Smart pesticide delivery systems based on stimuli-responsive nanocarriers have attracted considerable attention because of their potential to enhance pesticide efficiency while reducing environmental risks.In this stu...Smart pesticide delivery systems based on stimuli-responsive nanocarriers have attracted considerable attention because of their potential to enhance pesticide efficiency while reducing environmental risks.In this study,a novel p H/glutathione dual-responsive pesticide delivery system was constructed through the synthesis of disulfide-bridged hollow mesoporous organosilica nanospheres(HMONs)via the St??ber method,followed by poly(acrylic acid)(PAA)coating through distillation-precipitation polymerization to form HMONs@PAA nanocomposites.The resulting abamectin-loaded system(Abamectin-HMONs@PAA)demonstrated a 12.73% pesticide loading capacity and significantly improved photostability,retaining twice as much active ingredient as free abamectin after 250 h of UV irradiation(36 W).Release studies revealed p H-and glutathione-dependent characteristics,with cumulative releases in acidic conditions exceeding those in neutral and alkaline environments by 18.66% and 40.98%,respectively,and a 14.2% increase in glutathione-containing solution(0.2 mmol·L^(-1) in 70% ethanol)after 97 h.Bioassays showed superior performance against Plutella xylostella,with a 13.33% reduction in survival rate compared to conventional suspension at equivalent dosage(40 mg·L^(-1)),while maintaining efficacy after extensive rainfall simulation(20 events over 10 days).This study provides a promising approach for developing environmentally responsive nanopesticides with enhanced durability and controlled-release properties,offering significant potential for sustainable crop protection.展开更多
Herein,manganese(Mn)‑doped poly(1,5‑diaminonaphthalene)(PN)electrode material(Mn@PN)was synthesized via chemical oxidative polymerization.The material′s distinctive vesicular architecture enables rapid ion transport ...Herein,manganese(Mn)‑doped poly(1,5‑diaminonaphthalene)(PN)electrode material(Mn@PN)was synthesized via chemical oxidative polymerization.The material′s distinctive vesicular architecture enables rapid ion transport while maintaining the structural stability of the electrode under continuous charge‑discharge cycles.Electrochemical characterization under a three‑electrode system revealed exceptional rate capability:Mn@PN delivered an ultrahigh specific capacitance of 10318 F·g^(-1) at a low current density of 3 A·g^(-1) and retained 9415 F·g^(-1)(91.2%retention compared to the value at 3 A·g^(-1))even at an ultrahigh current density of 50 A·g^(-1).Moreover,the material exhibited 97.4%capacitance retention after 9000 cycles at 30 A·g^(-1),corresponding with a low capacitance decay rate of 0.003‰per cycle,significantly outperforming conventional conductive polymers like polyaniline(PANI).An asymmetric supercapacitor assembled with Mn@PN as the positive electrode(Mn@PN||AC)achieved an energy density of 328 Wh·kg^(-1) at 15 A·g^(-1) and retained 80.7%of its initial specific capacitance after 4000 cycles at 20 A·g^(-1).展开更多
Consisting of natural histidine residues,polyhistidine(PHis)simulates functional proteins.Traditional approaches towards PHis require the protection of imidazole groups before monomer synthesis and polymerization to p...Consisting of natural histidine residues,polyhistidine(PHis)simulates functional proteins.Traditional approaches towards PHis require the protection of imidazole groups before monomer synthesis and polymerization to prevent degradation and side reactions.In the contribution,histidine N-thiocarboxyanhydride(His-NTA)is directly synthesized in aqueous solution without protection.With the self-catalysis of the imidazole side group,the ring-closing reaction to form His-NTA does not require any activating reagent(e.g.,phosphorus tribromide),which is elucidated by density functional theory(DFT)calculations.His-NTA directly polymerizes into PHis bearing unprotected imidazole groups with designable molecular weights(4.2-7.7 kg/mol)and low dispersities(1.10-1.19).Kinetic experiments and Monte Carlo simulations reveal the elementary reactions and the relationship between the conversion of His-NTA and time during polymerization.Block copolymerization of His-NTA with sarcosine N-thiocarboxyanhydride(Sar-NTA)demonstrate versatile construction of functional polypept(o)ides.The triblock copoly(amino acid)PHis-b-PSar-b-PHis is capable to reversibly coordinate with transition metal ions(Fe^(2+),Co^(2+),Ni^(2+),Cu^(2+)and Zn^(2+))to form pH-sensitive hydrogels.展开更多
In-situ poly(1,3-dioxolane)(PDOL)-based electrolyte has received extensive attention in the research of lithium metal batteries due to its high stability to lithium anode and simple processing.However,it is still face...In-situ poly(1,3-dioxolane)(PDOL)-based electrolyte has received extensive attention in the research of lithium metal batteries due to its high stability to lithium anode and simple processing.However,it is still faced with defects such as low intrinsic ionic conductivity,a narrow electrochemical window,and poor thermal stability.A crosslinking and fluorination molecular design strategy toward PDOL is proposed to tackle the issues above.The amorphous crosslinked structure effectively improves ionic conductivity by inhibiting long-chain crystallization.Especially,the antioxidant–CF_(3)groups,stable crosslinked structure,and reduced terminal hydroxyl groups significantly enhance the electrochemical oxidation stability with a superb high-voltage window of 4.7 V.In addition,the designed electrolyte also exhibits obviously improved thermal stability with no deformation at 120°C for 5 min.Furthermore,the semi-solid NCM811||Li batteries exhibit a favourable capacity retention of 88.8%after 150 cycles at 0.5 C.Even assembled with NCM622 cathode working at 4.5 V,the semi-solid batteries can still show a satisfactory capacity retention of 85.3%after 100 cycles at 0.5 C.Also,a 0.1 Ah NCM811||Li pouch cell with active materials loading of 9 mg/cm2 demonstrates satisfactory cycling stability and working ability,which shows promising practical application prospects.展开更多
Bio-based 2,5-furandicarboxylic acid polyesters offer significant promise for reducing energy and environmental crises.However,their intrinsic flammability remains a critical limitation,and conventional flame-retardan...Bio-based 2,5-furandicarboxylic acid polyesters offer significant promise for reducing energy and environmental crises.However,their intrinsic flammability remains a critical limitation,and conventional flame-retardant strategies often compromise their mechanical properties,hindering their practical applications.Herein,a 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide(DOPO)-based comonomer(DDP)was used to synthesize flame-retardant poly(ethylene furandicarboxylate-co-phosphaphenanthrene)(PEFDn).The covalent integration of DDP confers intrinsic flame retardancy,avoiding the plasticization and migration issues associated with additive-type systems.Upon thermal decomposition,the DOPO-derived moieties release phosphoric acid and radical scavengers,promoting char formation and suppressing flame propagation.Furthermore,density functional theory(DFT)calculations combined with non-covalent interaction(NCI)analysis revealed that DOPO dimer molecules adopt a stable parallel-displaced π-π stacking configu ration,potentially facilitating microphase separation and enhancing the energy dissipation capability.PEFD_(10)achieves a UL-94 V-0 rating while simultaneously increasing impact toughness from 1.5 kJ/m^(2) to 14.7 kJ/m^(2).Im portantly,PEFDn maintained acceptable oxygen-barrier properties.PEFD10 also exhibited high transparency and UV-shielding performance.The combination of intrinsic flame safety,im pact-toughness resistance,UV shielding,and an oxygen barrier ensures reliable protection of electrical components and long-term operational stability.The integration of multiple critical properties within a single bio-based material represents a novel approach fo r enabling sustainable polymer solutions for high-pe rformance electrical applications.展开更多
