Jinbo Liu, Xue-zhi Tang, Xiaotong Chen, Guoqing Wang
Abstract The study of repairing materials is of paramount importance, considering that damage during usage can significantly impact performance and bring inconvenience during maintenance work. One highly sought-after material is water-swellable elastomers, known for their effect in sealing and repairing damaged materials. In this study, agar/polyurethane dual-network hydrogel elastomers were prepared, which were further modified by MXene. The material exhibits a uniform and flat surface, along with a rich pore-filled internal structure. It showcases excellent thermal stability, good tensile strength retention, and a controllable low swelling rate (SR) upon water absorption. The performance of the material can be regulated by the MXene content. In addition, the “water absorption–drying–water absorption” cycle effectively controls the reduction of the SR and gradually increases the tensile strength. All samples demonstrated exceptional photothermal conversion efficiency, stability, and durability, with the maximum conversion temperature increasing with the MXene content. The scratch repair experiments demonstrated the remarkable potential of these materials for photothermal conversion-assisted repair. These materials can be adapted as auxiliary restoration materials in water bodies and various application environments, making them ideal for repair and restoration purposes.
{"title":"Investigation of MXene-modified agar/polyurethane hydrogel elastomeric repair materials with tunable water absorption","authors":"Jinbo Liu, Xue-zhi Tang, Xiaotong Chen, Guoqing Wang","doi":"10.1515/epoly-2023-0035","DOIUrl":"https://doi.org/10.1515/epoly-2023-0035","url":null,"abstract":"Abstract The study of repairing materials is of paramount importance, considering that damage during usage can significantly impact performance and bring inconvenience during maintenance work. One highly sought-after material is water-swellable elastomers, known for their effect in sealing and repairing damaged materials. In this study, agar/polyurethane dual-network hydrogel elastomers were prepared, which were further modified by MXene. The material exhibits a uniform and flat surface, along with a rich pore-filled internal structure. It showcases excellent thermal stability, good tensile strength retention, and a controllable low swelling rate (SR) upon water absorption. The performance of the material can be regulated by the MXene content. In addition, the “water absorption–drying–water absorption” cycle effectively controls the reduction of the SR and gradually increases the tensile strength. All samples demonstrated exceptional photothermal conversion efficiency, stability, and durability, with the maximum conversion temperature increasing with the MXene content. The scratch repair experiments demonstrated the remarkable potential of these materials for photothermal conversion-assisted repair. These materials can be adapted as auxiliary restoration materials in water bodies and various application environments, making them ideal for repair and restoration purposes.","PeriodicalId":11806,"journal":{"name":"e-Polymers","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46236802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Polyvinyl alcohol (PVA) hydrogels have been extensively investigated for drug release, artificial cartilage, biosensing, and other applications owing to their good chemical stability, biocompatibility, high water absorption, and ease of processing. However, the conventional hydrogel preparation method is complex and energy-intensive, and the mechanical performance of the pure PVA hydrogel is poor, which severely limits its application in related fields. In this study, a PVA hydrogel was functionally modified using polybutylene succinate (PBS) nanofibers prepared using in situ fiber-forming technology to fabricate a PBS-enhanced PVA composite hydrogel. The strength of the PBS/PVA hydrogel fabricated in this study is 3.88 MPa, which is 4.94 times that of the pure PVA hydrogel; thus, the strength of the hydrogel was effectively improved. The hydrogel preparation method used in this study is novel and straightforward. Moreover, the resulting materials are biodegradable and non-toxic. Compared to conventional methods, this method has the advantages of conserving resources and being environmentally friendly.
