Polymer Degradation and Stability最新文献_第5页

Novel formulations for the protection of wooden artifacts 保护木制文物的新配方

IF 7.4 2区化学

Polymer Degradation and Stability Pub Date : 2026-04-01 Epub Date: 2026-01-10 DOI: 10.1016/j.polymdegradstab.2026.111934

Laura Vespignani , Giulia Villano , Micol Bucci , Alessandra Cecchetti , Mara Camaiti , Antonella Salvini

{"title":"Novel formulations for the protection of wooden artifacts","authors":"Laura Vespignani , Giulia Villano , Micol Bucci , Alessandra Cecchetti , Mara Camaiti , Antonella Salvini","doi":"10.1016/j.polymdegradstab.2026.111934","DOIUrl":"10.1016/j.polymdegradstab.2026.111934","url":null,"abstract":"<div><div>Wooden artifacts are highly susceptible to degradation from moisture, pollutants, and ultraviolet (UV) radiation, which presents significant challenges in Cultural Heritage conservation. This study investigates the performances of novel formulations containing short-chain fluorinated oligoamides or fluorinated amines as protective treatments for wood artifacts and the effect of specific additives to increase their stability against photodegradation. Derivatives with C4 and C6 perfluorinated chains were obtained through ring-opening reactions and their formulations optimized for use with environmentally friendly solvents. When applied to beech wood, the coated surfaces significantly improved water and oil repellency, with Water Contact Angles (WCA) exceeding 125° and Oil Contact Angles (OCA) over 100°, while causing minimal visual changes to the surface. The addition of light stabilizers, particularly selected UV Absorbers (UVA), enhanced the durability of the coatings and slightly reduced photo-induced color changes observed in virgin wood and even when the coating alone was used. Accelerated aging tests and spectroscopic analysis confirmed the maintenance of protective properties over time by the formulations, supporting their potential as sustainable and reversible treatments for the long-term protection of wooden Cultural Heritage materials.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"246 ","pages":"Article 111934"},"PeriodicalIF":7.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145975011","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}

引用次数: 0

Thermo-aging induces adhesion between silicone foam and metal-mechanism behind 热老化引起泡沫硅酮与金属之间的黏附，其背后的机理

IF 7.4 2区化学

Polymer Degradation and Stability Pub Date : 2026-04-01 Epub Date: 2026-01-11 DOI: 10.1016/j.polymdegradstab.2026.111941

Yunpeng Xie , Zhaohui Xu , Lei Yu , Dayang Wang , Xiaolin Lu

{"title":"Thermo-aging induces adhesion between silicone foam and metal-mechanism behind","authors":"Yunpeng Xie , Zhaohui Xu , Lei Yu , Dayang Wang , Xiaolin Lu","doi":"10.1016/j.polymdegradstab.2026.111941","DOIUrl":"10.1016/j.polymdegradstab.2026.111941","url":null,"abstract":"<div><div>Silicone foam, as a damping material, is widely used between metal components in integrative device systems. After long-term service, silicone foam tends to adhere to metal substrates, thus leading to the disassembly difficulty and compromising the system reliability. Owing to the interfacial complexity when the silicone foam and the metal component stick to each other, the underlying adhesion mechanisms still remain unclear. This study aims to elucidate the adhesion mechanism between the silicone foam and the metal substrate using a stainless steel/silicone foam/stainless steel sandwiched structure through accelerated aging and under compressive stress. Multiscale techniques from morphology, spectroscopy and depth profile were applied to study the joint interfacial structures and elucidate the adhesion mechanism between the silicone foam and stainless steel. It was demonstrated that the silicone foam-stainless steel adhesion behavior arose from the synergistic effects of thermo-oxidative aging and compressive stress, which had induced physical and chemical changes of the silicone foam at the interface. Specifically, the interfacial interactions were comprised of covalent bonding (Si−O−Metal), micro-mechanical interlocking, hydrogen bonding, and van der Waals force. Such findings shall provide new insights into the adhesion mechanisms of polymer-metal interfaces and offer practical guidance for the design and reliability assessment of damping materials in engineering applications.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"246 ","pages":"Article 111941"},"PeriodicalIF":7.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145975013","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}

