最新刊期
- 摘要：Sulfur-containing polymers possess unique physicochemical properties and diverse functionalities, making them promising candidates for applications in thermal protection, membrane separation, and precious metal recovery. Polythioimides, as a new class of sulfur-containing polymers, feature rigid molecular backbones and distinctive thioimide repeating units, and are expected to exhibit both excellent performance and rich functionalities. However, conventional synthetic methods are inadequate for the efficient preparation of high-molecular-weight polythioimides. In this work, we proposed a combined strategy of side-chain esterification and homogeneous sulfur-oxygen exchange reaction. A hydroxyl-containing soluble polyimide was used as the precursor, and low-polarity alkyl chains were introduced onto the side chains through esterification to improve the polymer solubility in weakly polar solvents such as p-xylene. Subsequently, Lawesson's reagent was employed as the thionation agent to achieve the quantitative conversion of C＝O to C＝S within the imide rings under homogeneous conditions, affording polythioimides. Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and X-ray photoelectron spectroscopy (XPS) characterizations confirmed the occurrence of near-quantitative sulfur-oxygen exchange. The resulting polythioimides exhibited good solution processability, and the glass transition temperature of the obtained films reached 230.1 ℃. Moreover, the polythioimides displayed excellent adsorption selectivity (removal efficiency: 83.6%-99.7%) toward Au3+, Pd2+ and Pt4+, as well as in situ reduction capability, enabling the formation of metal nanoparticles with small dimensions (2-4 nm). This work expands the synthetic methodology for polythioimides and offers new insights into the synthesis and functionalization of high-performance functional polymers.关键词：Polyimide;Polythioimide;Sulfur-oxygen exchange reaction;Precious metal adsorption15|1|0更新时间：2026-11-04
- 摘要：To address the intrinsic brittleness, poor thermal stability, and deterioration of recycling performance of the biobased plastic poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), an interfacial regulation strategy based on polymer-grafted nanoparticles was developed. Poly(glycidyl methacrylate) (PGMA) was covalently grafted onto the surface of silica (SiO2) nanoparticles via surface-initiated reversible addition-fragmentation chain transfer polymerization to obtain SiO2@PGMA nanoparticles, which were subsequently incorporated into a PHBV matrix to fabricate composite films. The results showed that the composite film containing 10% SiO2@PGMA exhibited the best overall performance. The tensile strength increased from 18.29 MPa to 36.94 MPa, while the toughness increased from 0.23 MJ·m-3 to 0.69 MJ·m-3. Meanwhile, the onset decomposition temperature (Tonset) increased from 261.4 ℃ to 275.6 ℃. After 20 recycling and reprocessing cycles, the composite film still retained 44.7% of its original tensile strength, significantly outperforming neat PHBV. Mechanistic studies revealed that the covalently grafted PGMA interfacial layer improved the compatibility between nanoparticles and the PHBV matrix, promoted heterogeneous nucleation, increased crystallinity, and refined the spherulitic structure of PHBV. In addition, the epoxy groups on the PGMA side chains could react with carboxyl groups generated during PHBV degradation, thereby suppressing the β-elimination reaction. The synergistic effects of interfacial compatibilization, heterogeneous nucleation, and thermal stabilization simultaneously enhanced the mechanical properties, thermal stability, and recycling performance of PHBV. This work provides a new interfacial design strategy for high-performance biodegradable plastics.关键词：Poly(3-hydroxybutyrate-co-3-hydroxyvalerate);polymer-grafted nanoparticles;Interfacial regulation;Thermal stability;Recycling performance169|37|0更新时间：2026-11-03
