally,it discusses the current status,future challenges,and potential applications of bio-based polyurethane materials across various fields. 展开更多
关键词 bio-based polyurethane bio-based polyols bio-based non-isocyanates bio-based chain extender
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Mechanism Study on the Effect of Retarder on Polyurethane Setting Time Based on Molecular Simulation
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作者 WU Yuxuan XU Wenyuan +1 位作者 YU Tianlai JI Yongcheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期224-231,共8页
This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal dosages.The mechanism by which phosphate ester affects the setti... This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal dosages.The mechanism by which phosphate ester affects the setting time of polyurethane was further investigated using molecular dynamics simulations.Fourier transform infrared spectroscopy was also employed to systematically study the physical and chemical interactions between phosphate esters and polyurethane materials.The results demonstrate that a 1%concentration of phosphate ester provides the most effective retarding effect with minimal impact on the strength of polyurethane.When phosphate ester is added to the B component of the two-component polyurethane system,its interaction energy with component A decreases,as do the diffusion coefficient and aggregation degree of component B on the surface of component A.This reduction in interaction slows the setting time.Additionally,the addition of phosphate ester to polyurethane leads to the disappearance or weakening of functional groups,indicating competitive interactions within the phosphate ester components that inhibit the reaction rate. 展开更多
关键词 polyurethane RETARDER setting time molecular dynamics diffusion coefficient
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Experimental and numerical analysis of polyurethane spraying materials as a compressible layer in deep soft rock tunnels 被引量:1
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作者 Haibo Wang Fuming Wang +3 位作者 Tongming Qu Jun Liu Lei Qin Chengchao Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期3018-3034,共17页
Polyurethane foam,when used as a compressible layer in deep soft rock tunnels,offers a feasible solution to reduce the support pressure on the secondary lining.The foam spraying method using sprayed polyurethane mater... Polyurethane foam,when used as a compressible layer in deep soft rock tunnels,offers a feasible solution to reduce the support pressure on the secondary lining.The foam spraying method using sprayed polyurethane material is convenient for engineering applications;however,the compressive behaviour and feasibility of sprayed polyurethane material as a compressible layer remain unclear.To address this gap,this study conducts uniaxial compression tests and scanning electron microscope(SEM)tests to investigate the compressive behaviour of the rigid foams fabricated from a self-developed polyurethane spray material.A peridynamics model for the composite lining with a polyurethane compressible layer is then established.After validating the proposed method by comparison with two tests,a parametric study is carried out to investigate the damage evolution of the composite lining with a polyurethane compressible layer under various combinations of large deformations and compressible layer parameters.The results indicate that the polyurethane compressible layer effectively reduces the radial deformation and damage index of the secondary lining while increasing the damage susceptibility of the primary lining.The thickness of the polyurethane compressible layer significantly influences the prevention effect of large deformation-induced damage to the secondary lining within the density range of 50e100 kg/m^(3).In accordance with the experimental and simulation results,a simple,yet reasonable and convenient approach for determining the key parameters of the polyurethane compressible layer is proposed,along with a classification scheme for the parameters of the polyurethane compressible layer. 展开更多
关键词 polyurethane compressible layer Deep soft rock tunnel Compressive behaviour PERIDYNAMICS Damage evolution
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Model tests and numerical analysis of emergency treatment of cohesionless soil landslide with quick-setting polyurethane 被引量:1
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作者 ZHANG Zhichao TANG Xuefeng +2 位作者 HUANG Rufa CAI Zhenjie GAO Anhua 《Journal of Mountain Science》 2025年第1期110-121,共12页
