Chirality is one of the most common and significant phenomenon in nature, and epoxy resin is one of the most widely used and researched thermosetting resins, however the influences of chiral carbon in epoxy group on the performances of the cured epoxy resins have ever been hardly studied, therefore it is crucial and meaningful to explore the structure–function relationship of chirality and performance of epoxy resins. Herein, from the analysis of synthesis mechanism, the different chiral configuration with high percent enantiomeric excess (>99%) and racemic bisphenol A epoxy resins were simply prepared by controlling the chirality of epichlorohydrin. The apparent activation energy of the curing process with D230 was calculated by Kissinger method and Flynn–Wall–Ozawa method, respectively, and both results indicate that chirality have no effect on the curing reaction. We found that the secondary structure of epoxy monomer is untouched by its chirality, and they are all right helix structure. For this reason, the thermal stability, glass transition temperature, and thermomechanical properties of diverse chiral epoxy resins cured by D230 have no significant difference. Nevertheless, it was found that the optical rotation activity of chiral epoxy resins can be partially maintained after curing reaction, it manifests the cured products of chiral epoxy resins possesses the possibility of application in the field of polarized materials.
{"title":"Preparation of Chiral Epoxy Resins and the Optically Active Cured Products","authors":"Xinyuan Tang, Ming Hu, Xiaoran Liu, Yanyun Li, Junying Zhang, Jue Cheng","doi":"10.1155/2023/6612220","DOIUrl":"https://doi.org/10.1155/2023/6612220","url":null,"abstract":"Chirality is one of the most common and significant phenomenon in nature, and epoxy resin is one of the most widely used and researched thermosetting resins, however the influences of chiral carbon in epoxy group on the performances of the cured epoxy resins have ever been hardly studied, therefore it is crucial and meaningful to explore the structure–function relationship of chirality and performance of epoxy resins. Herein, from the analysis of synthesis mechanism, the different chiral configuration with high percent enantiomeric excess (>99%) and racemic bisphenol A epoxy resins were simply prepared by controlling the chirality of epichlorohydrin. The apparent activation energy of the curing process with D230 was calculated by Kissinger method and Flynn–Wall–Ozawa method, respectively, and both results indicate that chirality have no effect on the curing reaction. We found that the secondary structure of epoxy monomer is untouched by its chirality, and they are all right helix structure. For this reason, the thermal stability, glass transition temperature, and thermomechanical properties of diverse chiral epoxy resins cured by D230 have no significant difference. Nevertheless, it was found that the optical rotation activity of chiral epoxy resins can be partially maintained after curing reaction, it manifests the cured products of chiral epoxy resins possesses the possibility of application in the field of polarized materials.","PeriodicalId":7372,"journal":{"name":"Advances in Polymer Technology","volume":"468 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135766168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The increasing concerns about solid waste disposal have led to the development of innovative strategies for repurposing waste materials. This paper describes a simple solution casting process for recycling postconsumed footwear leather fiber (PCF) into a biocomposite film reinforced with graphene oxide (GO) and polyvinylpyrrolidone (PVP). PVP was utilized as a compatibilizer to strengthen the interfacial bonding of GO and leather fiber via π–π interactions. UV–visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy were used to examine the material dispersibility bonding between GO and PCF, structural properties, thermal properties, and surface morphology of the biocomposite films, respectively. Compared to pure PCF film, the oxygen transmission rate of the prepared biocomposite films is elevated by 64% as well as the biodegradability rate is intensified up to 60%. In addition, the film’s tensile strengths are raised by 216%, while their elongation at break is increased by 164.64% as compared with PCF. The versatility of these eco-friendly and biodegradable composite films extends to its possible applications in packaging and interior design. The outcomes of the research reveal the viability of manufacturing affordable and sustainable biocomposites through the utilization of waste leather from consumed footwear.
