{"title":"Degradation of polypropylene random copolymer in aqueous solution of chlorine dioxide: Effect of crystalline structure and morphology","authors":"Rohollah Shamizade, Gholamreza Pircheraghi","doi":"10.1016/j.polymdegradstab.2025.111540","DOIUrl":"10.1016/j.polymdegradstab.2025.111540","url":null,"abstract":"<div><div>The influence of crystal polymorphism (α, β, γ phases) and spherulite diameter (D<sub>s</sub>) on the degradation of polypropylene random copolymer (PP-R) in chlorine dioxide (ClO<sub>2</sub>) was investigated. Three PP-R samples—one neat (P) and two with α (A) or β (B) nucleating agents, resulting in initial spherulite diameters of <em>P</em> > <em>B</em> > <em>A</em>—were aged in 20 ppm ClO<sub>2</sub> solution at 60 °C. Chemical degradation, monitored by Carbonyl Index (FTIR) and elongation at break (tensile tests), was most pronounced in sample A (smallest spherulites) and least in sample P (largest spherulites). After 1440 h, sample A exhibited the highest carbonyl content, and its elongation at break reached 50 % of its initial value earlier than sample B, while sample P showed minimal degradation. Rheological and DSC analyses further characterized the degradation. The findings conclude that spherulite size, rather than crystalline phase, predominantly controls PP-R's chemical stability in ClO<sub>2</sub>, with smaller spherulites rendering the material more susceptible to degradation.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"241 ","pages":"Article 111540"},"PeriodicalIF":6.3,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144654083","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}
Ngan T Nguyen , Lam H. Pham , Hai T Vo , DongQuy Hoang , Cuong N Hoang
{"title":"Novel reactive flame-retardant coating prepared from waste polyethylene terephthalate, phenylphosphonic acid, and novolac glycidyl ether","authors":"Ngan T Nguyen , Lam H. Pham , Hai T Vo , DongQuy Hoang , Cuong N Hoang","doi":"10.1016/j.polymdegradstab.2025.111544","DOIUrl":"10.1016/j.polymdegradstab.2025.111544","url":null,"abstract":"<div><div>As global production and consumption of poly(ethylene terephthalate) (PET) becomes higher, so does the amount of waste PET. Several methods of waste PET reduction like mechanical and chemical recycling have been investigated. In this report, we selected the new chemical recycling of PET by transesterification reaction with adipic acid to regain terephthalic acid and oligo(ethylene-adipate-co-terephthalate) (OEAT). Terephthalic acid can also be recovered from PET by hydrolysis in the presence of acid or base catalysts at high temperature and pressure, then sophisticated equipment is required. The advantage of the transesterification over hydrolysis process is performing at atmospheric pressure. OEAT contains both aliphatic and aromatic units and reactive carboxylic acid end groups contributing to the flexibility and thermal stability of the prepared polymer. By <sup>1</sup>H NMR characterization, the molar percentages of adipate and terephthalate units in OEAT were 59.4 % and 40.6 %, respectively. The reactions of OEAT and phenyl phosphonic acid with novolac glycidyl ether have been carefully investigated separately or as mixture. The combination of OEAT and phenyl phosphonic acid enhanced the flame retardancy of the obtained coating. Structures of the prepared polymers were confirmed by FTIR and their thermal properties were investigated by DSC-TGA. A simple dicarboxylic acid (adipic acid) was used in place of OEAT for comparison. The cured coating showed higher gel content, higher flexural ultimate stress, strain at break and modulus. However, the flame test of this sample failed. Consequently, both aromatic terephthalate units of OEAT and phosphonate group of PPA contribute to the flame retardancy of the coating.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"241 ","pages":"Article 111544"},"PeriodicalIF":6.3,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144654084","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}
Johanna Morales , Rose Mary Michell , Denis Rodrigue
