Pub Date : 2025-04-03DOI: 10.1016/j.polymdegradstab.2025.111364
Na-Im Kim , Jeong-Moo Lee , Jong-Sin Moon , Jung-Wook Wee
In this study, the accelerated degradation tests were conducted on PC/ABS blend (50:50) under various combinations of temperature and humidity, 85 °C-85 %RH, 85 °C-45 %RH, 75 °C-65 %RH, 85 °C-dry, 95 °C-dry, and 105 °C-dry conditions. The generation of surface damages were observed in detail, and a quantitative degree of degradation was defined based on the spectroscopic analysis. Also, the master curves correlating the degree of degradation with mechanical properties were constructed. The prediction model for degradation degree and mechanical properties under arbitrary temperature and humidity condition was suggested based on the degradation kinetics, and it was utilized to estimate the degradation behavior of field-weathered samples for 6 months. Based on this study, it is believed that the degradation behavior of PC/ABS blend under a wide range of weathering conditions can be predicted accurately by suggested protocol, and the reliable application potential of PC/ABS blends for various industrial areas is enhanced.
{"title":"Characterization and modeling of weathering degradation of PC/ABS blend in various temperature and humidity conditions","authors":"Na-Im Kim , Jeong-Moo Lee , Jong-Sin Moon , Jung-Wook Wee","doi":"10.1016/j.polymdegradstab.2025.111364","DOIUrl":"10.1016/j.polymdegradstab.2025.111364","url":null,"abstract":"<div><div>In this study, the accelerated degradation tests were conducted on PC/ABS blend (50:50) under various combinations of temperature and humidity, 85 °C-85 %RH, 85 °C-45 %RH, 75 °C-65 %RH, 85 °C-dry, 95 °C-dry, and 105 °C-dry conditions. The generation of surface damages were observed in detail, and a quantitative degree of degradation was defined based on the spectroscopic analysis. Also, the master curves correlating the degree of degradation with mechanical properties were constructed. The prediction model for degradation degree and mechanical properties under arbitrary temperature and humidity condition was suggested based on the degradation kinetics, and it was utilized to estimate the degradation behavior of field-weathered samples for 6 months. Based on this study, it is believed that the degradation behavior of PC/ABS blend under a wide range of weathering conditions can be predicted accurately by suggested protocol, and the reliable application potential of PC/ABS blends for various industrial areas is enhanced.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111364"},"PeriodicalIF":6.3,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143799057","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}
Pub Date : 2025-04-03DOI: 10.1016/j.polymdegradstab.2025.111366
Nina Maria Ainali , Dimitrios N. Bikiaris , Dimitra A. Lambropoulou
The combination of rapid growth in global plastic production and insufficient waste management has led to severe environmental pollution and resource depletion, rendering the degradation of plastics into microplastics (MPs) an intensified concern. Among the different mechanisms driving the MP formation, UV-induced photodegradation holds a crucial role, since it facilitates the initiation of chemical transformation, such as chain scission, oxidation, and crosslinking reactions, which result in physicochemical alterations and fragmentation of polymers. With the most expanded research been conducted on polyolefins, there still remains a gap in understanding the photodegradation mechanisms of other widely used polymer types, such as poly(vinyl chloride) (PVC) and poly(methyl methacrylate) (PMMA). Herein, the UV-B-induced aging of PVC and PMMA thin films was investigated over a two-month period. An inclusive sequence of characterization and analytical techniques, such as Fourier-transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Pyrolysis–Gas Chromatography/Mass Spectrometry (Py–GC/MS), was employed to evaluate the physicochemical, thermal, morphological, and chemical changes of the studied polymers. Significant structural and chemical alterations were found in both studied polymers, underscoring their vulnerability to UV-induced oxidation processes with the FTIR spectra's identification of new oxidation products. While mechanical performance deterioration during UV irradiation suggested the progressive fragmentation of polymers, potentially causing the formation of MPs, SEM images and water contact angle values showed the notable morphological and hydrophilicity changes of the irradiated samples in comparison to the virgin one. Additionally, according to Py–GC/MS analysis, the relative abundance of pyrolysis products changed during the UV exposure testing as well. Furthermore, during photo-aging, there were notable variations in the quantities of pyrolytic marker compounds, which are frequently utilized in MPs analysis in ongoing research. All aspects considered, these results highlight the necessity of deepened research into the aging processes of common polymer types since they present significant obstacles to the precision and reliability of MPs quantification in real environmental samples.
