Polymer Degradation and Stability最新文献

{"title":"Creation of sequence-regulating polyhydroxyalkanoate (PHA) synthases with improved thermostability using a full consensus design for the biosynthesis of 2-hydroxyalkanoate-based PHA block copolymers","authors":"Shoko Furukawa ,&nbsp;Naoya Nakagawa ,&nbsp;Shin-ichi Hachisuka ,&nbsp;Shogo Nakano ,&nbsp;Hiroya Tomita ,&nbsp;Hiroshi Kikukawa ,&nbsp;Ken'ichiro Matsumoto","doi":"10.1016/j.polymdegradstab.2025.111295","DOIUrl":"10.1016/j.polymdegradstab.2025.111295","url":null,"abstract":"<div><div>Engineered polyhydroxyalkanoate (PHA) synthase PhaC_AR is a chimeric enzyme composed of PhaCs from <em>Aeromonas caviae</em> and <em>Ralstonia eutropha</em> (formally <em>Cupriavidus necator</em>). The enzyme has a broad substrate scope and unique sequence-regulating capacity: spontaneous synthesis of various block copolymers. This study aimed to acquire new sequence-regulating PHA synthases with a broader substrate scope and improved thermal stability. To meet this goal, artificial PHA synthases were designed using the full consensus design (FCD) algorithm. Based on amino acid sequences of PHA synthases with homology to PhaC from <em>R. eutropha</em> in the database, four artificial PHA synthases, FcPhaC1, FcPhaC2, FcPhaC4, and FcPhaC5, were created and expressed in <em>Escherichia coli</em> together with the monomer-supplying enzyme. Cells were cultivated with the supplementation of monomer precursors in the medium. As a result, these four FcPhaCs synthesized poly(3-hydroxybutyrate) [P(3HB)], although polymer production was slightly lower than that obtained using PhaC_AR, indicating that the algorithm successfully designed functional enzymes. FcPhaC1, FcPhaC4, and FcPhaC5 remained active after isothermal treatment at 60 °C for 30 min, whereas PhaC_AR and FcPhaC2 were inactivated. Therefore, the artificial PhaCs possessed improved thermal stability compared to PhaC_AR. The four FcPhaCs synthesized poly(glycolate-<em>co</em>-3HB) [P(GL-<em>co</em>-3HB)] with a block sequence as well as PhaC_AR. FcPhaC4 exhibited the highest GL fraction in P(GL-<em>co</em>-3HB) among the PhaCs tested. FcPhaC4 synthesized P(3HB)-<em>b</em>-P(2-hydroxybutyrate) and P(3HB)-<em>b</em>-polylactate, indicating its broad substrate scope. These results demonstrated the effectiveness of the FCD approach for creating sequence-regulating PHA synthases applicable to a wide range of polymer syntheses.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"236 ","pages":"Article 111295"},"PeriodicalIF":6.3,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Realizing balanced thermal safety and heat insulation in hydrophobic silica aerogel composites","authors":"Miao Liu ,&nbsp;Yunli Huang ,&nbsp;Chang Xu ,&nbsp;Zhi Li ,&nbsp;Shengjie Yao ,&nbsp;Gaoxiang Long ,&nbsp;Qiong Liu ,&nbsp;Chuangang Fang ,&nbsp;Xiaoxu Wu","doi":"10.1016/j.polymdegradstab.2025.111294","DOIUrl":"10.1016/j.polymdegradstab.2025.111294","url":null,"abstract":"<div><div>Interest in high-performance multifunctional hydrophobic silica aerogels (HSAs) has generated extensive discussion around HSAs endowed with enhanced infrared radiation suppression and excellent flame retardancy. Herein, we propose an eco-friendly and low-cost strategy for fabricating fire safe and infrared radiative shielding HSAs for sustainable thermal insulation. The as-created FRSA-BN-0.2 aerogel composite demonstrated superior flame retardant properties, with reductions in peak of heat release rate, total heat release, and total smoke release of 18.8 %, 36.1 %, and 88.8 %, respectively, compared to those of pure HSA. Additionally, the initial thermal degradation temperature and the temperature of peak heat flow were markedly increased by 95.0 °C and 104.1 °C, respectively. Furthermore, the aerogel composite exhibited outstanding hydrophobicity (a water contact angle of 142.1°), excellent thermal insulation (a thermal conductivity of 23.2 mW/m·K), and substantial infrared shielding performance. In this study, commercial flame retardant 9,10-dihydro-9-oxa-10-phosphophenanthrene-10-oxide (DOPO) was used as an acid catalyst substitute for strong acids, and boron nitride nanosheets were incorporated into the matrix to develop advanced multifunctional HSA aerogel composites. This material shows significant potential for application in fields such as aerospace, building insulation, and industrial thermal insulation.