Poly(phenylene oxide)(PPO)exhibits excellent dielectric properties,making it an ideal substrate for high-frequency,high-speed copper-clad laminates.The phenolic hydroxyl group at the end of PPO plays a key role in its...Poly(phenylene oxide)(PPO)exhibits excellent dielectric properties,making it an ideal substrate for high-frequency,high-speed copper-clad laminates.The phenolic hydroxyl group at the end of PPO plays a key role in its reactivity.Accurately quantifying the phenolic hydroxyl content in PPO is essential but challenging.In this study,we proposed a method for measuring the phenolic hydroxyl content of PPO using differential UV absorption spectroscopy.In alkaline solutions,the phenolic hydroxyl in PPO completely ionizes to form phenoxide ions,leading to a significant increase in UV absorbance at approximately 250 and 300 nm.Notably,the differential UV absorbance at approximately 300 nm was directly proportional to the phenolic hydroxyl concentration.Using 2,6-dimethylphenol as a standard,a calibration curve was established to relate the phenolic hydroxyl concentration to differential UV absorbance at approximately 300 nm,providing a precise and straightforward method for phenolic hydroxyl quantification in PPO with distinct advantages over conventional techniques.展开更多
Although the efficiency of poly(ethylene terephthalate)(PET)degradation has been successfully improved by depolymerase engineering,mostly by using Goodfellow-PET(gf-PET)as a substrate,efforts to degrade unpretreated P...Although the efficiency of poly(ethylene terephthalate)(PET)degradation has been successfully improved by depolymerase engineering,mostly by using Goodfellow-PET(gf-PET)as a substrate,efforts to degrade unpretreated PET materials with high crystallinity remain insufficient.Here,we endeavored to improve the degradation capability of a WCCG mutant of leaf-branch compost cutinase(LCC)on a unpretreated PET substrate(crystallinity>40%)by employing iterative saturation mutagenesis.Using this method,we developed a high-throughput screening strategy appropriate for unpretreated substrates.Through extensive screening of residues around the substrate-binding groove,two variants,WCCG-sup1 and WCCG-sup2,showed good depolymerization capabilities with both high-(42%)and low-crystallinity(9%)substrates.The WCCG-sup1 variant completely depolymerized a commercial unpretreated PET product in 36 h at 72℃.In addition to enzyme thermostability and catalytic efficiency,the adsorption of enzymes onto substrates plays an important role in PET degradation.This study provides valuable insights into the structure-function relationship of LCC.展开更多
Polymers that exhibit both biodegradability and chemical recyclability offer a promising solution to environmental pollution and resource scarcity. Poly(glycolic acid)(PGA) is a promising chemically recyclable polymer...Polymers that exhibit both biodegradability and chemical recyclability offer a promising solution to environmental pollution and resource scarcity. Poly(glycolic acid)(PGA) is a promising chemically recyclable polymer, characterized by its seawater degradability and high mechanical strength. In this study, aliphatic polycarbonates were synthesized through melt polycondensation and subsequently copolymerized with glycolide(GL) to produce chemically recyclable PGA based triblock copolymers with well-defined structures. The properties of these copolymers, including their thermal properties, crystallization behavior, and mechanical performance, can be effectively adjusted by modifying the structure and content of the middle block. Furthermore, an in-depth investigation reveals that the pyrolysis process involves ester exchange, radical, and back-biting reactions. In addition, the high-efficiency "Monomer↔Copolymer" chemical recycling loop has been established, achieving a remarkable yield exceeding 88% along with a purity greater than 99%.展开更多
Conventional liquid electrolytes in lithium-ion batteries(LIBs)pose significant safety risks and interfacial instability,hindering the development of high-energy-density systems.Solid polymer electrolytes(SPEs),partic...Conventional liquid electrolytes in lithium-ion batteries(LIBs)pose significant safety risks and interfacial instability,hindering the development of high-energy-density systems.Solid polymer electrolytes(SPEs),particularly polyethylene oxide(PEO)-based systems,offer enhanced safety but suffer from low room-temperature ionic conductivity due to high crystallinity,alongside limitations such as poor lithium-ion transference numbers and dendrite growth.To address these challenges,this study develops a novel composite solid electrolyte(PSPH)by synthesizing a polystyrene-polyethylene oxide-polystyrene(PSPEO-PS)triblock copolymer and blending it with poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)and lithium bis(trifluoromethylsulfonyl)imide(LiTFSI).The rigid PS segments suppress PEO crystallization,while PVDF-HFP enhances amorphous domain content,promotes LiTFSI dissociation via its high dielectric constant,and improves mechanical strength.The optimized PSPH composition(M_(w,PEO)=35 kg·mol^(-1),w_(PS)=15%,w_(PVDF-HFP)=30%)exhibits a high ionic conductivity of 1.05×10^(-4) S·cm^(-1)at 25℃,a Li^(+)transference number of 0.46,and an extended electrochemical stability window up to 4.8 V.PSPH demonstrates excellent thermal stability(decomposition onset at about 340℃),flexibility,and interfacial compatibility.LiFePO_(4)/PSPH/Li cells delivere a high discharge capacity of 163.7 mAh·g^(-1) at 0.1 C,with 96.2%capacity retention and 99.83%average coulombic efficiency after 200 cycles.Furthermore,Li/PSPH/Li symmetric cells exhibit stable cycling for over 1500 h at 0.05 mA·cm^(-2) with low overpotential(about 0.15 V).These results demonstrate that PSPH is a highly promising electrolyte for enhancing the safety and electrochemical performance of all-solid-state lithium-metal batteries(LMBs).展开更多
The synthesis of polyurethanes(PUs)from the reaction of low molecular weight poly(ethylene carbonate)diol(PECD)is rarely investigated.This work reports a novel PU with excellent mechanical properties from the solution...The synthesis of polyurethanes(PUs)from the reaction of low molecular weight poly(ethylene carbonate)diol(PECD)is rarely investigated.This work reports a novel PU with excellent mechanical properties from the solution polymerization of 4,4-diphenylmethane diisocyanate(MDI)with PECD that was derived from the copolymerization of carbon dioxide(CO_(2))and ethylene oxide(EO).The tensile strength,the elongation at break and 300%constant tensile strength of the PECD-PU were up to 66±2 MPa,880%±50%and 13 MPa,respectively,higher than the control PUs from the reaction of MDI with commercial polyethers or polyesters.The PECD-PU with high CO_(2) carbonate content exhibited good solvent resistance and chemical stability.Of importance,the mechanical properties and chemical resistance of PECD-PU were significantly enhanced with the increasing content of CO_(2),i.e.,the carbonate unit in PECD.This work provides comprehensive properties of PECD-derived PUs,indicating that PECD is a competitive precursor for the preparation of PU and has broad application prospects.展开更多
It is well known that cationic polymers have excellent antimicrobial capacity accompanied with high biotoxicity,to reduce biotoxicity needs to decrease the number of cationic groups on polymers,which will influence an...It is well known that cationic polymers have excellent antimicrobial capacity accompanied with high biotoxicity,to reduce biotoxicity needs to decrease the number of cationic groups on polymers,which will influence antimicrobial activity.It is necessary to design a cationic polymer mimic natural antimicrobial peptide with excellent antibacterial activity and low toxicity to solve the above dilemma.Here,we designed and prepared a series of cationic poly(β-amino ester)s(PBAEs)with different cationic contents,and introducing hydrophobic alkyl chain to adjust the balance between antimicrobial activity and biotoxicity to obtain an ideal antimicrobial polymer.The optimum one of synthesized PBAE(hydrophilic cationic monomer:hydrophobic monomer=5:5)was screened by testing cytotoxicity and minimum inhibitory concentration(MIC),which can effectively kill S.aureus and E.coli with PBAE concentration of15μg/m L by a spread plate bacteriostatic method and dead and alive staining test.The way of PBAE killing bacterial was destroying the membrane like natural antimicrobial peptide observed by scanning electron microscopy(SEM).In addition,PBAE did not exhibit hemolysis and cytotoxicity.In particular,from the result of animal tests,the PBAE was able to promote healing of infected wounds from removing mature S.aureus and E.coli on the surface of infected wound.As a result,our work offers a viable approach for designing antimicrobial materials,highlighting the significant potential of PBAE polymers in the field of biomedical materials.展开更多
