Pub Date : 2022-12-22DOI: 10.1177/09540083221146926
X. Xiong, Jianxin Ai, R. Ren, Jing Wang, Guiyang Li
The properties of a RTM bismaleimide resin with low viscosity and ultra-high temperature resistance were systematically investigated, including its curing kinetics and rheological properties, and the thermal and mechanical properties of its cured resins. The thermal curing kinetics was investigated by differential scanning calorimetry (DSC) method with multiple heating rates. DSC curves display a cure regime in the temperature range of 150∼300°C and the exothermic peaks shift from 194°C to 231°C with heating rate. The apparent activation energy of curing reaction is calculated as 78.2 kJ/mol. The rheological properties were studied in terms of the changes of the non-isothermal and isothermal viscosity tested using a rotary viscometer. The test results show that the RTM resin has a wide molding temperature window from 90°C to 200°C and long molding time at 110°C for 275 min with a flow viscosity less than 1000 mPas. Dual-Arrhenius model was established to predict the viscosity characteristics at different constant temperatures, showing a good agreement with the experimental data. Four curing cycles were designed to obtain cured networks with different microstructures, and the thermal and mechanical properties of the cured resins suffered from various curing cycles were characterized by dynamic mechanical analysis (DMA) and universal material testing machine. The results exhibit that the cured product has a ultra-high glass transition temperature of 373.5°C and larger flexural strength of 145.4 MPa after post-curing at 250°C for 10 h.
{"title":"Curing behavior and properties of ultra-high temperature resistant RTM bismaleimide resin","authors":"X. Xiong, Jianxin Ai, R. Ren, Jing Wang, Guiyang Li","doi":"10.1177/09540083221146926","DOIUrl":"https://doi.org/10.1177/09540083221146926","url":null,"abstract":"The properties of a RTM bismaleimide resin with low viscosity and ultra-high temperature resistance were systematically investigated, including its curing kinetics and rheological properties, and the thermal and mechanical properties of its cured resins. The thermal curing kinetics was investigated by differential scanning calorimetry (DSC) method with multiple heating rates. DSC curves display a cure regime in the temperature range of 150∼300°C and the exothermic peaks shift from 194°C to 231°C with heating rate. The apparent activation energy of curing reaction is calculated as 78.2 kJ/mol. The rheological properties were studied in terms of the changes of the non-isothermal and isothermal viscosity tested using a rotary viscometer. The test results show that the RTM resin has a wide molding temperature window from 90°C to 200°C and long molding time at 110°C for 275 min with a flow viscosity less than 1000 mPas. Dual-Arrhenius model was established to predict the viscosity characteristics at different constant temperatures, showing a good agreement with the experimental data. Four curing cycles were designed to obtain cured networks with different microstructures, and the thermal and mechanical properties of the cured resins suffered from various curing cycles were characterized by dynamic mechanical analysis (DMA) and universal material testing machine. The results exhibit that the cured product has a ultra-high glass transition temperature of 373.5°C and larger flexural strength of 145.4 MPa after post-curing at 250°C for 10 h.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46365159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-19DOI: 10.1177/09540083221146924
Liang Xu, Jing Xiao, Song Zhou
Different aging conditions have an important influence on the performance of carbon fiber composites. In this study, the properties of three-dimensional woven carbon fiber reinforced resin matrix composites were investigated and analyzed in three different aging environments (distilled water immersion, 30% H2SO4 solution immersion, and 10% NaOH solution immersion) at 60°C. Mass change, moisture absorption change, Fourier transform infrared spectra (FTIR), surface morphology before and after aging, glass transition temperature (Tg), compression properties, bending properties, and interlayer shear properties were analyzed. The results showed that the immersion in 10% NaOH solution made the specimens destroyed and the aging process was chemically changed. Distilled water immersion and 30% H2SO4 solution immersion moisture absorption rate to meet the FICK law, the aging process only physical changes. The surface of the composite specimens under the three aging conditions produced different degrees of cracks and different degrees of debonding at the interface between the fibers and the resin matrix. The Tg, flexural properties, interlaminar shear properties, and compressive properties of the aged specimens all showed different degrees of degradation.