{"title":"Fabrication of Graphene Oxide Reinforced Biocomposite: Recycling of Postconsumed Footwear Leather","authors":"Rashedul Islam, Md Ashikur Rahaman Noyon, Thuhin Kumar Dey, Mamun Jamal, Rajasekar Rathanasamy, Moganapriya Chinnasamy, Md. Elias Uddin","doi":"10.1155/2023/3996687","DOIUrl":"https://doi.org/10.1155/2023/3996687","url":null,"abstract":"The increasing concerns about solid waste disposal have led to the development of innovative strategies for repurposing waste materials. This paper describes a simple solution casting process for recycling postconsumed footwear leather fiber (PCF) into a biocomposite film reinforced with graphene oxide (GO) and polyvinylpyrrolidone (PVP). PVP was utilized as a compatibilizer to strengthen the interfacial bonding of GO and leather fiber via π–π interactions. UV–visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy were used to examine the material dispersibility bonding between GO and PCF, structural properties, thermal properties, and surface morphology of the biocomposite films, respectively. Compared to pure PCF film, the oxygen transmission rate of the prepared biocomposite films is elevated by 64% as well as the biodegradability rate is intensified up to 60%. In addition, the film’s tensile strengths are raised by 216%, while their elongation at break is increased by 164.64% as compared with PCF. The versatility of these eco-friendly and biodegradable composite films extends to its possible applications in packaging and interior design. The outcomes of the research reveal the viability of manufacturing affordable and sustainable biocomposites through the utilization of waste leather from consumed footwear.","PeriodicalId":7372,"journal":{"name":"Advances in Polymer Technology","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135385829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mahmood M. S. Abdullah, Hamad A. Al-Lohedan, Mohd Sajid Ali
Polyethylene terephthalate (PET) is one of the most widely used plastics in the world. Due to the large production and use of this plastic, its waste represents one of the most critical environmental problems. The purpose of this study is to convert PET waste into a valuable material. The consumed PET was transformed into a precursor to synthesize a polyionic liquid (PIL) that was used for dehydrating crude oil emulsions. To do so, the consumed PET was converted to bis(2-hydroxyethyl) terephthalate (BHET). First, BHET and tetraethylene glycol were reacted separately with thionyl chloride, obtaining the corresponding alkyl halides, bis(2-chloroethyl) terephthalate, BCET, and TEC, respectively. Next, the obtained alkyl halides, BCET and TEC, were reacted with 1,5-pentanediamine, yielding a polymer (BTP). Finally, BTP was reacted with acetic acid to produce the corresponding PIL (BTP–PIL). The structure and thermal stability of BTP–PIL were characterized using nuclear magnetic resonance spectroscopy and thermal gravimetric analysis. The dehydration performance of PIL and the original polymer was investigated using the bottle test method, including several factors such as demulsifier dose, brine content, temperature, and settling time. Results indicated that PIL achieved high performance in dehydrating crude oil emulsions.
{"title":"Performance of Plastic Waste-Based Polyionic Liquid toward the Dehydration of Crude Oil Emulsions","authors":"Mahmood M. S. Abdullah, Hamad A. Al-Lohedan, Mohd Sajid Ali","doi":"10.1155/2023/3740956","DOIUrl":"https://doi.org/10.1155/2023/3740956","url":null,"abstract":"Polyethylene terephthalate (PET) is one of the most widely used plastics in the world. Due to the large production and use of this plastic, its waste represents one of the most critical environmental problems. The purpose of this study is to convert PET waste into a valuable material. The consumed PET was transformed into a precursor to synthesize a polyionic liquid (PIL) that was used for dehydrating crude oil emulsions. To do so, the consumed PET was converted to bis(2-hydroxyethyl) terephthalate (BHET). First, BHET and tetraethylene glycol were reacted separately with thionyl chloride, obtaining the corresponding alkyl halides, bis(2-chloroethyl) terephthalate, BCET, and TEC, respectively. Next, the obtained alkyl halides, BCET and TEC, were reacted with 1,5-pentanediamine, yielding a polymer (BTP). Finally, BTP was reacted with acetic acid to produce the corresponding PIL (BTP–PIL). The structure and thermal stability of BTP–PIL were characterized using nuclear magnetic resonance spectroscopy and thermal gravimetric analysis. The dehydration performance of PIL and the original polymer was investigated using the bottle test method, including several factors such as demulsifier dose, brine content, temperature, and settling time. Results indicated that PIL achieved high performance in dehydrating crude oil emulsions.","PeriodicalId":7372,"journal":{"name":"Advances in Polymer Technology","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134885101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Omar Faruk, Yang Yang, Jiangliang Zhang, Junxin Yu, Jiaojiao Lv, Weichao Lv, Yueying Du, Jindan Wu, Dongming Qi
Ultrahigh molecular weight polyethylene (UHMWPE) fiber is widely recognized for its exceptional properties, including high strength-to-weight ratio, toughness, and chemical resistance, making it a preferred material for reinforcement in various applications. However, its low melting point, surface inertness, and weak adhesion to polymer matrices have limited its potential use in some fields. Researchers have addressed these shortcomings by focusing on surface modifications through physical treatment or chemical coating, thereby enhancing the versatility of materials in numerous UHMWPE fiber composites. By improving the tribological and interfacial properties of UHMWPE, various applications can be explored, including prosthetic joints, energy-absorbing road safety systems, microelectromechanical system devices, and protective materials for defense and personal thermal management. This review provides a comprehensive overview of the remarkable performance of UHMWPE and its composites, providing insights into its wide array of applications.