{"title":"Impact of mechanical reprocessing on degradation and performance of PA 11 and PA 11–LDPE blends","authors":"Johanna Morales , Rose Mary Michell , Denis Rodrigue","doi":"10.1016/j.polymdegradstab.2025.111541","DOIUrl":"10.1016/j.polymdegradstab.2025.111541","url":null,"abstract":"<div><div>This study examines the mechanical recycling of a virgin PA 11 and a post-consumer PA 11–low density polyethylene (LDPE) (90/10) blend over ten reprocessing cycles. Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (¹H NMR) analyses revealed changes in the intensity and position of specific absorption bands and proton signals, indicating progressive chain scission and molecular rearrangements. A carbonyl band was identified in the virgin PA 11 after reprocessing, a confirmation of thermo-oxidative degradation. Mechanical testing showed gradual reductions in elastic modulus, stress at break, and impact strength, with significant deterioration from the third cycle onward. Rheological analysis revealed consistent decreases in storage modulus (<em>G′</em>), loss modulus (<em>G″</em>), complex viscosity (<em>η*</em>), and changes in damping factor (tan <em>δ</em>), reflecting lower molecular weight and altered viscoelastic behavior. This was further confirmed via Cole–Cole and van Gurp–Palmen plots. In the post-consumer blend, scanning electron microscopy (SEM) showed progressive coalescence of LDPE droplets, contributing to reduced interfacial area and decreased impact resistance. In general, the results showed that virgin PA 11 retains acceptable performance up to three cycles, while the post-consumer blend exhibits faster and more pronounced degradation driven by both chemical and morphological changes particularly due to droplet coalescence and loss of interfacial area.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"241 ","pages":"Article 111541"},"PeriodicalIF":6.3,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144633943","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}
Ya Xue , Ying Li , Fei Zhong , Zhongxiang Bai , Pan Wang , Kui Li , Fan Lei , Zhoukun He , Yang Yang , Wei Feng , Xulin Yang
{"title":"Bio-based benzoxazine containing phthalonitrile: Nonsolvent synthesis, curing behavior and pyrolysis mechanism","authors":"Ya Xue , Ying Li , Fei Zhong , Zhongxiang Bai , Pan Wang , Kui Li , Fan Lei , Zhoukun He , Yang Yang , Wei Feng , Xulin Yang","doi":"10.1016/j.polymdegradstab.2025.111542","DOIUrl":"10.1016/j.polymdegradstab.2025.111542","url":null,"abstract":"<div><div>Traditional benzoxazines are largely constrained by the dependence on non-renewable resources, solvent-based synthesis, and insufficient thermal resistance. This study presents a novel high-performance bio-based benzoxazine containing phthalonitrile (BZPN), synthesized via melt condensation using eugenol, 3-aminophenoxyphthalonitrile, and paraformaldehyde. The chemical formula of BZPN was validated by FTIR, ¹H and ¹³C NMR analyses. The curing of BZPN involves ring-opening polymerization of oxazine group and ring-forming polymerization from phthalonitrile unit, yielding polybenzoxazines and heteroaromatics respectively. Combined TG-DTG, TG-FTIR with TG-MS technique, the three-stage thermal pyrolysis mechanism of BZPN was proposed. The initial decomposition (<em>T<sub>dm1</sub></em>=395 °C) occurs through the cleavage of C<img>N, C<img>O, and C<img>C bonds in the polybenzoxazine, releasing NH₃, H₂O, CH₄, and CO₂. The second stage (<em>T<sub>dm2</sub></em>=485 °C) involves the cleavage of C<img>O and C<img>C bonds in the heteroaromatic networks by releasing NH₃, H₂O, CH₄, and CO₂. The final carbonization stage (<em>T<sub>dm3</sub></em>=615 °C) includes the transformation of highly aromatic compounds into graphite. With the facile solvent-less synthesis method and superior comprehensive properties (compressive strength: >220 MPa, <em>T<sub>g</sub></em>: >375 °C, <em>T<sub>d5</sub></em>: >390 °C, and <em>C<sub>y</sub></em>: 72 % at 800 °C), bio-based BZPN is a promising high-performance thermosetting resin for advanced industrial and engineering applications.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"241 ","pages":"Article 111542"},"PeriodicalIF":6.3,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144614721","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}
Renjian Xie , Xiu-e Li , Xiaohong Liu , Jialin Li , Shanshan Zhou , Yumei Li , Hui Yang , Guoming Yuan , Kun Wu , Kunxin Wang
