Pub Date : 2022-10-19DOI: 10.1177/00952443221130475
Jagesh Kumar Ranjan, S. Goswami
Interpenetrating polymer networks based on vinyl ester resin and polyurethane were synthesized using different blend ratio, for example, 93:7, 90:10, and 80:20 (w/w). The samples were subjected to thermogravimetric analysis under non-isothermal conditions in presence of an inert atmosphere within the temperature range of 303–773K. Determination of distributed activation energy at various stages of degradation process and its implication in the reaction mechanism was investigated by using various isoconversional models and Kissinger’s model fitting approaches. It was observed that IPNs showed higher thermal stability and also possessed higher activation energy for degradation than pure VE in the selected range of temperature when heated at a specific rate.
{"title":"Studies on the thermal stability of vinyl ester/polyurethane IPNs by gravimetric analysis","authors":"Jagesh Kumar Ranjan, S. Goswami","doi":"10.1177/00952443221130475","DOIUrl":"https://doi.org/10.1177/00952443221130475","url":null,"abstract":"Interpenetrating polymer networks based on vinyl ester resin and polyurethane were synthesized using different blend ratio, for example, 93:7, 90:10, and 80:20 (w/w). The samples were subjected to thermogravimetric analysis under non-isothermal conditions in presence of an inert atmosphere within the temperature range of 303–773K. Determination of distributed activation energy at various stages of degradation process and its implication in the reaction mechanism was investigated by using various isoconversional models and Kissinger’s model fitting approaches. It was observed that IPNs showed higher thermal stability and also possessed higher activation energy for degradation than pure VE in the selected range of temperature when heated at a specific rate.","PeriodicalId":15613,"journal":{"name":"Journal of Elastomers & Plastics","volume":"10 1","pages":"1148 - 1171"},"PeriodicalIF":0.0,"publicationDate":"2022-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83150686","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}
Pub Date : 2022-10-17DOI: 10.1177/00952443221133240
N. Syed, Utkarsh Utkarsh, Muhammad Tariq, A. Behravesh, Qingping Guo, G. Rizvi, R. Pop-Iliev
Despite being inexpensive and robust, steel cord reinforcements are often prone to pose risks to user health and safety in some industrial applications such as escalator handrails and rubber conveyor belts. Steel cords can reduce the overall stability and performance of the application over time due to their inherent creep accompanied by cyclic thermal expansion and contraction. In this context, this research focuses on replacing steel cords in some critical thermoplastic polyurethane (TPU) composite applications with continuous sustainable alternate synthetic fibers that possess high specific strength (e.g. carbon, glass, and Kevlar fibers). The first part of this research characterizes the effect of epoxy coating on synthetic fibers alone by studying their mechanical properties before and after modification, whereas the second half of the research involves reinforcing a TPU matrix with raw and epoxy-coated synthetic fibers to fabricate fiber-reinforced composites by compression molding. The effect of the curing temperature of epoxy on the end performance of the manufactured specimen was also tested. An in-depth analysis of mechanical and morphological studies showed that, at almost the same volume fraction of fibers, the TPU reinforced composites with modified carbon fibers showed higher load-bearing capacities than steel cord-based analogs. Conversely, a wide variety of other relevant industrial and commercial applications can potentially draw significant benefits by implementing these modified carbon/TPU composites instead of steel cords.
