Journal of Vinyl and Additive Technology最新文献_第2页

Use of modifiers ZSM‐5 and bentonite enhancing the hydrolytic and thermal stability of urea‐formaldehyde composites 使用改性剂 ZSM-5 和膨润土提高脲醛复合材料的水解稳定性和热稳定性

Journal of Vinyl and Additive Technology Pub Date : 2024-08-22 DOI: 10.1002/vnl.22153

Mirjana Ristić, Suzana Samaržija‐Jovanović, Marija Krstić, Tijana Jovanović, Vojislav Jovanović, Gordana Marković, Milena Marinović‐Cincović

{"title":"Use of modifiers ZSM‐5 and bentonite enhancing the hydrolytic and thermal stability of urea‐formaldehyde composites","authors":"Mirjana Ristić, Suzana Samaržija‐Jovanović, Marija Krstić, Tijana Jovanović, Vojislav Jovanović, Gordana Marković, Milena Marinović‐Cincović","doi":"10.1002/vnl.22153","DOIUrl":"https://doi.org/10.1002/vnl.22153","url":null,"abstract":"This research introduces a new approach using zeolite ZSM‐5 (Z) as formaldehyde (FA) scavenger in urea‐formaldehyde (UF) resins, while simultaneously investigating and comparing the structural influence of Z and bentonite (B) on different properties of UF composite. ZSM‐5 and bentonite were used to modify the in situ synthesized UF resin with a low formaldehyde/urea (FA/U) molar ratio (0.8), to reduce the free FA content in the UF resin. The fillers and modified UF composites were characterized using XRD, FTIR, TGA, DTG, and DTA. The surface of fillers and modified UF resins was observed using SEM. The content of free FA, determined by the sulfite method, for the sample UF/Z composite, was 0.06%, while for the sample UF/B composite was 0.18%. After acid hydrolysis, the content of released FA was similar for both modified resins (4.08% for UF/Z and 4.80% for UF/B). This slight difference indicates a better hydrolytic stability of UF/Z. Analysis of thermal stability showed that UF/Z starts to degrade at a higher temperature, which, together with the values of released FA, indicates that UF resin modified with ZSM‐5 is thermally and hydrolytically more stable compared to the UF/B composite. The obtained results suggest that ZSM‐5 with its microporous structure contributes better to improving the properties of UF resins than bentonite with its layered structure.Highlights Synthesis of UF resins modified with ZSM‐5 and bentonite. New approach using ZSM‐5 as a formaldehyde scavenger. Comprehensive characterization of the fillers and modified UF resins. UF/Z resin has superior hydrolytic and thermal stability over UF/B resin. The microporous structure of ZSM‐5 enhances the properties of UF. ","PeriodicalId":17473,"journal":{"name":"Journal of Vinyl and Additive Technology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142216056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of melt‐processing conditions on the electrical conductivity and microwave absorbing properties of composites based on clean scrap poly(vinylidene fluoride/ethylene vinyl acetate copolymer and graphene nanoplatelets 熔融加工条件对基于清洁废料聚偏氟乙烯/醋酸乙烯共聚物和石墨烯纳米颗粒的复合材料的导电性和微波吸收特性的影响

Journal of Vinyl and Additive Technology Pub Date : 2024-08-21 DOI: 10.1002/vnl.22156

Debora P. Schmitz, Beatriz S. Cunha, Bluma G. Soares

{"title":"Effect of melt‐processing conditions on the electrical conductivity and microwave absorbing properties of composites based on clean scrap poly(vinylidene fluoride/ethylene vinyl acetate copolymer and graphene nanoplatelets","authors":"Debora P. Schmitz, Beatriz S. Cunha, Bluma G. Soares","doi":"10.1002/vnl.22156","DOIUrl":"https://doi.org/10.1002/vnl.22156","url":null,"abstract":"Clean scrap polyvinylidene fluoride (rPVDF) from industrial reject was compounded with ethylene vinyl acetate (EVA) copolymer and graphene nanoplatelets (GNP) to produce low cost and scalable conductive composites. The effect of the melt processing conditions (temperature, time, and rotor speed) on the electrical conductivity and microwave absorbing (MWA) properties was investigated. All systems presented co‐continuous morphology indicated by scanning electron microscopy (SEM) and selective extraction experiments. The preferential localization of GNP in the EVA phase was evidenced by selective extraction and thermogravimetric analysis (TGA). Higher conductivity value was observed for the composite processed at 210°C for 3 min at a rotor speed of 200 rpm. The MWA performance of monolayer and bilayer composite structures with 2 mm thickness was investigated in terms of minimum reflection loss (RL) and effective absorption bandwidth (EAB). The bilayer system provided the best MWA response with RL = − 43.1 dB (>99.99% of EM attenuation) when prepared at 190°C for 3 min at a rotor speed of 200 rpm. The ecological and environmental importance of finding new applications for plastic waste, and the low cost of the materials and processing make this composite an interesting candidate for MWA purpose.Highlights Promising application of clean scrap polyvinylidene fluoride (PVDF) in microwave absorbing materials; Conductivity and absorbing performance are affected by processing conditions; Co‐continuous structure of rPVDF/EVA blend influenced by graphene nanoplatelets (GNP); Selective localization of GNP in EVA phase; Outstanding microwave absorption properties achieved with bi‐layer structure. ","PeriodicalId":17473,"journal":{"name":"Journal of Vinyl and Additive Technology","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142216058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Sulfated cellulose nanocrystal isolated from waste cotton fabrics by deep eutectic solvent and its application in polymer nanocomposite films 利用深共晶溶剂从废棉织物中分离出硫酸化纤维素纳米晶及其在聚合物纳米复合薄膜中的应用