{"title":"Inspired by the shell of an armadillo-black phosphorus nanosheets weared Ar plasma protective clothing to enhance the fire safety of epoxy resin","authors":"Renjian Xie , Xiu-e Li , Xiaohong Liu , Jialin Li , Shanshan Zhou , Yumei Li , Hui Yang , Guoming Yuan , Kun Wu , Kunxin Wang","doi":"10.1016/j.polymdegradstab.2025.111533","DOIUrl":"10.1016/j.polymdegradstab.2025.111533","url":null,"abstract":"<div><div>Black phosphorous (BP) nanosheets as a novel two-dimensional material have revealed dramatically fire safety promotion in polymer nanocomposite. Herein, plasma cleaning machine (PC), equiped with Ar plasma, was applied to protect BP (PCBP) to enhance the environmental stability of BP. Further, the fire safety of epoxy resin (EP) was enhanced. The molecular dynamics simulation (MDS) results indicate that the values of binding energy between Ar plasma and BP at 0 K, 200 K, 400 K, 600 K, and 800 K were -847.0148, -847.3044, -847.3012, -847.2975, and -847.3035 eV, respectively. It meant that there was a strong electrostatic interaction between BP and Ar plasma, and it was not affected by temperature. Electron Paramagnetic Resonance (EPR) test revealed that the free radical strength of PCBP decreased than BP, suggesting that the environmental stability of PCBP was better than that of BP. The results of cone calorimetry test (CCT) displayed that the flame retardant ability of EP was enormously improved through the addition amount of 1.5 wt % PCBP nanosheets, for instance, the peak heat release rate (pHRR) and the total heat release (THR) were descended by 22.98 % and 16.24 %, respectively. Epoxy nanocomposite with 1.5 wt% PCBP nanosheets can achieve UL-94 V-0 rating level with a limit oxygen index (LOI) of 30.4. Thermogravimetric analysis (TGA) result displayed that the residual weight rate increased by 23.27 %. Raman test of the residual char layer proved that the value of I<sub>D</sub>/I<sub>G</sub> declined from 4.021 to 3.098, indicating a promotion in the degree of graphitization. These were attributable to the cooperation effect of physical barrier, free radicals trapping and catalytic conversion into char of PCBP.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"241 ","pages":"Article 111533"},"PeriodicalIF":6.3,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144633945","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}
Jiuke Chen , Sandro Lehner , Sin Yong Teng , Sabyasachi Gaan , Daniele Passerone , Manfred Heuberger , Ali Gooneie
{"title":"Thermal decomposition mechanisms of phosphorus flame retardants: A combined theoretical and experimental approach","authors":"Jiuke Chen , Sandro Lehner , Sin Yong Teng , Sabyasachi Gaan , Daniele Passerone , Manfred Heuberger , Ali Gooneie","doi":"10.1016/j.polymdegradstab.2025.111543","DOIUrl":"10.1016/j.polymdegradstab.2025.111543","url":null,"abstract":"<div><div>Phosphorus flame retardants (PFRs) are one of the main candidates for a fully organic, sustainable replacement to traditional halogenated FRs. However, their unexpected decomposition remains an open challenge hindering their full potential for sustainable applications in polymers. To address this issue, thermal decomposition of two common PFRs, namely 6H-Dibenz[c,e][1,2]oxaphosphorin, 6-[(1-oxido-2,6,7-trioxa-1-phospha bicyclo[2.2.2]oct‑4-yl)methoxy]-, 6-oxide (DOPO-PEPA) and Aflammit PCO 900 (AF), was studied using density functional theory (DFT) coupled with experimental methods, particularly the direct inlet probe-mass spectrometry (DIP-MS). The DIP-MS spectra were processed and analyzed using algorithms to identify potential decomposition products of DOPO-PEPA and AF. Under inert atmospheric conditions, bond dissociation and proton attack were identified as the predominant decomposition pathways. Geometries of intermediates, transition states, and products along potential energy surfaces were identified through DFT calculations. For DOPO-PEPA, the dissociation of the C<img>O bond linking the DOPO and PEPA moieties was identified as the most kinetically favored dissociation pathway; while for AF, bond dissociation was found energetically demanding. On the other hand, protonation processes demonstrate more dependence on the availability of protons. Cross-validating computational results with experimental observations verified the pathways through which DOPO-PEPA and AF release phosphorus-containing species and other decomposition products. Benefitting from a combination of fundamental molecular models and experimental evidence, this study provides new insights into the molecular mechanisms of thermal degradation of PFRs, thus providing a template for developing new FRs with enhanced thermal stability.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"241 ","pages":"Article 111543"},"PeriodicalIF":6.3,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144654087","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}
Thomas Viel , Immacolata Liotta , Roberto Avolio , Maria Emanuela Errico , Loredana Manfra , Giovanni Libralato , Valerio Zupo , Maria Costantini , Mariacristina Cocca
