Pub Date : 2024-11-07DOI: 10.1016/j.polymdegradstab.2024.111057
Xiang Ao , Robert Crouse , Gloria Guerrero-Muñoz , De-Yi Wang
The natural abundance, biodegradability, and low density of plant fibers, together with biobased epoxy thermoset resin, have driven the increasing popularity of plant fiber/polymer composites (PFRPs) to wider applications in various industries. However, the striving for biomass-based flame retardants (FRs) treatment for PFRPs remained a bottleneck due to polymers’ inherent vulnerability against fire and the increasing environmental awareness. In this work, a facile two-step aqueous solution coating process was proposed for fabric surface treatment of flax fabric using fully biobased phytic acid and chitosan from polysaccharides. The treated flax fabric demonstrated self-extinguishing behavior when ignited and showed a decrease in peak heat release rate (PHRR) by 58% under combustion. The laminate produced by this treated flax fabric and biobased epoxy resin showed a decrease of PHRR by 36% and an increase of more than 200% for the time of torch fire burn-through, demonstrating intriguing flame retardance brought by only FRs treatment on flax fabric reinforcements. Various measurements were done to elaborate on the role of treated flax fabric in the flame retardancy of polymer composites.
{"title":"A facile biomass-based coating for flax fabric toward plant fiber/biobased epoxy composite with enhanced fire safety","authors":"Xiang Ao , Robert Crouse , Gloria Guerrero-Muñoz , De-Yi Wang","doi":"10.1016/j.polymdegradstab.2024.111057","DOIUrl":"10.1016/j.polymdegradstab.2024.111057","url":null,"abstract":"<div><div>The natural abundance, biodegradability, and low density of plant fibers, together with biobased epoxy thermoset resin, have driven the increasing popularity of plant fiber/polymer composites (PFRPs) to wider applications in various industries. However, the striving for biomass-based flame retardants (FRs) treatment for PFRPs remained a bottleneck due to polymers’ inherent vulnerability against fire and the increasing environmental awareness. In this work, a facile two-step aqueous solution coating process was proposed for fabric surface treatment of flax fabric using fully biobased phytic acid and chitosan from polysaccharides. The treated flax fabric demonstrated self-extinguishing behavior when ignited and showed a decrease in peak heat release rate (PHRR) by 58% under combustion. The laminate produced by this treated flax fabric and biobased epoxy resin showed a decrease of PHRR by 36% and an increase of more than 200% for the time of torch fire burn-through, demonstrating intriguing flame retardance brought by only FRs treatment on flax fabric reinforcements. Various measurements were done to elaborate on the role of treated flax fabric in the flame retardancy of polymer composites.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"231 ","pages":"Article 111057"},"PeriodicalIF":6.3,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142699865","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 : 2024-11-06DOI: 10.1016/j.polymdegradstab.2024.111079
Yuqing Dai , Rongjia Wen , Chunyan Zhao , Ahmed Al-Mansour , Chengji Xu , Le Li , Qiang Zeng , Kefei Li , Qinghua Li , Shilang Xu
Epoxy-based coatings are widely used in engineering but are prone to degrade under aggressive environmental actions, especially in hygrothermal environments. However, the degradation mechanisms of a coating-substrate system under coupled UV irradiation and bulk water remain insufficiently explored. Herein, we designed three parallel accelerated aging tests, including UV irradiation only, UV/flush, and UV/submerged, on a waterborne epoxy resin (WER) coating on cement mortar substrate. The chemical structure, micro-morphology, and hydrophilicity over aging time were comprehensively characterized by the tests of attenuated total reflectance Fourier transformation infrared spectrometer (ATR-FTIR), scanning electron microscopy (SEM), image analysis, water contact angle (WCA). Results show that the UV/flush environments induced more micro-pinholes on the WER outer surface than the neat UV photooxidation. The UV/ submerged environment led to a blistering rate over 24% after 60 d's exposure owing to the significant osmotic pressure built between the inner and outer surfaces of the WER coating. Additionally, the physicochemical and microstructure changes to the outer surface of WER also caused the changes of WCA. The osmotic, hydrolysis, and thermal stresses were evaluated to clarify the water-accelerated photooxidation and interface degradation mechanisms. These findings contribute to a deeper understanding of epoxy coating degradation mechanisms in response to environmental stressors, and offer insights for enhancing coating performance under varying conditions.