引用次数: 0

Tuning sequence length to regulate both toughness and biodegradation behavior of poly (butylene succinate-co-butylene adipate) 调整序列长度调节聚丁二酸-己二酸共丁二烯的韧性和生物降解行为

IF 7.4 2区化学

Polymer Degradation and Stability Pub Date : 2026-04-01 Epub Date: 2026-01-16 DOI: 10.1016/j.polymdegradstab.2026.111948

Haoran Sun , Shufeng Li , Junyu Li , Yuchuan Tian , Yi Liu , Liuchun Zheng

{"title":"Tuning sequence length to regulate both toughness and biodegradation behavior of poly (butylene succinate-co-butylene adipate)","authors":"Haoran Sun , Shufeng Li , Junyu Li , Yuchuan Tian , Yi Liu , Liuchun Zheng","doi":"10.1016/j.polymdegradstab.2026.111948","DOIUrl":"10.1016/j.polymdegradstab.2026.111948","url":null,"abstract":"<div><div>The extensive use of conventional plastics has resulted in severe environmental pollution, driving increasing interest in biodegradable polyesters that combine excellent performance with complete degradability. Poly (butylene succinate-<em>co</em>-butylene adipate) (PBSA), derived from poly (butylene succinate) (PBS) by incorporating flexible butylene adipate (BA) units, exhibits broad potential in composting, packaging, and agricultural films. In this study, a series of PBSA polyester materials with systematically varied BA unit sequence lengths were prepared by fine-tuning the composition of adipic acid (AA) and succinic acid (SA), aiming to investigate the effect of BA sequence length on the properties of PBSA. The results indicate that as the BA sequence length decreases, the crystal growth orientation of PBSA shifts from (020), (021), and other planes to (111), accompanied by increased interlamellar spacing and reduced crystallinity, these changes significantly accelerate the enzymatic degradation rate. Meanwhile, the shortened BA sequence promotes spherulite growth, which restricts the mobility of molecular chains and consequently leads to decreases in elongation at break and impact strength. Specific data show that after the shortening of the BA sequence, the elongation at break of PBSA decreases from 810% to 350%, the impact strength drops from 307.2 J/m to 211.9 J/m, and the degradation mass loss rate increases from 71.2% to 99.5%. This study confirms that regulating the BA sequence length enables the synergistic control of both mechanical properties and degradation performance of PBSA polyester materials.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"246 ","pages":"Article 111948"},"PeriodicalIF":7.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035629","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}

引用次数: 0

Improving flame retardancy, mechanical and water resistance properties of polypropylene using zinc oleate-modified intumescent flame retardant and coated red phosphorus 用油酸锌改性膨胀阻燃剂和包覆红磷改善聚丙烯的阻燃性能、力学性能和耐水性

IF 7.4 2区化学

Polymer Degradation and Stability Pub Date : 2026-04-01 Epub Date: 2026-01-15 DOI: 10.1016/j.polymdegradstab.2026.111947

Ziyi Zhang , Yangming Zou , Jun Sun , Hongfei Li , Qing Zhang , Xiaoyu Gu , Sheng Zhang

{"title":"Improving flame retardancy, mechanical and water resistance properties of polypropylene using zinc oleate-modified intumescent flame retardant and coated red phosphorus","authors":"Ziyi Zhang , Yangming Zou , Jun Sun , Hongfei Li , Qing Zhang , Xiaoyu Gu , Sheng Zhang","doi":"10.1016/j.polymdegradstab.2026.111947","DOIUrl":"10.1016/j.polymdegradstab.2026.111947","url":null,"abstract":"<div><div>To address the issue of excessive addition amount when using the expansive intumescent flame retardant (IFR, PAPP:MPP = 7:3) alone, a combination of high flame retardant efficiency and low toxicity coated red phosphorus ((w)RP) and IFR was added to polypropylene (PP) to improve the flame retardant performance of the PP composite. When the total addition amount of flame retardant decreases to 13 wt.%, it still could reach the UL-94 V-0 rating, with a limit oxygen index (LOI) value of 27.2%. Subsequently, in order to synergistically enhance its flame retardant performance, mechanical properties, and water resistance, the IFR needed to be modified. Zinc oleate (ZnOA) has good compatibility with PP and hydrophobicity, so it was selected to modify IFR to synthesis ZnOPM. Compared to PP/10%IFR/3%(w)RP, the PP/10%ZnOPM/3%(w)RP composite showed increased LOI to 28.8% while maintaining UL-94 V-0 rating, with peak heat release rate (pHRR) and total smoke production (TSP) reduced by 23.1% and 71.5% respectively. Additionally, compared with PP/10%IFR/3%(w)RP, the tensile strength and elongation at break of PP/10%ZnOPM/3%(w)RP increased by 25.1% and 98.1%. After water immersion tests, water absorption and flame retardant leaching rate of PP/10%ZnOPM/3%(w)RP decreased to 0.6% and 0.38%, with the composite maintaining excellent flame retardancy and mechanical properties. This study proposes a highly promising strategy for manufacturing PP composites with excellent flame retardant, smoke suppression, water resistance, and mechanical properties.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"246 ","pages":"Article 111947"},"PeriodicalIF":7.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035631","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}