{"title":"Experimental evaluation of utilizing synthetic continuous fiber reinforcements for thermoplastics as an alternative to steel-based analogs","authors":"N. Syed, Utkarsh Utkarsh, Muhammad Tariq, A. Behravesh, Qingping Guo, G. Rizvi, R. Pop-Iliev","doi":"10.1177/00952443221133240","DOIUrl":"https://doi.org/10.1177/00952443221133240","url":null,"abstract":"Despite being inexpensive and robust, steel cord reinforcements are often prone to pose risks to user health and safety in some industrial applications such as escalator handrails and rubber conveyor belts. Steel cords can reduce the overall stability and performance of the application over time due to their inherent creep accompanied by cyclic thermal expansion and contraction. In this context, this research focuses on replacing steel cords in some critical thermoplastic polyurethane (TPU) composite applications with continuous sustainable alternate synthetic fibers that possess high specific strength (e.g. carbon, glass, and Kevlar fibers). The first part of this research characterizes the effect of epoxy coating on synthetic fibers alone by studying their mechanical properties before and after modification, whereas the second half of the research involves reinforcing a TPU matrix with raw and epoxy-coated synthetic fibers to fabricate fiber-reinforced composites by compression molding. The effect of the curing temperature of epoxy on the end performance of the manufactured specimen was also tested. An in-depth analysis of mechanical and morphological studies showed that, at almost the same volume fraction of fibers, the TPU reinforced composites with modified carbon fibers showed higher load-bearing capacities than steel cord-based analogs. Conversely, a wide variety of other relevant industrial and commercial applications can potentially draw significant benefits by implementing these modified carbon/TPU composites instead of steel cords.","PeriodicalId":15613,"journal":{"name":"Journal of Elastomers & Plastics","volume":"9 1","pages":"1221 - 1237"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85705683","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}
Pub Date : 2022-10-11DOI: 10.1177/00952443221133539
Tao Wu, Wu-gao Zhang, Haiyong Peng, Haibo Zhang
The compatibility of elastomers used in engine fuel system with Fischer–Tropsch (FT) fuel is essential, but there is very limited research available on it. In this work, the compatibility between four types of commonly used elastomers in fuel system and FT fuel was experimentally investigated. The assessed elastomers including nitrile butadiene rubber (NBR), ethylene propylene diene-monomer rubber (EPDM), fluoroelastomer (FKM), and chlorinated polyethylene (CPE) were exposed to FT fuel which derived from natural gas for 21 days. The properties of the elastomers such as mass, volume, hardness, tensile strength, elongation at break, and tear strength were measured before and after immersion, at the same time the change rates of these properties were calculated. The results demonstrated that all properties of EPDM deteriorated significantly after soak, and its compatibility with FT fuel was the worst, making it unsuitable for FT engines. NBR, FKM, and CPE all showed low rates of property change, with FKM exhibiting the greatest compatibility performance with FT fuel. Additionally, the O-rings made of FKM were submerged in FT fuel and diesel for 7 days, 14 days, and 21 days, respectively. It was found that the mass and volume variations of FKM O-rings in FT fuel were negligible and comparable with those of diesel fuel.
{"title":"Study on volume swell and mechanical properties of fuel system elastomers with Fischer–Tropsch fuel for diesel engines","authors":"Tao Wu, Wu-gao Zhang, Haiyong Peng, Haibo Zhang","doi":"10.1177/00952443221133539","DOIUrl":"https://doi.org/10.1177/00952443221133539","url":null,"abstract":"The compatibility of elastomers used in engine fuel system with Fischer–Tropsch (FT) fuel is essential, but there is very limited research available on it. In this work, the compatibility between four types of commonly used elastomers in fuel system and FT fuel was experimentally investigated. The assessed elastomers including nitrile butadiene rubber (NBR), ethylene propylene diene-monomer rubber (EPDM), fluoroelastomer (FKM), and chlorinated polyethylene (CPE) were exposed to FT fuel which derived from natural gas for 21 days. The properties of the elastomers such as mass, volume, hardness, tensile strength, elongation at break, and tear strength were measured before and after immersion, at the same time the change rates of these properties were calculated. The results demonstrated that all properties of EPDM deteriorated significantly after soak, and its compatibility with FT fuel was the worst, making it unsuitable for FT engines. NBR, FKM, and CPE all showed low rates of property change, with FKM exhibiting the greatest compatibility performance with FT fuel. Additionally, the O-rings made of FKM were submerged in FT fuel and diesel for 7 days, 14 days, and 21 days, respectively. It was found that the mass and volume variations of FKM O-rings in FT fuel were negligible and comparable with those of diesel fuel.","PeriodicalId":15613,"journal":{"name":"Journal of Elastomers & Plastics","volume":"2014 1","pages":"1202 - 1218"},"PeriodicalIF":0.0,"publicationDate":"2022-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86827906","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}
Pub Date : 2022-10-10DOI: 10.1177/00952443221133237