环氧基涂料广泛应用于工程领域，但在侵蚀性环境作用下，尤其是在湿热环境中，容易发生降解。然而，涂层-基底系统在紫外线辐照和散水耦合作用下的降解机理仍未得到充分探索。在此，我们对水泥砂浆基材上的水性环氧树脂（WER）涂层设计了三种平行加速老化试验，包括仅紫外线照射、紫外线/冲洗和紫外线/浸泡。通过衰减全反射傅立叶变换红外光谱仪（ATR-FTIR）、扫描电子显微镜（SEM）、图像分析、水接触角（WCA）等测试，对老化时间内的化学结构、微观形态和亲水性进行了综合表征。结果表明，与纯紫外光氧化相比，紫外/冲洗环境在 WER 外表面诱发了更多的微针孔。由于 WER 涂层内外表面之间形成了巨大的渗透压，紫外线/浸没环境在暴露 60 天后导致起泡率超过 24%。此外，WER 外表面的物理化学和微观结构变化也导致了 WCA 的变化。通过对渗透、水解和热应力的评估，阐明了水加速光氧化和界面降解的机理。这些发现有助于加深对环氧涂层在环境应力作用下降解机理的理解，并为在不同条件下提高涂层性能提供了启示。
{"title":"Distinct photooxidation and interface degradation of waterborne epoxy resin coatings on mortar substrate affected by bulk water","authors":"Yuqing Dai , Rongjia Wen , Chunyan Zhao , Ahmed Al-Mansour , Chengji Xu , Le Li , Qiang Zeng , Kefei Li , Qinghua Li , Shilang Xu","doi":"10.1016/j.polymdegradstab.2024.111079","DOIUrl":"10.1016/j.polymdegradstab.2024.111079","url":null,"abstract":"<div><div>Epoxy-based coatings are widely used in engineering but are prone to degrade under aggressive environmental actions, especially in hygrothermal environments. However, the degradation mechanisms of a coating-substrate system under coupled UV irradiation and bulk water remain insufficiently explored. Herein, we designed three parallel accelerated aging tests, including UV irradiation only, UV/flush, and UV/submerged, on a waterborne epoxy resin (WER) coating on cement mortar substrate. The chemical structure, micro-morphology, and hydrophilicity over aging time were comprehensively characterized by the tests of attenuated total reflectance Fourier transformation infrared spectrometer (ATR-FTIR), scanning electron microscopy (SEM), image analysis, water contact angle (WCA). Results show that the UV/flush environments induced more micro-pinholes on the WER outer surface than the neat UV photooxidation. The UV/ submerged environment led to a blistering rate over 24% after 60 d's exposure owing to the significant osmotic pressure built between the inner and outer surfaces of the WER coating. Additionally, the physicochemical and microstructure changes to the outer surface of WER also caused the changes of WCA. The osmotic, hydrolysis, and thermal stresses were evaluated to clarify the water-accelerated photooxidation and interface degradation mechanisms. These findings contribute to a deeper understanding of epoxy coating degradation mechanisms in response to environmental stressors, and offer insights for enhancing coating performance under varying conditions.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"230 ","pages":"Article 111079"},"PeriodicalIF":6.3,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654169","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 : 2024-11-06DOI: 10.1016/j.polymdegradstab.2024.111078
Yangwen Mao , Wenbo Wang , Wanyu Huang , Haopeng Cai
For the purpose of investigating the modified flame-retardant epoxy resin (FREP) with the low smoke density release during combustion, the flame retardant containing P/N/B elements named DBT was synthesized with the raw materials of 4-Acetylphenylboronic acid, 3,5-diaminotriazole and DOPO. The DBT was added as a co-curing agent to an amine-cured epoxy resin system, and based on the DSC results of the resin, it was revealed that -NH- in the structure of the DBT was capable of facilitating EP curing. With the introduction of DBT, the transparency of FREP samples was slightly affected. On account of the excellent flame retardancy exerted by the DBT in the FREP system, the FREP samples reached the V-0 grade in UL-94 testing with an LOI of 35.9% at 5 wt% DBT addition. Meanwhile, the results of the cone calorimetry test demonstrated that in comparison with the epoxy resin, the PHRR, THR and av-EHC of the EP/DBT7.5 sample decreased by 34.0%, 35.4% and 18.68%, respectively. The DBT was effective in reducing the smoke density of EP, and the EP/DBT7.5 sample attained the HL1 level for DS (4) and VOF4. The chemical analyses for residual char revealed that DBT was mainly employed for flame retardancy and smoke suppression by forming P/B-containing chars in the condensed phase. There was no loss of mechanical properties of the FREP samples as the rigid groups were present in the DBT structure. Furthermore, it was noted that the FREP samples exhibited a decrease in dielectric loss and dielectric constant as the content increased.