The continuous improvement in patient care and recovery is driving the development of innovative materials for medical applications.Medical sutures,essential for securing implants and closing deep wounds,have evolved ...The continuous improvement in patient care and recovery is driving the development of innovative materials for medical applications.Medical sutures,essential for securing implants and closing deep wounds,have evolved to incorporate smart materials capable of responding to various stimuli.This study explores the potential of thermoresponsive sutures,made from shape memory materials,that contract upon heating to bring loose stitches closer together,promoting optimal wound closure.We developed nanocomposites based on a blend of poly(lactic acid)(PLA)and thermoplastic polyurethane(TPU)—biopolymers that inherently exhibit shape memory—enhanced with carbon nanotubes(CNT)and graphene nanoplatelets(GN)to improve mechanical performance.PLA/TPU(50/50)nanocomposites were prepared with 1 and 2 wt%GN,as well as hybrid formulations combining 1 wt%CNT with 1 or 2 wt%GN,using a twin-screw extrusion process to form filaments.These filaments were characterized through differential scanning calorimetry(DSC),field emission gun scanning electron microscopy(FEG-SEM),tensile testing,and shape memory assessments.While the PLA/TPU blend is immiscible,TPU enhances the crystallinity(X_(c))of the PLA phase,further increased by the addition of CNT and GN.FEG-SEM images indicate CNTs primarily in the PLA phase and GN in the TPU phase.PLA/TPU with 1 or 2 wt%GN showed the highest potential for suture applications,with a high elastic modulus(~1000 MPa),significant strain at break(~10%),and effective shape recovery(~20%at 55℃ for 30 min).These findings suggest that these nanocomposites can enhance suture performance with controlled shape recovery that is suitable for medical use.展开更多
Poly(ethylene 2,5-furandicarboxylate)(PEF),a bioplastic synthesized via the polymerization of 2,5-furandicarboxylic acid(FDCA)with ethylene glycol,can be served as a substitute to petroleum-based polyethylene terephth...Poly(ethylene 2,5-furandicarboxylate)(PEF),a bioplastic synthesized via the polymerization of 2,5-furandicarboxylic acid(FDCA)with ethylene glycol,can be served as a substitute to petroleum-based polyethylene terephthalate(PET)due to its enhanced material properties.However,the fabrication of PEF with stable and desirable properties is still a challenge,largely due to the impurities in FDCA.In this study,a highly efficient purification strategy for FDCA was proposed,utilizing a dioxane/H_(2)O binary solvent system for effective crystallization.Furthermore,PEFs were synthesized from FDCA with varying impurity and the effects of these impurities were systematically characterized.The results revealed that impurities in FDCA could result in PEFs with relatively poor thermal properties.This study provides crucial insights for the impact of impurities on PEF properties and FDCA purification.展开更多
The sulfonated poly(α-methyl styrene-b-isobutylene-b-α-methyl styrene)copolymers(S-ASIBS)with the average molar percentage of sulfonic acid(-SO_(3)H)groups(SP)ranging from 3.6 mol%to 14.3 mol%could be synthesized by...The sulfonated poly(α-methyl styrene-b-isobutylene-b-α-methyl styrene)copolymers(S-ASIBS)with the average molar percentage of sulfonic acid(-SO_(3)H)groups(SP)ranging from 3.6 mol%to 14.3 mol%could be synthesized by sulfonation of ASIBS with acetyl sulfate.The hydrophilic ionic channels were generated for proton exchange membranes(PEMs)by ion aggregation of-SO_(3)H groups and microphase separation between hydrophobic polyisobutylene and hydrophilic sulfonated poly(α-methyl styrene)segments in S-ASIBS.The proton transport ability was improved while oxidative stability was decreased by increasing SP in S-ASIBS.The appropriate SP of about 12.7 mol%in S-ASIBS provides the available PEMs with high proton transport ability,low methanol permeability and good oxidative stability.The absence of active tertiary hydrogen atoms along S-ASIBS copolymer chains avoids their attack by peroxy radicals.The residual rates of weight(RW)and proton conductivity(Rσ)of S-ASIBS-12.7 membrane after oxidation treatment for 916 h were 84.3%and 88.1%respectively,near to those of commercial Nafion 117(RW=87.9%,Rσ=90.3%).The membrane electrode assembly(MEA)could be prepared by using various S-ASIBS as PEMs for direct methanol fuel cell.The single cell with S-ASIBS-12.7 MEA behaves high performance of open circuit voltage(OCV)of 548 mV and peak power density(Pmax)of 36.1 mW·cm^(-2),which is similar to those of Nafion 117(OCV=506 mV,P_(max)=35.6 mW·cm^(-2)).To the best of our knowledge,this is the first example of advanced S-ASIBS membrane with high proton conductivity,excellent fuel barrier property and remarkable oxidative stability for promising PEMs.展开更多
Compatibilization is crucial for the blending of immiscible polymers to develop high-performance composites;however,traditional compatibilization by copolymers(pre-made or in-situ generation)suffers from weak interfac...Compatibilization is crucial for the blending of immiscible polymers to develop high-performance composites;however,traditional compatibilization by copolymers(pre-made or in-situ generation)suffers from weak interface anchoring,and inorganic particles have gained extensive attention recently owing to their large interfacial desorption energy,while their low affinity to bulk components is a drawback.In this study,an interfacial atom transfer radical polymerization(ATRP)technique was employed to grow polystyrene(PS)and poly(2-hydroxyethyl methacrylate)(PHEMA)simultaneously on different hemispheres of Br-functionalized SiO_(2) nanoparticles to stabilize a Pickering emulsion,whereby a brush-type Janus nanoparticle(SiO_(2)@JNP)was developed.The polymer brushes were well-characterized,and the Janus feature was validated by transmission electron microscope(TEM)observation of the sole hemisphere grafting of SiO_(2)-PS as a control sample.SiO_(2)@JNP was demonstrated to be an efficient compatibilizer for a PS/poly(methyl methacrylate)(PMMA)immiscible blend,and the droplet-matrix morphology was significantly refined.The mechanical strength and toughness of the blend were synchronously enhanced at a low content SiO_(2)@JNP optimized~0.9 wt%,with the tensile strength,elongation at break and impact strength increased by 17.7%,26.6%and 19.6%,respectively.This enhancement may be attributed to the entanglements between the grafted polymer brushes and individual components that improve the particle-bulk phase affinity and enforce interfacial adhesion.展开更多
The use of biomass feedstocks for the manufacture of high-performance polymers can help expand their range of applications and reduce their dependence on finite fossil resources.However,improving the heat resistance a...The use of biomass feedstocks for the manufacture of high-performance polymers can help expand their range of applications and reduce their dependence on finite fossil resources.However,improving the heat resistance and hydrophilicity of bio-based polyesters remains a significant challenge.Herein,we introduce N,N'-trans-1,4-cyclohexane-bis(pyrrolidone-4-methylcarboxylate)(CBPC),a novel bio-based tricyclic dibasic ester synthesized from renewable dimethyl itaconic acid and trans-1,4-cyclohexane diamine via an aza-Michael addition reaction.As a unique comonomer,CBPC features a rigid tricyclic backbone that significantly enhances chain packing and thermal stability,whereas its pyrrolidone side groups impart tunable polarity and improved hydrophilicity.Using CBPC,diphenyl carbonate,and 1,4-butylene glycol,a series of PBCC copolymers with 10 mol%-30 mol%CBPC was synthesized via ester-exchange and melt polycondensation methods.Incorporation of CBPC raised the melting temperature(Tm)from 56.8℃to 225.8℃and the initial decomposition temperature(Td5%)from 258.0℃to 306.7℃,positioning PBCC among the most heat-resistant bio-based polyesters reported.Additionally,the pyrrolidone units enabled transformation from hydrophobic to hydrophilic.This study demonstrates that CBPC is an effective and innovative building block for the design of bio-based polymers with enhanced thermal and surface properties,offering a promising strategy for the development of high-performance sustainable materials.展开更多