{"title":"Study on the aging properties of 3D woven composites under corrosive conditions","authors":"Liang Xu, Jing Xiao, Song Zhou","doi":"10.1177/09540083221146924","DOIUrl":"https://doi.org/10.1177/09540083221146924","url":null,"abstract":"Different aging conditions have an important influence on the performance of carbon fiber composites. In this study, the properties of three-dimensional woven carbon fiber reinforced resin matrix composites were investigated and analyzed in three different aging environments (distilled water immersion, 30% H2SO4 solution immersion, and 10% NaOH solution immersion) at 60°C. Mass change, moisture absorption change, Fourier transform infrared spectra (FTIR), surface morphology before and after aging, glass transition temperature (Tg), compression properties, bending properties, and interlayer shear properties were analyzed. The results showed that the immersion in 10% NaOH solution made the specimens destroyed and the aging process was chemically changed. Distilled water immersion and 30% H2SO4 solution immersion moisture absorption rate to meet the FICK law, the aging process only physical changes. The surface of the composite specimens under the three aging conditions produced different degrees of cracks and different degrees of debonding at the interface between the fibers and the resin matrix. The Tg, flexural properties, interlaminar shear properties, and compressive properties of the aged specimens all showed different degrees of degradation.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41392242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-16DOI: 10.1177/09540083221145881
Hai-yan Sun, Yuanzhao Zhu, Hong Chao Xu, Yi Zhong, Linping Zhang, Yimeng Ma, X. Sui, Bijia Wang, Xueling Feng, Zhiping Mao
Polyphosphazene derivatives are gaining popularity due to their eco-friendly character and high content of flame-retardant components. Herein, a polyphosphazene derivative (PZAF) microsphere was successfully synthesized utilizing an in-situ template approach, which was then employed as an additive flame retardant in polyethylene terephthalate (PET) to improve the fire safety. Thermogravimetric analysis revealed that PZAF promoted the pyrolysis of PET in advance to generate a stable char layer that protects the matrix from heat, consequently increasing char residues. With addition of 10 wt% PZAF, the PET nanocomposites obtained a V-0 grade in vertical combustion test and its LOI value increased from 24.2 vol% to 32.1 vol%. Moreover, the peak heat release and carbon monoxide production decreased by 46.6% and 50.6%, respectively. This was because the phosphonic acid fragments and pyridine ring compounds produced by the PZAF pyrolysis encouraged the development of a robust char layer. Meanwhile, the •PO radicals generated by the pyrolysis of PZAF could capture free radicals in the gas phase, ultimately ending the chain reaction of combustion. Also, mechanical properties of the PET nanocomposites were noticeably enhanced by the addition of 3 or 5 wt% PZAF.
{"title":"Fire retardant polyethylene terephthalate containing 4,4′-(hexafluoroisopropylidene)diphenol-substituted cyclotriphosphazene microspheres","authors":"Hai-yan Sun, Yuanzhao Zhu, Hong Chao Xu, Yi Zhong, Linping Zhang, Yimeng Ma, X. Sui, Bijia Wang, Xueling Feng, Zhiping Mao","doi":"10.1177/09540083221145881","DOIUrl":"https://doi.org/10.1177/09540083221145881","url":null,"abstract":"Polyphosphazene derivatives are gaining popularity due to their eco-friendly character and high content of flame-retardant components. Herein, a polyphosphazene derivative (PZAF) microsphere was successfully synthesized utilizing an in-situ template approach, which was then employed as an additive flame retardant in polyethylene terephthalate (PET) to improve the fire safety. Thermogravimetric analysis revealed that PZAF promoted the pyrolysis of PET in advance to generate a stable char layer that protects the matrix from heat, consequently increasing char residues. With addition of 10 wt% PZAF, the PET nanocomposites obtained a V-0 grade in vertical combustion test and its LOI value increased from 24.2 vol% to 32.1 vol%. Moreover, the peak heat release and carbon monoxide production decreased by 46.6% and 50.6%, respectively. This was because the phosphonic acid fragments and pyridine ring compounds produced by the PZAF pyrolysis encouraged the development of a robust char layer. Meanwhile, the •PO radicals generated by the pyrolysis of PZAF could capture free radicals in the gas phase, ultimately ending the chain reaction of combustion. Also, mechanical properties of the PET nanocomposites were noticeably enhanced by the addition of 3 or 5 wt% PZAF.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44287825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-13DOI: 10.1177/09540083221143691
Dawei Lu, Xudong Zou, Chaofan Li
With the development of polymer science, more and more named reactions have been applied to synthesizing polymers. Introducing new reactions into polymer synthesis is undoubtedly an excellent expansion for monomer and polymer libraries. In this review, the named reactions employed in polymer-chain synthesis were divided into seven types: electrophilic reactions, nucleophilic reactions, transition metal-mediated cross-coupling reactions, free radical reactions, pericyclic reactions, multi-component reactions and rearrangement reactions. The discussion was mainly focused on the progress in the utilization of these named reactions in polymer synthesis, which could be a valuable reference for researchers in the polymer field.