{"title":"Flame retardant, transparent, low dielectric and low smoke density EP composites implemented with reactive flame retardants containing P/N/B","authors":"Yangwen Mao , Wenbo Wang , Wanyu Huang , Haopeng Cai","doi":"10.1016/j.polymdegradstab.2024.111078","DOIUrl":"10.1016/j.polymdegradstab.2024.111078","url":null,"abstract":"<div><div>For the purpose of investigating the modified flame-retardant epoxy resin (FREP) with the low smoke density release during combustion, the flame retardant containing P/N/B elements named DBT was synthesized with the raw materials of 4-Acetylphenylboronic acid, 3,5-diaminotriazole and DOPO. The DBT was added as a co-curing agent to an amine-cured epoxy resin system, and based on the DSC results of the resin, it was revealed that -NH- in the structure of the DBT was capable of facilitating EP curing. With the introduction of DBT, the transparency of FREP samples was slightly affected. On account of the excellent flame retardancy exerted by the DBT in the FREP system, the FREP samples reached the V-0 grade in UL-94 testing with an LOI of 35.9% at 5 wt% DBT addition. Meanwhile, the results of the cone calorimetry test demonstrated that in comparison with the epoxy resin, the PHRR, THR and av-EHC of the EP/DBT7.5 sample decreased by 34.0%, 35.4% and 18.68%, respectively. The DBT was effective in reducing the smoke density of EP, and the EP/DBT7.5 sample attained the HL1 level for D<sub>S</sub> (4) and VOF<sub>4</sub>. The chemical analyses for residual char revealed that DBT was mainly employed for flame retardancy and smoke suppression by forming P/B-containing chars in the condensed phase. There was no loss of mechanical properties of the FREP samples as the rigid groups were present in the DBT structure. Furthermore, it was noted that the FREP samples exhibited a decrease in dielectric loss and dielectric constant as the content increased.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"230 ","pages":"Article 111078"},"PeriodicalIF":6.3,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654261","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 : 2024-11-06DOI: 10.1016/j.polymdegradstab.2024.111077
Kai Dong, Shasha Tang, Di Zhao, Yang Pang, Chengji Zhao
Incorporating reversible covalent bonds into the crosslinked matrix of bio-based epoxy resins can address the challenges of difficult degradation and sustainable development associated with petroleum-based epoxy resins. However, the dynamic capability conferred by a single dynamic chemical bond proves relatively insufficient in thermosetting polymers. Therefore, we propose a strategy to introduce proportionally adjustable dual dynamic covalent bonds in the bio-based epoxy resin system to leverage the advantages of different dynamic bonds and improve the dynamic properties of the resulting epoxy vitrimers in this study. First, a bio-based epoxy monomer (BVF-EP) derived from vanillin was prepared and cured with a diamine hardener (AFD). Subsequently, vanillin-derived epoxy vitrimers were prepared by varying the stoichiometric ratio of AFD to BVF-EP (R = 0.5, 1.0, and 1.5) without catalysts. Some of the vitrimers showed good thermal stability and excellent reprocessability and degradability. Notably, BVF-EP/AFD (R = 1.5) containing both dynamic reversible covalent bonds of S-S and C=N with the highest crosslink density, exhibited the highest thermal decomposition temperature, highest tensile modulus (7175 MPa), and the shortest stress relaxation time (6 s at 200 ℃). Simultaneously, BVF-EP/AFD (R = 1.5) demonstrated good multiple reprocessing capacity under a pressure of 5 MPa at 140 ℃. It can be completely degraded in two distinct mixed solutions (50 % DMF/50 % β-ME and 50 % 1 M HCl/50 % DMF), offering great potential in recovering high-value carbon fibers from its carbon fiber-reinforced composites. This work advances the development of bio-based epoxy resins with dual dynamic crosslinked networks, providing new insights for the degradation and reprocessing of thermoset polymers.