{"title":"Joint physicochemical effects of UV-B irradiation on microplastics formation: The case of poly(vinyl chloride) and poly(methyl methacrylate)","authors":"Nina Maria Ainali , Dimitrios N. Bikiaris , Dimitra A. Lambropoulou","doi":"10.1016/j.polymdegradstab.2025.111366","DOIUrl":"10.1016/j.polymdegradstab.2025.111366","url":null,"abstract":"<div><div>The combination of rapid growth in global plastic production and insufficient waste management has led to severe environmental pollution and resource depletion, rendering the degradation of plastics into microplastics (MPs) an intensified concern. Among the different mechanisms driving the MP formation, UV-induced photodegradation holds a crucial role, since it facilitates the initiation of chemical transformation, such as chain scission, oxidation, and crosslinking reactions, which result in physicochemical alterations and fragmentation of polymers. With the most expanded research been conducted on polyolefins, there still remains a gap in understanding the photodegradation mechanisms of other widely used polymer types, such as poly(vinyl chloride) (PVC) and poly(methyl methacrylate) (PMMA). Herein, the UV-B-induced aging of PVC and PMMA thin films was investigated over a two-month period. An inclusive sequence of characterization and analytical techniques, such as Fourier-transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Pyrolysis–Gas Chromatography/Mass Spectrometry (Py–GC/MS), was employed to evaluate the physicochemical, thermal, morphological, and chemical changes of the studied polymers. Significant structural and chemical alterations were found in both studied polymers, underscoring their vulnerability to UV-induced oxidation processes with the FTIR spectra's identification of new oxidation products. While mechanical performance deterioration during UV irradiation suggested the progressive fragmentation of polymers, potentially causing the formation of MPs, SEM images and water contact angle values showed the notable morphological and hydrophilicity changes of the irradiated samples in comparison to the virgin one. Additionally, according to Py–GC/MS analysis, the relative abundance of pyrolysis products changed during the UV exposure testing as well. Furthermore, during photo-aging, there were notable variations in the quantities of pyrolytic marker compounds, which are frequently utilized in MPs analysis in ongoing research. All aspects considered, these results highlight the necessity of deepened research into the aging processes of common polymer types since they present significant obstacles to the precision and reliability of MPs quantification in real environmental samples.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111366"},"PeriodicalIF":6.3,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143790983","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}
Pub Date : 2025-04-03DOI: 10.1016/j.polymdegradstab.2025.111348
Katrin Markus, Tobias Kirschbaum, Elke Metzsch-Zilligen, Rudolf Pfaendner
Development and evaluation of novel bio-based stabilizers including benzoates, cinnamates and phenyl propionates are presented, focusing on long-term thermal and UV stabilization performance of polypropylene. The synthesized structures include benzoates, cinnamates and phenyl propionate esters. Long-term thermal studies indicated that phenyl propionates provided superior stability compared to other structures. The analysis of carbonyl indices during accelerated aging showed lower values for phenyl propionate additives too, highlighting their effective stabilization capabilities. Double-substituted phenols outperformed mono-substituted ones in mechanical property assessments. Benzoates seem to be the only derivatives to provide some UV stability. Overall, the results suggest that the synthesized bio-based antioxidants could serve as promising alternatives to conventional stabilizers, offering potential benefits for more sustainable applications in various industries.