Sodium metal batteries(SMBs)represent a promising alternative for large-scale energy storage and lowspeed electric vehicles,with resource-sustainable and cost-effective characteristics.However,its practical applicatio...Sodium metal batteries(SMBs)represent a promising alternative for large-scale energy storage and lowspeed electric vehicles,with resource-sustainable and cost-effective characteristics.However,its practical application is hindered by the high reactivity of sodium metal,interfacial and structural instability,and fire safety risks.Herein,a poly(1,3-dioxolane)(PDOL)crosslinked quasi-solid-state electrolyte(TPQSE)with fire extinguishing property and superior interface compatibility with sodium(Na)anodes and Na_(3)V_(2)(PO_(4))_(3)(NVP)cathodes is prepared via in situ polymerization at room temperature(RT),utilizing trimethylolpropane triglycidyl ether(TTE)as a crosslinker in coordination with ethoxy(pentafluoro)cyclotriphosphazene(PFPN).The crosslinked network of TPQSE and the distinct solvation properties of TPDOL and PFPN facilitate Na-ion desolvation while enhancing antioxidant stability of TPQSE.Moreover,multifunctional PFPN improves fire safety through condensed-phase dense char layer formation and gas-phase free radical capturing.It also constructs uniform,dense,and inorganic-rich interphases between electrodes and electrolytes,strengthening interfacial stability.Consequently,the prepared electrolyte exhibits high ionic conductivity(2.109 mS cm^(-1)at RT),high Na^(+)transference number(0.570),and extended electrochemical window to 4.805 V.The Na‖TPQSE‖Na symmetric cell presents impressive cycling stability over 4510 h,and the Na‖TPQSE‖NVP cell displays outstanding rate capability and stable long-term cycling(≥2300 cycles).This work provides a promising approach for developing safe and high-performance quasi-solid-state sodium metal batteries.展开更多
Most commercial plastics cannot easily degrade,which raises a number of sustainability issues.To address the current problem of plastic pollution,the research and development of easily degradable and recyclable polyme...Most commercial plastics cannot easily degrade,which raises a number of sustainability issues.To address the current problem of plastic pollution,the research and development of easily degradable and recyclable polymers has become an attractive subject.Herein,a new monomer of thiosalicylic methyl glycolide(TSMG)was synthesized using one-pot method and high molecular weight poly(thiosalicylic methyl glycolide)(PTSMG,M_(n) up to 300 kDa)can be obtained via the ring-opening polymerization(ROP)of TSMG.PTSMG exhibits good closed-loop recyclability and hydrolytic degradability,where PTSMG can generate pristine monomers through sublimation thermal depolymerization conditions due to the presence of thiophenol ester bond in the polymer chains,and can be degraded rapidly in aqueous solution,which provides a potential solution to the current plastic pollution problem.展开更多
Herein,a simple method for preparing poly(vinylidene fluoride)(PVDF)films with controlledβ/γratios by spin-coating assisted by potassium bromide(KBr)is proposed.The results show that the relative fraction of theβph...Herein,a simple method for preparing poly(vinylidene fluoride)(PVDF)films with controlledβ/γratios by spin-coating assisted by potassium bromide(KBr)is proposed.The results show that the relative fraction of theβphase(denoted as Fβ)for the films prepared on the KBr surface first decreased until a critical temperature(denoted as Tc)was reached,and then increased with increasing spin-coating temperature.This was related to the dissolved K and Br ions in the films.Further experiments showed that below Tc,high humidity can enhance Fβbut exhibit an adverse effect at and above Tc.The high content of K and Br ions in the PVDF/KBr blend film and larger shear stress can facilitate the formation of theβphase,leading exclusively to the formation ofβ-andγ-phases.The mechanism responsible for the change in Fβwith temperature was proposed:below Tc,the decrease in water intake with increasing temperature results in the decline of Fβ,whereas above Tc,the increase in Fβwith temperature is attributed to the synergistic effect of ions and shear stress.Ultimately,this paves the way for fabricating PVDF films with tailoredβ/γratios for electroactive and energy-harvesting applications.展开更多
Considering large volume variation and dissolution issues of some promising electrode materials for chloride ion batteries(CIB),the construction of solid polymer electrolytes(SPE)for efficient chloride ion transport i...Considering large volume variation and dissolution issues of some promising electrode materials for chloride ion batteries(CIB),the construction of solid polymer electrolytes(SPE)for efficient chloride ion transport is intriguing.However,this is hindered by low ionic conductivity of chloride SPEs and poor cycling performance of CIBs.Herein,an in-situ polymerized and cross-linked poly(ethylene gly-col)diacrylate-based chloride SPE with a low plasticizer content of succinonitrile is designed,yielding a room-temperature ionic conductivity of 7.6×10^(−5) S cm^(−1),which is higher than that of previously re-ported SPEs for CIBs.Moreover,the use of the asprepared SPE achieves an integrated organic cathode with significantly enhanced rate performance and capacity retention of 96.1%after 100 cycles at room temperature,which is much higher than 49.9%(80 cycles)of the cathode in the CIB with a sandwiched structure.These improved properties are also superior to that of other reported cathodes coupled with different chloride SPEs.The chloride ion transfer mechanism of the cathode is revealed by X-ray photo-electron spectroscopy and energy dispersive spectroscopy.展开更多
基金financially supported by the Jiangsu Forestry Science and Technology Innovation and Promotion Project(No.LYKJ-Nanjing[2022]02)the Jiangsu Agricultural Science and Technology Innovation Fund(No.CX(23)3090)。
文摘Smart pesticide delivery systems based on stimuli-responsive nanocarriers have attracted considerable attention because of their potential to enhance pesticide efficiency while reducing environmental risks.In this study,a novel p H/glutathione dual-responsive pesticide delivery system was constructed through the synthesis of disulfide-bridged hollow mesoporous organosilica nanospheres(HMONs)via the St??ber method,followed by poly(acrylic acid)(PAA)coating through distillation-precipitation polymerization to form HMONs@PAA nanocomposites.The resulting abamectin-loaded system(Abamectin-HMONs@PAA)demonstrated a 12.73% pesticide loading capacity and significantly improved photostability,retaining twice as much active ingredient as free abamectin after 250 h of UV irradiation(36 W).Release studies revealed p H-and glutathione-dependent characteristics,with cumulative releases in acidic conditions exceeding those in neutral and alkaline environments by 18.66% and 40.98%,respectively,and a 14.2% increase in glutathione-containing solution(0.2 mmol·L^(-1) in 70% ethanol)after 97 h.Bioassays showed superior performance against Plutella xylostella,with a 13.33% reduction in survival rate compared to conventional suspension at equivalent dosage(40 mg·L^(-1)),while maintaining efficacy after extensive rainfall simulation(20 events over 10 days).This study provides a promising approach for developing environmentally responsive nanopesticides with enhanced durability and controlled-release properties,offering significant potential for sustainable crop protection.