{"title":"Vanillin-derived bio-based epoxy resins containing dual dynamic Schiff base and disulfide bonds with reprocessability and degradability","authors":"Kai Dong, Shasha Tang, Di Zhao, Yang Pang, Chengji Zhao","doi":"10.1016/j.polymdegradstab.2024.111077","DOIUrl":"10.1016/j.polymdegradstab.2024.111077","url":null,"abstract":"<div><div>Incorporating reversible covalent bonds into the crosslinked matrix of bio-based epoxy resins can address the challenges of difficult degradation and sustainable development associated with petroleum-based epoxy resins. However, the dynamic capability conferred by a single dynamic chemical bond proves relatively insufficient in thermosetting polymers. Therefore, we propose a strategy to introduce proportionally adjustable dual dynamic covalent bonds in the bio-based epoxy resin system to leverage the advantages of different dynamic bonds and improve the dynamic properties of the resulting epoxy vitrimers in this study. First, a bio-based epoxy monomer (BVF-EP) derived from vanillin was prepared and cured with a diamine hardener (AFD). Subsequently, vanillin-derived epoxy vitrimers were prepared by varying the stoichiometric ratio of AFD to BVF-EP (<em>R</em> = 0.5, 1.0, and 1.5) without catalysts. Some of the vitrimers showed good thermal stability and excellent reprocessability and degradability. Notably, BVF-EP/AFD (<em>R</em> = 1.5) containing both dynamic reversible covalent bonds of S-S and C=N with the highest crosslink density, exhibited the highest thermal decomposition temperature, highest tensile modulus (7175 MPa), and the shortest stress relaxation time (6 s at 200 ℃). Simultaneously, BVF-EP/AFD (<em>R</em> = 1.5) demonstrated good multiple reprocessing capacity under a pressure of 5 MPa at 140 ℃. It can be completely degraded in two distinct mixed solutions (50 % DMF/50 % <em>β</em>-ME and 50 % 1 M HCl/50 % DMF), offering great potential in recovering high-value carbon fibers from its carbon fiber-reinforced composites. This work advances the development of bio-based epoxy resins with dual dynamic crosslinked networks, providing new insights for the degradation and reprocessing of thermoset polymers.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"230 ","pages":"Article 111077"},"PeriodicalIF":6.3,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654268","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 : 2024-11-05DOI: 10.1016/j.polymdegradstab.2024.111074
Xiaorong He, Zhou Zhang, Teng Ren, Xinyan Yue, Shifeng Wang
Thermo-oxidative degradation of tire rubber has been demonstrated as a green method for upcycling waste tire rubber. However, the complicated tire compositions present challenges to achieving the homogeneity and efficiency of the reclaimed products, which restricts their widespread industrial adoption. To address this challenge, natural rubber(NR)and natural rubber/butadiene rubber(NR/BR)were innovatively designed to simulate complex tire compositions and investigate the influence of oxygen diffusion on thermo-oxidative degradation at 150–240 °C. The evolution of chemical structural changes and mechanical properties during degradation was traced by FTIR, UV–vis, and nanoindentation test. A basic reactive-diffusion model based on Fickian oxygen diffusion was used to simulate the diffusion profiles. It was found that recrosslinking decreases the oxygen permeability coefficient during NR/BR degradation as the temperature increases, making it difficult for oxygen to diffuse into the inner layer, and therefore tire rubber degrades unevenly. Lower temperatures and prolonged treatment times were recommended to enhance degradation. These findings provide substantial guidance for optimizing the recycling process of tire rubber and its sustainable utilization.