引用次数: 0

Correlations among polylactic acid biodegradation, bacterial communities, and predicted functional genes under mesophilic and thermophilic composts 中温和亲热堆肥下聚乳酸生物降解、细菌群落和预测功能基因的相关性

IF 7.4 2区化学

Polymer Degradation and Stability Pub Date : 2026-04-01 Epub Date: 2026-01-05 DOI: 10.1016/j.polymdegradstab.2026.111921

Ian Cho, Kyung-Suk Cho

{"title":"Correlations among polylactic acid biodegradation, bacterial communities, and predicted functional genes under mesophilic and thermophilic composts","authors":"Ian Cho, Kyung-Suk Cho","doi":"10.1016/j.polymdegradstab.2026.111921","DOIUrl":"10.1016/j.polymdegradstab.2026.111921","url":null,"abstract":"<div><div>As a sustainable alternative to petroleum-based plastics, biodegradable plastics such as polylactic acid (PLA) have garnered increasing attention. However, despite being the most widely used biodegradable plastic, studies investigating the post-use degradation of PLA remain limited. This study compared the degradation behavior of PLA samples under mesophilic (35 °C) and thermophilic (58 °C) compost conditions and analyzed associated changes in microbial communities and predicted functional genes throughout the degradation process. The PLA film was completely degraded within 15 days under thermophilic conditions, whereas only a 13.7 % weight loss was observed after 40 days under mesophilic conditions. For PLA granules, weight loss after 65 days reached 24.8 % and 6.1 % under thermophilic and mesophilic conditions, respectively. SEM and FTIR analyses confirmed evidence of microbial degradation, such as surface erosion and ester bond cleavage. Spearman’s correlation analysis revealed that Bacillaceae-dominated microbial communities play an active role in PLA biodegradation in thermophilic environments, while <em>Georgenia</em> and <em>Cupriavidus</em> may function as potential PLA degraders in mesophilic environments. Functional gene prediction revealed that K01126 (glycerophosphodiester phosphodiesterase) and K01048 (lysophospholipase), both associated with PLA degradation, exhibited strong positive correlations with degradation rate, suggesting their key enzymatic roles in PLA hydrolysis. Furthermore, a promising PLA-degrading bacterium, <em>Ralstonia</em> sp. AF1, was isolated from compost following the degradation process. Overall, this study demonstrates the biodegradability of PLA under compost conditions through comprehensive analysis of degradation characteristics and bacterial community dynamics, and provides fundamental insights to enhance the degradation efficiency of PLA in compost environments.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"246 ","pages":"Article 111921"},"PeriodicalIF":7.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145941224","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}

引用次数: 0

Synthesis and degradation mechanisms of Schiff-base-containing phthalonitrile resins: Thermal stability and bond reconfiguration 含席夫碱邻苯二腈树脂的合成及降解机理：热稳定性和键重构型

IF 7.4 2区化学

Polymer Degradation and Stability Pub Date : 2026-04-01 Epub Date: 2026-01-15 DOI: 10.1016/j.polymdegradstab.2026.111945

Xiaolu Sun , Shilin Wang , Siyuan Dong , Xi Chen , Xinbo Dong , Yang Wang , Xigao Jian , Cheng Liu