文摘Herein,manganese(Mn)‑doped poly(1,5‑diaminonaphthalene)(PN)electrode material(Mn@PN)was synthesized via chemical oxidative polymerization.The material′s distinctive vesicular architecture enables rapid ion transport while maintaining the structural stability of the electrode under continuous charge‑discharge cycles.Electrochemical characterization under a three‑electrode system revealed exceptional rate capability:Mn@PN delivered an ultrahigh specific capacitance of 10318 F·g^(-1) at a low current density of 3 A·g^(-1) and retained 9415 F·g^(-1)(91.2%retention compared to the value at 3 A·g^(-1))even at an ultrahigh current density of 50 A·g^(-1).Moreover,the material exhibited 97.4%capacitance retention after 9000 cycles at 30 A·g^(-1),corresponding with a low capacitance decay rate of 0.003‰per cycle,significantly outperforming conventional conductive polymers like polyaniline(PANI).An asymmetric supercapacitor assembled with Mn@PN as the positive electrode(Mn@PN||AC)achieved an energy density of 328 Wh·kg^(-1) at 15 A·g^(-1) and retained 80.7%of its initial specific capacitance after 4000 cycles at 20 A·g^(-1).
基金financially supported by the National Natural Science Foundation of China(Nos.22271252 and 22201105)。
文摘Consisting of natural histidine residues,polyhistidine(PHis)simulates functional proteins.Traditional approaches towards PHis require the protection of imidazole groups before monomer synthesis and polymerization to prevent degradation and side reactions.In the contribution,histidine N-thiocarboxyanhydride(His-NTA)is directly synthesized in aqueous solution without protection.With the self-catalysis of the imidazole side group,the ring-closing reaction to form His-NTA does not require any activating reagent(e.g.,phosphorus tribromide),which is elucidated by density functional theory(DFT)calculations.His-NTA directly polymerizes into PHis bearing unprotected imidazole groups with designable molecular weights(4.2-7.7 kg/mol)and low dispersities(1.10-1.19).Kinetic experiments and Monte Carlo simulations reveal the elementary reactions and the relationship between the conversion of His-NTA and time during polymerization.Block copolymerization of His-NTA with sarcosine N-thiocarboxyanhydride(Sar-NTA)demonstrate versatile construction of functional polypept(o)ides.The triblock copoly(amino acid)PHis-b-PSar-b-PHis is capable to reversibly coordinate with transition metal ions(Fe^(2+),Co^(2+),Ni^(2+),Cu^(2+)and Zn^(2+))to form pH-sensitive hydrogels.
基金the financial support from the National Natural Science Foundation of China(No.52072390)the National High-Level Talents Special Support Program(Leading Talent of Technological Innovation),the China Postdoctoral Science Foundation(No.2023M743648)the Young Scientists Fund of the National Natural Science Foundation of China(No.52302330).We also gratefully appreciate the support from the Shanghai Emperor of Cleaning Hi-Tech Co.,LTD.
文摘In-situ poly(1,3-dioxolane)(PDOL)-based electrolyte has received extensive attention in the research of lithium metal batteries due to its high stability to lithium anode and simple processing.However,it is still faced with defects such as low intrinsic ionic conductivity,a narrow electrochemical window,and poor thermal stability.A crosslinking and fluorination molecular design strategy toward PDOL is proposed to tackle the issues above.The amorphous crosslinked structure effectively improves ionic conductivity by inhibiting long-chain crystallization.Especially,the antioxidant–CF_(3)groups,stable crosslinked structure,and reduced terminal hydroxyl groups significantly enhance the electrochemical oxidation stability with a superb high-voltage window of 4.7 V.In addition,the designed electrolyte also exhibits obviously improved thermal stability with no deformation at 120°C for 5 min.Furthermore,the semi-solid NCM811||Li batteries exhibit a favourable capacity retention of 88.8%after 150 cycles at 0.5 C.Even assembled with NCM622 cathode working at 4.5 V,the semi-solid batteries can still show a satisfactory capacity retention of 85.3%after 100 cycles at 0.5 C.Also,a 0.1 Ah NCM811||Li pouch cell with active materials loading of 9 mg/cm2 demonstrates satisfactory cycling stability and working ability,which shows promising practical application prospects.
基金financially supported by the National Key Research and Development Program of China(No.2021YFB3700300)the National Natural Science Foundation of China(Nos.52573017 and U21B2093)+1 种基金Key Research and Development Program of Ningbo(No.2022Z200)the Zhejiang Provincial Natural Science Foundation(No.LY23E030005)。
文摘Bio-based 2,5-furandicarboxylic acid polyesters offer significant promise for reducing energy and environmental crises.However,their intrinsic flammability remains a critical limitation,and conventional flame-retardant strategies often compromise their mechanical properties,hindering their practical applications.Herein,a 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide(DOPO)-based comonomer(DDP)was used to synthesize flame-retardant poly(ethylene furandicarboxylate-co-phosphaphenanthrene)(PEFDn).The covalent integration of DDP confers intrinsic flame retardancy,avoiding the plasticization and migration issues associated with additive-type systems.Upon thermal decomposition,the DOPO-derived moieties release phosphoric acid and radical scavengers,promoting char formation and suppressing flame propagation.Furthermore,density functional theory(DFT)calculations combined with non-covalent interaction(NCI)analysis revealed that DOPO dimer molecules adopt a stable parallel-displaced π-π stacking configu ration,potentially facilitating microphase separation and enhancing the energy dissipation capability.PEFD_(10)achieves a UL-94 V-0 rating while simultaneously increasing impact toughness from 1.5 kJ/m^(2) to 14.7 kJ/m^(2).Im portantly,PEFDn maintained acceptable oxygen-barrier properties.PEFD10 also exhibited high transparency and UV-shielding performance.The combination of intrinsic flame safety,im pact-toughness resistance,UV shielding,and an oxygen barrier ensures reliable protection of electrical components and long-term operational stability.The integration of multiple critical properties within a single bio-based material represents a novel approach fo r enabling sustainable polymer solutions for high-pe rformance electrical applications.