轮胎橡胶的热氧化降解已被证明是废旧轮胎橡胶升级再利用的一种绿色方法。然而，复杂的轮胎成分给实现再生产品的均匀性和效率带来了挑战，限制了其在工业中的广泛应用。为应对这一挑战，研究人员创新性地设计了天然橡胶（NR）和天然橡胶/丁二烯橡胶（NR/BR），模拟复杂的轮胎成分，并研究了氧气扩散对 150-240 °C 下热氧化降解的影响。通过傅立叶变换红外光谱（FTIR）、紫外可见光谱（UV-vis）和纳米压痕测试，对降解过程中化学结构变化和机械性能的演变进行了追踪。采用基于费克氧扩散的基本反应扩散模型模拟了扩散曲线。研究发现，随着温度的升高，再交联会降低 NR/BR 降解过程中的氧气渗透系数，使氧气难以扩散到内层，因此轮胎橡胶的降解不均匀。建议降低温度并延长处理时间，以促进降解。这些发现为优化轮胎橡胶的回收过程及其可持续利用提供了重要指导。
{"title":"Oxygen diffusion effects in thermo-oxidative degradation of typical tire rubber","authors":"Xiaorong He, Zhou Zhang, Teng Ren, Xinyan Yue, Shifeng Wang","doi":"10.1016/j.polymdegradstab.2024.111074","DOIUrl":"10.1016/j.polymdegradstab.2024.111074","url":null,"abstract":"<div><div>Thermo-oxidative degradation of tire rubber has been demonstrated as a green method for upcycling waste tire rubber. However, the complicated tire compositions present challenges to achieving the homogeneity and efficiency of the reclaimed products, which restricts their widespread industrial adoption. To address this challenge, natural rubber(NR)and natural rubber/butadiene rubber(NR/BR)were innovatively designed to simulate complex tire compositions and investigate the influence of oxygen diffusion on thermo-oxidative degradation at 150–240 °C. The evolution of chemical structural changes and mechanical properties during degradation was traced by FTIR, UV–vis, and nanoindentation test. A basic reactive-diffusion model based on Fickian oxygen diffusion was used to simulate the diffusion profiles. It was found that recrosslinking decreases the oxygen permeability coefficient during NR/BR degradation as the temperature increases, making it difficult for oxygen to diffuse into the inner layer, and therefore tire rubber degrades unevenly. Lower temperatures and prolonged treatment times were recommended to enhance degradation. These findings provide substantial guidance for optimizing the recycling process of tire rubber and its sustainable utilization.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"230 ","pages":"Article 111074"},"PeriodicalIF":6.3,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654170","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 : 2024-11-05DOI: 10.1016/j.polymdegradstab.2024.111076
Marc Vermeulen , Samuel P. Johns , Gwen dePolo , Pedro Maximo Rocha , Matthew J. Collins , Lora Angelova , Mélanie Roffet-Salque
To assess the short and long-term effect of a newly developed minimally invasive lipid extraction method on parchment, sacrificial pieces of parchments were subjected to artificial ageing and investigated using various analytical methods. Lipids were extracted using our novel vacuum-aided extraction method and characterised by high-temperature gas chromatography (HTGC-FID). Lipids were identified as arising from degraded animal fats. The physical, molecular, and mechanical properties of the parchment samples before/after lipid extraction, and before/after ageing were assessed using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and pure shear single notch fracture testing. SEM imaging allowed for an assessment of potential structural changes of the collagen fibres while FTIR was used to investigate the possible molecular changes indicated by changes in amide I and II bands. Mechanical tests were used to record the changes in brittleness and stiffness occurring in the materials through lipid extraction and ageing. The multimodal investigation did not highlight measurable changes in the structural, molecular, and mechanical properties of the lipid-extracted parchment, thus indicating the suitability for the minimally invasive lipid extraction method to be applied to historical parchments.
为了评估新开发的微创脂质提取方法对羊皮纸的短期和长期影响，我们对羊皮纸牺牲品进行了人工老化，并使用各种分析方法对其进行了研究。我们采用新颖的真空辅助提取法提取脂质，并通过高温气相色谱法（HTGC-FID）进行表征。经鉴定，脂质来自降解的动物脂肪。使用扫描电子显微镜 (SEM)、傅立叶变换红外光谱 (FTIR) 和纯剪切单缺口断裂测试评估了羊皮纸样品在脂质提取前后和老化前后的物理、分子和机械性能。扫描电子显微镜成像可评估胶原纤维的潜在结构变化，而傅立叶变换红外光谱则用于研究酰胺 I 和 II 波段变化所显示的可能的分子变化。机械测试用于记录材料在脂质提取和老化过程中发生的脆性和硬度变化。多模态调查并未突出显示提取脂质的羊皮纸在结构、分子和机械性能方面发生了可测量的变化，从而表明微创脂质提取方法适用于历史悠久的羊皮纸。
{"title":"Assessing the effect of minimally invasive lipid extraction on parchment integrity by artificial ageing and integrated analytical techniques","authors":"Marc Vermeulen , Samuel P. Johns , Gwen dePolo , Pedro Maximo Rocha , Matthew J. Collins , Lora Angelova , Mélanie Roffet-Salque","doi":"10.1016/j.polymdegradstab.2024.111076","DOIUrl":"10.1016/j.polymdegradstab.2024.111076","url":null,"abstract":"<div><div>To assess the short and long-term effect of a newly developed minimally invasive lipid extraction method on parchment, sacrificial pieces of parchments were subjected to artificial ageing and investigated using various analytical methods. Lipids were extracted using our novel vacuum-aided extraction method and characterised by high-temperature gas chromatography (HTGC-FID). Lipids were identified as arising from degraded animal fats. The physical, molecular, and mechanical properties of the parchment samples before/after lipid extraction, and before/after ageing were assessed using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and pure shear single notch fracture testing. SEM imaging allowed for an assessment of potential structural changes of the collagen fibres while FTIR was used to investigate the possible molecular changes indicated by changes in amide I and II bands. Mechanical tests were used to record the changes in brittleness and stiffness occurring in the materials through lipid extraction and ageing. The multimodal investigation did not highlight measurable changes in the structural, molecular, and mechanical properties of the lipid-extracted parchment, thus indicating the suitability for the minimally invasive lipid extraction method to be applied to historical parchments.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"230 ","pages":"Article 111076"},"PeriodicalIF":6.3,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654259","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 : 2024-11-05DOI: 10.1016/j.polymdegradstab.2024.111058