- 摘要：Polyolefin products are extensively utilized across numerous sectors of human life thanks to their low cost and tunable properties through molecular structure engineering. However, the existence of various additives and inorganic fillers, purposefully or unintentionally added into the polyolefins during synthesis and subsequent fabrication process, has been a challenge for all of high-temperature liquid chromatographic techniques. Removal of these impurities via bench-top high-temperature filtration prior to the actual chromatographic analyses significantly increases analytical complexity. Herein, an in situ analytical method integrating sample dissolution and impurity separation via a customized Filter Assembly is proposed. Only the initial sample preparation requires manual operation, whereas all subsequent experimental procedures may be automatically implemented, endowing the method with simplicity and high efficiency. Experimental results demonstrated that the proposed strategy can effectively eliminate impurity interference, and deliver accurate and well-reproducible data. Furthermore, this innovation is also suitable for quantifying the degree of cross-linking in cross-linked polyethylene samples with or without inorganic filler. The average testing time per sample is shortened to 54 min, in sharp contrast to the minimum 24 hour required by the standard ASTM D2765-16 method. Moreover, this developed approach provides a promising alternative for investigating the oxidation behavior of polyethylene and the characterization of other polymer systems containing insoluble components in the target solvent system.关键词：Polyolefin;Carbon black particle;Crosslinking;In situ filtration;Impurity;Fillers;Simultaneous dissolution and filtering45|1|0更新时间：2026-11-03
- 摘要：Oil-immersed capacitors are core equipment underpinning the stable operation of power systems, and silicone rubber (SiR) serves as a critical sealing material to ensure the reliable service of capacitors, which requires the simultaneous integration of excellent vegetable-based insulating oil resistance, insulation performance, and mechanical properties. In this study, 2-phenylacrylonitrile (α-PAN) with electron-scattering functionality was employed to crosslink and modify SiR. The effect of modifier addition ratio on the oil resistance of SiR in vegetable-based insulating oil was investigated. Further, the regulatory laws governing the influence of temperature conditions and modifier mass fraction on the crosslinking density and insulation performance of the composite dielectric were analyzed. Combined with molecular dynamics simulations, the mechanism by which α-PAN enhanced the performance of SiR was elucidated from the perspective of microstructure. Results indicated that the oil resistance of modified SiR in vegetable-based insulating oil was significantly improved; compared with pure SiR, the static contact angle of 0.7 wt% α-PAN/SiR increased by 4.66%. The AC breakdown strength first increased and then decreased with the increase of modification ratio, reaching a maximum value of 72.2 kV/mm at 0.5 wt%, and the breakdown performance of the composite dielectric decreased with the increase of temperature. Mechanical properties also improved with the increase of modification ratio, but slightly decreased after oil immersion. Theoretical calculations and trap characterization revealed that the introduction of α-PAN increased the distribution of deep traps inside the material, and the polar groups exerted the function of scattering electrons. Meanwhile, the increased crosslinking density reduced the free volume, thereby enhancing the electrical resistance performance of the material.关键词：Oil-immersed capacitor;Sealing material;Silicone rubber;Crosslinking modification;Insulating properties13|1|0更新时间：2026-11-03
- 摘要：The optical and catalytic properties of covalent organic frameworks (COFs) are highly dependent on electronic-structure synergy arising during framework assembly. However, the intrinsic properties of isolated monomers alone are often insufficient for accurately predicting the macroscopic performance of the resulting frameworks, which has become a central bottleneck in the rational design of COFs. In recent years, artificial intelligent (AI) has been widely introduced into COF performance prediction. Nevertheless, most existing models use molecular descriptors of monomers as inputs and therefore struggle to capture key assembly-induced effects such as orbital reorganization and charge transfer, resulting in limited predictive accuracy and chemical interpretability. To address this issue, this article systematically describes an AI prediction strategy based on dimer electronic-structure embedding. In this strategy, the dimer formed by connecting aldehyde and amine monomers through an imine linkage is used as an intermediate representation. By incorporating information on local bonding, frontier-orbital coupling, excited-state charge distribution, and related electronic features, this representation effectively bridges the cognitive gap between monomer structures and framework-level properties. This article first analyzes the physical origin of the prediction discrepancy between monomers and frameworks and clarifies the chemical rationale for using dimers as intermediate representations. It then summarizes AI model construction based on dimer descriptors, illustrates the application of this strategy using luminescent COFs and photocatalytic COFs as examples, and finally discusses current challenges and future perspectives.