{"title":"A Comprehensive Review of Ultrahigh Molecular Weight Polyethylene Fibers for Applications Based on Their Different Preparation Techniques","authors":"Omar Faruk, Yang Yang, Jiangliang Zhang, Junxin Yu, Jiaojiao Lv, Weichao Lv, Yueying Du, Jindan Wu, Dongming Qi","doi":"10.1155/2023/6656692","DOIUrl":"https://doi.org/10.1155/2023/6656692","url":null,"abstract":"Ultrahigh molecular weight polyethylene (UHMWPE) fiber is widely recognized for its exceptional properties, including high strength-to-weight ratio, toughness, and chemical resistance, making it a preferred material for reinforcement in various applications. However, its low melting point, surface inertness, and weak adhesion to polymer matrices have limited its potential use in some fields. Researchers have addressed these shortcomings by focusing on surface modifications through physical treatment or chemical coating, thereby enhancing the versatility of materials in numerous UHMWPE fiber composites. By improving the tribological and interfacial properties of UHMWPE, various applications can be explored, including prosthetic joints, energy-absorbing road safety systems, microelectromechanical system devices, and protective materials for defense and personal thermal management. This review provides a comprehensive overview of the remarkable performance of UHMWPE and its composites, providing insights into its wide array of applications.","PeriodicalId":7372,"journal":{"name":"Advances in Polymer Technology","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135063340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hananeh Hamedfar, Tayebeh Zivari-Ghader, A. Akbarzadeh, S. Davaran
In addition to being a lipid-lowering medication, atorvastatin (ATV) is an anti-inflammatory agent. When there is a bone defect or inflammation of adjacent tissues, it aids in bone repair. This study aimed to develop a chitosan–alginate (CS/ALG)–tripolyphosphate (TPP)–ATV hybrid hydrogel as a drug delivery system, using a tissue engineering scaffold for the first time. For this purpose, a CS/ALG hydrogel crosslinked with TPP was developed. The delivery profile of ATV and its physicochemical properties such as particle size and hydrogel swelling percentage were determined. The structure and morphology of the hydrogels were analyzed using Fourier transform infrared spectroscopy and scanning electron microscopy. As a result, an alginate–chitosan hydrogel with a TPP crosslinker was prepared. The results revealed that drug loading was nearly complete, and the first hour revealed a 25% explosive release. The drug was gradually released over 10 hr at approximately 35%. The amount of crosslinker used significantly influenced the encapsulation gain and release profiles. Owing to its high porosity and swelling, the CS/ALG hydrogel crosslinked with PPT is an ideal scaffold for loading drugs, macromolecules, and cells.