Shotcrete is one of the common solutions for shallow sliding.It works by forming a protective layer with high strength and cementing the loose soil particles on the slope surface to prevent shallow sliding.However,the... Shotcrete is one of the common solutions for shallow sliding.It works by forming a protective layer with high strength and cementing the loose soil particles on the slope surface to prevent shallow sliding.However,the solidification time of conventional cement paste is long when shotcrete is used to treat cohesionless soil landslide.The idea of reinforcing slope with polyurethane solidified soil(i.e.,mixture of polyurethane and sand)was proposed.Model tests and finite element analysis were carried out to study the effectiveness of the proposed new method on the emergency treatment of cohesionless soil landslide.Surcharge loading on the crest of the slope was applied step by step until landslide was triggered so as to test and compare the stability and bearing capacity of slope models with different conditions.The simulated slope displacements were relatively close to the measured results,and the simulated slope deformation characteristics were in good agreement with the observed phenomena,which verifies the accuracy of the numerical method.Under the condition of surcharge loading on the crest of the slope,the unreinforced slope slid when the surcharge loading exceeded 30 k Pa,which presented a failure mode of local instability and collapse at the shallow layer of slope top.The reinforced slope remained stable even when the surcharge loading reached 48 k Pa.The displacement of the reinforced slope was reduced by more than 95%.Overall,this study verifies the effectiveness of polyurethane in the emergency treatment of cohesionless soil landslide and should have broad application prospects in the field of geological disasters concerning the safety of people's live. 展开更多
关键词 Cohesionless soil landslide polyurethane Emergency treatment Reinforcement effect Model test Finite element analysis
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Synthesis,Mechanical Characteristic and Near-infrared Reflective Property of Perylene Diimide-containing Polyurethane
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作者 SONG Yifan LI Zixin +7 位作者 TIAN Kaili BERMESHEV Maxim V HU Yanghao SU Yupeng WANG Jie PAN Hongfei LI He REN Xiangkui 《发光学报》 北大核心 2025年第7期1326-1332,共7页
Doping perylene diimide(PDI)into a polymer matrix is a simple strategy to prepare near-infrared(NIR)reflective materials,but the mechanical properties and NIR reflectance properties are significantly compromised due t... Doping perylene diimide(PDI)into a polymer matrix is a simple strategy to prepare near-infrared(NIR)reflective materials,but the mechanical properties and NIR reflectance properties are significantly compromised due to macro-phase separation.In this study,a novel polymer(denoted as PU-PDI)with intrinsic NIR reflective proper⁃ties was synthesized by covalent incorporation of PDI units into polyurethane chains.Its photophysical characteris⁃tics,mechanical property and NIR reflectance property are investigated in detail.The results show that covalent in⁃corporation reduces the severe aggregation of PDI units,thereby endows PU-PDI with excellent mechanical property.The elongation at break of PU-PDI can reach more than 700%,and the breaking strength is 34.11 MPa.Moreover,compared to the blending system,PU-PDI possesses enhanced NIR reflection ability due to the better dispersion of PDI units. 展开更多
关键词 perylene diimide polyurethane near-infrared(NIR)reflectance
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Coapplication of polyurethane microplastics and fertilizer accelerates CO_(2) emission in an infertile soil
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作者 Dong LIANG Qiaolin ZHOU +3 位作者 Haiying LU Jianwei ZHANG Cheng JI Jidong WANG 《Pedosphere》 2025年第1期289-294,共6页
Dear Editor,Environmental pollution from microplastics(MPs)has recently gained attention as a potential environmental hazard(Chia et al.,2021).Agricultural soils could contain more MPs than the ocean by 2050 because m... Dear Editor,Environmental pollution from microplastics(MPs)has recently gained attention as a potential environmental hazard(Chia et al.,2021).Agricultural soils could contain more MPs than the ocean by 2050 because more MPs enter the soil than the ocean(Nizzetto et al.,2016).The carbon(C)-C backbone of degradation-resistant MPs provides considerable stability in the soil,where they can remain for several decades(Iqbal et al.,2023). 展开更多
关键词 SOIL polyurethane BACKBONE