关键词：Covalent organic frameworks;Dimer;Electronic structure;Artificial intelligent;Macroscopic performance prediction13|0|0更新时间：2026-11-03
- 摘要：Current pesticide research and development emphasizes intelligent, precise, and environmentally friendly strategies aimed at enhancing pest control efficacy and reducing environmental pollution. In this study, cellulose nanocrystal-based microcapsules (IMI@pH-DMAEMA MC) were fabricated via in situ free-radical polymerization using Pickering emulsion templates for pesticide delivery. The microcapsules can serve as hydrophobic carriers, enabling sustained and stimuli-responsive pesticide release. The microcapsules achieved an encapsulation efficiency (EE) of 95.05% and a loading efficiency (LE) of 61.80% for IMI. They also exhibited UV-shielding properties that prevent the photodegradation of pesticide molecules and showed acid-responsive release under acidic conditions (pH=5). Rainfastness tests demonstrated that the wettability and retention of IMI@pH-DMAEMA MC on cotton, tomato, and cabbage leaf surfaces were superior to those of conventional commercial IMI emulsifiable concentrate (EC). Compared with EC (LC50: 32.035 mg/L) and IMI (LC50: 42.760 mg/L), IMI@pH-DMAEMA MC (LC50: 10.607 mg/L) exhibited significant advantages in efficacy evaluation against cotton aphids. Notably, preliminary ecotoxicity assessments showed that IMI@pH-DMAEMA MC has the potential to reduce acute toxicity and improve safety toward non-target organisms. Life cycle assessment (LCA) indicated that IMI@pH-DMAEMA MC had significantly lower environmental impacts than EC. Overall, this study developed an environmentally friendly, easy-to-prepare pesticide delivery system capable of sustained/controlled release, providing a promising strategy for smart pesticide delivery and contributing significantly to precision pesticide application and sustainable agricultural development.关键词：Pickering emulsion;In situ free radical polymerization;Cellulose nanocrystal;Microcapsule;Biosafety10|0|0更新时间：2026-11-03
- 摘要：The chain structure heterogeneity of polyolefin elastomer (POE) requires characterization in terms of both molecular weight and branching structure, yet the relationship between these two parameters proves challenging to establish using conventional one-dimensional characterization techniques. While cross-fractionation chromatography can provide the two-dimensional joint distribution of molecular weight and branching, the resulting chromatograms are typically interpreted only qualitatively, lacking established methodology for quantitative information conversion. This study focused on ethylene/1-octene and ethylene/1-butene copolymer elastomers. First, the overall differences in chain structure were characterized using mean parameters and one-dimensional dispersion parameters. Subsequently, an image-based feature extraction approach was applied to analyze the two-dimensional joint distribution, with the TGIC-GPC chromatography treated as a probability density image. Quantifiable image features were extracted across five dimensions: low-order moments, shape descriptors, topological characteristics, divergence, and quantiles. This approach converted a distribution that could previously only be observed qualitatively into a set of computable structural features. The study examined whether the method can extract coupled information inaccessible to one-dimensional characterization and evaluates its discrimination capability for different comonomer systems. The proposed method can quantitatively capture information such as the correlation between elution temperature and molecular weight, and can distinguish between the two comonomer families without relying on property-based data. The results indicate that image-based feature extraction provides an effective route for the quantitative description of the two-dimensional chain structure of POE.关键词：Polyolefin elastomer;Chain structure;Two-dimensional cross-fractionation;Image-based descriptors;Short-chain branching distribution8|1|0更新时间：2026-11-03