{"title":"Physicochemical Characteristics of Chitosan–Alginate Scaffold Containing Atorvastatin","authors":"Hananeh Hamedfar, Tayebeh Zivari-Ghader, A. Akbarzadeh, S. Davaran","doi":"10.1155/2023/9452164","DOIUrl":"https://doi.org/10.1155/2023/9452164","url":null,"abstract":"In addition to being a lipid-lowering medication, atorvastatin (ATV) is an anti-inflammatory agent. When there is a bone defect or inflammation of adjacent tissues, it aids in bone repair. This study aimed to develop a chitosan–alginate (CS/ALG)–tripolyphosphate (TPP)–ATV hybrid hydrogel as a drug delivery system, using a tissue engineering scaffold for the first time. For this purpose, a CS/ALG hydrogel crosslinked with TPP was developed. The delivery profile of ATV and its physicochemical properties such as particle size and hydrogel swelling percentage were determined. The structure and morphology of the hydrogels were analyzed using Fourier transform infrared spectroscopy and scanning electron microscopy. As a result, an alginate–chitosan hydrogel with a TPP crosslinker was prepared. The results revealed that drug loading was nearly complete, and the first hour revealed a 25% explosive release. The drug was gradually released over 10 hr at approximately 35%. The amount of crosslinker used significantly influenced the encapsulation gain and release profiles. Owing to its high porosity and swelling, the CS/ALG hydrogel crosslinked with PPT is an ideal scaffold for loading drugs, macromolecules, and cells.","PeriodicalId":7372,"journal":{"name":"Advances in Polymer Technology","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49078186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lion Sundermann, Sebastian Leineweber, B. Klie, Heike Wittek, T. Ebel, B. Reitz, Kathrin Ottink, Matthias Graf, Tobias Lankenau, L. Overmeyer, U. Giese
The additive manufacturing (AM) of elastomeric parts based on high-viscosity reinforced rubbers has increasingly become a topic of scientific research in recent years. In addition to the viscosity, which is several decades higher during processing than the viscosities of thermoplastics, the flowability of the compound after the printing process and the necessary chemical crosslinking of the printed component play a decisive role in producing an elastic, high-quality, and geometrically stable part. After the first technological achievements using the so-called additive manufacturing of elastomers (AME) process, the knowledge gained has to be transferred first to concrete industrial parts. Therefore, in this study, the cure kinetics of a conventional rubber compound are tailored to match the specific requirements for scorch safety in the additive manufacturing of an industrial 2-component rod seal based on an acrylonitrile butadiene rubber O-ring in combination with a thermoplastic polyurethane as the base body. Experimental tests on a test rig for rod seals demonstrate the functionality of this additively manufactured 2-component rod seal.
{"title":"Tailoring the Curing Kinetics of NBR-Based Rubber Compounds for Additive Manufacturing of Rod Seals","authors":"Lion Sundermann, Sebastian Leineweber, B. Klie, Heike Wittek, T. Ebel, B. Reitz, Kathrin Ottink, Matthias Graf, Tobias Lankenau, L. Overmeyer, U. Giese","doi":"10.1155/2023/7343194","DOIUrl":"https://doi.org/10.1155/2023/7343194","url":null,"abstract":"The additive manufacturing (AM) of elastomeric parts based on high-viscosity reinforced rubbers has increasingly become a topic of scientific research in recent years. In addition to the viscosity, which is several decades higher during processing than the viscosities of thermoplastics, the flowability of the compound after the printing process and the necessary chemical crosslinking of the printed component play a decisive role in producing an elastic, high-quality, and geometrically stable part. After the first technological achievements using the so-called additive manufacturing of elastomers (AME) process, the knowledge gained has to be transferred first to concrete industrial parts. Therefore, in this study, the cure kinetics of a conventional rubber compound are tailored to match the specific requirements for scorch safety in the additive manufacturing of an industrial 2-component rod seal based on an acrylonitrile butadiene rubber O-ring in combination with a thermoplastic polyurethane as the base body. Experimental tests on a test rig for rod seals demonstrate the functionality of this additively manufactured 2-component rod seal.","PeriodicalId":7372,"journal":{"name":"Advances in Polymer Technology","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2023-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44489409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Vivek, C. Aravind, S. Gokulkumar, M. Aravindh, Yalew Asres
Ultra-high-performance fibre-reinforced concrete (UHPFRC) is a specialized type of concrete (to create a very dense matrix) that is used for both new construction and renovation projects in order to improve the lifespan of structures. Researchers analyse and evaluate only the microstructure, porosity, and fresh and hardened concrete properties of UHPFRC but limited their exploration on the reduction of the mechanical properties of UHPFRC due to the presence of metallic particles and micro-fractures that occur during the generation of hydrogen. Hence, the present study aims to eliminate the existing problem by hybridization approach (mixing of bio-nano-silica (nS) and polypropylene) with different percentages to further improve the strength properties of UHPFRC. The result showed that the compressive strength is increased by 15.5% compared to traditional concrete due to the filling ratio of nS in the pores of the concrete; in addition, the fibre’s surface and roughness also contributed to the strength enhancement.