{"title":"Fiber-reinforced polyvinyl alcohol hydrogel via in situ fiber formation","authors":"Zheng Guo, Zebo Wang, Wei-Ying Pan, Jintao Zhang, Yu Qi, Yajie Qin, Yi Zhang","doi":"10.1515/epoly-2023-0056","DOIUrl":"https://doi.org/10.1515/epoly-2023-0056","url":null,"abstract":"Abstract Polyvinyl alcohol (PVA) hydrogels have been extensively investigated for drug release, artificial cartilage, biosensing, and other applications owing to their good chemical stability, biocompatibility, high water absorption, and ease of processing. However, the conventional hydrogel preparation method is complex and energy-intensive, and the mechanical performance of the pure PVA hydrogel is poor, which severely limits its application in related fields. In this study, a PVA hydrogel was functionally modified using polybutylene succinate (PBS) nanofibers prepared using in situ fiber-forming technology to fabricate a PBS-enhanced PVA composite hydrogel. The strength of the PBS/PVA hydrogel fabricated in this study is 3.88 MPa, which is 4.94 times that of the pure PVA hydrogel; thus, the strength of the hydrogel was effectively improved. The hydrogel preparation method used in this study is novel and straightforward. Moreover, the resulting materials are biodegradable and non-toxic. Compared to conventional methods, this method has the advantages of conserving resources and being environmentally friendly.","PeriodicalId":11806,"journal":{"name":"e-Polymers","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46912075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Heat stabilizers are crucial additives for enhancing the thermal stability of polyvinyl chloride (PVC) during processing. Among the various heat stabilizers available, organic tin compounds have shown remarkable effectiveness. In this study, we investigated the use of dimethyltin dineodecanoate (DMTDN), dibutyltin dineodecanoate (DBTDN), and dioctyltin dineodecanoate (DOTDN) as heat stabilizers for PVC. These compounds were combined with calcium stearate (CaSt2) and zinc stearate (ZnSt2) to improve the thermal stability of PVC materials. The results demonstrated that the thermal stabilization effects of the three tin neodecanoates, when used as standalone heat stabilizers, followed the order: DOTDN > DBTDN > DMTDN. Notably, the thermal stability and lubricity of the three-component heat stabilizer (MTN5-C4Z1, BTN5-C4Z1, and OTN5-C4Z1, respectively), which consisted of the three types of tin neodecanoate, CaSt2, and ZnSt2 in a ratio of 5:4:1, outperformed the use of tin neodecanoate alone. This study offered potential formulations to reduce the application cost of tin neodecanoate as a PVC heat stabilizer.
{"title":"Effect of different tin neodecanoate and calcium–zinc heat stabilizers on the thermal stability of PVC","authors":"Xiang Wang, Chao Di, Tingwei Wang","doi":"10.1515/epoly-2023-0029","DOIUrl":"https://doi.org/10.1515/epoly-2023-0029","url":null,"abstract":"Abstract Heat stabilizers are crucial additives for enhancing the thermal stability of polyvinyl chloride (PVC) during processing. Among the various heat stabilizers available, organic tin compounds have shown remarkable effectiveness. In this study, we investigated the use of dimethyltin dineodecanoate (DMTDN), dibutyltin dineodecanoate (DBTDN), and dioctyltin dineodecanoate (DOTDN) as heat stabilizers for PVC. These compounds were combined with calcium stearate (CaSt2) and zinc stearate (ZnSt2) to improve the thermal stability of PVC materials. The results demonstrated that the thermal stabilization effects of the three tin neodecanoates, when used as standalone heat stabilizers, followed the order: DOTDN > DBTDN > DMTDN. Notably, the thermal stability and lubricity of the three-component heat stabilizer (MTN5-C4Z1, BTN5-C4Z1, and OTN5-C4Z1, respectively), which consisted of the three types of tin neodecanoate, CaSt2, and ZnSt2 in a ratio of 5:4:1, outperformed the use of tin neodecanoate alone. This study offered potential formulations to reduce the application cost of tin neodecanoate as a PVC heat stabilizer.","PeriodicalId":11806,"journal":{"name":"e-Polymers","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48893475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Felix Sahayaraj Arockiasamy, Mayakrishnan Muthukrishnan, Jenish Iyyadurai, Seeniappan Kaliappan, Natrayan Lakshmaiya, Sinouvassane Djearamane, Lai-Hock Tey, Ling Shing Wong, Saminathan Kayarohanam, Sami Al Obaid, Saleh Alfarraj, Subpiramaniyam Sivakumar