- 摘要：As one of the most widely accepted printing materials for fused deposition modeling (FDM) technique, poly(lactic acid) (PLA) offers numerous advantages, including renewability, biodegradability, excellent flowability, low printing temperature, and high dimensional accuracy. However, due to the layer-by-layer process intrinsic for FDM process, 3D-printed PLA parts tend to suffer from low crystallinity and poor interlayer bond quality, resulting in inferior and anisotropic mechanical properties compared to those of conventional injection-molded parts, which severely restricts their applications as load-bearing structural components and functional parts. This review, for the first time, focused on the adaptability of PLA materials to the FDM process from the material perspective, systematically analyzed their rheological behavior, crystallization characteristics, and molecular chain interdiffusion and entanglement of PLA during the key FDM sub-processes, including material extrusion, melt deposition, and interlayer bonding. In this regard, the excellent printability of PLA materials was thoroughly elucidated. Then, to address the interlayer bonding issue in PLA printing, this review presented a comprehensive overview of recent studies on bond interface enhancement, categorizing the main strategies into material modification, printing process optimization, external-field assistance and post-treatment, and discussing their effects on interfacial microstructure and mechanical properties. Finally, we presented an outlook on future developments for PLA printing, providing a reference for the design of PLA materials and their components with excellent performances and functionality.关键词：Fused deposition modeling;Poly(lactic acid);Printability;Interfacial bonding enhancement5|0|0更新时间：2026-11-03
- 摘要：Thermoplastic polyimide (TPI) insulated wires, which exhibit excellent insulating and radiation-resistant properties at extremely low temperatures, are designated as connection lines for the quench detection system of superconducting magnets. However, extensive cracking was unexpectedly observed after the implementation of vacuum pressure impregnation (VPI). The cracking behavior of TPI-insulated wires during the VPI process was systematically investigated. The results reveal that the failure is a multi-factor coupled phenomenon involving synergistic interactions between thermal, mechanical, and chemical mechanisms. First, the coiled configuration imposes sustained tensile stress on the outer arc of the insulation, while the extrusion process introduces molecular orientation and residual stresses into the TPI matrix. Although the VPI temperature (130 °C, 72 h) is well below the glass transition temperature (about 245 °C), sub-Tg segmental relaxation and amorphous structural rearrangement occurred, leading to free volume redistribution and residual stress relaxation. The constraint of the metallic conductor further restricts dimensional recovery, thereby promoting microcrack initiation. Second, low-molecular-weight species from the epoxy system, particularly the curing agent HY918 and the accelerator DY073-1, permeate into the amorphous regions of TPI, causing plasticization, swelling, and enhanced segmental mobility, which significantly reduces the local resistance to yielding and crack propagation. Under sustained bending stress, this results in a typical environmental stress cracking (ESC) acceleration effect. Third, the substantial mismatch in the coefficients of thermal expansion between the TPI and the metallic conductor generates considerable thermal stresses during the VPI thermal cycle, further exacerbating the cracking risk. Based on the mechanistic understanding, a protective strategy was implemented by wrapping the TPI wires with a thermal insulation layer prior to VPI. The protected specimens successfully passed the vacuum Paschen test, confirming that this approach effectively prevented resin permeation and thermally induced structural transitions in TPI insulation. This strategy provides a reference for the failures of quench diagnostic wires in similar superconducting magnets.关键词：Thermoplastic polyimide;Segmental relaxation;Environmental stress cracking;Electrical insulation8|6|0更新时间：2026-11-03