{"title":"Fabrication and Characterization of Partial Bio-nano-silica Inclusion in Fibre-Reinforced Concrete for High-performance Applications","authors":"D. Vivek, C. Aravind, S. Gokulkumar, M. Aravindh, Yalew Asres","doi":"10.1155/2023/4379941","DOIUrl":"https://doi.org/10.1155/2023/4379941","url":null,"abstract":"Ultra-high-performance fibre-reinforced concrete (UHPFRC) is a specialized type of concrete (to create a very dense matrix) that is used for both new construction and renovation projects in order to improve the lifespan of structures. Researchers analyse and evaluate only the microstructure, porosity, and fresh and hardened concrete properties of UHPFRC but limited their exploration on the reduction of the mechanical properties of UHPFRC due to the presence of metallic particles and micro-fractures that occur during the generation of hydrogen. Hence, the present study aims to eliminate the existing problem by hybridization approach (mixing of bio-nano-silica (nS) and polypropylene) with different percentages to further improve the strength properties of UHPFRC. The result showed that the compressive strength is increased by 15.5% compared to traditional concrete due to the filling ratio of nS in the pores of the concrete; in addition, the fibre’s surface and roughness also contributed to the strength enhancement.","PeriodicalId":7372,"journal":{"name":"Advances in Polymer Technology","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2023-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46452582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Venkatesh, P. S. Santhosh Kumar, A. Senthilkumar, J. P. Krishna, P. Chandramohan, V. Aneesh, Avinash Malladi, C. Priya, Elangomathavan Ramaraj
Polymer matrix composites synthesized with biodegradable natural fiber obtain a predominant structure with specific properties at a low-processing cost. The unique characteristics of polymer matrix composites were magnetized in automotive parts like top roof, panel, and seat frame applications. American Society for Testing and Materials (ASTM) G99 analyzed the wear characteristics of synthesized composites through a pin-on-disc wear tester with an EN32 steel disc. The epoxy hybrid composites have been synthesized via a conventional casting process assisted with a mechanical interlock technique to obtain a predominant structure with specific properties at a low-processing cost. The advanced composite contained different jute weights (50, 25, 50, and 75 g) and coconut coir (50, 70, 45, and 20 g) hybridized with graphite particles. ASTM D2240, D638, and D790 standards evaluated the fabricated composite hardness, tensile, and flexural strength. The Sample 4 hybrid composite found maximum hardness, tensile, and flexural strength of 27.41 ± 0.99 Hv, 51.69 ± 1.01MPa, and 55.94 ± 0.78 MPa, respectively. Sample 4 offered good wear resistance of their volumetric wear rate of 0.043 cm3 on 40 N average load at 0.25 m/s sliding speed. It is increased by 12% compared to Sample 1 at 40 N applied load on 2.5 m/s sliding speed.