{"title":"Performance of novel biobased stabilizers: Long-term thermal and UV stability of polypropylene","authors":"Katrin Markus, Tobias Kirschbaum, Elke Metzsch-Zilligen, Rudolf Pfaendner","doi":"10.1016/j.polymdegradstab.2025.111348","DOIUrl":"10.1016/j.polymdegradstab.2025.111348","url":null,"abstract":"<div><div>Development and evaluation of novel bio-based stabilizers including benzoates, cinnamates and phenyl propionates are presented, focusing on long-term thermal and UV stabilization performance of polypropylene. The synthesized structures include benzoates, cinnamates and phenyl propionate esters. Long-term thermal studies indicated that phenyl propionates provided superior stability compared to other structures. The analysis of carbonyl indices during accelerated aging showed lower values for phenyl propionate additives too, highlighting their effective stabilization capabilities. Double-substituted phenols outperformed mono-substituted ones in mechanical property assessments. Benzoates seem to be the only derivatives to provide some UV stability. Overall, the results suggest that the synthesized bio-based antioxidants could serve as promising alternatives to conventional stabilizers, offering potential benefits for more sustainable applications in various industries.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111348"},"PeriodicalIF":6.3,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143815679","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}
As one of the most widely used polymer materials in the world, polyamide 6 (PA6) requires enhanced flame retardancy due to its expanding applications. Here, a reactive flame retardant, P-Ph-N ACL, based on functionalized α-amino-ε-caprolactam is synthesized through a two-step Kabachnik-Fields reaction, using α-amino-ε-caprolactam (ACL), 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), and benzaldehyde as the reactants. As a reactive flame retardant, P-Ph-N ACL exhibits excellent flame-retardant performance, thermal stability, and reactivity. A series of copolymerized flame-retardant polyamide (P-Ph-N PA) are synthesized via hydrolytic copolycondensation using ε-caprolactam (CPL) and P-Ph-N ACL as raw materials. As the amount of the P-Ph-N ACL increases, the flame-retardant performance of P-Ph-N PA improves significantly. When 8 wt% of P-Ph-N ACL is added, the limiting oxygen index (LOI) of P-Ph-N PA-8 increases from 21% for pure PA6 to 35%. In vertical combustion tests, P-Ph-N PA-8 self-extinguishes within 7 s after ignition, achieving the UL94 V-0 rating. The cooperative effects of gas-phase and condensed-phase flame-retardant mode of actions collectively contribute to the enhanced flame retardancy of P-Ph-N PA. Furthermore, P-Ph-N PA-8 maintains a relatively high molecular weight and crystallinity, along with commendable thermal stability and mechanical properties.
{"title":"A reactive flame retardant based on functionalized α-amino-ε-caprolactam with a P-C-N bond structure for copolymerized flame-retardant polyamide","authors":"Rende Qin, Wenxing Yuan, Jiajun Fu, Zixin Zhang, Yongjie Yuan, Hailiang Zhang","doi":"10.1016/j.polymdegradstab.2025.111363","DOIUrl":"10.1016/j.polymdegradstab.2025.111363","url":null,"abstract":"<div><div>As one of the most widely used polymer materials in the world, polyamide 6 (PA6) requires enhanced flame retardancy due to its expanding applications. Here, a reactive flame retardant, P-Ph-N ACL, based on functionalized α-amino-ε-caprolactam is synthesized through a two-step Kabachnik-Fields reaction, using α-amino-ε-caprolactam (ACL), 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), and benzaldehyde as the reactants. As a reactive flame retardant, P-Ph-N ACL exhibits excellent flame-retardant performance, thermal stability, and reactivity. A series of copolymerized flame-retardant polyamide (P-Ph-N PA) are synthesized via hydrolytic copolycondensation using ε-caprolactam (CPL) and P-Ph-N ACL as raw materials. As the amount of the P-Ph-N ACL increases, the flame-retardant performance of P-Ph-N PA improves significantly. When 8 wt% of P-Ph-N ACL is added, the limiting oxygen index (LOI) of P-Ph-N PA-8 increases from 21% for pure PA6 to 35%. In vertical combustion tests, P-Ph-N PA-8 self-extinguishes within 7 s after ignition, achieving the UL94 V-0 rating. The cooperative effects of gas-phase and condensed-phase flame-retardant mode of actions collectively contribute to the enhanced flame retardancy of P-Ph-N PA. Furthermore, P-Ph-N PA-8 maintains a relatively high molecular weight and crystallinity, along with commendable thermal stability and mechanical properties.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111363"},"PeriodicalIF":6.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768899","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}