M. Vadivel, S. Jayakumar, B. B. Lahiri, J. Philip
Nano-mechanical properties of silicone polymer-based nanocomposites loaded with multi-walled carbon nanotube (MWCNT) as nanofillers are probed here using the atomic force microscopy (AFM) technique. Further, the effects of MWCNT concentration and X-ray exposure on the nano-mechanical and topographic properties of the polymer nanocomposites are systematically studied. The root mean square surface roughness is found to increase by ∼123% when the neat polymer matrix is loaded with 2.5 wt.% of MWCNT, whereas, for a fixed MWCNT concentration, the surface roughness is found to increase by ∼171% after X-ray irradiation. This is attributed to the X-ray induced polymer degradation, polymer pull-out and poor filler-matrix interaction leading to the aggregation of MWCNT. Adhesion force and adhesion energy are estimated from the AFM-based force-displacement curves. Both quantities are found to increase with MWCNT concentration. After an exposure to diagnostic X-rays (30–70 keV), the adhesion force is found to increase by ∼4 times, which is attributed to the increased tip-surface contact area due to the higher surface roughness of the X-ray exposed samples. Further, the variation of adhesion energy with filler concentration is found to be in agreement with the theoretical values obtained from the Johnson, Kendall and Roberts (JKR) model. The elastic modulus is found to increase with the filler concentration due to an increase in adhesion force. The obtained results are beneficial for the optimal design of nanofiller loaded polymer nanocomposites for various applications, including the fabrication of lead-free radio-opaque nanocomposites.
{"title":"Effect of X-ray exposure on nano-mechanical properties of multi-walled carbon nanotube incorporated silicone polymer nanocomposites: An AFM-based study","authors":"M. Vadivel, S. Jayakumar, B. B. Lahiri, J. Philip","doi":"10.1177/00952443221133237","DOIUrl":"https://doi.org/10.1177/00952443221133237","url":null,"abstract":"Nano-mechanical properties of silicone polymer-based nanocomposites loaded with multi-walled carbon nanotube (MWCNT) as nanofillers are probed here using the atomic force microscopy (AFM) technique. Further, the effects of MWCNT concentration and X-ray exposure on the nano-mechanical and topographic properties of the polymer nanocomposites are systematically studied. The root mean square surface roughness is found to increase by ∼123% when the neat polymer matrix is loaded with 2.5 wt.% of MWCNT, whereas, for a fixed MWCNT concentration, the surface roughness is found to increase by ∼171% after X-ray irradiation. This is attributed to the X-ray induced polymer degradation, polymer pull-out and poor filler-matrix interaction leading to the aggregation of MWCNT. Adhesion force and adhesion energy are estimated from the AFM-based force-displacement curves. Both quantities are found to increase with MWCNT concentration. After an exposure to diagnostic X-rays (30–70 keV), the adhesion force is found to increase by ∼4 times, which is attributed to the increased tip-surface contact area due to the higher surface roughness of the X-ray exposed samples. Further, the variation of adhesion energy with filler concentration is found to be in agreement with the theoretical values obtained from the Johnson, Kendall and Roberts (JKR) model. The elastic modulus is found to increase with the filler concentration due to an increase in adhesion force. The obtained results are beneficial for the optimal design of nanofiller loaded polymer nanocomposites for various applications, including the fabrication of lead-free radio-opaque nanocomposites.","PeriodicalId":15613,"journal":{"name":"Journal of Elastomers & Plastics","volume":"88 1","pages":"1172 - 1201"},"PeriodicalIF":0.0,"publicationDate":"2022-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76854281","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}
Pub Date : 2022-10-01DOI: 10.1177/00952443221131197
R. Sritharan, D. Askari
Epoxy is one of the widely used polymeric resin systems in composite industries, which is a two-part resin system that requires the mixing of a hardening agent to trigger the polymerization process. The mixing ratio and pot-life are usually specified and provided by the manufacturer; however, the stirring time and the details of the mixing process were left to the fabricator to configure, based on some visual observations, which may vary from person to person. Although the mixing ratio is fixed by the resin manufacturer, errors may occur during the weighing and transfer of resin parts. The hardener concentration and stirring time are two of the most important factors that can affect the resin properties. In addition, air bubbles can be formed during the stirring process, which is inevitable. Design of experiment (DOE) is one of the widely used tools to design, control, and study the effects of multiple factors. In this research, DOE with a factorial design of 23−1 (2k−1) was used to study the effects of hardener concentration, stirring time, and air bubbles on the tensile strength of epoxy resin. Test specimens were fabricated, cut, and tested as per ASTM D638 standard (i.e., common test performed in the industry for plastics) in a randomized order and then the results were statistically analyzed using Design-Expert software. The test results showed that all three factors significantly affect the tensile strength of the epoxy, and they should be carefully optimized and used for the fabrication of composite materials with optimal properties.