基金the“Pioneer”and“Leading Goose”R&D Program of Zhejiang(No.2023C01072)the Institute of Zhejiang University-Quzhou for their financial support。
文摘Poly(phenylene oxide)(PPO)exhibits excellent dielectric properties,making it an ideal substrate for high-frequency,high-speed copper-clad laminates.The phenolic hydroxyl group at the end of PPO plays a key role in its reactivity.Accurately quantifying the phenolic hydroxyl content in PPO is essential but challenging.In this study,we proposed a method for measuring the phenolic hydroxyl content of PPO using differential UV absorption spectroscopy.In alkaline solutions,the phenolic hydroxyl in PPO completely ionizes to form phenoxide ions,leading to a significant increase in UV absorbance at approximately 250 and 300 nm.Notably,the differential UV absorbance at approximately 300 nm was directly proportional to the phenolic hydroxyl concentration.Using 2,6-dimethylphenol as a standard,a calibration curve was established to relate the phenolic hydroxyl concentration to differential UV absorbance at approximately 300 nm,providing a precise and straightforward method for phenolic hydroxyl quantification in PPO with distinct advantages over conventional techniques.
文摘Although the efficiency of poly(ethylene terephthalate)(PET)degradation has been successfully improved by depolymerase engineering,mostly by using Goodfellow-PET(gf-PET)as a substrate,efforts to degrade unpretreated PET materials with high crystallinity remain insufficient.Here,we endeavored to improve the degradation capability of a WCCG mutant of leaf-branch compost cutinase(LCC)on a unpretreated PET substrate(crystallinity>40%)by employing iterative saturation mutagenesis.Using this method,we developed a high-throughput screening strategy appropriate for unpretreated substrates.Through extensive screening of residues around the substrate-binding groove,two variants,WCCG-sup1 and WCCG-sup2,showed good depolymerization capabilities with both high-(42%)and low-crystallinity(9%)substrates.The WCCG-sup1 variant completely depolymerized a commercial unpretreated PET product in 36 h at 72℃.In addition to enzyme thermostability and catalytic efficiency,the adsorption of enzymes onto substrates plays an important role in PET degradation.This study provides valuable insights into the structure-function relationship of LCC.
基金financially supported by the National Key R&D Program of China(No.2021YFB3801901)the Institutional Research Fund from Sichuan University(No.2020SCUNL205)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Higher Education Discipline Innovation Project(No.B20001)。
文摘Polymers that exhibit both biodegradability and chemical recyclability offer a promising solution to environmental pollution and resource scarcity. Poly(glycolic acid)(PGA) is a promising chemically recyclable polymer, characterized by its seawater degradability and high mechanical strength. In this study, aliphatic polycarbonates were synthesized through melt polycondensation and subsequently copolymerized with glycolide(GL) to produce chemically recyclable PGA based triblock copolymers with well-defined structures. The properties of these copolymers, including their thermal properties, crystallization behavior, and mechanical performance, can be effectively adjusted by modifying the structure and content of the middle block. Furthermore, an in-depth investigation reveals that the pyrolysis process involves ester exchange, radical, and back-biting reactions. In addition, the high-efficiency "Monomer↔Copolymer" chemical recycling loop has been established, achieving a remarkable yield exceeding 88% along with a purity greater than 99%.
基金supported by the 2024 Capital Construction Funds within the Provincial Budget of Jilin Provincial Development and Reform Commission[2024C018-2].
文摘Conventional liquid electrolytes in lithium-ion batteries(LIBs)pose significant safety risks and interfacial instability,hindering the development of high-energy-density systems.Solid polymer electrolytes(SPEs),particularly polyethylene oxide(PEO)-based systems,offer enhanced safety but suffer from low room-temperature ionic conductivity due to high crystallinity,alongside limitations such as poor lithium-ion transference numbers and dendrite growth.To address these challenges,this study develops a novel composite solid electrolyte(PSPH)by synthesizing a polystyrene-polyethylene oxide-polystyrene(PSPEO-PS)triblock copolymer and blending it with poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)and lithium bis(trifluoromethylsulfonyl)imide(LiTFSI).The rigid PS segments suppress PEO crystallization,while PVDF-HFP enhances amorphous domain content,promotes LiTFSI dissociation via its high dielectric constant,and improves mechanical strength.The optimized PSPH composition(M_(w,PEO)=35 kg·mol^(-1),w_(PS)=15%,w_(PVDF-HFP)=30%)exhibits a high ionic conductivity of 1.05×10^(-4) S·cm^(-1)at 25℃,a Li^(+)transference number of 0.46,and an extended electrochemical stability window up to 4.8 V.PSPH demonstrates excellent thermal stability(decomposition onset at about 340℃),flexibility,and interfacial compatibility.LiFePO_(4)/PSPH/Li cells delivere a high discharge capacity of 163.7 mAh·g^(-1) at 0.1 C,with 96.2%capacity retention and 99.83%average coulombic efficiency after 200 cycles.Furthermore,Li/PSPH/Li symmetric cells exhibit stable cycling for over 1500 h at 0.05 mA·cm^(-2) with low overpotential(about 0.15 V).These results demonstrate that PSPH is a highly promising electrolyte for enhancing the safety and electrochemical performance of all-solid-state lithium-metal batteries(LMBs).
基金financially supported by the Maoming Science and Technology Bureau(No.2022DZXHT007)。
文摘The synthesis of polyurethanes(PUs)from the reaction of low molecular weight poly(ethylene carbonate)diol(PECD)is rarely investigated.This work reports a novel PU with excellent mechanical properties from the solution polymerization of 4,4-diphenylmethane diisocyanate(MDI)with PECD that was derived from the copolymerization of carbon dioxide(CO_(2))and ethylene oxide(EO).The tensile strength,the elongation at break and 300%constant tensile strength of the PECD-PU were up to 66±2 MPa,880%±50%and 13 MPa,respectively,higher than the control PUs from the reaction of MDI with commercial polyethers or polyesters.The PECD-PU with high CO_(2) carbonate content exhibited good solvent resistance and chemical stability.Of importance,the mechanical properties and chemical resistance of PECD-PU were significantly enhanced with the increasing content of CO_(2),i.e.,the carbonate unit in PECD.This work provides comprehensive properties of PECD-derived PUs,indicating that PECD is a competitive precursor for the preparation of PU and has broad application prospects.