- 摘要：The commercialization of organic solar cells (OSCs) requires a transition from laboratory-scale spin-coating to high-throughput, environmentally friendly printing technologies. However, rapid crystallization and non-equilibrium molecular assembly during green-solvent processing often induce disordered morphologies and severe efficiency losses. Here, we introduce two nonhalogenated solid additives, 2-methoxynaphthalene (2-MN) and 2,7-dimethoxynaphthalene (2,7-MN), to regulate crystallization kinetics and film formation in blade-coated OSCs processed from the green solvent o-xylene. Benefiting from its symmetric molecular structure and stronger intermolecular interactions, 2,7-MN effectively prolongs the liquid-solid transition and suppresses premature aggregation, enabling the formation of a highly ordered bi-continuous interpenetrating network with optimized charge-transport pathways. As a result, green-solvent-processed OSCs achieve a champion power conversion efficiency of 20.19% with an exceptional fill factor of 81.52%. Notably, the morphology control enabled by 2,7-MN remains robust under high-speed coating (30 m·min–1), maintaining efficiencies approaching 19%. Importantly, large-area modules (15.84 and 76.95 cm2) deliver impressive efficiencies of 16.80% and 15.71%, respectively, which are the highest values reported in green-solvent-processed OSCs so far. This work establishes solid-additive engineering as an effective strategy for controlling non-equilibrium film formation toward scalable and sustainable organic photovoltaics.关键词：Organic solar cells;Environmentally friendly solvents;Solid additives;High-speed blade-coating;Large-area modules9|3|0更新时间：2026-11-03
- 摘要：Although the Fenton reaction has emerged as a promising tool for initiating reversible addition-fragmentation (RAFT) polymerization, traditional Fenton-RAFT systems are limited by their reliance on acidic media, radical-induced side reactions that restrict access to high-molecular-weight polymers, and poor catalyst cycling efficiency. To address these limitations, we employed a supramolecular Fenton catalyst based on host-guest complexation between cucurbit[7]uril (CB[7]) and a ferrocene derivative. This supramolecular Fenton catalyst accelerates hydroxyl radical generation, enabling the controlled synthesis of high-molecular-weight polymers at suitably low catalyst concentrations. Importantly, this system successfully bypassed the acidic media required in conventional Fenton reactions, successfully initiating RAFT polymerization at neutral or weakly basic pH. By establishing the correlation between host-guest chemistry, radical generation kinetics, and polymerization behavior, this work elucidates the mechanism of supramolecular Fenton-RAFT polymerization, offering a new strategy for the design of mild and efficient controlled radical polymerization systems.关键词：Reversible addition-fragmentation;Cucurbit[7]uril;Fenton catalysis;Ferrocene derivative;Host-guest complexation131|25|0更新时间：2026-11-02
- 摘要：Tread wear of aircraft tires is governed by harsh service conditions and material composition, which directly affect their service life. However, insufficient understanding of abrasion mechanisms under harsh service conditions imposes restrictions on the design and preparation of rubber materials with high abrasion resistance and low heat build-up. In this study, coumarone resin (CMR) and two types of tert-octyl phenolic resins, namely resole (PR45) and novolac (PR68), were introduced into natural rubber (NR) composites owing to their good compatibility with NR. To clarify the separate effects of large slip angle and high speed, the abrasion behavior of NR composites with different resins was evaluated under large-slip-angle abrasion (20° slip angle, 2.5 km/h) and high-speed abrasion (5° slip angle, 45 km/h) using a Laboratory Abrasion Tester 100 (LAT 100). The results showed that large-slip-angle abrasion was much more severe than high-speed abrasion, indicating that a large lateral force resulting from a large slip angle is much more detrimental to abrasion resistance than the surface temperature rise from high speed. Compared with CMR, both PR45 and PR68 improved the abrasion resistance of the NR composite under large-slip-angle conditions. The NR composite with PR68 also exhibited the lowest heat build-up among the three composites owing to its high cross-link density and uniform filler dispersion. Considering the abrasion resistance under a large slip angle and the overall performance, the PR68 composite exhibits great potential for extending the service life of aircraft tire treads.关键词：Resins;Abrasion resistance;Aircraft tires;Large slip angle;High speed13|14|0更新时间：2026-10-30