{"title":"Synthesis and degradation mechanisms of Schiff-base-containing phthalonitrile resins: Thermal stability and bond reconfiguration","authors":"Xiaolu Sun , Shilin Wang , Siyuan Dong , Xi Chen , Xinbo Dong , Yang Wang , Xigao Jian , Cheng Liu","doi":"10.1016/j.polymdegradstab.2026.111945","DOIUrl":"10.1016/j.polymdegradstab.2026.111945","url":null,"abstract":"<div><div>With the rapid development of the aerospace field, higher requirements have been put forward for the heat resistance of thermosetting resins. In this study, an asymmetrical phthalonitrile monomer containing Schiff base moiety (SchB-PN) was synthesized by a two-step method with <em>N</em>-4′-hydroxybenzylidene-4-hydroxyaniline (N-hy) and 4-nitro-<em>o</em>-phthalonitrile. The structure and properties of SchB-PN were characterized by ¹H NMR, <sup>13</sup>C NMR, <sup>1</sup>H–<sup>1</sup>H gCOSY, HRMS, FTIR, XRD, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and rheology. SchB-PN had a relatively low viscosity of 0.179 Pa·s when molten, and due to the presence of imine and cyano groups, SchB-PN resin exhibited self-curing characteristics. Furthermore, SchB-PN resins were cured with different curing agents and curing processes. It was found that SchB-PN-APn-400 resin cured by SchB-PN and <em>p</em>-aminobenzonitrile (APn) at 400 °C demonstrated excellent thermal stability and thermal oxidative stability, with the temperature of 5 % weight loss (<em>T</em><sub>5 %</sub>) of 530 °C in nitrogen and 534 °C in air, and the residual carbon rate was 74.9 % at 800 °C in nitrogen atmosphere. The curing mechanism of SchB-PN-APn resin and the cooperative curing mechanism of imine bonds and cyano groups were studied and clarified through FTIR, in-situ infrared technology, SEM and EDS. In addition, the thermal stability and pyrolysis mechanism of SchB-PN were systematically investigated by TGA and TG-FTIR techniques, as well as the compensatory effect of the Schiff base bond breaking and reconnection during the degradation process. The relevant data and analysis results highlight the potential application prospects of SchB-PN-APn resin in aerospace and high-performance engineering fields.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"246 ","pages":"Article 111945"},"PeriodicalIF":7.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035627","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}

引用次数: 0

Biomimetic soil-root-mineral system toward VER composites with enhanced mechanical property, good recyclability and excellent flame retardancy 仿生土壤-根-矿物体系研究VER复合材料力学性能增强、可回收性好、阻燃性优异

IF 7.4 2区化学

Polymer Degradation and Stability Pub Date : 2026-04-01 Epub Date: 2026-01-15 DOI: 10.1016/j.polymdegradstab.2026.111943

Ying-Ming Li , Hang-Ping Fang , Shuang-Lin Hu , Yao Deng , De-Yi Wang

{"title":"Biomimetic soil-root-mineral system toward VER composites with enhanced mechanical property, good recyclability and excellent flame retardancy","authors":"Ying-Ming Li , Hang-Ping Fang , Shuang-Lin Hu , Yao Deng , De-Yi Wang","doi":"10.1016/j.polymdegradstab.2026.111943","DOIUrl":"10.1016/j.polymdegradstab.2026.111943","url":null,"abstract":"<div><div>The inherent flammability, poor mechanical property and non-recyclability of vinyl resins (VER) has hindered their widely use in aerospace and construction applications. In this work, inspired by the soil-root-mineral synergy in natural ecosystems, a novel P-N flame retardant (AT) was covalently immobilized within the polymer matrix, mimicking root anchoring in soil. Concurrently, functionalized glass fibers (FGF) were incorporated, analogous to mineral particles, to synergistically enhance the flame retardancy and mechanical reinforcement for VER. When incorporating 14 wt% AT and 1 wt% FGF, the composite achieved a UL-94 V-0 rating with a limiting oxygen index (LOI) of 31.3%. Cone calorimetry test (CCT) revealed that the VERAT/FGF<sub>1</sub> composite exhibited significant reductions in heat release rate (HRR), total heat release (THR), and smoke production rate (SPR) of 54.4%, 39.3%, and 20.1%, respectively, compared to pure VER. Comprehensive analyses demonstrated that the flame-retardant mechanism involved synergistic effects in both condensed and gas phases. Simultaneously, the VERAT/FGF<sub>1</sub> composite demonstrated 41.9% and 10.7% enhancements in tensile strength and impact resistance, respectively, compared to neat VER. Chemical degradation of VERAT/FGF<sub>1</sub> by solvent method for efficient recycling of glass fibers, providing a new strategy for reuse of vinyl polyester composites.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"246 ","pages":"Article 111943"},"PeriodicalIF":7.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035624","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}