Abstract The tribological properties of the sponge gourd outer skin fiber (SGOSF)-reinforced epoxy composites filled with tamarind seed powder were investigated using a pin-on-disc dry sliding wear testing machine. The fiber and filler contents were kept constant (30 and 7.5 wt%). The fibers were treated with sodium hydroxide (NaOH), which increases the bonding strength that has been identified by scanning electron microscope (SEM). A filler content of 7.5 wt% has better hardness due to the embedment of filler with treated fiber and epoxy. Therefore, the SGOSFs/epoxy with 7.5 wt% tamarind filler was chosen for the study of tribological characterization. The lowest specific wear rate of 2.565 × 10 −4 mm 3 ·N m −1 was obtained using the design of expert optimization technique for the control factors such as a load of 44.99 N, a sliding distance of 1,701.39 m, and a sliding velocity of 3.36 m·s −1 using a ramp plot at the desirable level of 1. For the gripping material application, the highest coefficient of friction value of 0.51 was obtained by maintaining the specified input parameters, such as a load of 42.15 N, a sliding distance of 1,874.86 m, and a sliding velocity of 4.99 m·s −1 using a ramp plot at the desirable level of 0.927. SEM images were used to investigate the failure mechanism of the worn surfaces, which substantiates the failure of the pure matrix layer on the surface even at low load, followed by the formation of a rarely breakable adhesive layer.
{"title":"Tribological characterization of sponge gourd outer skin fiber-reinforced epoxy composite with <i>Tamarindus indica</i> seed filler addition using the Box–Behnken method","authors":"Felix Sahayaraj Arockiasamy, Mayakrishnan Muthukrishnan, Jenish Iyyadurai, Seeniappan Kaliappan, Natrayan Lakshmaiya, Sinouvassane Djearamane, Lai-Hock Tey, Ling Shing Wong, Saminathan Kayarohanam, Sami Al Obaid, Saleh Alfarraj, Subpiramaniyam Sivakumar","doi":"10.1515/epoly-2023-0052","DOIUrl":"https://doi.org/10.1515/epoly-2023-0052","url":null,"abstract":"Abstract The tribological properties of the sponge gourd outer skin fiber (SGOSF)-reinforced epoxy composites filled with tamarind seed powder were investigated using a pin-on-disc dry sliding wear testing machine. The fiber and filler contents were kept constant (30 and 7.5 wt%). The fibers were treated with sodium hydroxide (NaOH), which increases the bonding strength that has been identified by scanning electron microscope (SEM). A filler content of 7.5 wt% has better hardness due to the embedment of filler with treated fiber and epoxy. Therefore, the SGOSFs/epoxy with 7.5 wt% tamarind filler was chosen for the study of tribological characterization. The lowest specific wear rate of 2.565 × 10 −4 mm 3 ·N m −1 was obtained using the design of expert optimization technique for the control factors such as a load of 44.99 N, a sliding distance of 1,701.39 m, and a sliding velocity of 3.36 m·s −1 using a ramp plot at the desirable level of 1. For the gripping material application, the highest coefficient of friction value of 0.51 was obtained by maintaining the specified input parameters, such as a load of 42.15 N, a sliding distance of 1,874.86 m, and a sliding velocity of 4.99 m·s −1 using a ramp plot at the desirable level of 0.927. SEM images were used to investigate the failure mechanism of the worn surfaces, which substantiates the failure of the pure matrix layer on the surface even at low load, followed by the formation of a rarely breakable adhesive layer.","PeriodicalId":11806,"journal":{"name":"e-Polymers","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135662687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiaan Liu, Sijian Lu, Xinjing Liu, Bo Wang, Zerun Yu, Chaojie Che
Abstract In this study, Indocalamus micro/nanofibers (IMFs) were extracted from natural Indocalamus leaves by physical processing and alkaline treatment. IMFs reinforced epoxy resin (EP) and their carbon-fiber composites (IMFs/CFRP) were fabricated. The effects of IMF on the mechanical properties of the EP and CFRP composites were studied. Infrared spectroscopy and scanning electron microscopy (SEM) were used to characterize the functional groups and microstructure of IMF, EP, and CFRP. The experimental results showed that the strength of the EP increased as the IMF content increased from 0% to 20%, but on further increase in IMF content of 25%, the strength of the EP reduced. In addition, the mechanical properties of the IMF/CFRP were slightly higher as compared with the control CFRP. The SEM observations on IMFs/EP and IMFs/CFRP composites reveal that the alkali-treated IMFs facilitate the interfacial interlocking structure and improve the interfacial adhesion of the composites.