{"title":"The fate of biodegradable polyesters in the marine environment","authors":"Thomas Viel , Immacolata Liotta , Roberto Avolio , Maria Emanuela Errico , Loredana Manfra , Giovanni Libralato , Valerio Zupo , Maria Costantini , Mariacristina Cocca","doi":"10.1016/j.polymdegradstab.2025.111539","DOIUrl":"10.1016/j.polymdegradstab.2025.111539","url":null,"abstract":"<div><div>The fate of polymeric materials depends on the chemical structure of the polymer and on environmental conditions. To mitigate environmental issues associated with plastic mismanagement at the end of life, great attention has been addressed to compostable and biodegradable polymers. Some of these polymers, even if biodegradable, are found in the form of microplastics in the environment. In this work, the degradation behavior of five biodegradable polymers, poly(butylene succinate), PBS, poly(butylene succinate-<em>co</em>-butylene adipate), PBSA, poly(ε-caprolactone), PCL, polyhydroxy butyrate, PHB, and poly (lactic acid), PLA, was evaluated using <em>ad hoc</em> set mesocosms simulating their presence in marine environment at different water depths for 363 days. Higher mass loss during aging was recorded for PCL and PHB. Cracks, grooves and holes were detected on all the samples at the end of the test. Exposure into seawater induces hydrolytic degradation of the polyesters confirmed by Fourier transform infrared and NMR spectroscopies. The identification of the polymer phase in the sand suggests the occurrence of fragmentation phenomena of some samples, particularly PCL, during ageing. Remarkably, not all biodegradable polyesters are biodegraded in the sea, thus their mismanagement at the end of life is likely to induce progressive accumulation in the environment.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"241 ","pages":"Article 111539"},"PeriodicalIF":6.3,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144663304","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}
Amy Honnig Bassett , Alexander B. Morgan , Giuseppe R. Palmese
{"title":"Investigating the effects of furan ring substitution and network position on char formation in intrinsically flame-retardant epoxy resins","authors":"Amy Honnig Bassett , Alexander B. Morgan , Giuseppe R. Palmese","doi":"10.1016/j.polymdegradstab.2025.111538","DOIUrl":"10.1016/j.polymdegradstab.2025.111538","url":null,"abstract":"<div><div>Flame-retardant chemicals are often added to epoxy resins to decrease their flammability. However, there is an increasing interest in transitioning from these chemicals to intrinsically flame-retardant epoxies. One promising approach involves incorporating furan into polymers, which is known to enhance char formation. Nonetheless, the chemical reactions that allow furan to convert from five-membered rings to six-membered rings in the final carbon structure remain poorly understood. In this work, three furan-based epoxy resins were developed to explore how furan ring substitution and network positioning affect char formation: furan diepoxy (FDE), methyl furan diepoxy (MethylFDE), and tetraglycidyl amine of difuran diamine (TGDFDA). Thermogravimetric analysis (TGA) and evolved gas analysis showed that the network position of the furan ring has a greater impact on char formation than ring substitution. PolyTGDFDA, which has main-chain furan rings, had the highest char yield of 44.0 ± 0.6 % at 1000 °C in a nitrogen atmosphere. In contrast, PolyFDE, containing pendant, monosubstituted furan rings, displayed a char yield of 38.6 ± 0.7 %, while PolyMethyl-FDE, with pendant, disubstituted furan rings, yielded 22.4 ± 2.1 %. The influence of furan ring substitution and network position significantly impacted the char yield, but not the type of carbon formed, as shown by Raman spectroscopy. The enhanced char yields positively affected the flammability performance, as evaluated by micro-combustion calorimetry (MCC). These furan-based epoxies showed a path toward developing intrinsically flame-retardant polymers without needing flame-retardant chemicals. Furthermore, insights into the role of furan rings during char formation were developed.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"241 ","pages":"Article 111538"},"PeriodicalIF":6.3,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144633946","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}
Jing Qiao , Guanyue Zeng , Lingfeng Cui , Hua Wang , Hanhua Tan , Fuping Dong , Yuzhu Xiong