Pub Date : 2025-04-01DOI: 10.1016/j.polymdegradstab.2025.111342
Judit Rebeka Molnár, Yu-I Hsu, Hiroshi Uyama
The transition to a circular economy requires the development of bio-based polymers with enhanced functionality to compete with conventional oil-sourced materials. In this study, a bio-based furandicarboxylic acid-containing polyester, poly(diethylene furanoate) (PDEF) was directly copolymerized with polylactide (PLA) for the first time, through the polycondensation of dimethyl furan-2,5-dicarboxylate (MFDC) and diethylene glycol (DEG), used as an initiator for the ring-opening polymerization (ROP) of lactide, followed by chain extension reaction with hexamethylene diisocyanate (HDI) to obtain poly(diethylene furanoate)-block-polylactide (PDEF-b-PLA) alternating multiblock copolymers. The PDEF synthesized with different reaction times exhibited an average glass transition temperature (Tg) of 33.8 °C. The copolymers had PLA segment lengths of 1000 and 300 g/mol after ROP maintaining an amorphous structure with a Tg of 34.5 and 33.3 °C respectively, suggesting easy processability. Thermal stability of the copolymers was enhanced, indicated by increased decomposition temperatures and residual weight compared to neat PLA. PDEF displayed elastomer-like behavior while the copolymerization resulted in an intermediate behavior between PDEF and semi-crystalline PLA, with a high Young's modulus of 1.7 and 1.4 GPa, a balanced tensile stress at yield of 24.3 and 28.9 MPa and a significantly increased elongation at break, by 700–1100 % compared to neat PLA. All PDEF-containing samples demonstrated excellent UV-blocking ability due to the furan moiety, effectively blocking UV radiation below 300 nm while maintaining transparency in the visible range. These bio-based PDEF-b-PLA copolymers offer a sustainable alternative for applications such as food packaging and coatings, where thermal stability, mechanical resilience and UV protection are essential.
{"title":"Synthesis of bio-based poly(diethylene furanoate)-block-polylactide copolymers with UV blocking properties","authors":"Judit Rebeka Molnár, Yu-I Hsu, Hiroshi Uyama","doi":"10.1016/j.polymdegradstab.2025.111342","DOIUrl":"10.1016/j.polymdegradstab.2025.111342","url":null,"abstract":"<div><div>The transition to a circular economy requires the development of bio-based polymers with enhanced functionality to compete with conventional oil-sourced materials. In this study, a bio-based furandicarboxylic acid-containing polyester, poly(diethylene furanoate) (PDEF) was directly copolymerized with polylactide (PLA) for the first time, through the polycondensation of dimethyl furan-2,5-dicarboxylate (MFDC) and diethylene glycol (DEG), used as an initiator for the ring-opening polymerization (ROP) of lactide, followed by chain extension reaction with hexamethylene diisocyanate (HDI) to obtain poly(diethylene furanoate)-block-polylactide (PDEF-b-PLA) alternating multiblock copolymers. The PDEF synthesized with different reaction times exhibited an average glass transition temperature (T<sub>g</sub>) of 33.8 °C. The copolymers had PLA segment lengths of 1000 and 300 g/mol after ROP maintaining an amorphous structure with a T<sub>g</sub> of 34.5 and 33.3 °C respectively, suggesting easy processability. Thermal stability of the copolymers was enhanced, indicated by increased decomposition temperatures and residual weight compared to neat PLA. PDEF displayed elastomer-like behavior while the copolymerization resulted in an intermediate behavior between PDEF and semi-crystalline PLA, with a high Young's modulus of 1.7 and 1.4 GPa, a balanced tensile stress at yield of 24.3 and 28.9 MPa and a significantly increased elongation at break, by 700–1100 % compared to neat PLA. All PDEF-containing samples demonstrated excellent UV-blocking ability due to the furan moiety, effectively blocking UV radiation below 300 nm while maintaining transparency in the visible range. These bio-based PDEF-b-PLA copolymers offer a sustainable alternative for applications such as food packaging and coatings, where thermal stability, mechanical resilience and UV protection are essential.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111342"},"PeriodicalIF":6.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738607","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}