{"title":"Advances in the application of named reactions in polymer synthesis","authors":"Dawei Lu, Xudong Zou, Chaofan Li","doi":"10.1177/09540083221143691","DOIUrl":"https://doi.org/10.1177/09540083221143691","url":null,"abstract":"With the development of polymer science, more and more named reactions have been applied to synthesizing polymers. Introducing new reactions into polymer synthesis is undoubtedly an excellent expansion for monomer and polymer libraries. In this review, the named reactions employed in polymer-chain synthesis were divided into seven types: electrophilic reactions, nucleophilic reactions, transition metal-mediated cross-coupling reactions, free radical reactions, pericyclic reactions, multi-component reactions and rearrangement reactions. The discussion was mainly focused on the progress in the utilization of these named reactions in polymer synthesis, which could be a valuable reference for researchers in the polymer field.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46250162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-06DOI: 10.1177/09540083221144257
P. V
The prepared mesoporous SBA-15 (Santa Barbara Amorphous-15) was sulfonated and used as filler for the preparation of sulfonated polysulfone based composite electrolyte membranes. The SBA-15 and polysulfone were sulfonated using 3-mercaptopropyl trimethoxysilane and trimethylsilyl chlorosulfonate, respectively. The different weight percentages (1, 3, and 5 wt%) of sulfonated SBA-15 (SSBA-15) were used to prepare composite electrolyte membranes. Water uptake, ion exchange capacity, swelling ratio and proton conductivity of the composite membranes were studied for assessing the suitability of the electrolyte membranes for use in fuel cells. Characterization techniques such as FT-IR, XRD, SEM, TEM and Brunauer–Emmett– Teller were used to study the physico-chemical properties of the electrolyte membranes. TEM and BET analysis showed that SBA -15 retained its mesoporous structure even after sulfonation process. The prepared membranes were then tested in an in-house built single-cell fuel cell using hydrogen as fuel and oxygen as the oxidant. The fuel cell study showed that the presence of Sulfonated SBA-15 in the polymer matrix provided additional ion exchange sites and retained water for proton transfer which resulted in higher power density of 815 mW/cm2 with SPSU + 3% SSBA-15 membrane as compared with Nafion 117®.