基金financially supported by the Natural Science Foundation of Jilin Province Science and Technology Department(No.20230101221JC)the National Natural Science Foundation of China(Nos.52173115,52073278,52203189)the Research Foundation for Advanced Talents of Xiamen University of Technology(Nos.5010423019,YKJ22052R)。
文摘It is well known that cationic polymers have excellent antimicrobial capacity accompanied with high biotoxicity,to reduce biotoxicity needs to decrease the number of cationic groups on polymers,which will influence antimicrobial activity.It is necessary to design a cationic polymer mimic natural antimicrobial peptide with excellent antibacterial activity and low toxicity to solve the above dilemma.Here,we designed and prepared a series of cationic poly(β-amino ester)s(PBAEs)with different cationic contents,and introducing hydrophobic alkyl chain to adjust the balance between antimicrobial activity and biotoxicity to obtain an ideal antimicrobial polymer.The optimum one of synthesized PBAE(hydrophilic cationic monomer:hydrophobic monomer=5:5)was screened by testing cytotoxicity and minimum inhibitory concentration(MIC),which can effectively kill S.aureus and E.coli with PBAE concentration of15μg/m L by a spread plate bacteriostatic method and dead and alive staining test.The way of PBAE killing bacterial was destroying the membrane like natural antimicrobial peptide observed by scanning electron microscopy(SEM).In addition,PBAE did not exhibit hemolysis and cytotoxicity.In particular,from the result of animal tests,the PBAE was able to promote healing of infected wounds from removing mature S.aureus and E.coli on the surface of infected wound.As a result,our work offers a viable approach for designing antimicrobial materials,highlighting the significant potential of PBAE polymers in the field of biomedical materials.
基金This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoalde Nível Superior-Brasil(CAPES)-Finance Code 001.
文摘The continuous improvement in patient care and recovery is driving the development of innovative materials for medical applications.Medical sutures,essential for securing implants and closing deep wounds,have evolved to incorporate smart materials capable of responding to various stimuli.This study explores the potential of thermoresponsive sutures,made from shape memory materials,that contract upon heating to bring loose stitches closer together,promoting optimal wound closure.We developed nanocomposites based on a blend of poly(lactic acid)(PLA)and thermoplastic polyurethane(TPU)—biopolymers that inherently exhibit shape memory—enhanced with carbon nanotubes(CNT)and graphene nanoplatelets(GN)to improve mechanical performance.PLA/TPU(50/50)nanocomposites were prepared with 1 and 2 wt%GN,as well as hybrid formulations combining 1 wt%CNT with 1 or 2 wt%GN,using a twin-screw extrusion process to form filaments.These filaments were characterized through differential scanning calorimetry(DSC),field emission gun scanning electron microscopy(FEG-SEM),tensile testing,and shape memory assessments.While the PLA/TPU blend is immiscible,TPU enhances the crystallinity(X_(c))of the PLA phase,further increased by the addition of CNT and GN.FEG-SEM images indicate CNTs primarily in the PLA phase and GN in the TPU phase.PLA/TPU with 1 or 2 wt%GN showed the highest potential for suture applications,with a high elastic modulus(~1000 MPa),significant strain at break(~10%),and effective shape recovery(~20%at 55℃ for 30 min).These findings suggest that these nanocomposites can enhance suture performance with controlled shape recovery that is suitable for medical use.
基金supported by the National Natural Science Foundation of China(22378338,U22A20421)the Project for Science and Technology Plan of Fujian Province of China(2024H4007)。
文摘Poly(ethylene 2,5-furandicarboxylate)(PEF),a bioplastic synthesized via the polymerization of 2,5-furandicarboxylic acid(FDCA)with ethylene glycol,can be served as a substitute to petroleum-based polyethylene terephthalate(PET)due to its enhanced material properties.However,the fabrication of PEF with stable and desirable properties is still a challenge,largely due to the impurities in FDCA.In this study,a highly efficient purification strategy for FDCA was proposed,utilizing a dioxane/H_(2)O binary solvent system for effective crystallization.Furthermore,PEFs were synthesized from FDCA with varying impurity and the effects of these impurities were systematically characterized.The results revealed that impurities in FDCA could result in PEFs with relatively poor thermal properties.This study provides crucial insights for the impact of impurities on PEF properties and FDCA purification.
基金financially supported by the National Natural Science Foundation of China (No. 21774006)
文摘The sulfonated poly(α-methyl styrene-b-isobutylene-b-α-methyl styrene)copolymers(S-ASIBS)with the average molar percentage of sulfonic acid(-SO_(3)H)groups(SP)ranging from 3.6 mol%to 14.3 mol%could be synthesized by sulfonation of ASIBS with acetyl sulfate.The hydrophilic ionic channels were generated for proton exchange membranes(PEMs)by ion aggregation of-SO_(3)H groups and microphase separation between hydrophobic polyisobutylene and hydrophilic sulfonated poly(α-methyl styrene)segments in S-ASIBS.The proton transport ability was improved while oxidative stability was decreased by increasing SP in S-ASIBS.The appropriate SP of about 12.7 mol%in S-ASIBS provides the available PEMs with high proton transport ability,low methanol permeability and good oxidative stability.The absence of active tertiary hydrogen atoms along S-ASIBS copolymer chains avoids their attack by peroxy radicals.The residual rates of weight(RW)and proton conductivity(Rσ)of S-ASIBS-12.7 membrane after oxidation treatment for 916 h were 84.3%and 88.1%respectively,near to those of commercial Nafion 117(RW=87.9%,Rσ=90.3%).The membrane electrode assembly(MEA)could be prepared by using various S-ASIBS as PEMs for direct methanol fuel cell.The single cell with S-ASIBS-12.7 MEA behaves high performance of open circuit voltage(OCV)of 548 mV and peak power density(Pmax)of 36.1 mW·cm^(-2),which is similar to those of Nafion 117(OCV=506 mV,P_(max)=35.6 mW·cm^(-2)).To the best of our knowledge,this is the first example of advanced S-ASIBS membrane with high proton conductivity,excellent fuel barrier property and remarkable oxidative stability for promising PEMs.
基金financially supported by the National Natural Science Foundation of China(Nos.22172028,21903015,and 22403017)Natural Science Foundation of Fujian Province of China(No.2022J05041)。
文摘Compatibilization is crucial for the blending of immiscible polymers to develop high-performance composites;however,traditional compatibilization by copolymers(pre-made or in-situ generation)suffers from weak interface anchoring,and inorganic particles have gained extensive attention recently owing to their large interfacial desorption energy,while their low affinity to bulk components is a drawback.In this study,an interfacial atom transfer radical polymerization(ATRP)technique was employed to grow polystyrene(PS)and poly(2-hydroxyethyl methacrylate)(PHEMA)simultaneously on different hemispheres of Br-functionalized SiO_(2) nanoparticles to stabilize a Pickering emulsion,whereby a brush-type Janus nanoparticle(SiO_(2)@JNP)was developed.The polymer brushes were well-characterized,and the Janus feature was validated by transmission electron microscope(TEM)observation of the sole hemisphere grafting of SiO_(2)-PS as a control sample.SiO_(2)@JNP was demonstrated to be an efficient compatibilizer for a PS/poly(methyl methacrylate)(PMMA)immiscible blend,and the droplet-matrix morphology was significantly refined.The mechanical strength and toughness of the blend were synchronously enhanced at a low content SiO_(2)@JNP optimized~0.9 wt%,with the tensile strength,elongation at break and impact strength increased by 17.7%,26.6%and 19.6%,respectively.This enhancement may be attributed to the entanglements between the grafted polymer brushes and individual components that improve the particle-bulk phase affinity and enforce interfacial adhesion.