Pub Date : 2025-04-01DOI: 10.1016/j.polymdegradstab.2025.111355
Wenjie Guo , Li Li , Junjie Yang , Konghao Yu , Xuecheng Sun , Zhirong Wang , Junling Wang , Jiabao Zhang
Thermoplastic polyurethane (TPU) is widely applied in many fields including construction, cables, automobiles, and aerospace. However, TPU is extremely flammable, endangering people's lives and property. Boron nitride (BN) nanosheets are highly thermally stable, and nano-metal oxides (CoMoO4) are great for catalytic carbonization. Therefore, in this work, CoMoO4 is facilely assembled on the surface of BN, to design three types of BN-CoMo fillers (namely, BN-CoMo-1, BN-CoMo-2, BN-CoMo-3). These fillers are further utilized as flame retardants for TPU, with composites containing 6.0 wt% BN-CoMo-1 being the most effective. Compared with pure TPU, the peak heat release rate (PHRR) is decreased by 51.6%. Meanwhile, BN-CoMo-1 shows substantial benefits in suppressing smoke and CO production. In specific, the peak smoke production rate (PSPR) and peak CO production rate (PCOP) of TPU/6.0 BN-CoMo-1 are decreased by 64.8% and 62.2%. Through a comprehensive assessment, it is further verified that BN-CoMo-1 has outstanding advantages in enhancing the flame retardancy of TPU. Due to the excellent flame retardant and thermal insulation properties of TPU/6.0 BN-CoMo-1, it can be used as the barrier material to inhibit the thermal runaway propagation of batteries.
{"title":"Mechanism Investigation and Safety Evaluation towards Flame-retardant Structural Thermoplastic Polyurethane Composites Inspired via Interfacial Synergy Strategy","authors":"Wenjie Guo , Li Li , Junjie Yang , Konghao Yu , Xuecheng Sun , Zhirong Wang , Junling Wang , Jiabao Zhang","doi":"10.1016/j.polymdegradstab.2025.111355","DOIUrl":"10.1016/j.polymdegradstab.2025.111355","url":null,"abstract":"<div><div>Thermoplastic polyurethane (TPU) is widely applied in many fields including construction, cables, automobiles, and aerospace. However, TPU is extremely flammable, endangering people's lives and property. Boron nitride (BN) nanosheets are highly thermally stable, and nano-metal oxides (CoMoO<sub>4</sub>) are great for catalytic carbonization. Therefore, in this work, CoMoO<sub>4</sub> is facilely assembled on the surface of BN, to design three types of BN-CoMo fillers (namely, BN-CoMo-1, BN-CoMo-2, BN-CoMo-3). These fillers are further utilized as flame retardants for TPU, with composites containing 6.0 wt% BN-CoMo-1 being the most effective. Compared with pure TPU, the peak heat release rate (PHRR) is decreased by 51.6%. Meanwhile, BN-CoMo-1 shows substantial benefits in suppressing smoke and CO production. In specific, the peak smoke production rate (PSPR) and peak CO production rate (PCOP) of TPU/6.0 BN-CoMo-1 are decreased by 64.8% and 62.2%. Through a comprehensive assessment, it is further verified that BN-CoMo-1 has outstanding advantages in enhancing the flame retardancy of TPU. Due to the excellent flame retardant and thermal insulation properties of TPU/6.0 BN-CoMo-1, it can be used as the barrier material to inhibit the thermal runaway propagation of batteries.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111355"},"PeriodicalIF":6.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143799058","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}
As a widely used external insulation for composite insulators, the aging behaviors of high-temperature vulcanized silicone rubber (HTV-SR) in plateau regions are affected by various environmental factors. This study investigates the aging mechanisms of HTV-SR under simulated plateau conditions, considering the ultraviolet B (UVB) and corona coupling effects. By analyzing the surface morphology, structural, mechanical and electrical properties under constant corona voltage and varying UVB levels, the synergistic and competitive effects of these two factors are explored. The results show that pure UVB aging induces mild degradation, characterized by uniform surface oxidation and chalking. Besides, pure corona aging leads to severe localized deterioration, causing uneven oxidation, carbonization, and a reduction in flashover voltage. Under combined aging, intense UVB exposure accelerates crack propagation and carbonization due to rapid oxygen