引用次数: 0

Phosphate ester-based polyols as flame retardants for flexible polyurethane foam: fire behavior and mechanism 磷酸酯基多元醇作为柔性聚氨酯泡沫的阻燃剂：燃烧性能和机理

IF 7.4 2区化学

Polymer Degradation and Stability Pub Date : 2026-04-01 Epub Date: 2026-01-09 DOI: 10.1016/j.polymdegradstab.2026.111932

Zhuo-Lin Li , Wen Ye , Xiang Ao , Ping-Yang Li , Xiong Xiao , Xiao-Lei Li , Zhao-Cong Shang , De-Yi Wang

{"title":"Phosphate ester-based polyols as flame retardants for flexible polyurethane foam: fire behavior and mechanism","authors":"Zhuo-Lin Li , Wen Ye , Xiang Ao , Ping-Yang Li , Xiong Xiao , Xiao-Lei Li , Zhao-Cong Shang , De-Yi Wang","doi":"10.1016/j.polymdegradstab.2026.111932","DOIUrl":"10.1016/j.polymdegradstab.2026.111932","url":null,"abstract":"<div><div>To address the high flammability, rapid flame spread, and non-self-extinguishing behavior of flexible polyurethane foams (FPUFs), a series of novel liquid reactive phosphate ester polyols, denoted as BOPF, CPF, and EPF, were synthesized by reacting propylene oxide with structurally distinct phosphorus compounds. When incorporated into FPUFs at 3 wt%, CPF demonstrated exceptional performance, achieving an LOI of 20.5% and a 16.4% reduction in peak heat release rate, which decreased to 740 kW/m². A key innovation was that FPUF-3CPF achieved rapid self-extinguishing within 5 s in the vertical burning test, while simultaneously exhibiting an 8.9% increase in tensile strength, effectively overcoming the common drawback of mechanical property deterioration associated with traditional flame retardants. Further investigation into the volatiles released during thermal degradation and the residues after cone calorimetry tests provided insight into the possible flame-retardant mechanisms. In the gaseous phase, the decomposition of phosphorus-based flame retardants generated phosphorus-containing free radicals, which inhibited the combustion chain reaction. In the condensed phase, these flame retardants promoted the formation of a dense and stable char layer on the foam surface. This work provided a feasible strategy for designing high-performance, halogen-free FPUFs that combine rapid self-extinction, enhanced mechanical properties, and significantly reduced fire hazard.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"246 ","pages":"Article 111932"},"PeriodicalIF":7.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035630","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}

引用次数: 0

In-situ monitoring temporal evolution of functional groups for decoupling multi-stage depolymerization kinetics of polyurethane foam 聚氨酯泡沫解聚多阶段解聚动力学中官能团的实时监测

IF 7.4 2区化学

Polymer Degradation and Stability Pub Date : 2026-04-01 Epub Date: 2026-01-25 DOI: 10.1016/j.polymdegradstab.2026.111959

Xi Liu, Mengman Weng, Yongkui Ren, Fengliang Ji, Haowei Jiang, Zhao-Xia Huang, Jin-ping Qu

