Polymer Degradation and Stability最新文献

{"title":"Self-degradable poly(lactic acid) for accelerated soil biodegradation via enzyme activity-preserving encapsulation","authors":"Soyeong Lee ,&nbsp;Min Jang ,&nbsp;Yujin Choi ,&nbsp;Mingyeong Jang ,&nbsp;Nayoung Kim ,&nbsp;Yong Sik Ok ,&nbsp;Sung Yeon Hwang","doi":"10.1016/j.polymdegradstab.2026.111987","DOIUrl":"10.1016/j.polymdegradstab.2026.111987","url":null,"abstract":"<div><div>Although poly(lactic acid) (PLA) degrades under industrial composting conditions, its degradation under milder environments is limited. Embedding enzymes, such as proteinase K (PK), into polymer matrices can enhance degradation, yet challenges such as enzyme deactivation during high-temperature extrusion and high enzyme costs hinder practical applications. To overcome these limitations, we develop a hydrophilic, enzyme-compatible matrix with a low melting point and low crystallinity to stably embed enzymes in PLA. This matrix, based on poly(propylene succinate) and calcium carboxymethyl cellulose, enables uniform enzyme dispersion, resulting in a ∼1.8-times increase in catalytic activity, thermal stability up to 150 °C, and the preservation of enzymatic activity for up to 17 days. Enzyme-embedded PLA films containing this matrix exhibit sufficient mechanical properties for packaging applications. Furthermore, the biodegradation rate of these films reaches 40%, which is ∼2.6-times higher than that of PLA under composting conditions. The degradation products show no adverse effects on soil health. This enzyme-mediated degradation system represents a scalable platform with broad applicability for sustainable polymer development.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"247 ","pages":"Article 111987"},"PeriodicalIF":7.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171921","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":"Microstructural evolution and thermal protection mechanism of ceramifiable silicone composites via boron phosphate phase transformation","authors":"Jingyao Xu ,&nbsp;Wanting Song ,&nbsp;Sujie Hu ,&nbsp;Laibin Zhang ,&nbsp;Shuilai Qiu","doi":"10.1016/j.polymdegradstab.2026.111999","DOIUrl":"10.1016/j.polymdegradstab.2026.111999","url":null,"abstract":"<div><div>The pervasive risk of thermal runaway propagation in lithium–ion battery energy storage stations necessitates advanced thermal barrier materials. To address this, we developed a biomimetic silicone matrix composite inspired by volcanic rock strata. This material integrates a zinc borate/black phosphorus flame–retardant system, a silica aerogel insulation network, and an aramid fiber reinforcement. Upon high–temperature exposure, the composite spontaneously forms a dense, coherent boron phosphate (BPO₄) ceramic layer, akin to volcanic rock, which provides exceptional thermal shielding. Experimental results demonstrate outstanding performance: the composite maintains mechanical stability from –40 to 300 °C, reduces surface temperature rise by 75% compared to pure silicone foam, and lowers the peak heat release rate and total smoke production by 52.5% and 47.9%, respectively. In simulated thermal runaway tests, it completely prevented propagation to adjacent cells and reduced mass loss by 66.1%. Mechanistic studies reveal that the performance stems from a synergistic gas–phase and condensed–phase flame–retardant action, coupled with enhanced insulation and interfacial reinforcement. This work presents a promising material solution for enhancing the intrinsic safety of Energy storage power stations.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"247 ","pages":"Article 111999"},"PeriodicalIF":7.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171482","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":"New insights into the photodegradation of aromatic polyurea: A spectro-thermo-mechanical characterization study","authors":"Shiho Kuwashiro ,&nbsp;Amritesh Kumar ,&nbsp;George Youssef","doi":"10.1016/j.polymdegradstab.2026.111982","DOIUrl":"10.1016/j.polymdegradstab.2026.111982","url":null,"abstract":"<div><div>Polyurea emerged as a strategic material for protective coatings in harsh environments, with widespread adoption in civilian infrastructure and defense-related applications. However, polyurea, including an aromatic backbone that provides structural robustness, is susceptible to environmental stressors during extended deployment, most notably UV radiation. The objective of this research is to provide new insights into the mechanical, thermal, and physicochemical performance of polyurea after extended exposure to ultraviolet irradiation. Polyurea samples exhibited surface cracking and an increase in reduced modulus upon UV exposure, as probed using nanoindentation. The increase in reduced modulus also extends in depth, and the depth at which the elastic modulus increases is proportional to the exposure duration. FT-IR analysis indicated that multiple chemical structures were altered by UV exposure. Most prominent is the cleavage of ester bonds connecting soft and hard segments, as well as the cleavage of aliphatic chains. In addition, in UV-exposed polyurea, hydroperoxide decomposition led to crosslinking via radical recombination, and new hydrogen-bonding structures formed within the hard segments. These phenomena contribute to the increased surface reduced modulus. UV exposure of polyurea also decreased its thermal decomposition temperature, as determined by thermogravimetry and calorimetry. These outcomes challenge previous experimental results and provide novel mechanistic insights that accelerate the development of next-generation protective materials and structures with prolonged deployment durations.