将制备的介孔SBA-15（Santa Barbara Amorphous-15）磺化并用作制备磺化聚砜基复合电解质膜的填料。SBA-15和聚砜分别用3-巯基丙基三甲氧基硅烷和三甲基甲硅烷基氯磺酸盐磺化。使用不同重量百分比（1、3和5wt%）的磺化SBA-15（SSBA-15）制备复合电解质膜。研究了复合膜的吸水率、离子交换容量、溶胀率和质子传导性，以评估电解质膜在燃料电池中的适用性。采用FT-IR、XRD、SEM、TEM和Brunauer–Emmett–Teller等表征技术对电解质膜的理化性质进行了研究。TEM和BET分析表明，SBA-15在磺化过程中仍保持着介孔结构。然后将制备的膜在内部构建的单电池燃料电池中进行测试，使用氢气作为燃料，氧气作为氧化剂。燃料电池研究表明，聚合物基质中磺化SBA-15的存在为质子转移提供了额外的离子交换位点和保留水，与Nafion 117®相比，SPSU+3%SSBA-15膜的功率密度更高，达到815 mW/cm2。
{"title":"Influence of sulfonated SBA - 15 on fuel cell performance of sulfonated polysulfone electrolyte membranes","authors":"P. V","doi":"10.1177/09540083221144257","DOIUrl":"https://doi.org/10.1177/09540083221144257","url":null,"abstract":"The prepared mesoporous SBA-15 (Santa Barbara Amorphous-15) was sulfonated and used as filler for the preparation of sulfonated polysulfone based composite electrolyte membranes. The SBA-15 and polysulfone were sulfonated using 3-mercaptopropyl trimethoxysilane and trimethylsilyl chlorosulfonate, respectively. The different weight percentages (1, 3, and 5 wt%) of sulfonated SBA-15 (SSBA-15) were used to prepare composite electrolyte membranes. Water uptake, ion exchange capacity, swelling ratio and proton conductivity of the composite membranes were studied for assessing the suitability of the electrolyte membranes for use in fuel cells. Characterization techniques such as FT-IR, XRD, SEM, TEM and Brunauer–Emmett– Teller were used to study the physico-chemical properties of the electrolyte membranes. TEM and BET analysis showed that SBA -15 retained its mesoporous structure even after sulfonation process. The prepared membranes were then tested in an in-house built single-cell fuel cell using hydrogen as fuel and oxygen as the oxidant. The fuel cell study showed that the presence of Sulfonated SBA-15 in the polymer matrix provided additional ion exchange sites and retained water for proton transfer which resulted in higher power density of 815 mW/cm2 with SPSU + 3% SSBA-15 membrane as compared with Nafion 117®.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49656502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-28DOI: 10.1177/09540083221143688
M. Derradji, Karim Khiari, Oussama Mehelli, S. Abdous, Abdelmalek Habes, Noureddine Ramdani, Abdeljalil Zegaoui, Wen-ben Liu, A. Daham
By following the rules of green chemistry, a novel composite is developed from a renewable and ecofriendly resource, namely the vanillin. The latter was used as a phenolic precursor for the microwave synthesis of a bio-based benzoxazine resin (Va-BZ). Afterwards, high performance green composites were developed by reinforcing the Va-BZ with various amounts of chopped silane surface modified basalt fibers (BFs). The chemical structure of the Va-BZ monomers was confirmed by 1H NMR and FTIR spectroscopy. The grafting of the silane moiety on the BFs surface was assessed by FTIR and TGA analyses. The autocatalytic ring opening polymerization of the Va-BZ monomers was confirmed by DSC analysis. The mechanical performances of the developed green composites were studied by flexural and tensile investigations. The findings suggested that the maximum amount of 20 wt. BFs afforded the best results, with flexural and tensile strengths of 447 and 460 MPa, respectively. The SEM was used to study the fractured tensile surfaces and elucidated the toughening mechanism. Meanwhile, the TGA showed that the introduction of the BFs markedly improved the thermal stability of the benzoxazine matrix. Finally, the gamma rays shielding effectiveness was studied and revealed the highly benefic role of the BFs. For instance, a 1 cm thick Va-BZ polymer only showed a 6% gamma rays screening ratio, the latter was improved to 18.4% for the composite made of 20 wt.% of treated BFs. Overall, this study confirmed that greener approaches can also result in high performance composite satisfying the needs of exigent applications.