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"236 ","pages":"Article 111294"},"PeriodicalIF":6.3,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical recycling of HDPE-based packaging: Interplay between cross contamination, aging and reprocessing","authors":"Chiara Gnoffo ,&nbsp;Rossella Arrigo ,&nbsp;Alberto Frache","doi":"10.1016/j.polymdegradstab.2025.111290","DOIUrl":"10.1016/j.polymdegradstab.2025.111290","url":null,"abstract":"<div><div>Achieving effective mechanical recycling strategies for polyolefins remains a major challenge for several reasons. Firstly, the thermo-mechanical degradation underwent during reprocessing, as well as the different degradation forms experienced during the service life, cause a severe modification of polyolefin microstructure, ultimately leading to a progressive deterioration of their performance. On the other hand, due to non-fully accurate sorting technologies, low levels of cross-contamination are commonly encountered in recycled polyolefins. All these features result in the obtainment recyclates with a heterogeneous and complex morphology, which significantly affects their final properties, often limiting their possible future applications. This work aims at addressing these issues, evaluating the combined effect of cross-contamination and of the degradation undergone by the polymers during service life and reprocessing for high-density polyethylene (HDPE) containing low amounts of polypropylene (PP) and polyethylene terephthalate (PET) as contaminants. In particular, pristine and cross-contaminated HDPE were subjected to photo-oxidative or thermo-oxidative treatments and the aged materials were reprocessed, aiming at simulating the real conditions of a typical mechanical recycling process. The obtained results demonstrated that cross-contamination minimises the functional degradation of HDPE, especially under photo-oxidative conditions. Conversely, the microstructural characterization pointed out that different microstructures can be achieved depending on the level of cross-contamination and on the aging treatment. Finally, it was shown that the presence of PP and PET as contaminants has a detrimental impact on the HDPE ductility, especially under thermo-oxidative conditions, while for photo-oxidised materials exerts a marginal role.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"236 ","pages":"Article 111290"},"PeriodicalIF":6.3,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Synthesis and characterization of eco-friendly chitosan-based waterborne polyurethanes and their ultraviolet degradation properties” [Polymer Degradation and Stability, 233 (2025) 111169]","authors":"Chun-Ta Wei ,&nbsp;Jhu-Lin You ,&nbsp;Kai-Yen Chin ,&nbsp;Shu Mei Chang ,&nbsp;Shun-Yi Jian ,&nbsp;An-Yu Cheng","doi":"10.1016/j.polymdegradstab.2025.111253","DOIUrl":"10.1016/j.polymdegradstab.2025.111253","url":null,"abstract":"","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"236 ","pages":"Article 111253"},"PeriodicalIF":6.3,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-efficiency synergetic clustered triazinylphosphinate composite flame retardant system enhance fire resistance, smoke suppression, and resilience of flexible polyurethane foams","authors":"Yi Zhang ,&nbsp;Wang Xi ,&nbsp;Lijun Qian ,&nbsp;Wei Tang ,&nbsp;Lijie Qu ,&nbsp;Jingyu Wang ,&nbsp;Yong Qiu ,&nbsp;Yajun Chen","doi":"10.1016/j.polymdegradstab.2025.111280","DOIUrl":"10.1016/j.polymdegradstab.2025.111280","url":null,"abstract":"<div><div>Flexible polyurethane foams (FPUF) with superior flame retardancy, smoke suppression, and high resilience remain a significant challenge, particularly in achieving a limiting oxygen index (LOI) above 26%. To address this, a novel clustered aluminum triazinylphosphinate (CATP) was synthesized, and a ternary flame-retardant system (CED), comprising CATP, expandable graphite (EG), and dimethyl methylphosphonate (DMMP), was developed. The effects of CED on the flame retardancy, smoke suppression, and mechanical properties of FPUFs were systematically investigated. In flame retardancy, 20%CED/FPUF achieved an LOI of 29.1% and attained a UL-94 HF-1 rating in horizontal combustion tests, a notable milestone for flame-retardant FPUFs. Compared to neat FPUF, the peak heat release rate, total heat release, and total smoke release of 20%CED/FPUF were reduced by 67.2%, 60.0%, and 50.5%, respectively, with a remarkable char yield of 60.1%. These results significantly outperformed those of FPUF with 20% formulation based on commercial aluminum diethylphosphinate (ADP) (20%AED/FPUF). This highlights the ability of the CATP/EG/DMMP system to impart exceptional flame suppression and efficient charring effects to FPUFs. Moreover, CATP enhanced the cross-linking density of the FPUF matrix, increasing the tear strength of CED/FPUF from 560 N/m to 810 N/m while maintaining excellent foam resilience. In summary, this study offers a promising strategy for developing FPUFs with high LOI values, outstanding flame retardancy and smoke suppression, and robust mechanical properties.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"236 ","pages":"Article 111280"},"PeriodicalIF":6.3,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143488803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced stabilisation performance of HDPE via siloxane bonded ZnO with phenolic antioxidants","authors":"Jianglai Ai ,&nbsp;Yuying Zheng ,&nbsp;Jie Zhang","doi":"10.1016/j.polymdegradstab.2025.111276","DOIUrl":"10.1016/j.polymdegradstab.2025.111276","url":null,"abstract":"<div><div>The poor resistance of high-density polyethylene (HDPE) to thermal-oxidative aging and ultraviolet (UV) degradation significantly limits its service life. In this study, the nanocomposite ZnO-AO was synthesized using γ-glycidoxypropyltrimethoxysilane (GPTMS) as a bridging agent, which facilitated the loading of a significant quantity of the hindered phenolic antioxidant (AO) onto the surface of ZnO nanoparticles, and the HDPE/ZnO-AO composites were subsequently prepared by melt blending. The results indicated that the combination of ZnO and AO was synergistic, and the more optimized para-substituent structure of AO significantly reduced the hydroxyl bond dissociation energy (BDE) of the hindered phenols, thereby enhancing antioxidant activity. Additionally, the hydroxyl groups on the surface of ZnO were substituted with AO, which improved the particle dispersion. After 400 h of UV aging, HDPE/ZnO-AO retained 78.36 % and 95.92 % of its elongation at break and impact strength, respectively, compared to only 2.25 % and 6.17 % for pure HDPE. After 28 days of thermal-oxidative aging, the carbonyl index of HDPE/ZnO-AO increased by only 0.18, significantly lower than that of HDPE (0.43). Accordingly, the ZnO and AO, covalently linked by GPTMS, demonstrated enhanced performance compared to individual original capabilities, successfully integrating efficient thermal-oxidative stability and UV protection. This study provides a promising approach for the development of long-lasting HDPE composites.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"236 ","pages":"Article 111276"},"PeriodicalIF":6.3,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143488804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Robust charring construction of thermoplastic polyurethane: Cyclotriphosphazene structure bearing alkynyl and its impacts on thermal degradation, burning behavior and toughness","authors":"Yiwen Hao ,&nbsp;Yunxian Yang ,&nbsp;Wen Chen ,&nbsp;Zhi Li ,&nbsp;Mengqi Yuan ,&nbsp;Guangyan Huang ,&nbsp;Dezhi Zheng","doi":"10.1016/j.polymdegradstab.2025.111279","DOIUrl":"10.1016/j.polymdegradstab.2025.111279","url":null,"abstract":"<div><div>As versatile engineering polymer, thermoplastic polyurethane (TPU) is up against the challenge of reducing fire hazard and maintaining excellent mechanics due to the intrinsic flammability and poor charring capability. Without