{"title":"A design of experiment study to investigate the effects of hardener concentration, stirring time, and air bubbles on the tensile strength of epoxy resin","authors":"R. Sritharan, D. Askari","doi":"10.1177/00952443221131197","DOIUrl":"https://doi.org/10.1177/00952443221131197","url":null,"abstract":"Epoxy is one of the widely used polymeric resin systems in composite industries, which is a two-part resin system that requires the mixing of a hardening agent to trigger the polymerization process. The mixing ratio and pot-life are usually specified and provided by the manufacturer; however, the stirring time and the details of the mixing process were left to the fabricator to configure, based on some visual observations, which may vary from person to person. Although the mixing ratio is fixed by the resin manufacturer, errors may occur during the weighing and transfer of resin parts. The hardener concentration and stirring time are two of the most important factors that can affect the resin properties. In addition, air bubbles can be formed during the stirring process, which is inevitable. Design of experiment (DOE) is one of the widely used tools to design, control, and study the effects of multiple factors. In this research, DOE with a factorial design of 23−1 (2k−1) was used to study the effects of hardener concentration, stirring time, and air bubbles on the tensile strength of epoxy resin. Test specimens were fabricated, cut, and tested as per ASTM D638 standard (i.e., common test performed in the industry for plastics) in a randomized order and then the results were statistically analyzed using Design-Expert software. The test results showed that all three factors significantly affect the tensile strength of the epoxy, and they should be carefully optimized and used for the fabrication of composite materials with optimal properties.","PeriodicalId":15613,"journal":{"name":"Journal of Elastomers & Plastics","volume":"329 1","pages":"1129 - 1147"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76863987","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}
Pub Date : 2022-10-01DOI: 10.1177/00952443221107358
Elham Badakhshanian, M. Ghaemy
This study prepared a type of bio-based elastomeric polyurethane from tragacanth gum (TG). TG is a natural polysaccharide with many hydroxyl groups that can be used as a chain extender and a crosslinker to react with the isocyanate groups in polyurethane prepolymer to form a highly branched and crosslinked polyurethane with high molecular weight and good mechanical properties. The chemical structure of the prepolymer and the thermal and mechanical properties of the prepared polyurethane were studied by Fourier transform infrared, nuclear magnetic resonance, scanning electron microscopy, thermal gravimetric analysis, dynamic mechanical thermal analysis, and tensile strength tester. The properties of the polyurethane-based on TG (TG-PU) were compared with the properties of the PU based on only polyethylene glycol. The TG-PU sample with 0.5 g TG showed a tensile strength of 288% and the glass transition temperature (Tg) of 33% higher than the tensile strength and Tg of PU without TG. We expect these findings to widen the range of preparation and applications of bio-based polyurethane materials. Graphical Abstract
本研究以黄棘胶为原料制备了一种生物基弹性聚氨酯。TG是一种具有许多羟基的天然多糖,可作为扩链剂和交联剂与聚氨酯预聚物中的异氰酸酯基团反应,形成高支链交联的聚氨酯,具有高分子量和良好的力学性能。采用傅里叶变换红外、核磁共振、扫描电镜、热重分析、动态力学热分析和拉伸强度测试仪等对预聚物的化学结构和制备的聚氨酯的热力学性能进行了研究。比较了TG基聚氨酯(TG-PU)与纯聚乙二醇基聚氨酯的性能。添加0.5 g TG的TG-PU试样的抗拉强度和玻璃化转变温度(TG)比未添加TG的PU试样的抗拉强度和TG分别提高了288%和33%。我们期望这些发现能拓宽生物基聚氨酯材料的制备和应用范围。图形抽象
{"title":"Synthesis, characterization, and properties of a new polyurethane elastomer based on tragacanth gum polysaccharide","authors":"Elham Badakhshanian, M. Ghaemy","doi":"10.1177/00952443221107358","DOIUrl":"https://doi.org/10.1177/00952443221107358","url":null,"abstract":"This study prepared a type of bio-based elastomeric polyurethane from tragacanth gum (TG). TG is a natural polysaccharide with many hydroxyl groups that can be used as a chain extender and a crosslinker to react with the isocyanate groups in polyurethane prepolymer to form a highly branched and crosslinked polyurethane with high molecular weight and good mechanical properties. The