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"247 ","pages":"Article 111982"},"PeriodicalIF":7.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171915","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":"Shape-stabilized and flame retardant polyethylene glycol composites based on dual cross-linked network for thermal energy storage","authors":"Shushu Xu ,&nbsp;Shenghua Yang ,&nbsp;Xiaming Feng ,&nbsp;Hongyu Yang ,&nbsp;Chaojun Wan ,&nbsp;Cheng Yan","doi":"10.1016/j.polymdegradstab.2026.111988","DOIUrl":"10.1016/j.polymdegradstab.2026.111988","url":null,"abstract":"<div><div>Polyethylene glycol (PEG), recognized as an environmentally benign phase change energy storage material, offers advantages including high latent heat capacity, stable performance, and biodegradability. However, its inherent flammability, low thermal conductivity, and propensity for molten leakage significantly constrain practical implementation. To address these limitations, expandable graphite (EG) was employed as flame retardant and thermal conductor, while 2-hydroxyethyl methacrylate phosphate (HMP) served as cross-linking agent with flame retardant effect. Upon simple thermally curing, both chemical and physical cross-linking reactions ensued, forming a three-dimensional network structure that substantially improved the dimensional stability of PEG. By varying mass ratios of raw materials, the optimal formulation was determined to comprise 12 wt% EG and 10 wt% HMP. This composite achieved a UL-94 V-0 rating with LOI value of 28.5% in term of flame retardancy, exhibited a melting enthalpy of 132 J/g, and effectively attained shape stabilization. Moreover, thermal stability assessments revealed a significant increase in the decomposition temperature compared to pure PEG, accompanied by enhanced char formation that contributed to the flame retardant efficacy. The gas-phase flame retardant mechanism, involving radical quenching and dilution effects, was confirmed through evolved gas analysis, further supporting the composites’ robustness for energy storage applications.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"247 ","pages":"Article 111988"},"PeriodicalIF":7.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171919","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":"Integrating disulfide linkages and stretching processes in thermoplastic starch/polylactide blends: A model study on retarding retrogradation","authors":"Piyawanee Jariyasakoolroj ,&nbsp;Suttinun Phongtamrug ,&nbsp;Patakorn Pilasen ,&nbsp;Wanwisa Limphirat ,&nbsp;Suwabun Chirachanchai","doi":"10.1016/j.polymdegradstab.2026.111962","DOIUrl":"10.1016/j.polymdegradstab.2026.111962","url":null,"abstract":"<div><div>Thermoplastic starch (TPS) is a promising biodegradable material; however, its practical application is limited by retrogradation, which deteriorates its mechanical and barrier performance. This work presents a model, solvent-free strategy to suppress TPS retrogradation and improve its compatibility with polylactide (PLA) by combining thiol-enabled chemical modification with biaxial orientation (BO). Starch is chemically modified using mercapto acid derivatives and plasticized with glycerol via twin-screw reactive extrusion to produce crosslinkable Mx-TPS, which is subsequently melt-blended with PLA to form precursor sheets and BO films. Processing-induced disulfide formation and partial plasticizer immobilization stabilize TPS, while BO stretching promotes strain-induced crystallization and lamellar alignment in the PLA phase, collectively reducing V_H-type starch crystallization during storage at 6 °C and 50 °C. X-ray diffraction confirms suppressed V_H-type crystallinity, and the resulting films show improved moisture resistance and gas barrier performance. Mercaptosuccinic acid (MS) provides the strongest overall effect, consistent with enhanced interfacial interactions. Compared with BO-PLA/TPS, BO-PLA/MS-TPS films exhibited reduced oxygen permeability from 1153.72 to 589.31 cc·mil/m²·day·atm and water vapor permeability from 159.21 to 68.90 <em>g</em>·mil/m²·day·atm, together with improved tensile performance. This study demonstrates a practical processing concept to enhance the long-term stability and barrier functionality of PLA/TPS-based films for biodegradable packaging applications.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"247 ","pages":"Article 111962"},"PeriodicalIF":7.