depletion, increasing crosslink density and interfacial polarization. In contrast, weak UVB exposure prioritizes oxygen consumption, suppresses corona aging, promotes uniform oxidation and reduces trap energy levels, improving surface resistivity. Further analysis based on quantum chemistry calculations reveals the uniform crosslinking surface formed under weak UVB has shallow traps, which improves the electrical properties. Finally, the elongation at break of artificially and naturally aged HTV-SR are compared, validating the effectiveness of the artificial aging method. This study provides valuable insights into the weather resistance and lifespan assessment of HTV-SR, contributing to improved reliability and durability of composite insulators in plateau environments.
{"title":"Degradation of HTV silicone rubber in composite insulators under UVB-corona coupling effect in simulated plateau environments","authors":"Shiyin Zeng, Wendong Li, Xin Zhao, Yanan Peng, Yuelin Liu, Xinyi Yan, Guanjun Zhang","doi":"10.1016/j.polymdegradstab.2025.111354","DOIUrl":"10.1016/j.polymdegradstab.2025.111354","url":null,"abstract":"<div><div>As a widely used external insulation for composite insulators, the aging behaviors of high-temperature vulcanized silicone rubber (HTV-SR) in plateau regions are affected by various environmental factors. This study investigates the aging mechanisms of HTV-SR under simulated plateau conditions, considering the ultraviolet B (UVB) and corona coupling effects. By analyzing the surface morphology, structural, mechanical and electrical properties under constant corona voltage and varying UVB levels, the synergistic and competitive effects of these two factors are explored. The results show that pure UVB aging induces mild degradation, characterized by uniform surface oxidation and chalking. Besides, pure corona aging leads to severe localized deterioration, causing uneven oxidation, carbonization, and a reduction in flashover voltage. Under combined aging, intense UVB exposure accelerates crack propagation and carbonization due to rapid oxygen depletion, increasing crosslink density and interfacial polarization. In contrast, weak UVB exposure prioritizes oxygen consumption, suppresses corona aging, promotes uniform oxidation and reduces trap energy levels, improving surface resistivity. Further analysis based on quantum chemistry calculations reveals the uniform crosslinking surface formed under weak UVB has shallow traps, which improves the electrical properties. Finally, the elongation at break of artificially and naturally aged HTV-SR are compared, validating the effectiveness of the artificial aging method. This study provides valuable insights into the weather resistance and lifespan assessment of HTV-SR, contributing to improved reliability and durability of composite insulators in plateau environments.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111354"},"PeriodicalIF":6.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143799701","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}
Pub Date : 2025-03-31DOI: 10.1016/j.polymdegradstab.2025.111353
Wen-Long Mu, Jin-Nuo Wang, Bin Zhao, Ying-Jun Xu
Inherent flammability of unsaturated polyester (UP) resins restricts their application in fields requiring high flame retardancy. Traditional flame retardants often compromise the resin's performance and involve complex processing procedures. In this study, a 1-vinylimidazole phosphite salt (called VIP) was developed for UP systems as a flame-retardant crosslinking agent. VIP can covalently bond with UP's unsaturated bonds and integrate with phosphorous acids through ionic interactions, ensuring good compatibility, high curing activity, and superior processing performance. With 15 wt % additions of VIP, the cured UP (15VIP/UP) achieved the UL 94 V0 rating with a limiting oxygen index of 29.4 %. Cone calorimetry results showed significant reductions of 15VIP/UP in the peak heat release (66.6 %) and smoke production rate (59.3 %) compared to unmodified UP. Char residue and pyrolysis analyses revealed that VIP promoted the formation of a dense protective char layer, while effectively suppressing the release of flammable gases and smoke. Additionally, the introduction of VIP did not significantly deteriorate thermal and mechanical performance of UP. This study introduces a facile and efficient strategy that achieves high flame retardancy and superior performance in UP through ionic bonding of flame-retardant groups.