chemical structure of the prepolymer and the thermal and mechanical properties of the prepared polyurethane were studied by Fourier transform infrared, nuclear magnetic resonance, scanning electron microscopy, thermal gravimetric analysis, dynamic mechanical thermal analysis, and tensile strength tester. The properties of the polyurethane-based on TG (TG-PU) were compared with the properties of the PU based on only polyethylene glycol. The TG-PU sample with 0.5 g TG showed a tensile strength of 288% and the glass transition temperature (Tg) of 33% higher than the tensile strength and Tg of PU without TG. We expect these findings to widen the range of preparation and applications of bio-based polyurethane materials. Graphical Abstract","PeriodicalId":15613,"journal":{"name":"Journal of Elastomers & Plastics","volume":"1 1","pages":"1025 - 1039"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82350635","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}
Pub Date : 2022-09-30DOI: 10.1177/00952443221131199
Atif Mahmood, S. Alam
Silicone rubber-based polymers are gradually replacing traditional insulators in outdoor applications due to their numerous advantages, in particular high hydrophobicity that is important for suppressing leakage current and hence surface flashover. However, the main problem with polymeric composites is their aging when exposed to environmental stresses causing loss of their desired properties and expected lifetime. In this work, aging behavior of three types of room temperature vulcanized silicon rubber (RTV-SiR) loaded with nano-silica and micro-ATH is studied. Samples of the materials with different specifications were fabricated and exposed to various environmental stresses in two specially designed weather chambers under both AC and bipolar DC voltages for a time period of 9000 hours. Thereafter, diagnosis was performed for identifying the degree of deterioration using several techniques. These include hydrophobicity classification, measurements of leakage current and mechanical properties, Fourier transform infrared spectroscopy, and Thermogravimetric analysis. Results of the conducted experiments indicated stronger degradation of the desired properties under positive DC stress as compared to the AC and negative DC voltages. Moreover, silicone rubber doped with nano-sized particles of silica filler demonstrated better anti-aging performance as compared to its micro-ATH filled counterpart.
{"title":"RTV-SiR based composites aged in a multi-stressed environment under AC and bipolar DC voltages","authors":"Atif Mahmood, S. Alam","doi":"10.1177/00952443221131199","DOIUrl":"https://doi.org/10.1177/00952443221131199","url":null,"abstract":"Silicone rubber-based polymers are gradually replacing traditional insulators in outdoor applications due to their numerous advantages, in particular high hydrophobicity that is important for suppressing leakage current and hence surface flashover. However, the main problem with polymeric composites is their aging when exposed to environmental stresses causing loss of their desired properties and expected lifetime. In this work, aging behavior of three types of room temperature vulcanized silicon rubber (RTV-SiR) loaded with nano-silica and micro-ATH is studied. Samples of the materials with different specifications were fabricated and exposed to various environmental stresses in two specially designed weather chambers under both AC and bipolar DC voltages for a time period of 9000 hours. Thereafter, diagnosis was performed for identifying the degree of deterioration using several techniques. These include hydrophobicity classification, measurements of leakage current and mechanical properties, Fourier transform infrared spectroscopy, and Thermogravimetric analysis. Results of the conducted experiments indicated stronger degradation of the desired properties under positive DC stress as compared to the AC and negative DC voltages. Moreover, silicone rubber doped with nano-sized particles of silica filler demonstrated better anti-aging performance as compared to its micro-ATH filled counterpart.","PeriodicalId":15613,"journal":{"name":"Journal of Elastomers & Plastics","volume":"70 1","pages":"1091 - 1111"},"PeriodicalIF":0.0,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86395729","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}