{"title":"Effect of natural <i>Indocalamus</i> leaf addition on the mechanical properties of epoxy and epoxy-carbon fiber composites","authors":"Jiaan Liu, Sijian Lu, Xinjing Liu, Bo Wang, Zerun Yu, Chaojie Che","doi":"10.1515/epoly-2023-0039","DOIUrl":"https://doi.org/10.1515/epoly-2023-0039","url":null,"abstract":"Abstract In this study, Indocalamus micro/nanofibers (IMFs) were extracted from natural Indocalamus leaves by physical processing and alkaline treatment. IMFs reinforced epoxy resin (EP) and their carbon-fiber composites (IMFs/CFRP) were fabricated. The effects of IMF on the mechanical properties of the EP and CFRP composites were studied. Infrared spectroscopy and scanning electron microscopy (SEM) were used to characterize the functional groups and microstructure of IMF, EP, and CFRP. The experimental results showed that the strength of the EP increased as the IMF content increased from 0% to 20%, but on further increase in IMF content of 25%, the strength of the EP reduced. In addition, the mechanical properties of the IMF/CFRP were slightly higher as compared with the control CFRP. The SEM observations on IMFs/EP and IMFs/CFRP composites reveal that the alkali-treated IMFs facilitate the interfacial interlocking structure and improve the interfacial adhesion of the composites.","PeriodicalId":11806,"journal":{"name":"e-Polymers","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135650059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xuya Fu, Tao Zhang, Wenshuo Zhang, Yuye Zhong, Shuliang Fang, Guannan Wang, Y. Li, Yajun Deng, Xinghai Liu, Houbin Li
Abstract Biomass films with ultraviolet (UV)-shielding ability have attracted considerable attention. Curcumin was introduced into castor oil-based polyurethane (CCPU) as a chain extender, which was melt with polylactic acid (PLA) as a reinforcement to obtain biomass UV-shielding film. The excellent UV absorption and antioxidant qualities of curcumin contributed to the impressive UV-shielding capacity (97.6% UV radiation absorption) and antioxidant (51% free radical scavenging) of PLA/CCPU-20 film. In the scanning electron microscopic images of film fracture, the mixing of CCPU elastomer into the PLA matrix caused the blend films to exhibit significant toughening fracture characteristics compared to the pure PLA film. The excellent thermal stability, low water swelling degree, and low water solubility of PLA/CCPU blend films were maintained after CCPU was added to the PLA matrix. Therefore, the PLA/CCPU blend films can be considered as a potential packaging material because of its favorable UV-shielding properties and film stability. Graphical abstract Schematic for the preparation of the PLA/CCPU blend films.