{"title":"Preparation of core-shell hybrid particles based on biomass resveratrol and phosphazene molecules co-assisted bimetallic ZIF achieves efficient flame-retardant modification and mechanical property enhancement of polyurea","authors":"Jing Qiao , Guanyue Zeng , Lingfeng Cui , Hua Wang , Hanhua Tan , Fuping Dong , Yuzhu Xiong","doi":"10.1016/j.polymdegradstab.2025.111536","DOIUrl":"10.1016/j.polymdegradstab.2025.111536","url":null,"abstract":"<div><div>The evolution of Spray Polyurea Elastomer (SPUA) technology has revolutionized protective coating materials. While market demands have accelerated polyurea (PUA) development, achieving high-performance fire-resistant formulations remains a critical challenge. In this study, a novel core-shell hybrid flame-retardant particle, FPM@ZIF-67/ZIF-8, was successfully synthesized through the precise assembly of bimetallic ZIF onto functional polyphosphazene microspheres (FPM). By strategically incorporating biomass-derived resveratrol and phosphazene molecules to introduce flame-retardant features, such as phosphorus-nitrogen heterocycles and aromatic rings, and capitalizing on the synergistic interaction between these structures and the smoke-suppressing properties of ZIFs, highly efficient flame-retardant PUA composites were successfully prepared. Specifically, the 5 wt % FPM@ZIF-67/ZIF-8 composite achieves UL-94 V-0 rating with limiting oxygen index (LOI) increasing from 20.3 % to 28.4 %. Relative to pure PUA, reductions of 41.6 %, 40.9 %, and 37.8 % were observed in pHRR, THR, and TSP, respectively. Furthermore, robust interfacial adhesion between FPM@ZIF-67/ZIF-8 particles and the PUA matrix, combined with efficient energy dissipation mechanisms, resulted in enhanced tensile strength (20.8 MPa) and elongation at break (1014.6 %). This study advances the design of bio-derived core-shell flame-retardant hybrids, facilitating the creation of high-performance PUA elastomers with balanced fire resistance and mechanical integrity. These findings hold substantial implications for broadening PUA applications in fire-sensitive domains.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"241 ","pages":"Article 111536"},"PeriodicalIF":6.3,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144604280","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}
Zhenlin Jiang , Jizhe Liu , Wanyu Xie , Yi Song , Ning Liu , Jiaguo Li , Baoxiu Wang , Jiapeng Chen , Shiqiang Song , Peng Ji
{"title":"Degradation-reconstruction-functional enhancement coupled upcycling of waste PET into recycled thermoplastic polyurethane with P-N synergistic flame retardancy","authors":"Zhenlin Jiang , Jizhe Liu , Wanyu Xie , Yi Song , Ning Liu , Jiaguo Li , Baoxiu Wang , Jiapeng Chen , Shiqiang Song , Peng Ji","doi":"10.1016/j.polymdegradstab.2025.111537","DOIUrl":"10.1016/j.polymdegradstab.2025.111537","url":null,"abstract":"<div><div>Functional regeneration of waste plastics is a pivotal strategy for sustainable development. This study has developed a method for functional and collaborative upgrading recycling of waste PET. By using chemical alcoholysis and copolymerization techniques, the waste PET is chemically modified into flame-retardant polyester polyols (rFR POL). It is then used as functional soft segments to polymerize, resulting in the synthesis of recycled high transparency, weather-resistant, and flame-retardant thermoplastic polyurethane (rFR TPU). Research shows using rFR POL as a soft segment cuts petroleum-based material use by 57 % in TPU production. And this enhances the transparency, hydrolysis resistance and flame retardancy of TPU films. After 14 days of hydrolysis and thermal weight loss tests, it was found that the molecular weight of rFR50 % TPU remains almost unchanged, with a high T<sub>5wt %</sub> (225 °C). For rFR100 % TPU, the phosphorus content increases to 19,680 ppm, the LOI reaches 35.30 %, and the vertical burning is rated V-0. The flame retardancy mechanism is attributed to the synergistic gas phase and condensed phase flame retardant effects of P-N. The total GWP of this process is 2800 kg CO<sub>2</sub> equivalent, and the total cost is $1342 per ton, which is 37.8 % and 42 % lower than traditional petroleum-based TPU production, respectively. This process reduces polyester fire risks, fundamentally solves functional chain migration and excessive modifier issues. It also achieves upgraded recycling of non-biodegradable polyester, providing an innovative solution for green flame-retardant polymer development.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"241 ","pages":"Article 111537"},"PeriodicalIF":6.3,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144604283","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}