{"title":"In-situ monitoring temporal evolution of functional groups for decoupling multi-stage depolymerization kinetics of polyurethane foam","authors":"Xi Liu, Mengman Weng, Yongkui Ren, Fengliang Ji, Haowei Jiang, Zhao-Xia Huang, Jin-ping Qu","doi":"10.1016/j.polymdegradstab.2026.111959","DOIUrl":"10.1016/j.polymdegradstab.2026.111959","url":null,"abstract":"<div><div>It is challenging to precisely control the depolymerization of chemically cross-linked polymers in heterogeneous solid-liquid systems, which requires more effort to illustrate the depolymerization kinetics, especially by utilizing in-situ characterization techniques to monitor the temporal evolution of chemical structures in heterogeneous solid-liquid systems. In this work, we employ the in-situ attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy to monitor the temporal evolution of functional groups during the depolymerization of waste polyurethane foams. A kinetic model based on two Boltzmann sigmoidal functions was developed to decouple the multi-stage depolymerization behavior. This model resolves the process into four mechanistic stages: induction and interfacial activation, rapid primary depolymerization and limited swelling, synergistic swelling and progressive depolymerization, and final network collapse leading to complete decrosslinking. It further identifies the time-dependent evolution of an inert aromatic C-H out-of-plane bending vibration, enabling the identification of characteristic transition times and a criterion for complete depolymerization. Temperature, catalyst loading, and solvent content significantly influence the kinetic parameters, with solvent content showing an apparent non-monotonic effect. Peak deconvolution of the carbonyl region further reveals distinct degradation behaviors for ester, urethane, and urea linkages. Overall, this study establishes an in-situ spectroscopic framework for elucidating multi-stage depolymerization kinetics in cross-linked polymer networks and provides mechanistic insight into polyurethane degradation processes.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"246 ","pages":"Article 111959"},"PeriodicalIF":7.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146184965","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}

引用次数: 0

Enhancing flame retardancy, smoke suppression, and hydrothermal aging resistance of polypropylene composites via metal-oxide loaded acid-modified kaolin as a synergist 金属氧化物负载酸改性高岭土作为增效剂增强聚丙烯复合材料的阻燃、抑烟和水热老化性能

IF 7.4 2区化学

Polymer Degradation and Stability Pub Date : 2026-04-01 Epub Date: 2026-01-05 DOI: 10.1016/j.polymdegradstab.2026.111923

Mengyuan Zheng , Jingjing Yang , Gehao Guo , Yifang Hua , Si Guo , Lingyao Zeng , Yuhang Wang , Xiaoyu Gu , Wufei Tang , Sheng Zhang

{"title":"Enhancing flame retardancy, smoke suppression, and hydrothermal aging resistance of polypropylene composites via metal-oxide loaded acid-modified kaolin as a synergist","authors":"Mengyuan Zheng , Jingjing Yang , Gehao Guo , Yifang Hua , Si Guo , Lingyao Zeng , Yuhang Wang , Xiaoyu Gu , Wufei Tang , Sheng Zhang","doi":"10.1016/j.polymdegradstab.2026.111923","DOIUrl":"10.1016/j.polymdegradstab.2026.111923","url":null,"abstract":"<div><div>A co-precipitation route is employed to load Mg<sup>2+</sup>, Cu<sup>2+</sup>, and Zn<sup>2+</sup> onto acid-treated kaolin (AK), and then calcined at 450°C to obtain the corresponding metal oxides (MO) within the AK (MOAK). These MOAK are then used as synergists for the intumescent flame retardant (IFR) composed of PAPP (polyphosphoric acid piperazine salt)/MPP (melamine polyphosphate) at a mass ratio of 7:3, in the preparation of polypropylene (PP) composites. Partial replacement of IFR with 2 wt.% MOAK, exemplified by PP/14%IFR/2%ZnAK, markedly enhances flame retardancy. This composite achieves UL-94 V-0, while simultaneously reduces the peak heat release rate (pHRR) from 171 kW/m<sup>2</sup> to 95 kW/m<sup>2</sup>, and the total smoke production (TSP) from 1.36 m<sup>2</sup> to 0.91 m<sup>2</sup>. These values correspond to reductions of 44% and 33%, respectively, relative to PP/16%IFR composite. Furthermore, the three MOAK synergists demonstrate unique properties: the MgAK-containing composite achieves the most significant smoke suppression, reducing TSP by 97%; the CuAK-modified system meets flame-retardant requirements but compromises mechanical properties; whereas the ZnAK-containing composite achieves an optimal balance between flame retardancy and mechanical performance, alongside remarkable hydrothermal aging resistance. After immersion in 70°C water for 7 days, the PP/14%IFR/2%ZnAK retains 99.9% of its original limiting oxygen index (LOI) and 96.0% impact strength. Collectively, these findings indicate that co-precipitation and calcination of MO on AK enables efficient IFR systems, endowing PP with durable flame-retardant performance.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"246 ","pages":"Article 111923"},"PeriodicalIF":7.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145974642","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}

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