{"title":"Mechanical Interlocking Approaches to the Prediction of Mechanical and Tribological Behavior of Natural Fiber-Reinforced Polymer Hybrid Nanocomposites or Automotive Applications","authors":"R. Venkatesh, P. S. Santhosh Kumar, A. Senthilkumar, J. P. Krishna, P. Chandramohan, V. Aneesh, Avinash Malladi, C. Priya, Elangomathavan Ramaraj","doi":"10.1155/2023/6685060","DOIUrl":"https://doi.org/10.1155/2023/6685060","url":null,"abstract":"Polymer matrix composites synthesized with biodegradable natural fiber obtain a predominant structure with specific properties at a low-processing cost. The unique characteristics of polymer matrix composites were magnetized in automotive parts like top roof, panel, and seat frame applications. American Society for Testing and Materials (ASTM) G99 analyzed the wear characteristics of synthesized composites through a pin-on-disc wear tester with an EN32 steel disc. The epoxy hybrid composites have been synthesized via a conventional casting process assisted with a mechanical interlock technique to obtain a predominant structure with specific properties at a low-processing cost. The advanced composite contained different jute weights (50, 25, 50, and 75 g) and coconut coir (50, 70, 45, and 20 g) hybridized with graphite particles. ASTM D2240, D638, and D790 standards evaluated the fabricated composite hardness, tensile, and flexural strength. The Sample 4 hybrid composite found maximum hardness, tensile, and flexural strength of 27.41 ± 0.99 Hv, 51.69 ± 1.01MPa, and 55.94 ± 0.78 MPa, respectively. Sample 4 offered good wear resistance of their volumetric wear rate of 0.043 cm3 on 40 N average load at 0.25 m/s sliding speed. It is increased by 12% compared to Sample 1 at 40 N applied load on 2.5 m/s sliding speed.","PeriodicalId":7372,"journal":{"name":"Advances in Polymer Technology","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2023-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45897263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Benzoxazine (BZ)-epoxy copolymers exhibit favorable mechanical properties, but their thermal and flame-retardant characteristics are impaired at high epoxy fractions. Here, we report a new type of sulfur-containing epoxy resin (EPS), which we synthesized using 4,4’-thiobisphenol (TBP) instead of bisphenol A (BA) and then blended with three sulfur-containing BZs (TBP-a, TBP-fa, and TBP-tma). The polymerization behavior of the resins was analyzed using Fourier transform infrared spectroscopy and differential scanning calorimetry for determining the optimal curing procedure. This analysis revealed that the oxazine and epoxy rings undergo ring-opening and cross-linking reactions at the same time and that double-substituted structures originating from the furan and thiophene rings appeared during the curing process. Thermogravimetric analysis showed that the addition of EPS increased the initial decomposition temperature by hindering the formation of double-substituted structures. The char yield at 800°C decreased owing to the unstable C–O–C–C–O groups derived from the ring-opening of EPS. To prepare the self-extinguishing copolymers with a char yield of 24%, a smaller quantity of BZ was needed for the EPS-based blends than for the BA-based ones. The heat release capacities—measured using micro-combustion calorimetry—of all copolymers except TBP-a/EPS were less than 300 J/g·K, demonstrating that the presence of thioether bonds and double-substituted structures resulted in excellent flame retardancy. The TBP-fa/EPS copolymer also exhibited excellent flame retardancy in cone calorimeter measurement. Finally, the glass transition temperature of the TBP-fa/EPS copolymer at a ratio of 5 : 5 (w/w) reached as high as 289°C. A TBP-fa/EPS copolymer with an epoxy content of 70% had nearly the same storage modulus (2,206 MPa) at 50°C as poly(BA-a) and thus similar mechanical properties. In summary, BZ-epoxy copolymers prepared from sulfur-containing epoxy combine the advantages of the constituent components and extend their areas of application.