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Preparation and application of nano dendritic polyurethane for high-efficiency boron adsorption
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作者 Pengyu Sun Feiyu Gao +4 位作者 Wei Shi Hengyuan Zhang Shiao Du Wei Chen Meng Li 《Chinese Journal of Chemical Engineering》 2025年第6期209-221,共13页
Boron adsorbents with high adsorption capacities have long been a focus of research for a long time.This study used small molecular polyols with different hydroxyl groups as functional monomers and as end-capping agen... Boron adsorbents with high adsorption capacities have long been a focus of research for a long time.This study used small molecular polyols with different hydroxyl groups as functional monomers and as end-capping agents,functional dendritic polyurethanes with nano structure were successfully prepared by one-pot method.The single molecule size and surface morphology were characterized by dynamic light scattering,transmission electron microscopy and scanning electron microscopy,and the molecular size in the dry state was 11 to 18 nm.The prepared materials were used as the boron adsorbents,and the effects of pH,time,boron solution concentration and temperature on the adsorption were studied.The results showed that the capacity of adsorbed boron could reach 110-130 mg·g^(-1).Adsorption was a homogeneous monolayer adsorption controlled by chemisorption,and adsorption thermodynamics showed that was a spontaneous endothermic process.Adsorption behavior was best described by the pseudo-second-order kinetic model and the Langmuir isotherm.This study also showed that it was difficult for ortho/meta-hydroxyl groups to chelate with H_(3)BO_(3) and other polyborates,and the chelates mainly had good chelating properties with B(OH)_(4)^(-),and the chelates formed had large steric hindrance.At the same time,increasing the number of hydroxyl groups of functional monomers was beneficial to increase the adsorption capacity of materials.In addition,the cyclic adsorption/desorption experiments showed that DPUs have good cyclic stability.At the same time,the adsorption results of the original salt lake brine showed that other metal ions in the brine had little effect on the adsorption of boron,and the adsorption capacity was as high as52.93 mg·g^(-1),and the maximum adsorption capacity was obtained by Adams-Bohart model to58.80 mg·g^(-1).The outstanding selectivity and adsorption capacity of these materials have broad potential application,and are expected to be used for the efficient adsorption and removal in boroncontaining water bodies. 展开更多
关键词 BORON ADSORBENT Dendritic polyurethane CHELATION
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Bio-based Epoxy Composites Demonstrating High Temperature Breakdown Strength and Thermal Conductivity for High Voltage Insulation
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作者 Ke-Rong Yang Jin-Yue Dai +2 位作者 Shuai-Peng Wang Wei-Wei Zhao Xiao-Qing Liu 《Chinese Journal of Polymer Science》 2025年第1期40-52,I0006,共14页
The demand for energy-efficient and environmental-friendly power grid construction has made the exploitation of bio-based electrical epoxy resins with excellent properties increasingly important.This work developed th... The demand for energy-efficient and environmental-friendly power grid construction has made the exploitation of bio-based electrical epoxy resins with excellent properties increasingly important.This work developed the bio-based electrotechnical epoxy resins based on magnolol.High-performance epoxy resin(DGEMT)with a double crosslinked points and its composites(Al_(2)O_(3)/DGEMT)were obtained taking advantages of the two bifunctional groups(allyl and phenolic hydroxyl groups)of magnolol.Benefitting from the distinctive structure of DGEMT,the Al_(2)O_(3)/DGEMT composites exhibited the advantages of intrinsically high thermal conductivity,high insulation,and low dielectric loss.The AC breakdown strength and thermal conductivity of Al_(2)O_(3)/DGEMT composites were 35.5 kV/mm and 1.19 W·m-1·K-1,respectively,which were 15.6%and 52.6%higher than those of petroleum-based composites(Al_(2)O_(3)/DGEBA).And its dielectric loss tanδ=0.0046 was 20.7%lower than that of Al_(2)O_(3)/DGEBA.Furthermore,the mechanical,thermal and processing properties of Al_(2)O_(3)/DGEMT are fully comparable to those of Al_(2)O_(3)/DGEBA.This work confirms the feasibility of manufacturing environmentally friendly power equipment using bio-based epoxy resins,which has excellent engineering applications. 展开更多
关键词 bio-based epoxy composites MAGNOLOL Breakdown strength Thermal conductivity Dielectric loss
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