- 摘要：Compared with micelles and vesicles formed by the aggregation of conventional polymer chains, the aggregates of grafted nanoparticles demonstrate superior performance in structural stability, functional diversity, and application adaptability. These characteristics indicate their greater potential in fields such as drug delivery, biomaterials, and intelligent responsive systems. To further expand the range of achievable morphologies, this study introduces co-solvent effects into polymer-grafted nanoparticle systems assembled via polymerization-induced self-assembly (PISA). A nanoparticle model featuring dual symmetric initiation sites was developed, and dissipative particle dynamics (DPD) simulations were combined with a stochastic polymerization reaction to systematically investigate the influence of co-solvent interaction strength, nanoparticle filling ratio, and hydrophobic chain length on the self-assembly behavior of grafted nanoparticles. The results reveal that, by precisely tuning the simulation parameters, the controlled formation of various morphologies can be achieved, ranging from conventional spherical and lamellar structures to highly ordered helical aggregates which are preferentially formed when both solvents are strongly solvophobic toward the grafted chains, while a slight asymmetry exists between the two solvent–chain interaction strengths. These findings offer new theoretical insights and methodological support for the morphological control and functional design of polymer-based nanocomposites.关键词：Grafted nanoparticles;Co-solvent effect;Self-assembly;Dissipative particle dynamics12|5|0更新时间：2026-10-30
- 摘要：Piezoelectric elastic composites based on polydimethylsiloxane (PDMS) elastomer filled with polar phase poly(vinylidene fluoride) (PVDF) microspheres are fabricated. The regulatory role of the elastic polymer matrix structure on the performance of the composite, which is less concerned in previous studies, is explored. Here, we have elucidated that precise control of the PDMS crosslinked network governs the stress transfer mechanism, enabling rational design of high-performance piezoelectric composites. By tuning the crosslinker ratio, we achieve PDMS crosslinking densities ranging from 9.9×10–6 mol·cm–3 to 91.3×10–6 mol·cm–3, enhancing the output voltage of the piezoelectric composite with 10 wt% PVDF microsphere content from 5.3 V to 19.8 V. Finite element simulation attributes this enhancement to more efficient stress transfer within the elastomer matrix with higher crosslinking density, strengthening the dipole polarization response of polar PVDF microspheres. By increasing PVDF microsphere content to 30 wt%, the composite exhibits a piezoelectric coefficient (d33) of 74 pC·N–1 and a sensitivity of 647 mV·N–1, which are 37 and 20 times higher than unoptimized composites in this work, respectively. This work advances understanding of mechanoelectrical coupling in flexible piezocomposites and provides a platform for designing next-generation sensors for intelligent robotics and non-contact acoustic sensing.关键词：Crosslinking density engineering;Piezoelectric composite;Stress transfer mechanism;Flexible electronics13|14|0更新时间：2026-10-30
- 摘要：This work reports the synthesis of a new N,O-type nickel complex and its application in a Ni–AlEt3–BF3·MeOH catalytic system for homo- and co-oligomerization of 1-hexene and vinyl acetate. The system shows variable activity depending on the AlEt3 content and monomer ratio: 3.5 kg·(molNi·h)–1 for 1-hexene, 10.4 kg·(molNi·h)–1 for vinyl acetate, and up to 12.5 kg·(molNi·h)–1 in co-oligomerization (40 °C, toluene). Vinyl acetate is more reactive, and varying the monomer ratio allows control over the molecular weight and copolymer composition. Atmospheric pressure chemical ionization (APCI+/APCI–) mass spectrometry revealed chains with different initiating groups (H―, Et―, Bu―, and―CH2CH2―), indicating the involvement of Ni–alkyl, Ni–hydride, and Ni–ethylene species. 13C-NMR and quantum chemical calculations show predominant 1,2-insertion of alkenes, as well as mainly syndiotactic fragments, and isomerization of 1-hexene to 3-hexene at the nickel center. An ionic mechanism is proposed in which the balance of active Ni species and competitive monomer coordination governs the catalytic activity and product structure. Differential scanning calorimetry showed that the thermal behavior of the co-oligomers was strongly dependent on the AlEt3 content and comonomer ratio, underscoring their potential as tunable functionalized additives.关键词：Ni complexes;Co-oligomerization;Vinyl acetate;α-Olefins;Coordination polymerization17|5|0更新时间：2026-10-30