Pub Date : 2022-09-27DOI: 10.1177/00952443221130471
Yao Qin, Xiao-Ya Yuan, Z. Sang, Zhiyuan Zhang, Jing‐bo Zhao, Junying Zhang
A simple non-isocyanate route is established to synthesize biobased aliphatic thermoplastic polyurethane elastomers (TPEUs) with excellent mechanical properties. Melt transurethane co-polycondensation of bis(hydroxyethyl) butanediurethane (BHBDU) with different polycaprolactone-diols (PCDLs) was conducted at 170°C under a reduced pressure of 3 mmHg, and a series of TPEUs were prepared. The TPEUs were characterized by gel permeation chromatography, FT-IR, 1H-NMR, wide angle X-ray scattering, DSC, TGA, dynamic mechanical analysis, atomic force microscopy, and tensile test. TPUEs exhibited Mn above 25,000 g/mol, Tg of −36 to 1°C, Tm up to 105°C, maximal tensile strength of 38 MPa with a strain at break of 926%, and resilience of 80%–90%. BHBDU and PCDLs may be synthesized from bioresources. Biobased aliphatic TPU elastomers with excellent tensile strength and resilience were prepared successfully through a non-isocyanate route.
{"title":"Synthesis and properties of biobased non-isocyanate aliphatic thermoplastic polyurethane elastomers with butanediurethane hard segments","authors":"Yao Qin, Xiao-Ya Yuan, Z. Sang, Zhiyuan Zhang, Jing‐bo Zhao, Junying Zhang","doi":"10.1177/00952443221130471","DOIUrl":"https://doi.org/10.1177/00952443221130471","url":null,"abstract":"A simple non-isocyanate route is established to synthesize biobased aliphatic thermoplastic polyurethane elastomers (TPEUs) with excellent mechanical properties. Melt transurethane co-polycondensation of bis(hydroxyethyl) butanediurethane (BHBDU) with different polycaprolactone-diols (PCDLs) was conducted at 170°C under a reduced pressure of 3 mmHg, and a series of TPEUs were prepared. The TPEUs were characterized by gel permeation chromatography, FT-IR, 1H-NMR, wide angle X-ray scattering, DSC, TGA, dynamic mechanical analysis, atomic force microscopy, and tensile test. TPUEs exhibited Mn above 25,000 g/mol, Tg of −36 to 1°C, Tm up to 105°C, maximal tensile strength of 38 MPa with a strain at break of 926%, and resilience of 80%–90%. BHBDU and PCDLs may be synthesized from bioresources. Biobased aliphatic TPU elastomers with excellent tensile strength and resilience were prepared successfully through a non-isocyanate route.","PeriodicalId":15613,"journal":{"name":"Journal of Elastomers & Plastics","volume":"28 1","pages":"1112 - 1128"},"PeriodicalIF":0.0,"publicationDate":"2022-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82798953","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}
Pub Date : 2022-08-08DOI: 10.1177/00952443221118636
Md Najib Alam, S. Debnath, O. Boondamnoen, K. N. Kumar, J. Kim, Jungwook Choi
In this study, we developed a combination accelerator system to synergistically improve the vulcanizing activity of 2-marcapto benzothiazole (MBT) with different nitrosamine-safe thiuram disulfides (TDs), namely, bis-(N-benzyl piperazino) thiuram disulfide (BPTD), bis-(N-phenyl piperazino) thiuram disulfide (PPTD), and bis-(N-ethyl piperazino) thiuram disulfide (EPTD), which can be used as nitrosamine-safe cross-linking accelerators for sulfur based rubber vulcanization. The results were compared with that of a conventionally unsafe TD, tetramethyl thiuram disulfide (TMTD) combined with MBT, to evaluate the efficiencies of these nitrosamine-safe TD accelerators for industrial applications. The curing and mechanical properties of rubber vulcanization were investigated to understand the synergism between MBT and nitrosoamine-safe TDs. The results indicate that novel TDs combined with MBT significantly improve the curing characteristics and mechanical properties following to the TDs with smaller molecular size and higher basicity. The MBT/BPTD system had higher modulus values because BPTD has a higher molar mass, which facilitates a better distribution of accelerators in the rubber matrix. Overall, the MBT/EPTD accelerator systems with equal molar ratios can compete with the curing rates, tensile strengths, and moduli of unsafe TMTD accelerator systems in the vulcanization of rubber.