{"title":"Mechanical and thermal properties of fully green composites from vanillin-based benzoxazine and silane surface modified chopped basalt fibers","authors":"M. Derradji, Karim Khiari, Oussama Mehelli, S. Abdous, Abdelmalek Habes, Noureddine Ramdani, Abdeljalil Zegaoui, Wen-ben Liu, A. Daham","doi":"10.1177/09540083221143688","DOIUrl":"https://doi.org/10.1177/09540083221143688","url":null,"abstract":"By following the rules of green chemistry, a novel composite is developed from a renewable and ecofriendly resource, namely the vanillin. The latter was used as a phenolic precursor for the microwave synthesis of a bio-based benzoxazine resin (Va-BZ). Afterwards, high performance green composites were developed by reinforcing the Va-BZ with various amounts of chopped silane surface modified basalt fibers (BFs). The chemical structure of the Va-BZ monomers was confirmed by 1H NMR and FTIR spectroscopy. The grafting of the silane moiety on the BFs surface was assessed by FTIR and TGA analyses. The autocatalytic ring opening polymerization of the Va-BZ monomers was confirmed by DSC analysis. The mechanical performances of the developed green composites were studied by flexural and tensile investigations. The findings suggested that the maximum amount of 20 wt. BFs afforded the best results, with flexural and tensile strengths of 447 and 460 MPa, respectively. The SEM was used to study the fractured tensile surfaces and elucidated the toughening mechanism. Meanwhile, the TGA showed that the introduction of the BFs markedly improved the thermal stability of the benzoxazine matrix. Finally, the gamma rays shielding effectiveness was studied and revealed the highly benefic role of the BFs. For instance, a 1 cm thick Va-BZ polymer only showed a 6% gamma rays screening ratio, the latter was improved to 18.4% for the composite made of 20 wt.% of treated BFs. Overall, this study confirmed that greener approaches can also result in high performance composite satisfying the needs of exigent applications.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44687244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-24DOI: 10.1177/09540083221142758
Rui Chen, Bao Dongmei, Jiaye Jiang, Chuanbo Sun, Han Chen, M. Zhang
Two effective flame retardant additives hsalaminopyridine phosphaphenanthrene (HAD) and methoaminopyridine phosphaphenanthrene (MAD) were respectively prepared with DOPO, aminopyridine, salicylaldehyde and 3-Methoxysalicylaldehyde. Subsequently, HAD and MAD was added into epoxy resin (EP) respectively, and flame retardancy of EP/HAD and EP/MAD thermosets were dramatically enhanced. The result of cone calorimeter (CC) test revealed that both HAD and MAD showed perfect smoke suppression performance. In respect of transmittance and mechanical properties, there was a huge difference between HAD and MAD. The introduction of HAD dramatically harmed transmittance and mechanical properties of EP, while, EP/10%MAD was transparent and nearly possessed the same mechanical properties with pure EP.
{"title":"Effect of 3-methoxysalicylaldehyde on transparency and mechanical properties of EP modified with aminopyridine-based DOPO derivative","authors":"Rui Chen, Bao Dongmei, Jiaye Jiang, Chuanbo Sun, Han Chen, M. Zhang","doi":"10.1177/09540083221142758","DOIUrl":"https://doi.org/10.1177/09540083221142758","url":null,"abstract":"Two effective flame retardant additives hsalaminopyridine phosphaphenanthrene (HAD) and methoaminopyridine phosphaphenanthrene (MAD) were respectively prepared with DOPO, aminopyridine, salicylaldehyde and 3-Methoxysalicylaldehyde. Subsequently, HAD and MAD was added into epoxy resin (EP) respectively, and flame retardancy of EP/HAD and EP/MAD thermosets were dramatically enhanced. The result of cone calorimeter (CC) test revealed that both HAD and MAD showed perfect smoke suppression performance. In respect of transmittance and mechanical properties, there was a huge difference between HAD and MAD. The introduction of HAD dramatically harmed transmittance and mechanical properties of EP, while, EP/10%MAD was transparent and nearly possessed the same mechanical properties with pure EP.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45225568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-17DOI: 10.1177/09540083221140015
W. Monzel, Kyle Berglund, M. Kolel-Veetil, D. Simone, T. Gibson
The realization of aerospace vehicle technologies demanding extreme service conditions is facilitated by the development of materials with greater oxidative stability at high temperatures. Thermal performance of polymer composites can be increased by incorporating a hybrid (organic-inorganic) resin as a thermal barrier coating. One such resin system, meta-poly (carborane-siloxane-arylacetylene) (m-PCSAA), developed by the U.S. Naval Research Laboratory, shows potential for such application and is further investigated in this work. The resin has a low viscosity (0.1 Pa s) with large processing window (2.5 h) from 100°C to 230°C. These processing characteristics are advantageous for infusion processes or the inclusion of fillers for coating applications. Curing was accomplished in two stages, corresponding to two exothermic reactions. After the first curing stage, the resin exhibits elastomeric behavior, and after the second curing stage is rigid with a high glass transition temperature (∼330°C). The materials exhibited high char yields (89%) in air at 1000°C and may be useful in space or for attritable technology. No cracks were observed during long-term service at 288°C, but significant degradation and cracking were observed after aging at 316°C. The materials exhibited high coefficients of thermal expansion; 186.9 and 168.6 μm/(m∙°C) after first and second curing stage respectively. Similar to epoxies and polyimides, the resin acquired up to 3% moisture at 70°C and 85% relative humidity.