- 摘要：Poly(vinylidene fluoride) (PVDF)-based relaxor ferroelectric polymers incorporating groups with strong dipole moments can display multifunctional electrical responses and are highly promising for flexible electronics. Despite their evident advantages and years of research, achieving precise control over the dipole alignment and switching remains elusive, hindering further performance optimization. This study introduces a structural optimization strategy to modulate the multi-level structure of poly(vinylidene fluoride-co-trifluoroethylene-co-chlorofluoroethylene) (P(VDF-TrFE-CFE)) relaxor polymer. This approach enhances crystallinity, promotes chain orientation across both crystalline and amorphous regions, expands interplanar spacing and simultaneously introduces significant conformational disorder within nanosized polar domains. Such oriented nanofilms demonstrate stable relaxor characteristics with double the polarization intensity of unoriented films. Oriented relaxor polymers also uncover highly efficient cooperative polarization switching dynamics, which are both faster and more concentrated than those of their non-oriented counterparts. These findings provide key insights into relaxor behavior and establish a practical framework for the development of advanced low-field flexible electronics.关键词：P(VDF-TrFE-CFE);Relaxor polymer;Melt-drawn film;Orientation;Polarization switching9|3|0更新时间：2026-10-30
- 摘要：In “Polymer Chemistry” instruction, prevalent issues, including insufficient classroom teaching hours, overly abstract theories, and obscure knowledge points, tend to dampen students’ learning motivation and result in suboptimal academic performance. Aligned with the prevailing trend of digital education development, this study systematically explores the feasible integration pathways between polymer chemistry teaching and digital educational technologies and proposes a set of innovative teaching strategies and practical approaches. Through constructing disciplinary knowledge graphs, adopting animated demonstrations and virtual reality technologies, and developing dedicated online learning platforms, this study strives to establish an integrated, efficient, and personalized teaching framework. This framework can effectively boost students’ learning initiative and enhance learning efficiency. Meanwhile, it enables instructors to conduct real-time analysis of students’ learning data, thereby furnishing practical evidence for the iterative improvement of teaching modes. The proposed measures are conducive to facilitating the sustainable reform and innovative development of polymer chemistry teaching to better adapt to the educational demands in the digital age.关键词：“Polymer Chemistry” course;Digital teaching;Knowledge graph;Virtual reality;Online learning platform9|11|0更新时间：2026-10-29
- 摘要：To overcome the inherent performance limitations of conventional polyester materials and expand their potential application range, a series of bio-based siloxane-containing polyester elastomers (PPPBSS) were synthesized via melt polycondensation using hydroxyl-terminated polydimethylsiloxane (PDMS) as a flexible functional segment together with bio-based monomers. Subsequently, PPPBSS/SiO2 composites were fabricated to further investigate their mechanical performance. The effects of PDMS content on the structure and properties of PPPBSS elastomers were systematically studied. The chemical structures of the synthesized elastomers were confirmed using Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. The results indicate that increasing the PDMS content leads to a gradual decrease in the number-average molecular weight (Mn) of PPPBSS from 6.42×104 g/mol to 1.27×104 g/mol. Meanwhile, the glass transition temperature (Tg) decreases from –49 °C to –55 °C, demonstrating enhanced chain flexibility and improved low-temperature performance. The temperature at 5% weight loss (Td,5%) initially increases and then decreases with increasing PDMS content, reaching a maximum value of 354 °C for PPPBSS-3, indicating improved thermal stability. For the PPPBSS/SiO2 composites, both tensile strength and tensile modulus decrease as the PDMS content increases, with the tensile strength of PPPBSS-2/SiO2 decreasing to 4.6 MPa. Overall, the incorporation of PDMS effectively enhances the flexibility and thermal stability of the polyester elastomers while maintaining acceptable mechanical properties. These findings demonstrate the potential of bio-based siloxane-containing polyester elastomers for applications requiring excellent low-temperature flexibility and thermal resistance under demanding service conditions.关键词：Bio-based polyester elastomer;Polydimethylsiloxane;Low-temperature flexibility;Thermal stability15|10|0更新时间：2026-10-29