relying on metal-containing hybrid, this study developed a single-component compound HCAP with pronounced charring capability with 71 % at 800 °C due to the self-reinforcement derived from the crosslinking reaction of alkynyl group, which also enabled TPU to possess excellent charring capability, flame retardancy, anti-dripping, and flexibility. The incorporation of HCAP decomposed to catalyze forming charring layer, meanwhile, alkynyl group started crosslinking reaction to further strengthen the layer, which enormously inhibited the decomposition of hard and soft segments at high temperature. Only adding 5 wt% HCAP increased the char residue of TPU from 2.9 % to 18.8 % at 800 °C, as well as 27.5 % LOI value and UL-94 V-0 rating accompanied by anti-dripping were also achieved. Along with some dilution effect in gas phase, noticeable reduction was observed for heat release and smoke release behavior. Moreover, the introduction of HCAP brought out plasticization for TPU, which resulted in increased elongation at break by 76.4 % and tensile toughness by 45 %. This improvement endowed TPU with expanded application in safety protection field.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"235 ","pages":"Article 111279"},"PeriodicalIF":6.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biosynthesis and property evaluation of poly(3-hydroxybutyrate-co-2-hydroxyalkanoate) containing 2-hydroxy-3-(4-hydroxyphenyl)propionate unit","authors":"Zihan Qie,&nbsp;Ramamoorthi M Sivashankari,&nbsp;Yuki Miyahara,&nbsp;Takeharu Tsuge","doi":"10.1016/j.polymdegradstab.2025.111277","DOIUrl":"10.1016/j.polymdegradstab.2025.111277","url":null,"abstract":"<div><div>Polyhydroxyalkanoate (PHA) biosynthesis has been performed using hydrophobic amino acids such as leucine, phenylalanine, and methionine as 2-hydroxyalkanoate (2HA) precursors, utilizing 2HA monomer-supplying enzymes (LdhA and HadA) derived from <em>Clostridioides difficile</em>. In this study, <span>l</span>-tyrosine was used as a 2HA precursor in the biosynthesis of poly(3-hydroxybutyrate-<em>co</em>-2HA) [P(3HB-<em>co</em>-2HA)] containing 2‑hydroxy-3-(4-hydroxyphenyl)propionate (2H3PhOHP), which shares the same carbon backbone as tyrosine and has hydroxy group in the side chain. The recombinant <em>Escherichia coli</em> DH5α, having the PHA biosynthesis pathway, was cultured by feeding glucose and <span>l</span>-tyrosine. The biosynthesized PHA was characterized by ¹H nuclear magnetic resonance (NMR), which revealed incorporation of the 2H3PhOHP unit into PHA up to 4.1 mol%. Modifying the phenol group of the 2H3PhOHP unit was performed using 2‑chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane, and phosphitylation was confirmed by ³¹P NMR analysis. Furthermore, the polymers' thermal and mechanical properties and wettability were investigated. Introducing 2H3PhOHP units into PHA led to a decrease in crystallinity and an increase in glass transition temperature and surface wettability. Thus, the 2H3PhOHP unit is a new type of building block for PHA that changes material properties and provides a hydroxyl group in the side chain as a chemical modification site to further improve the material properties of PHA.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"236 ","pages":"Article 111277"},"PeriodicalIF":6.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143488802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the hydrolysis behavior of poly(lactic acid) (PLA) and prediction of molecular weight distribution changes via the kinetic Monte Carlo method","authors":"Takanari Koike ,&nbsp;Yosuke Muranaka ,&nbsp;Yuta Okada ,&nbsp;Aira Onishi ,&nbsp;Taisuke Maki","doi":"10.1016/j.polymdegradstab.2025.111272","DOIUrl":"10.1016/j.polymdegradstab.2025.111272","url":null,"abstract":"<div><div>Poly(lactic acid) (PLA) is a biobased and biodegradable plastic derived from natural resources. In this study, the degradation mechanism of PLA during hydrolysis was experimentally verified, and a computational strategy was constructed to predict its degradation behavior. The reaction rates and solid-state structure of