{"title":"Intrinsically Noncombustible Thermosets from Sulfur-Containing Epoxy Resin and Benzoxazines: Evaluation of Thermal and Mechanical Properties","authors":"Yanchen Lyu, Haibo Fan, L. Qiu","doi":"10.1155/2023/1686001","DOIUrl":"https://doi.org/10.1155/2023/1686001","url":null,"abstract":"Benzoxazine (BZ)-epoxy copolymers exhibit favorable mechanical properties, but their thermal and flame-retardant characteristics are impaired at high epoxy fractions. Here, we report a new type of sulfur-containing epoxy resin (EPS), which we synthesized using 4,4’-thiobisphenol (TBP) instead of bisphenol A (BA) and then blended with three sulfur-containing BZs (TBP-a, TBP-fa, and TBP-tma). The polymerization behavior of the resins was analyzed using Fourier transform infrared spectroscopy and differential scanning calorimetry for determining the optimal curing procedure. This analysis revealed that the oxazine and epoxy rings undergo ring-opening and cross-linking reactions at the same time and that double-substituted structures originating from the furan and thiophene rings appeared during the curing process. Thermogravimetric analysis showed that the addition of EPS increased the initial decomposition temperature by hindering the formation of double-substituted structures. The char yield at 800°C decreased owing to the unstable C–O–C–C–O groups derived from the ring-opening of EPS. To prepare the self-extinguishing copolymers with a char yield of 24%, a smaller quantity of BZ was needed for the EPS-based blends than for the BA-based ones. The heat release capacities—measured using micro-combustion calorimetry—of all copolymers except TBP-a/EPS were less than 300 J/g·K, demonstrating that the presence of thioether bonds and double-substituted structures resulted in excellent flame retardancy. The TBP-fa/EPS copolymer also exhibited excellent flame retardancy in cone calorimeter measurement. Finally, the glass transition temperature of the TBP-fa/EPS copolymer at a ratio of 5 : 5 (w/w) reached as high as 289°C. A TBP-fa/EPS copolymer with an epoxy content of 70% had nearly the same storage modulus (2,206 MPa) at 50°C as poly(BA-a) and thus similar mechanical properties. In summary, BZ-epoxy copolymers prepared from sulfur-containing epoxy combine the advantages of the constituent components and extend their areas of application.","PeriodicalId":7372,"journal":{"name":"Advances in Polymer Technology","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2023-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46177684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Biopolymer-based catalysts like chitosan, chitin, and cellulose offer sustainability and high efficiency both as the catalyst or catalyst support in a broad range of applications, especially in hydrogen evolution reactions. This review focused on hydrogen evolution catalysts of chitosan, chitin, cellulose, and carbon materials obtained from these biopolymers to highlight the opportunities of these sustainable catalysts in this field. All the reports in this area could be classified as one of the photocatalysts, electrocatalysts, and photoelectrocatalysts, and their mechanisms were clarified in the beginning. Then, the results of catalysts obtained from each of these biopolymers were discussed separately to reveal the roles of the biopolymers. It was concluded that all of the biopolymers enjoy some common benefits like hydrogen bonding, chelating with transition metals, easy chemical modification, high performance, and potential to be used as the precursors of carbon or porous materials. Among them, chitosan showed outstanding merit due to the better performance in metal grafting, amendment, and ability of hydrogen bonding. Moreover, it provides highly active nitrogen-doped carbon as the support of transition metals in the hydrogen generation, enhancing the reaction rate by retarding the charges recombination.
{"title":"A Review on Hydrogen Generation by Photo-, Electro-, and Photoelectro-Catalysts Based on Chitosan, Chitin, Cellulose, and Carbon Materials Obtained from These Biopolymers","authors":"S. Keshipour, Mina Hadidi, Ozra Gholipour","doi":"10.1155/2023/8835940","DOIUrl":"https://doi.org/10.1155/2023/8835940","url":null,"abstract":"Biopolymer-based catalysts like chitosan, chitin, and cellulose offer sustainability and high efficiency both as the catalyst or catalyst support in a broad range of applications, especially in hydrogen evolution reactions. This review focused on hydrogen evolution catalysts of chitosan, chitin, cellulose, and carbon materials obtained from these biopolymers to highlight the opportunities of these sustainable catalysts in this field. All the reports in this area could be classified as one of the photocatalysts, electrocatalysts, and photoelectrocatalysts, and their mechanisms were clarified in the beginning. Then, the results of catalysts obtained from each of these biopolymers were discussed separately to reveal the roles of the biopolymers. It was concluded that all of the biopolymers enjoy some common benefits like hydrogen bonding, chelating with transition metals, easy chemical modification, high performance, and potential to be used as the precursors of carbon or porous materials. Among them, chitosan showed outstanding merit due to the better performance in metal grafting, amendment, and ability of hydrogen bonding. Moreover, it provides highly active nitrogen-doped carbon as the support of transition metals in the hydrogen generation, enhancing the reaction rate by retarding the charges recombination.","PeriodicalId":7372,"journal":{"name":"Advances in Polymer Technology","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43399643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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