{"title":"Melt-blended PLA/curcumin-cross-linked polyurethane film for enhanced UV-shielding ability","authors":"Xuya Fu, Tao Zhang, Wenshuo Zhang, Yuye Zhong, Shuliang Fang, Guannan Wang, Y. Li, Yajun Deng, Xinghai Liu, Houbin Li","doi":"10.1515/epoly-2023-0009","DOIUrl":"https://doi.org/10.1515/epoly-2023-0009","url":null,"abstract":"Abstract Biomass films with ultraviolet (UV)-shielding ability have attracted considerable attention. Curcumin was introduced into castor oil-based polyurethane (CCPU) as a chain extender, which was melt with polylactic acid (PLA) as a reinforcement to obtain biomass UV-shielding film. The excellent UV absorption and antioxidant qualities of curcumin contributed to the impressive UV-shielding capacity (97.6% UV radiation absorption) and antioxidant (51% free radical scavenging) of PLA/CCPU-20 film. In the scanning electron microscopic images of film fracture, the mixing of CCPU elastomer into the PLA matrix caused the blend films to exhibit significant toughening fracture characteristics compared to the pure PLA film. The excellent thermal stability, low water swelling degree, and low water solubility of PLA/CCPU blend films were maintained after CCPU was added to the PLA matrix. Therefore, the PLA/CCPU blend films can be considered as a potential packaging material because of its favorable UV-shielding properties and film stability. Graphical abstract Schematic for the preparation of the PLA/CCPU blend films.","PeriodicalId":11806,"journal":{"name":"e-Polymers","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42375149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract In the present work, 4-methylcatechol oligomer has been prepared by using enzyme-catalyzed polymerization in water and preliminary evaluations as stabilizing agent in polypropylene (PP) was performed. In comparison with intrinsic PP, the oxidation onset temperature of the 4-methylcatechol oligomer/PP composite increased by 66°C, and the oxidation induction time increased by 40 min. In addition, the mixing of a 4-methylcatechol oligomer with PP (i.e., in the formation of a 4-methylcatechol oligomer/PP composite) did significantly enhance the long-term stability of PP in a thermal oxidative environment. Moreover, the tensile strength of this composite did not significantly decrease after aging for 800 h in an air atmosphere at 120°C. These results show that the addition of a 4-methylcatechol oligomer will markedly delay the aging and degradation of PP materials, even under extreme conditions. Thus, an enzyme-catalyzed polymerization of phenol compounds may provide a new avenue toward the preparation of novel antioxidants.
{"title":"Enzyme-catalyzed synthesis of 4-methylcatechol oligomer and preliminary evaluations as stabilizing agent in polypropylene","authors":"Yanpeng Wang, Fan Jiang, Lei Zhang","doi":"10.1515/epoly-2023-0008","DOIUrl":"https://doi.org/10.1515/epoly-2023-0008","url":null,"abstract":"Abstract In the present work, 4-methylcatechol oligomer has been prepared by using enzyme-catalyzed polymerization in water and preliminary evaluations as stabilizing agent in polypropylene (PP) was performed. In comparison with intrinsic PP, the oxidation onset temperature of the 4-methylcatechol oligomer/PP composite increased by 66°C, and the oxidation induction time increased by 40 min. In addition, the mixing of a 4-methylcatechol oligomer with PP (i.e., in the formation of a 4-methylcatechol oligomer/PP composite) did significantly enhance the long-term stability of PP in a thermal oxidative environment. Moreover, the tensile strength of this composite did not significantly decrease after aging for 800 h in an air atmosphere at 120°C. These results show that the addition of a 4-methylcatechol oligomer will markedly delay the aging and degradation of PP materials, even under extreme conditions. Thus, an enzyme-catalyzed polymerization of phenol compounds may provide a new avenue toward the preparation of novel antioxidants.","PeriodicalId":11806,"journal":{"name":"e-Polymers","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47729363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sajithkumar K. Jayaprakash, Suchith Chellappan, Sruthi A. Prasannan, V. Padil
Abstract Natural fibre composites are widespread for being eco-friendly and having unique properties. This study prepared nanocomposites by water evaporation using cellulose nanofibres (CNFs) as fillers and natural rubber (NR) latex as the matrix. Here, CNFs were extracted from the “pineapple fruit residue,” a waste material in juice industries. These fibre-reinforced nanocomposites were prepared under three different weight/volume percentages (5%, 10%, and 15%) and analysed for their mechanical and thermal properties. Furthermore, the morphology and distribution of CNFs in the NR matrix were examined by scanning electron microscopy and Fourier transform-infrared (FT-IR) analysis. The study found that CNFs were randomly oriented and evenly distributed in the nanocomposite. CNFs were detected by FT-IR spectroscopy in the NR matrix, as indicated by absorption peaks at 1,033 and 1,057 cm−1. Thermogravimetric analysis reveals increased thermal stability with more CNFs. Tensile strength and elastic modulus also increase. Pineapple fruit residue-based CNFs enhance mechanical and thermal properties of NR composites and can be considered an ideal natural reinforcing material.