Kazem Sabet-Bokati, Kevin Plucknett
Among the various strategies implemented to improve the integrity of metallic structures, polymer coatings have emerged as a compelling choice due to their capacity to offer cost-effective and enduring protection. However, humidity is a critical environmental factor that poses a risk to the integrity of polymer coatings, manifesting in dimensional alterations, induced internal stresses, diminished adhesion strength between coating and substrate, microstructural changes, and hydrolytic degradation. Many of these detrimental changes remain concealed until the advanced stages of coating failure. Comprehending the water-induced degradation mechanisms in polymer coatings is crucial for improving their protective effectiveness, ensuring safety and dependability, minimizing economic and environmental impacts, and promoting innovation and regulatory compliance. This study rigorously explores the water-induced failure mechanisms in polymeric coatings, highlighting both visible signs of degradation, such as corrosion, cathodic delamination, and blistering, and less apparent phenomena like hydrolysis, swelling, and plasticization. From the initial stages of water diffusion to the eventual delamination of the coating, diffusion mechanisms and the interaction between water molecules and coating constituents are scrutinized. Moreover, this review explores the distinctive and interrelated impacts of each phenomenon on the integrity of the coating, along with potential mitigation strategies. The review culminates with practical recommendations aimed at bolstering the integrity of coated structures.
{"title":"Water-induced failure in polymer coatings: Mechanisms, impacts and mitigation strategies—A comprehensive review","authors":"Kazem Sabet-Bokati, Kevin Plucknett","doi":"10.1016/j.polymdegradstab.2024.111058","DOIUrl":"10.1016/j.polymdegradstab.2024.111058","url":null,"abstract":"<div><div>Among the various strategies implemented to improve the integrity of metallic structures, polymer coatings have emerged as a compelling choice due to their capacity to offer cost-effective and enduring protection. However, humidity is a critical environmental factor that poses a risk to the integrity of polymer coatings, manifesting in dimensional alterations, induced internal stresses, diminished adhesion strength between coating and substrate, microstructural changes, and hydrolytic degradation. Many of these detrimental changes remain concealed until the advanced stages of coating failure. Comprehending the water-induced degradation mechanisms in polymer coatings is crucial for improving their protective effectiveness, ensuring safety and dependability, minimizing economic and environmental impacts, and promoting innovation and regulatory compliance. This study rigorously explores the water-induced failure mechanisms in polymeric coatings, highlighting both visible signs of degradation, such as corrosion, cathodic delamination, and blistering, and less apparent phenomena like hydrolysis, swelling, and plasticization. From the initial stages of water diffusion to the eventual delamination of the coating, diffusion mechanisms and the interaction between water molecules and coating constituents are scrutinized. Moreover, this review explores the distinctive and interrelated impacts of each phenomenon on the integrity of the coating, along with potential mitigation strategies. The review culminates with practical recommendations aimed at bolstering the integrity of coated structures.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"230 ","pages":"Article 111058"},"PeriodicalIF":6.3,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654260","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 : 2024-11-02DOI: 10.1016/j.polymdegradstab.2024.111070
Hung-Anh Tran Vu , Minh Nguyen Ngoc , Anh Tuan Pham , Viet Huong Nguyen
Polymers are widely used in various industries, however, their sensitivity to environmental factors such as moisture, UV radiation, heat, and some organic solvents limits their application. Atomic layer deposition (ALD) and vapor phase infiltration (VPI) are cutting-edge technologies to enhance the protective performance of polymers. ALD is concerned with depositing uniform, pinhole-free thin films with thickness control down to sub-nanometer level, while VPI creates organic-inorganic hybrid structures, further improving polymer stability. This review aims to evaluate the effectiveness of ALD and VPI for protecting polymers in outdoor applications or advanced technological fields such as lithium-ion batteries (LIBs), organic light-emitting diodes (OLEDs), and biomedical applications. The mechanisms governing ALD and VPI processes on polymers are discussed, alongside with challenges such as deposition on inert polymers, controllability, and scalability. The potential of various metal oxides by ALD/VPI technologies to expand the use of polymers in harsh environments is particularly highlighted, with an emphasis on future research directions and industrial applications.