{"title":"Flame retardancy and smoke suppression of unsaturated polyester resins enabled by 1-vinylimidazole phosphite salts","authors":"Wen-Long Mu, Jin-Nuo Wang, Bin Zhao, Ying-Jun Xu","doi":"10.1016/j.polymdegradstab.2025.111353","DOIUrl":"10.1016/j.polymdegradstab.2025.111353","url":null,"abstract":"<div><div>Inherent flammability of unsaturated polyester (UP) resins restricts their application in fields requiring high flame retardancy. Traditional flame retardants often compromise the resin's performance and involve complex processing procedures. In this study, a 1-vinylimidazole phosphite salt (called VIP) was developed for UP systems as a flame-retardant crosslinking agent. VIP can covalently bond with UP's unsaturated bonds and integrate with phosphorous acids through ionic interactions, ensuring good compatibility, high curing activity, and superior processing performance. With 15 wt % additions of VIP, the cured UP (15VIP/UP) achieved the UL 94 V0 rating with a limiting oxygen index of 29.4 %. Cone calorimetry results showed significant reductions of 15VIP/UP in the peak heat release (66.6 %) and smoke production rate (59.3 %) compared to unmodified UP. Char residue and pyrolysis analyses revealed that VIP promoted the formation of a dense protective char layer, while effectively suppressing the release of flammable gases and smoke. Additionally, the introduction of VIP did not significantly deteriorate thermal and mechanical performance of UP. This study introduces a facile and efficient strategy that achieves high flame retardancy and superior performance in UP through ionic bonding of flame-retardant groups.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111353"},"PeriodicalIF":6.3,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143790980","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}
Pub Date : 2025-03-29DOI: 10.1016/j.polymdegradstab.2025.111349
Rainie Cherian, C.J. Binish, Vijayasankar A V
Plastic waste pollution causes significant environmental challenges, contributing to environmental deterioration and severe impact on human health. Addressing this issue, Metal-Organic Framework (MOF) has appeared as a dynamic and eco-friendly material used for the degradation of plastics and organic pollutants. MOFs exhibit exceptional structural properties like high surface area, porosity that are being widely used in catalytic and adsorption-based applications. This review explores the advancement in MOF and their use as catalysts for the degradation of polymers from the early 2010s. It highlights the innovative upcycling of PET waste into MOFs, promoting a circular economy while mitigating ecological concerns. Moreover, the review also reinforces the degradation mechanism, challenges and limitation of MOFs, including their stability, recyclability, and cost-efficiency in extensive scale application. Combining MOFs into aerogels or employing post-synthetic modification are some ways to enhance their durability and performance. Advanced techniques, such as computational simulations and AI-based design, are being developed to revolutionize MOF optimization for different applications. It also emphasizes their potential to tackle plastic pollution and facilitate eco-innovations in environmental remediation and polymer recycling.