在高温下具有更大氧化稳定性的材料的发展促进了对极端使用条件要求的航空航天飞行器技术的实现。聚合物复合材料的热性能可以通过加入混合(有机-无机)树脂作为热障涂层来提高。由美国海军研究实验室开发的一种这样的树脂体系，间聚(碳硼烷-硅氧烷-芳基乙炔)(m-PCSAA)，显示了这种应用的潜力，并在这项工作中得到了进一步的研究。该树脂具有低粘度(0.1 Pa s)，在100°C至230°C范围内具有大的加工窗口(2.5 h)。这些加工特性有利于灌注工艺或包含用于涂层应用的填料。固化分两个阶段完成，对应于两个放热反应。在第一阶段固化后，树脂表现出弹性体行为，在第二阶段固化后，树脂具有高玻璃化转变温度(~ 330°C)的刚性。该材料在1000°C的空气中表现出高炭产率(89%)，可用于太空或可降解技术。在288℃长期使用期间未观察到裂纹，但在316℃时效后出现了明显的降解和裂纹。材料表现出较高的热膨胀系数;第一期和第二期固化后的温度分别为186.9和168.6 μm/(m∙°C)。与环氧树脂和聚酰亚胺类似，该树脂在70°C和85%的相对湿度下可获得高达3%的水分。
{"title":"The evaluation of an inorganic-organic poly(carborane-siloxane-arylacetylene) hybrid resin system","authors":"W. Monzel, Kyle Berglund, M. Kolel-Veetil, D. Simone, T. Gibson","doi":"10.1177/09540083221140015","DOIUrl":"https://doi.org/10.1177/09540083221140015","url":null,"abstract":"The realization of aerospace vehicle technologies demanding extreme service conditions is facilitated by the development of materials with greater oxidative stability at high temperatures. Thermal performance of polymer composites can be increased by incorporating a hybrid (organic-inorganic) resin as a thermal barrier coating. One such resin system, meta-poly (carborane-siloxane-arylacetylene) (m-PCSAA), developed by the U.S. Naval Research Laboratory, shows potential for such application and is further investigated in this work. The resin has a low viscosity (0.1 Pa s) with large processing window (2.5 h) from 100°C to 230°C. These processing characteristics are advantageous for infusion processes or the inclusion of fillers for coating applications. Curing was accomplished in two stages, corresponding to two exothermic reactions. After the first curing stage, the resin exhibits elastomeric behavior, and after the second curing stage is rigid with a high glass transition temperature (∼330°C). The materials exhibited high char yields (89%) in air at 1000°C and may be useful in space or for attritable technology. No cracks were observed during long-term service at 288°C, but significant degradation and cracking were observed after aging at 316°C. The materials exhibited high coefficients of thermal expansion; 186.9 and 168.6 μm/(m∙°C) after first and second curing stage respectively. Similar to epoxies and polyimides, the resin acquired up to 3% moisture at 70°C and 85% relative humidity.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41389294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-17DOI: 10.1177/09540083221140755
X. Zhong, Lian-Ping Zhang, J. Bao, Weidong Li, Hansong Liu, B. Dong
In this work, the epoxy resin cured with chlorinated fluorene amine as the curing agent was obtained, which significantly increased the resin modulus and did not reduce the impact toughness, compared with the common curing system. Al2O3 nanoparticles were used to stiffen the new curing epoxy system, which did not reduce the compression strength of the resin but increased the compression modulus. The microscopic morphology showed that the rigid particles were uniformly dispersed in the resin matrix, and the addition of rigid particles mildly affected the reactional and rheological properties of the resin system. The minimum viscosity of the matrix increased with the additional number of particles. The composite was prepared using the nanoparticle-modified epoxy resin with carbon fiber (CF), and the compression strength of the composite was significantly improved by nearly 30% compared with that composed of the common epoxy system.