{"title":"Pineapple fruit residue-based nanofibre composites: Preparation and characterizations","authors":"Sajithkumar K. Jayaprakash, Suchith Chellappan, Sruthi A. Prasannan, V. Padil","doi":"10.1515/epoly-2023-0094","DOIUrl":"https://doi.org/10.1515/epoly-2023-0094","url":null,"abstract":"Abstract Natural fibre composites are widespread for being eco-friendly and having unique properties. This study prepared nanocomposites by water evaporation using cellulose nanofibres (CNFs) as fillers and natural rubber (NR) latex as the matrix. Here, CNFs were extracted from the “pineapple fruit residue,” a waste material in juice industries. These fibre-reinforced nanocomposites were prepared under three different weight/volume percentages (5%, 10%, and 15%) and analysed for their mechanical and thermal properties. Furthermore, the morphology and distribution of CNFs in the NR matrix were examined by scanning electron microscopy and Fourier transform-infrared (FT-IR) analysis. The study found that CNFs were randomly oriented and evenly distributed in the nanocomposite. CNFs were detected by FT-IR spectroscopy in the NR matrix, as indicated by absorption peaks at 1,033 and 1,057 cm−1. Thermogravimetric analysis reveals increased thermal stability with more CNFs. Tensile strength and elastic modulus also increase. Pineapple fruit residue-based CNFs enhance mechanical and thermal properties of NR composites and can be considered an ideal natural reinforcing material.","PeriodicalId":11806,"journal":{"name":"e-Polymers","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49017837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Donglei Liu, Riqing Chen, Kai Zhan, Zizhi Chen, Xin Luo
Abstract Polyphenylene sulfide (PPS) and copper (Cu) were used as the polymer and substrate material to simulate the nano-injection molding process by molecular dynamics method. The results show that the PPS chain obeys Einstein’s diffusion law in the early stage of injection molding then deviates from it in the late stage due to the entanglement and limitation of surrounding nanoparticles. In addition, the process of conformational isomerization of polymer chains is accompanied by the twisting and stretching of fixed chains. There are two kinds of adhesion phenomena, one is the macromolecular slides violently in small areas of some sure nanoscale groove to form multiple anchor points. The other case involves multiple nano-grooves along the metal interface, the polymer chain slides and is bolted as multiple anchors in different grooves due to the exerted wall-drag effect on the neighboring chains. These two slipping and anchoring mechanisms are consistent with de Gennes’ slipping theory. Through the quantitative analysis of the influence of pressure on injection filling, it is found that injection pressure should be kept within a certain range to achieve the positive effect of molding.