{"title":"Eco-Frameworks for a Cleaner Planet: Harnessing Next-Gen MOFs for Pollution and Plastic Waste Remediation","authors":"Rainie Cherian, C.J. Binish, Vijayasankar A V","doi":"10.1016/j.polymdegradstab.2025.111349","DOIUrl":"10.1016/j.polymdegradstab.2025.111349","url":null,"abstract":"<div><div>Plastic waste pollution causes significant environmental challenges, contributing to environmental deterioration and severe impact on human health. Addressing this issue, Metal-Organic Framework (MOF) has appeared as a dynamic and eco-friendly material used for the degradation of plastics and organic pollutants. MOFs exhibit exceptional structural properties like high surface area, porosity that are being widely used in catalytic and adsorption-based applications. This review explores the advancement in MOF and their use as catalysts for the degradation of polymers from the early 2010s. It highlights the innovative upcycling of PET waste into MOFs, promoting a circular economy while mitigating ecological concerns. Moreover, the review also reinforces the degradation mechanism, challenges and limitation of MOFs, including their stability, recyclability, and cost-efficiency in extensive scale application. Combining MOFs into aerogels or employing post-synthetic modification are some ways to enhance their durability and performance. Advanced techniques, such as computational simulations and AI-based design, are being developed to revolutionize MOF optimization for different applications. It also emphasizes their potential to tackle plastic pollution and facilitate eco-innovations in environmental remediation and polymer recycling.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111349"},"PeriodicalIF":6.3,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768900","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}
Pub Date : 2025-03-29DOI: 10.1016/j.polymdegradstab.2025.111352
Mingli Wang , Ziyu Liu , Tiancheng Wang , Jiahao Ma , Jue Cheng , Xiaoqing Liu , Junying Zhang
The deterioration of epoxy resin properties caused by UV radiation is a major bottleneck in the epoxy resin applications development. And, its mechanism is UV-induced chemical bond breaking and the stress concentration resulting from the structural changes in the crosslinked network. However, the strategy to improve UV aging resistance have always been unsatisfactory, as the integrity of the chemical bond has been overemphasized and the failure caused by the stress concentration has been neglected. Herein, an epoxy crosslinked network containing two photosensitive groups, anthracene and disulfide, was prepared. Among them, anthracene can absorb UVA wavelength light and proceed [4 + 4] cycloaddition reaction, so as to compensate for the damage of chemical crosslinked structure; thanks to the chain segment rapid relaxation during annealing, the dynamic disulfide bonds can not only absorb and shield UV light, but also greatly avoid the stress concentration. After 600 h (actual UV exposure time 400 h) simulated UV aging (340 nm, 0.76 W·m-2), the tensile strength and fracture toughness decreased by only -2.6 % and -18.9 %, which showed excellent performance retention after UV aging, compared with the control sample. This study will provide important guidance for the structure and formulation design of UV-resistant aging resins.
{"title":"Insights into the effect of segment rearrangement induced by dynamic disulfide bond on UV aging resistance of UV-induced self-compensated epoxy crosslinked network","authors":"Mingli Wang , Ziyu Liu , Tiancheng Wang , Jiahao Ma , Jue Cheng , Xiaoqing Liu , Junying Zhang","doi":"10.1016/j.polymdegradstab.2025.111352","DOIUrl":"10.1016/j.polymdegradstab.2025.111352","url":null,"abstract":"<div><div>The deterioration of epoxy resin properties caused by UV radiation is a major bottleneck in the epoxy resin applications development. And, its mechanism is UV-induced chemical bond breaking and the stress concentration resulting from the structural changes in the crosslinked network. However, the strategy to improve UV aging resistance have always been unsatisfactory, as the integrity of the chemical bond has been overemphasized and the failure caused by the stress concentration has been neglected. Herein, an epoxy crosslinked network containing two photosensitive groups, anthracene and disulfide, was prepared. Among them, anthracene can absorb UVA wavelength light and proceed [4 + 4] cycloaddition reaction, so as to compensate for the damage of chemical crosslinked structure; thanks to the chain segment rapid relaxation during annealing, the dynamic disulfide bonds can not only absorb and shield UV light, but also greatly avoid the stress concentration. After 600 h (actual UV exposure time 400 h) simulated UV aging (340 nm, 0.76 W·m<sup>-2</sup>), the tensile strength and fracture toughness decreased by only -2.6 % and -18.9 %, which showed excellent performance retention after UV aging, compared with the control sample. This study will provide important guidance for the structure and formulation design of UV-resistant aging resins.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"238 ","pages":"Article 111352"},"PeriodicalIF":6.3,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143760965","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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