{"title":"Vapor-phase protective coatings for polymers: Advances and challenges in ALD and VPI technologies","authors":"Hung-Anh Tran Vu , Minh Nguyen Ngoc , Anh Tuan Pham , Viet Huong Nguyen","doi":"10.1016/j.polymdegradstab.2024.111070","DOIUrl":"10.1016/j.polymdegradstab.2024.111070","url":null,"abstract":"<div><div>Polymers are widely used in various industries, however, their sensitivity to environmental factors such as moisture, UV radiation, heat, and some organic solvents limits their application. Atomic layer deposition (ALD) and vapor phase infiltration (VPI) are cutting-edge technologies to enhance the protective performance of polymers. ALD is concerned with depositing uniform, pinhole-free thin films with thickness control down to sub-nanometer level, while VPI creates organic-inorganic hybrid structures, further improving polymer stability. This review aims to evaluate the effectiveness of ALD and VPI for protecting polymers in outdoor applications or advanced technological fields such as lithium-ion batteries (LIBs), organic light-emitting diodes (OLEDs), and biomedical applications. The mechanisms governing ALD and VPI processes on polymers are discussed, alongside with challenges such as deposition on inert polymers, controllability, and scalability. The potential of various metal oxides by ALD/VPI technologies to expand the use of polymers in harsh environments is particularly highlighted, with an emphasis on future research directions and industrial applications.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"230 ","pages":"Article 111070"},"PeriodicalIF":6.3,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654173","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 : 2024-11-02DOI: 10.1016/j.polymdegradstab.2024.111071
Alma Berenice Jasso-Salcedo , Myrna Salinas-Hernández , Abril Fonseca-García , Enrique Javier Jiménez-Regalado , Rocio Yaneli Aguirre-Loredo
Many single–use plastic (SUP) options made of synthetic polymers, bio-based materials, and blends of both are available in the market and used in large quantities. The disintegration of eleven commercial SUP, marketed in Mexico as cups and plates, was investigated in an aerobic home compost environment at a laboratory scale over 180 days. An evaluation of chemical changes, surface morphology, and thermal and mechanical properties was conducted to ascertain the original composition of SUP and the progression of disintegration in samples that are challenging to clean from soil contamination. Furthermore, the impact of residual compost on barley (Hordeum vulgare) plant growth and its correlation with the leaching of heavy metals were explored. The bio-based SUP, but not those made of expanded polystyrene foam, showed a correlation between the disintegration degree (measured by weight loss into particles <2 mm) and a decrease in functional groups (observed by FT-IR), mechanical-thermal stability loss, and surface wear over disintegration time. For instance, the highest disintegration at 180 days was approximately 70 % for wheat bran and palm leaf plates, followed by wheat plates and cellulose-PLA cups (60 %). In addition to the components listed by the manufacturers, the FT-IR and DSC analysis revealed the presence of polyethylene and polypropylene in cellulose cups and sugarcane plates. These components, impede disintegration but contribute to preserving thermal resistance and hydrophobicity during utilization. Compost derived from expanded polystyrene foam SUP, with 90 days of disintegration, was rich in zinc and chromium and significantly decrease in the root length of the barley plant compared to the control. This demonstrates the necessity of considering the impact of the leaching of additives and secondary microplastics into the environment.