基金financially supported by the Provincial Project of Science and Technology(No.2023112258)Tianshan Talent Training Program(No.2024TSYCCX0112)+1 种基金Talent Introduction and Start Foundation for Young Scientists of Shihezi University(No.2022ZK004)Program for Young Innovative Talents of Shihezi University(No.CXFZ202302)。
文摘The use of biomass feedstocks for the manufacture of high-performance polymers can help expand their range of applications and reduce their dependence on finite fossil resources.However,improving the heat resistance and hydrophilicity of bio-based polyesters remains a significant challenge.Herein,we introduce N,N'-trans-1,4-cyclohexane-bis(pyrrolidone-4-methylcarboxylate)(CBPC),a novel bio-based tricyclic dibasic ester synthesized from renewable dimethyl itaconic acid and trans-1,4-cyclohexane diamine via an aza-Michael addition reaction.As a unique comonomer,CBPC features a rigid tricyclic backbone that significantly enhances chain packing and thermal stability,whereas its pyrrolidone side groups impart tunable polarity and improved hydrophilicity.Using CBPC,diphenyl carbonate,and 1,4-butylene glycol,a series of PBCC copolymers with 10 mol%-30 mol%CBPC was synthesized via ester-exchange and melt polycondensation methods.Incorporation of CBPC raised the melting temperature(Tm)from 56.8℃to 225.8℃and the initial decomposition temperature(Td5%)from 258.0℃to 306.7℃,positioning PBCC among the most heat-resistant bio-based polyesters reported.Additionally,the pyrrolidone units enabled transformation from hydrophobic to hydrophilic.This study demonstrates that CBPC is an effective and innovative building block for the design of bio-based polymers with enhanced thermal and surface properties,offering a promising strategy for the development of high-performance sustainable materials.
基金the National Natural Science Foundation of China(52274232)the Fundamental Research Funds for the Central Universities(2024ZYGXZR016)。
文摘Sodium metal batteries(SMBs)represent a promising alternative for large-scale energy storage and lowspeed electric vehicles,with resource-sustainable and cost-effective characteristics.However,its practical application is hindered by the high reactivity of sodium metal,interfacial and structural instability,and fire safety risks.Herein,a poly(1,3-dioxolane)(PDOL)crosslinked quasi-solid-state electrolyte(TPQSE)with fire extinguishing property and superior interface compatibility with sodium(Na)anodes and Na_(3)V_(2)(PO_(4))_(3)(NVP)cathodes is prepared via in situ polymerization at room temperature(RT),utilizing trimethylolpropane triglycidyl ether(TTE)as a crosslinker in coordination with ethoxy(pentafluoro)cyclotriphosphazene(PFPN).The crosslinked network of TPQSE and the distinct solvation properties of TPDOL and PFPN facilitate Na-ion desolvation while enhancing antioxidant stability of TPQSE.Moreover,multifunctional PFPN improves fire safety through condensed-phase dense char layer formation and gas-phase free radical capturing.It also constructs uniform,dense,and inorganic-rich interphases between electrodes and electrolytes,strengthening interfacial stability.Consequently,the prepared electrolyte exhibits high ionic conductivity(2.109 mS cm^(-1)at RT),high Na^(+)transference number(0.570),and extended electrochemical window to 4.805 V.The Na‖TPQSE‖Na symmetric cell presents impressive cycling stability over 4510 h,and the Na‖TPQSE‖NVP cell displays outstanding rate capability and stable long-term cycling(≥2300 cycles).This work provides a promising approach for developing safe and high-performance quasi-solid-state sodium metal batteries.
基金supported by the National Key R&D Program of China(No.2023YFA1506804)the National Natural Science Foundation of China(Nos.22471110,22171111,22131007 and 22071093)+1 种基金the Science Foundation of Gansu Province of China(No.22JR5RA406)the Fundamental Research Funds for the Central Universities(No.lzujbky-2023-15)。
文摘Most commercial plastics cannot easily degrade,which raises a number of sustainability issues.To address the current problem of plastic pollution,the research and development of easily degradable and recyclable polymers has become an attractive subject.Herein,a new monomer of thiosalicylic methyl glycolide(TSMG)was synthesized using one-pot method and high molecular weight poly(thiosalicylic methyl glycolide)(PTSMG,M_(n) up to 300 kDa)can be obtained via the ring-opening polymerization(ROP)of TSMG.PTSMG exhibits good closed-loop recyclability and hydrolytic degradability,where PTSMG can generate pristine monomers through sublimation thermal depolymerization conditions due to the presence of thiophenol ester bond in the polymer chains,and can be degraded rapidly in aqueous solution,which provides a potential solution to the current plastic pollution problem.
基金support from the National Natural Science Foundation of China(Nos.52203026 and 52027804)。
文摘Herein,a simple method for preparing poly(vinylidene fluoride)(PVDF)films with controlledβ/γratios by spin-coating assisted by potassium bromide(KBr)is proposed.The results show that the relative fraction of theβphase(denoted as Fβ)for the films prepared on the KBr surface first decreased until a critical temperature(denoted as Tc)was reached,and then increased with increasing spin-coating temperature.This was related to the dissolved K and Br ions in the films.Further experiments showed that below Tc,high humidity can enhance Fβbut exhibit an adverse effect at and above Tc.The high content of K and Br ions in the PVDF/KBr blend film and larger shear stress can facilitate the formation of theβphase,leading exclusively to the formation ofβ-andγ-phases.The mechanism responsible for the change in Fβwith temperature was proposed:below Tc,the decrease in water intake with increasing temperature results in the decline of Fβ,whereas above Tc,the increase in Fβwith temperature is attributed to the synergistic effect of ions and shear stress.Ultimately,this paves the way for fabricating PVDF films with tailoredβ/γratios for electroactive and energy-harvesting applications.
基金supported by the National Natural Science Foundation of China(No.52222211)“333”Project of Jiangsu Province,and the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Considering large volume variation and dissolution issues of some promising electrode materials for chloride ion batteries(CIB),the construction of solid polymer electrolytes(SPE)for efficient chloride ion transport is intriguing.However,this is hindered by low ionic conductivity of chloride SPEs and poor cycling performance of CIBs.Herein,an in-situ polymerized and cross-linked poly(ethylene gly-col)diacrylate-based chloride SPE with a low plasticizer content of succinonitrile is designed,yielding a room-temperature ionic conductivity of 7.6×10^(−5) S cm^(−1),which is higher than that of previously re-ported SPEs for CIBs.Moreover,the use of the asprepared SPE achieves an integrated organic cathode with significantly enhanced rate performance and capacity retention of 96.1%after 100 cycles at room temperature,which is much higher than 49.9%(80 cycles)of the cathode in the CIB with a sandwiched structure.These improved properties are also superior to that of other reported cathodes coupled with different chloride SPEs.The chloride ion transfer mechanism of the cathode is revealed by X-ray photo-electron spectroscopy and energy dispersive spectroscopy.