- 摘要：The rugged free-energy landscape of block copolymers features a multitude of local free-energy minima in addition to the only global free-energy minimum, giving rise to long-lived metastable states and enabling the fabrication of desired, metastable mesostructure in a process-accessible manner. Considering that the fabrication of perforated lamellar mesostructures in block copolymers via the stabilization strategy by either fine-tuning the chain architecture of the block copolymer or blending cannot fix the stacking sequence of hexagonally perforated layers in experiments due to similar free energies of different stacking sequences and leads to limited stable regions, using general symmetry considerations, we design a symmetry-conserving process to obtain the desired perforated lamellar mesostructure. The thermodynamically stable iHPa with P6/mmm symmetry of No. 191 space group in linear
$ {B}_{1}{A}_{1}{B}_{2}{A}_{2}{B}_{3} $ $ {\tilde{B}}_{1}{\tilde{C}}_{1}{A}_{1}{B}_{2}{A}_{2}{C}_{3} $ $ {C}_{1}{A}_{1}{B}_{2}{A}_{2}{C}_{3} $ $ {C}_{1}{A}_{1}{\tilde{C}}_{2}{\tilde{B}}_{2}{A}_{2}{C}_{3} $ 关键词：Block copolymer;Perforated lamellar mesostructure;P6/mmm symmetry;Process-directed self-assembly;Field theory10|3|0更新时间：2026-10-28 - 摘要：Biodegradable poly(L-lactide) (PLLA)/poly(ε-caprolactone) (PCL) blends exhibit poor toughness because of their incompatibility. In this study, double-graft polymers (DCL) with different molecular weights of poly(D-lactide) (PDLA) were successfully synthesized through grafting PDLA and PCL onto the multifunctional epoxy-based styrene-acrylic oligomer (ADR) molecular chain by reactive blending, and their structures were confirmed by FTIR and 1H-NMR spectra. Based on contact angle measurements and interfacial tension calculations, the graft copolymers preferentially localized at the interface between the two phases. This interfacial arrangement enhanced the interactions across the blend. The incorporation of PDLA was found to induce the formation of stereocomplex (SC) crystallites, which markedly reinforced the interfacial adhesion within the PLLA/PCL blend. Consequently, the elongation at break of the compatibilized blends exhibited an increasing trend with increasing compatibilizer content. Among them, the PLLA/PCL blend containing 5 wt% DCL with PDLA segments of 20 kg/mol exhibited the best tensile performance, outperforming the corresponding blend containing the double-graft copolymer with PLLA segments (LCL) owing to the formation of SC crystallites. Meanwhile, the influences of PDLA in DCL with varying Mn,designed on the morphology, crystallization, mechanical, thermal, and rheological properties of PLLA/PCL blends were investigated. It was found that DCL with a moderate length of PDLA (e.g., Mn,designed=20 kg/mol) displayed better compatibilization efficiency than copolymers with shorter or longer PDLA chains, significantly reducing the size of PCL domains and improving the dispersion uniformity. After incorporating DCL with the PDLA of Mn,designed=20 kg/mol, the elongation at break and fracture energy of the PLLA/PCL blends reached 304% and 9.7 kJ/m3, respectively, which were 20 and 24 times higher than those of the original PLLA/PCL. Compared to the uncompatibilized blend, the compatibilized blends displayed denser spherulites, which were derived from the nucleation of SC crystallization. The mechanical properties of the blends were improved through the transformation of the size and dispersion of PCL domains, and the size of spherulites tuned by PDLA with different molecular weights. By adjusting the molecular weight of PDLA in the compatibilizer, this study offers a strategy for fabricating PLLA-based materials with outstanding toughness.关键词：Poly(L-lactide);Double graft polymer;Stereocomplex crystallites;Toughness;Crystallization13|5|0更新时间：2026-10-28
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