Journal of Vinyl and Additive Technology Pub Date : 2024-08-18 DOI: 10.1002/vnl.22154

Lebin Zhao, Yutong Zhang, Yu Pan, Chaohong Dong, Xiujuan Huang, Gangqiang Zhang, Kaitao Zhang

{"title":"Sulfated cellulose nanocrystal isolated from waste cotton fabrics by deep eutectic solvent and its application in polymer nanocomposite films","authors":"Lebin Zhao, Yutong Zhang, Yu Pan, Chaohong Dong, Xiujuan Huang, Gangqiang Zhang, Kaitao Zhang","doi":"10.1002/vnl.22154","DOIUrl":"https://doi.org/10.1002/vnl.22154","url":null,"abstract":"The growing utilization of textiles raises concerns about the ecological hazards of textile production methods and discarded textiles. The recycling and reusing of waste cotton materials align with the sustainable development of society. In this study, sulfated cellulose was synthesized by sulfating waste cotton using a deep eutectic solvent (DES). After nanofibrillation with ultrasonication, sulfated cellulose nanocrystal (SCNC) with an average width of 10.83 nm and an average length of 129.40 nm was produced. The thermal properties of the synthesized SCNC were significantly enhanced compared to the pristine cellulose, with a notable reduction of 87.1% in the peak heat release rate, as well as an 86.6% reduction in the total heat release. Additionally, when utilized as a reinforcement in poly(vinyl alcohol) (PVA) films, SCNC demonstrated a substantial rise in yield strength (from 62.3 to 94.8 MPa) and Young's modulus (from 2.7 to 4.4 GPa) of the PVA films. Furthermore, the incorporation of SCNC into composites increased the thermal stability while maintaining the high transparency (with light transmission higher than 84%), which has good potential for application in the electronic packaging field.Highlights SCNC were successfully prepared from waste cotton using DES. Extracted SCNC were characterized using TEM, FTIR, XRD, TGA and MCC. SCNC enhanced the yield strength and thermal stability of PVA composites. Transparent and mechanically robust PVA‐based nanocomposites were created. ","PeriodicalId":17473,"journal":{"name":"Journal of Vinyl and Additive Technology","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142216073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exploring the tribological impact of micaceous additives in copper‐free automobile brake friction composites 探索无铜汽车制动摩擦复合材料中微粒添加剂对摩擦学的影响

Journal of Vinyl and Additive Technology Pub Date : 2024-07-17 DOI: 10.1002/vnl.22142

G. Sathyamoorthy, Vijay Raghunathan, Sanjay Mavinkere Rangappa, Suchart Siengchin, D. Lenin Singaravelu

{"title":"Exploring the tribological impact of micaceous additives in copper‐free automobile brake friction composites","authors":"G. Sathyamoorthy, Vijay Raghunathan, Sanjay Mavinkere Rangappa, Suchart Siengchin, D. Lenin Singaravelu","doi":"10.1002/vnl.22142","DOIUrl":"https://doi.org/10.1002/vnl.22142","url":null,"abstract":"This study investigates the tribological impact of incorporating micaceous additives in copper‐free brake friction composites for automotive applications. Four brake pad formulations were created, each containing different amounts of muscovite and phlogopite, ranging from 0% to 10% by weight. A brake pad comparison was conducted by replacing mica with synthetic barites. The physical, thermal, mechanical, and chemical properties of the fabricated brake friction composite were examined. Tribological features were evaluated through inertia brake dynamometer testing following the JASO‐C‐406 schedule. Scanning electron microscope (SEM) analysis delved into contact plateau formations and back transfer patches on the brake pad's surfaces. Notably, phlogopite‐based pads exhibited enhanced thermal stability and efficient heat dissipation, contributing to sustained tribological performance. Overall, the comprehensive evaluation using the multiple objective optimization by ratio analysis (MOORA) method positioned phlogopite‐based brake pads as the optimal choice for optimized braking performances.Highlights Exploration of micaceous additives as an ingredient in brake friction composite. Phlogopite‐based brake pads showed better fade and recovery performance. Phlogopite‐based brake pads exhibited low pad wear and rotor wear. MOORA optimization positioned phlogopite‐based brake pads as the optimal choice. ","PeriodicalId":17473,"journal":{"name":"Journal of Vinyl and Additive Technology","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141742625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0