{"title":"Preparation and compression mechanical properties of carbon fiber/epoxy nanoparticle composites","authors":"X. Zhong, Lian-Ping Zhang, J. Bao, Weidong Li, Hansong Liu, B. Dong","doi":"10.1177/09540083221140755","DOIUrl":"https://doi.org/10.1177/09540083221140755","url":null,"abstract":"In this work, the epoxy resin cured with chlorinated fluorene amine as the curing agent was obtained, which significantly increased the resin modulus and did not reduce the impact toughness, compared with the common curing system. Al2O3 nanoparticles were used to stiffen the new curing epoxy system, which did not reduce the compression strength of the resin but increased the compression modulus. The microscopic morphology showed that the rigid particles were uniformly dispersed in the resin matrix, and the addition of rigid particles mildly affected the reactional and rheological properties of the resin system. The minimum viscosity of the matrix increased with the additional number of particles. The composite was prepared using the nanoparticle-modified epoxy resin with carbon fiber (CF), and the compression strength of the composite was significantly improved by nearly 30% compared with that composed of the common epoxy system.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49088149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-04DOI: 10.1177/09540083221135499
Yanmei Wang, Yanen Wang, Minyan Liu, Q. Wei, B. Du
In this work, a series of polylactic acid/thermoplastic polyurethane/polyaniline (PLA/TPU/PANI) blends with different weight ratios were prepared by Fused deposition molding First, six groups of PLA/TPU (U9A1/U8A2/U7A3/U6A4/U5A5/U4A6) and three groups of PLA/TPU/PANI (821/823/825) with different ratios were fabricated by melt blending. Then, the effects of different filament forming and printing process parameters on print resolution and quality were investigated. Next, printed samples were characterized by Fourier transform infrared (FTIR), Thermogravimetric analysis (TGA), Scanning electron microscopy (SEM) and mechanical experiments. The results of FTIR and TGA showed no chemical reaction between different components, and uniform distribution of the material was observed in the SEM. The tensile and compressive curves of the samples showed an inverted U-shape. Finally, the shape-memory property was evaluated by differential scanning calorimetry. For PLA/TPU blends, U8A2 had the best shape memory capability ( R r = 80.8% and R f = 100%). Based on the excellent shape memory performance of PLA/TPU, the addition of PANI can introduce a light-actuated mechanism to form a binary-driven shape memory material. The composite materials prepared in this work can be applied to tissue engineering scaffolds, medical devices, soft robots and so on. Graphical Abstract
{"title":"4D printing light-/thermo-responsive shape memory composites based on thermoplastic polyurethane/polylactic acid/polyaniline blends","authors":"Yanmei Wang, Yanen Wang, Minyan Liu, Q. Wei, B. Du","doi":"10.1177/09540083221135499","DOIUrl":"https://doi.org/10.1177/09540083221135499","url":null,"abstract":"In this work, a series of polylactic acid/thermoplastic polyurethane/polyaniline (PLA/TPU/PANI) blends with different weight ratios were prepared by Fused deposition molding First, six groups of PLA/TPU (U9A1/U8A2/U7A3/U6A4/U5A5/U4A6) and three groups of PLA/TPU/PANI (821/823/825) with different ratios were fabricated by melt blending. Then, the effects of different filament forming and printing process parameters on print resolution and quality were investigated. Next, printed samples were characterized by Fourier transform infrared (FTIR), Thermogravimetric analysis (TGA), Scanning electron microscopy (SEM) and mechanical experiments. The results of FTIR and TGA showed no chemical reaction between different components, and uniform distribution of the material was observed in the SEM. The tensile and compressive curves of the samples showed an inverted U-shape. Finally, the shape-memory property was evaluated by differential scanning calorimetry. For PLA/TPU blends, U8A2 had the best shape memory capability ( R r = 80.8% and R f = 100%). Based on the excellent shape memory performance of PLA/TPU, the addition of PANI can introduce a light-actuated mechanism to form a binary-driven shape memory material. The composite materials prepared in this work can be applied to tissue engineering scaffolds, medical devices, soft robots and so on. Graphical Abstract","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45268370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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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