{"title":"Synergistic combination of 2-mercaptobenzothiazole (MBT) and nitrosoamine-safe thiuram disulfide as advanced rubber vulcanizing accelerators","authors":"Md Najib Alam, S. Debnath, O. Boondamnoen, K. N. Kumar, J. Kim, Jungwook Choi","doi":"10.1177/00952443221118636","DOIUrl":"https://doi.org/10.1177/00952443221118636","url":null,"abstract":"In this study, we developed a combination accelerator system to synergistically improve the vulcanizing activity of 2-marcapto benzothiazole (MBT) with different nitrosamine-safe thiuram disulfides (TDs), namely, bis-(N-benzyl piperazino) thiuram disulfide (BPTD), bis-(N-phenyl piperazino) thiuram disulfide (PPTD), and bis-(N-ethyl piperazino) thiuram disulfide (EPTD), which can be used as nitrosamine-safe cross-linking accelerators for sulfur based rubber vulcanization. The results were compared with that of a conventionally unsafe TD, tetramethyl thiuram disulfide (TMTD) combined with MBT, to evaluate the efficiencies of these nitrosamine-safe TD accelerators for industrial applications. The curing and mechanical properties of rubber vulcanization were investigated to understand the synergism between MBT and nitrosoamine-safe TDs. The results indicate that novel TDs combined with MBT significantly improve the curing characteristics and mechanical properties following to the TDs with smaller molecular size and higher basicity. The MBT/BPTD system had higher modulus values because BPTD has a higher molar mass, which facilitates a better distribution of accelerators in the rubber matrix. Overall, the MBT/EPTD accelerator systems with equal molar ratios can compete with the curing rates, tensile strengths, and moduli of unsafe TMTD accelerator systems in the vulcanization of rubber.","PeriodicalId":15613,"journal":{"name":"Journal of Elastomers & Plastics","volume":"45 1","pages":"1061 - 1077"},"PeriodicalIF":0.0,"publicationDate":"2022-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85788294","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}
Pub Date : 2022-07-19DOI: 10.1177/00952443221089048
Tuba Ünügül, Metin Erenkaya, B. Karaağaç
Phenolic resins are useful additives that provide various functions for rubber compounds during compounding and vulcanization, as well as after cure. Natural resins are considered as strong alternatives to synthetic ones due to environmental concern. Liquidambar Orientalis Mills is an endemic plant and grows in many different geographies including Turkey. In this study, the phenolic resin obtained from Liquidambar Orientalis Mills has been studied regarding its functions in a generic natural rubber compound. It was incorporated into the rubber compound with and without selected gum and phenolic resins so that mainly obtaining competitive adhesion properties. Both individual and collaborative effects of the natural resin were evaluated. Rheological, thermal, morphological, mechanical and adhesion properties of the compounds were studied comparatively along with the non-linear cure kinetics. Liquidambar Orientalis Mills has been found to be a good alternative to both gum and phenolic resins in rubber compounds. Besides, significant improvement could be achieved for particularly rubber–steel adhesion.
酚醛树脂是一种有用的添加剂,在橡胶化合物的合成和硫化过程中以及固化后提供各种功能。由于对环境的关注,天然树脂被认为是合成树脂的有力替代品。Liquidambar Orientalis Mills是一种地方性植物,生长在许多不同的地区,包括土耳其。本文研究了从东方木中提取的酚醛树脂在一种通用天然橡胶中的功能。将其掺入胶料和不掺入胶料和酚醛树脂的胶料中,主要获得竞争性粘附性能。评估了天然树脂的单独效应和协同效应。通过非线性固化动力学,比较研究了化合物的流变、热、形态、力学和粘附性能。在橡胶化合物中,洋柳胶是胶和酚醛树脂的良好替代品。此外,橡胶-钢的附着力也有明显改善。
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