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171989","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":"Polymerization catalyst is key: Predicting molecular changes during mechanical recycling of phillips and ziegler-natta catalyst high-density polyethylene (HDPE)","authors":"Alexsandar Arumugam ,&nbsp;Jana Zimmermann ,&nbsp;Thea Weingartz ,&nbsp;Michael Fischlschweiger ,&nbsp;Valerian Hirschberg","doi":"10.1016/j.polymdegradstab.2026.111981","DOIUrl":"10.1016/j.polymdegradstab.2026.111981","url":null,"abstract":"<div><div>We present a systematic approach to predict the molecular degradation of high-density polyethylene (HDPE) during mechanical recycling based on the polymerization catalyst. HDPE represents about 12.5 wt % of the polymer world production and is industrially mainly produced by Phillips (P-HDPE) and Ziegler-Natta catalyst (ZN-HDPE). Two blow-moulding P- and ZN<img>HDPE with identical melt flow indices (MFI) were subjected to mechanical recycling at an extrusion temperature of 170 °C and 210 °C, a screw speed of 180 rpm, and recycling times from 10 to 240 min. Chemical and rheological characterization revealed, that despite similar initial melt properties, P-HDPE and ZN- HDPE exhibited fully contrary degradation mechanisms: for recycled P- HDPE at 170 °C and 210 °C, the complex viscosity (|η*|) and the molecular weight drastically increased after 10 min of recycling time due to star-like branching, followed by chain scission at 170 °C, but crosslinking at 210 °C, resulting in unprocessable, rubber-like material. In contrast, recycled ZN<img>HDPE exhibited a continuous drop in molecular weight and in |η*| across all conditions. This work provides a polymerization catalyst-specific framework to predict and engineer thermo-mechanical molecular degradation pathways in HDPE recyclates, paving the way to tailored recycling strategies to obtain value-added materials.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"247 ","pages":"Article 111981"},"PeriodicalIF":7.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171914","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":"Non-migrating multifunctional macromolecular antioxidants based on hyperbranched polyglycerol for thermooxidative and photooxidative stabilization of polyolefins","authors":"Katarína Mosnáčková ,&nbsp;Bence Sármezey ,&nbsp;Anna Vykydalová ,&nbsp;Dóra Fecske ,&nbsp;Györgyi Szarka ,&nbsp;Béla Iván ,&nbsp;Jaroslav Mosnáček ,&nbsp;György Kasza","doi":"10.1016/j.polymdegradstab.2026.111974","DOIUrl":"10.1016/j.polymdegradstab.2026.111974","url":null,"abstract":"<div><div>Multifunctional macromolecular antioxidants represent environmentally advantageous alternatives to conventional low molecular mass stabilizers for improving the long-term stability of polyolefins, such as polyethylene (PE) and polypropylene (PP), while minimizing additive migration in the surrounding environment. Hyperbranched macromolecules are especially promising for such purposes, due to their high number of functionalities, ease of production and limited migration. In this study, two hyperbranched polyglycerol (HbPG)-based antioxidants (HbPG-AoxAc) with different molar masses were synthesized by covalent attachment of sterically hindered phenolic units via esterification of the hydroxyl groups of HbPG. These macromolecular stabilizers were characterized by GPC, ¹H NMR and UV–Vis spectroscopies, confirming high antioxidant functionality and well-defined composition. Their performance in thermooxidative and photooxidative stabilization of LDPE and PP was systematically explored and compared with conventional low molecular mass stabilizers using chemiluminescence, oxidative induction time (OIT) determined by DSC, UV–Vis and FTIR spectroscopies. The obtained results indicate that the synthesized HbPG-AoxAc macromolecular antioxidants provide significant stabilization against both thermooxidative and photo-induced degradation in the polyolefin matrices, particularly in PP, and exhibit comparable efficiency to Irganox® 1010 and Irganox® HP-136, while outperforming the secondary antioxidant Irgafos® 168. Importantly, hexane extraction tests revealed negligible leaching of the macromolecular antioxidants, in sharp contrast to the extensive migration and loss observed for the low molecular mass reference additives. These findings confirm the potential of the HbPG-based macromolecular antioxidants as effective, low-migration additives for advanced and environmentally friendly polyolefin applications.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"247 ","pages":"Article 111974"},"PeriodicalIF":7.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171910","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":"A phosphorus/nitrogen-containing additive to simultaneously improve the flame retardant and anti-corrosion of epoxy resins","authors":"Yifang Hua ,&nbsp;Xiaobei Li ,&nbsp;Salman Khalid ,&nbsp;Jun Sun ,&nbsp;Shuhui Liu ,&nbsp;Lianfeng Wu ,&nbsp;Jiang Jing ,&nbsp;Xiaoyu Gu ,&nbsp;Sheng Zhang","doi":"10.1016/j.polymdegradstab.2026.111973","DOIUrl":"10.1016/j.polymdegradstab.2026.111973","url":null,"abstract":"<div><div>Epoxy resins (EP) suffer from high flammability and poor corrosion resistance, which restrict their application in harsh environments. Herein, a novel phosphorus- and nitrogen-containing additive (MMPADA) was synthesized through the reaction of 3,5-diamino-1,2,4-triazole (DATA) with dimethyl methylphosphonate (DMMP). Remarkably, with only 2 wt.