PLA during hydrolysis were measured, and the hydrolysis behavior of the crystalline and amorphous phases was investigated. The results indicated that the molecular chains were randomly cleaved in the amorphous phase but were cleaved only on the folding surface of the lamellar crystals in the crystalline phase. Furthermore, the degradation behavior of amorphous and semicrystalline PLA during hydrolysis was modeled and simulated using the kinetic Monte Carlo method. The specific degradation behavior of the crystalline phase was described by considering the distribution of lamellar crystals and the dependence of the degradation rate on the molecular chain position. With this model, the molecular weight distribution and weight loss of PLA can be predicted. This study is the first to construct a degradation model based on a solid-state structure that can predict not only the average molecular weight but also the molecular weight distribution.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"235 ","pages":"Article 111272"},"PeriodicalIF":6.3,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143445010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal stability and physical properties of poly(alkyl fumarate)s with Bornyl and Isobornyl groups as the geometrically isomeric esters","authors":"Eiji Ishiko,&nbsp;Yasuhito Suzuki,&nbsp;Akikazu Matsumoto","doi":"10.1016/j.polymdegradstab.2025.111273","DOIUrl":"10.1016/j.polymdegradstab.2025.111273","url":null,"abstract":"<div><div>Poly(dialkyl fumarate)s (PDRFs) with a poly(substituteda methylene) structure are highly transparent amorphous polymers with excellent heat resistance, mechanical, and optical properties. When optical polymer materials are used for electronic devices, both chemical and physical stability are required for the thermal properties of polymers. In this study, we conducted radical polymerization and copolymerization of dibornyl fumarate (DBoF) and diisobornyl fumarate (DIBF) with a symmetric ester structure as well as bornyl isopropyl fumarate (BoiPF) and isobornyl isopropyl fumarate (IBiPF) with an asymmetric structure to investigate the thermal and optical properties of the resulting PDRFs as the poly(substituted methylene)s including bicycloalkyl ester groups with a fixed molecular conformation in the side chain. It was revealed that the polymerization reactivity of the fumarates containing a bornyl group was higher than the fumarates including an isobornyl group. Monomer reactivity ratios were determined to be <em>r</em>₁ = 0.83 and <em>r</em>₂ = 0.92 for the copolymerization of DBoF (M₁) and diisopropyl fumarate (DiPF, M₂) while <em>r</em>₁ = 0.54 and <em>r</em>₂ = 1.60 for the system of DIBF (M₁) and DiPF (M₂). The thermal decomposition behavior of the resulting PDRFs depended on the geometric structure of the bornyl and isobornyl ester groups; for example, the onset temperatures of thermal decomposition were 306–320 °C and 240–269 °C for the Bo- and IB-containing PDRFs, respectively. The β-transition temperature also significantly increased from 64 °C for the diisopropyl ester of PDRF to 132 °C for the diborny ester. On the other hand, refractive index kept constant in a range of 1.46–1.48 for the Bo- and IB-containing PDRFs independent of the kind of a geometric structure and the contents. In order to clarify the thermal stability of the polymers, we investigated a mechanism for olefin elimination from the ester alkyl groups upon heating in the absence and presence of an acid, and discussed the effect of the geometrical structures, i.e., endo and exo configuration of the ester alkyl groups on the thermal decomposition mechanism. The aggregation structure of the polymer chains was also analyzed based on the results of wide-angle X-ray scattering (WAXS) analysis in the solid state to examine the relationship between the molecular packing and the physical properties of the PDRFs.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"235 ","pages":"Article 111273"},"PeriodicalIF":6.3,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143453765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}