{"title":"Disintegration of commercial single-use plastics from synthetic and biobased origins and effects on plant growth","authors":"Alma Berenice Jasso-Salcedo , Myrna Salinas-Hernández , Abril Fonseca-García , Enrique Javier Jiménez-Regalado , Rocio Yaneli Aguirre-Loredo","doi":"10.1016/j.polymdegradstab.2024.111071","DOIUrl":"10.1016/j.polymdegradstab.2024.111071","url":null,"abstract":"<div><div>Many single–use plastic (SUP) options made of synthetic polymers, bio-based materials, and blends of both are available in the market and used in large quantities. The disintegration of eleven commercial SUP, marketed in Mexico as cups and plates, was investigated in an aerobic home compost environment at a laboratory scale over 180 days. An evaluation of chemical changes, surface morphology, and thermal and mechanical properties was conducted to ascertain the original composition of SUP and the progression of disintegration in samples that are challenging to clean from soil contamination. Furthermore, the impact of residual compost on barley (<em>Hordeum vulgare</em>) plant growth and its correlation with the leaching of heavy metals were explored. The bio-based SUP, but not those made of expanded polystyrene foam, showed a correlation between the disintegration degree (measured by weight loss into particles <2 mm) and a decrease in functional groups (observed by FT-IR), mechanical-thermal stability loss, and surface wear over disintegration time. For instance, the highest disintegration at 180 days was approximately 70 % for wheat bran and palm leaf plates, followed by wheat plates and cellulose-PLA cups (60 %). In addition to the components listed by the manufacturers, the FT-IR and DSC analysis revealed the presence of polyethylene and polypropylene in cellulose cups and sugarcane plates. These components, impede disintegration but contribute to preserving thermal resistance and hydrophobicity during utilization. Compost derived from expanded polystyrene foam SUP, with 90 days of disintegration, was rich in zinc and chromium and significantly decrease in the root length of the barley plant compared to the control. This demonstrates the necessity of considering the impact of the leaching of additives and secondary microplastics into the environment.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"230 ","pages":"Article 111071"},"PeriodicalIF":6.3,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654262","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 : 2024-11-01DOI: 10.1016/j.polymdegradstab.2024.111069
Xiao-Hui Shi , Cheng-Yue Jing , Huan Luo , Hong Shi , De-Yi Wang
The effective and eco-friendliness flame retardants for fabrics are increasingly being prioritized. In this study, cotton fabrics were coated with dimethyl phosphite lysine (LP) and phytic acid (PA) to create an eco-friendly and high-efficient fireproof barrier through strong electrostatic attraction and hydrogen bond assembly. The flame-retardant property of the coated cotton fabrics (C/LP10/PA) demonstrated a significant improvement, as evidenced by a limiting oxygen index of 40.2 % and an inherent ability to self-extinguish upon removal of the fire source during vertical burning tests. Furthermore, the synergistic flame-retardant effect of LP and PA resulted in a reduction of 74 % in peak heat release rate and 21 % in total heat release for C/LP10/PA compared to pure cotton. However, the smoke release of C/LP10/PA was increased due to the incomplete combustion. Moreover, the charring process was significantly enhanced in C/LP10/PA with a char residue weight percentage of 26.0 %, from 7.0 % for pure cotton fabric. The analysis of residual char after burning and gaseous products generated during the decomposition process demonstrated that LP/PA coating exhibited flame-retardant properties in both condensed and gas phases. Generally, this work presents a feasible and eco-friendly method for achieving flame retardancy in cotton fabrics.
{"title":"A flame retardant coating based on amino acid and phytic acid for cotton fabrics","authors":"Xiao-Hui Shi , Cheng-Yue Jing , Huan Luo , Hong Shi , De-Yi Wang","doi":"10.1016/j.polymdegradstab.2024.111069","DOIUrl":"10.1016/j.polymdegradstab.2024.111069","url":null,"abstract":"<div><div>The effective and eco-friendliness flame retardants for fabrics are increasingly being prioritized. In this study, cotton fabrics were coated with dimethyl phosphite lysine (LP) and phytic acid (PA) to create an eco-friendly and high-efficient fireproof barrier through strong electrostatic attraction and hydrogen bond assembly. The flame-retardant property of the coated cotton fabrics (C/LP10/PA) demonstrated a significant improvement, as evidenced by a limiting oxygen index of 40.2 % and an inherent ability to self-extinguish upon removal of the fire source during vertical burning tests. Furthermore, the synergistic flame-retardant effect of LP and PA resulted in a reduction of 74 % in peak heat release rate and 21 % in total heat release for C/LP10/PA compared to pure cotton. However, the smoke release of C/LP10/PA was increased due to the incomplete combustion. Moreover, the charring process was significantly enhanced in C/LP10/PA with a char residue weight percentage of 26.0 %, from 7.0 % for pure cotton fabric. The analysis of residual char after burning and gaseous products generated during the decomposition process demonstrated that LP/PA coating exhibited flame-retardant properties in both condensed and gas phases. Generally, this work presents a feasible and eco-friendly method for achieving flame retardancy in cotton fabrics.</div></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":"230 ","pages":"Article 111069"},"PeriodicalIF":6.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142562362","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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