{"title":"Study on wall-slipping mechanism of nano-injection polymer under the constant temperature fields","authors":"Donglei Liu, Riqing Chen, Kai Zhan, Zizhi Chen, Xin Luo","doi":"10.1515/epoly-2023-0085","DOIUrl":"https://doi.org/10.1515/epoly-2023-0085","url":null,"abstract":"Abstract Polyphenylene sulfide (PPS) and copper (Cu) were used as the polymer and substrate material to simulate the nano-injection molding process by molecular dynamics method. The results show that the PPS chain obeys Einstein’s diffusion law in the early stage of injection molding then deviates from it in the late stage due to the entanglement and limitation of surrounding nanoparticles. In addition, the process of conformational isomerization of polymer chains is accompanied by the twisting and stretching of fixed chains. There are two kinds of adhesion phenomena, one is the macromolecular slides violently in small areas of some sure nanoscale groove to form multiple anchor points. The other case involves multiple nano-grooves along the metal interface, the polymer chain slides and is bolted as multiple anchors in different grooves due to the exerted wall-drag effect on the neighboring chains. These two slipping and anchoring mechanisms are consistent with de Gennes’ slipping theory. Through the quantitative analysis of the influence of pressure on injection filling, it is found that injection pressure should be kept within a certain range to achieve the positive effect of molding.","PeriodicalId":11806,"journal":{"name":"e-Polymers","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135058054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This work investigated the thermal, morphological, and tensile properties of poly( l -lactide)- b -poly(ethylene glycol)- b -poly( l -lactide) (PLLA-PEG-PLLA)/thermoplastic starch (TPS) blends with 3 wt% citric acid (CA) treatment of TPS. The blends with PLLA-PEG-PLLA/CA-TPS ratios of 100/0, 90/10, 80/20, and 60/40 (w/w) were investigated and compared with PLLA-PEG-PLLA/CA-free TPS blends. Crystallizability of the blends decreased and thermal stability increased as the TPS content increased. The thermal stability of the blends was found to improve after CA treatment of TPS. The PLLA-PEG-PLLA/CA-TPS blends showed better phase compatibility than those of the PLLA-PEG-PLLA/CA-free TPS blends. The tensile properties of the blends were improved by CA treatment of TPS. In conclusion, improvement in thermal stability, phase compatibility, and tensile properties of the PLLA-PEG-PLLA/TPS blends was obtained by CA treatment of TPS. The resulting PLLA-PEG-PLLA/CA-TPS blends could potentially be used to prepare biodegradable and flexible bioplastics.
{"title":"Effect of citric acid on thermal, phase morphological, and mechanical properties of poly(l-lactide)-<i>b</i>-poly(ethylene glycol)-<i>b</i>-poly(l-lactide)/thermoplastic starch blends","authors":"Yaowalak Srisuwan, Prasong Srihanam, Theeraphol Phromsopha, Yodthong Baimark","doi":"10.1515/epoly-2023-0057","DOIUrl":"https://doi.org/10.1515/epoly-2023-0057","url":null,"abstract":"Abstract This work investigated the thermal, morphological, and tensile properties of poly( l -lactide)- b -poly(ethylene glycol)- b -poly( l -lactide) (PLLA-PEG-PLLA)/thermoplastic starch (TPS) blends with 3 wt% citric acid (CA) treatment of TPS. The blends with PLLA-PEG-PLLA/CA-TPS ratios of 100/0, 90/10, 80/20, and 60/40 (w/w) were investigated and compared with PLLA-PEG-PLLA/CA-free TPS blends. Crystallizability of the blends decreased and thermal stability increased as the TPS content increased. The thermal stability of the blends was found to improve after CA treatment of TPS. The PLLA-PEG-PLLA/CA-TPS blends showed better phase compatibility than those of the PLLA-PEG-PLLA/CA-free TPS blends. The tensile properties of the blends were improved by CA treatment of TPS. In conclusion, improvement in thermal stability, phase compatibility, and tensile properties of the PLLA-PEG-PLLA/TPS blends was obtained by CA treatment of TPS. The resulting PLLA-PEG-PLLA/CA-TPS blends could potentially be used to prepare biodegradable and flexible bioplastics.","PeriodicalId":11806,"journal":{"name":"e-Polymers","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135157128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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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