% MMPADA incorporation, the EP coating kept high transparency and exhibited outstanding flame retardancy. The latter was evidenced by a limiting oxygen index of 31.9 % and a UL-94 V-0 rating, and significant reductions in heat and smoke release. Meanwhile, electrochemical impedance spectroscopy (EIS) confirmed that the EP/2%MMPADA coating maintained much higher charge transfer resistance than the control EP, even after 40 days of immersion in 3.5 wt.% NaCl solution, demonstrating superior long-term anticorrosion performance. These results highlighted that incorporating merely 2 wt.% MMPADA endowed EP coatings with excellent transparency, flame retardancy, and corrosion resistance, thereby offering a feasible strategy to extend their service life in demanding environments.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"247 ","pages":"Article 111973"},"PeriodicalIF":7.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171913","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":"Inhomogeneous photodegradation of BPA polycarbonate due to light diffraction by pigment particles","authors":"James E. Pickett ,&nbsp;Gudrun A. Hutchins ,&nbsp;Jacob P. Pickett","doi":"10.1016/j.polymdegradstab.2026.111986","DOIUrl":"10.1016/j.polymdegradstab.2026.111986","url":null,"abstract":"<div><div>Bisphenol-A polycarbonate (PC) containing pigment particles exhibits distinctive photodegradation patterns after accelerated weathering exposure using a xenon arc lamp. The patterns are caused by diffraction of ultraviolet (UV) light and can be visualized by transmission electron microscopy (TEM) of thin cross sections after staining with RuO₄. Paraboloid shapes much larger than the particles are visible in sections made perpendicular to the surface while circular bullseye patterns are seen in slices parallel to the surface. Diffraction patterns can occur because the UV source is relatively compact and the orientation of the source and specimen surface is fixed. No patterns are visible by TEM in samples after outdoor exposure where the UV is more dispersed and the sun/specimen orientation varies with hour and season. Therefore, the patterns are artifacts of the test method. Comparison of published yellowing, physical property change, and erosion rates for pigmented and unpigmented PC after outdoor and xenon arc exposure suggests diffraction has at most a minor effect on the PC photodegradation rate.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"247 ","pages":"Article 111986"},"PeriodicalIF":7.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171917","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":"Molecular oxidative/pyrolysis evolution and influence on short-beam shear damage performance of 3D braided composites","authors":"Yuanyuan Wu ,&nbsp;Shuwei Huang ,&nbsp;Rui Wang ,&nbsp;Zhongwei Li ,&nbsp;Baohui Shi","doi":"10.1016/j.polymdegradstab.2026.111994","DOIUrl":"10.1016/j.polymdegradstab.2026.111994","url":null,"abstract":"<div><div>The damage caused by loading along the thickness direction of 3D braided composite is a common failure factor in the service process of their aerospace structural components, especially considering the environmental effect such as oxidative at high temperature. This paper has innovatively counted and analyzed the thermo-oxidative degradation path and productions of the oxidative skin layer and the pyrolysis core layer in 3D carbon fiber/epoxy resin braided composite using reactive molecular dynamic (RMD) method. The resulting influences on the stress and damage evolution in the braided composite were discussed during short-beam shear loading. The results indicate that the freedom volume ratio gradually stabilize for the oxidative skin layer and continuously decline for the pyrolysis core layer, and the values of the former are lower. After aging for 16 days at 180°C, the main oxidative productions include C13-O, C2, C3, C1, H, H₂O, CO₂ and H_2, and the sequence of formation rate is H₂O &gt; CO₂ &gt; H₂. Whereas, the main pyrolytic productions include C14-O, C7, C3, C2, C1, H₂O, CO₂ and H₂, and the sequence of formation rate is H₂O = CO₂ &gt; H₂. The above variations at the molecular scale in the braided composite have reduced the 7.66 ± 0.84% for peak stress and 8.84 ± 0.52% for interlaminar shear strength values. Furthermore, the differences between the oxidative skin layer and the pyrolytic core layer also change the initial damage at the bottom tension end in the composite during loading caused by the more brittle of the oxidative skin layer.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"247 ","pages":"Article 111994"},"PeriodicalIF":7.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171479","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}