Pub Date : 2023-10-19DOI: 10.1177/09540083231209487
Bing Xu, Zhipeng Zhang, Hongtan Liang, Jie Hu, Lixiang Chen, Zhen Wang, Bo Chai, Guozhi Fan
Polyimide aerogel, presenting an outstanding new material for lightweight protective thermal insulation, has garnered significant attention in the aerospace field. Despite its potential, due to the high production cost of the supercritical drying method used for its preparation, its widespread application is limited. In this research, a series of lightweight polyimide aerogels (F-PIAs, 3,3',4,4'-biphenyl tetracarboxylic dianhydride (s-BPDA) and 4,4'-diaminodiphenyl ether (ODA)) with excellent thermal protection properties were prepared by lyophilization. The findings indicated that F-PIAs (Freeze-dried polyimide aerogels) exhibited comparable physical characteristics to S-PIAs (Supercritical-dried polyimide aerogels), while their preparation cost was even more economical. F-PIAs exhibits excellent flexible and compression behavior (compression strength up to 1.16 MPa, modulus up to 12.8 MPa), which provide a great structural basis for the production of molded thermal insulation protective materials. The average pore diameter of F-PIAs is in the range of 7∼11 nm. The nanoporous structure leads to the gas within the pores of the aerogel producing the Knudsen effect, thereby significantly enhancing the thermal insulation performance of the aerogel. The thermal conductivity of F-PIA-4 (Freeze-dried polyimide aerogels with a solid content of 4%) at room temperature is as low as 0.023 W·m −1 ·K −1 , which is superior to the PIAs (0.043 W·m −1 ·K −1 ) prepared by lyophilization in literature. Its thermal diffusion coefficient changes from 0.108 mm 2 ·s −1 to 0.18 mm 2 ·s −1 in the temperature range of 27°C to 200°C, demonstrating good thermal insulation performance at high temperatures. Meanwhile, after heating on a 150°C flat plate for 11 min and 41 s, the surface temperature of F-PIA-4 was only 36.2°C, further verifying its excellent thermal insulation performance. The results of the TGA experiment on F-PIA-4 demonstrated the high-temperature stability of aerogel (Td5% is higher than 523°C, Td10% is higher than 566°C). The exceptional properties of F-PIAs hold significant practical reference value in helping to reduce the manufacturing cost of high-performance aerogel thermal insulation materials, thereby enabling their widespread application in aerospace, military, and civil field.
聚酰亚胺气凝胶作为一种新型的轻质防护隔热材料，在航空航天领域引起了广泛的关注。尽管其潜力巨大，但由于制备所用的超临界干燥方法生产成本高，限制了其广泛应用。本研究通过冻干法制备了一系列具有优良热防护性能的轻质聚酰亚胺气凝胶(F-PIAs, 3,3′，4,4′-联苯四羧酸二酐(s-BPDA)和4,4′-二氨基二苯醚(ODA))。研究结果表明，冻干聚酰亚胺气凝胶(F-PIAs)具有与超临界干燥聚酰亚胺气凝胶(S-PIAs)相当的物理特性，而其制备成本更经济。F-PIAs具有优异的柔韧性和抗压性能(抗压强度可达1.16 MPa，模量可达12.8 MPa)，为成型保温防护材料的生产提供了良好的结构基础。F-PIAs的平均孔径在7 ~ 11 nm之间。纳米孔结构导致气凝胶孔隙内的气体产生克努森效应，从而显著提高气凝胶的保温性能。F-PIA-4(冷冻干燥聚酰亚胺气凝胶，固含量为4%)的室温热导率低至0.023 W·m−1·K−1，优于文献中冻干法制备的pia (0.043 W·m−1·K−1)。在27℃~ 200℃温度范围内，其热扩散系数在0.108 mm 2·s−1 ~ 0.18 mm 2·s−1之间变化，具有良好的高温保温性能。同时，在150℃的平板上加热11 min 41 s后，F-PIA-4的表面温度仅为36.2℃，进一步验证了其优异的保温性能。对F-PIA-4的TGA实验结果表明，气凝胶具有高温稳定性(Td5%高于523℃，Td10%高于566℃)。F-PIAs的优异性能对降低高性能气凝胶保温材料的制造成本具有重要的实用参考价值，从而使其在航空航天、军事和民用领域得到广泛应用。
{"title":"Polyimide aerogels with low thermal conductivity and high-temperature stable properties prepared by lyophilization for flexible thermal protection","authors":"Bing Xu, Zhipeng Zhang, Hongtan Liang, Jie Hu, Lixiang Chen, Zhen Wang, Bo Chai, Guozhi Fan","doi":"10.1177/09540083231209487","DOIUrl":"https://doi.org/10.1177/09540083231209487","url":null,"abstract":"Polyimide aerogel, presenting an outstanding new material for lightweight protective thermal insulation, has garnered significant attention in the aerospace field. Despite its potential, due to the high production cost of the supercritical drying method used for its preparation, its widespread application is limited. In this research, a series of lightweight polyimide aerogels (F-PIAs, 3,3',4,4'-biphenyl tetracarboxylic dianhydride (s-BPDA) and 4,4'-diaminodiphenyl ether (ODA)) with excellent thermal protection properties were prepared by lyophilization. The findings indicated that F-PIAs (Freeze-dried polyimide aerogels) exhibited comparable physical characteristics to S-PIAs (Supercritical-dried polyimide aerogels), while their preparation cost was even more economical. F-PIAs exhibits excellent flexible and compression behavior (compression strength up to 1.16 MPa, modulus up to 12.8 MPa), which provide a great structural basis for the production of molded thermal insulation protective materials. The average pore diameter of F-PIAs is in the range of 7∼11 nm. The nanoporous structure leads to the gas within the pores of the aerogel producing the Knudsen effect, thereby significantly enhancing the thermal insulation performance of the aerogel. The thermal conductivity of F-PIA-4 (Freeze-dried polyimide aerogels with a solid content of 4%) at room temperature is as low as 0.023 W·m −1 ·K −1 , which is superior to the PIAs (0.043 W·m −1 ·K −1 ) prepared by lyophilization in literature. Its thermal diffusion coefficient changes from 0.108 mm 2 ·s −1 to 0.18 mm 2 ·s −1 in the temperature range of 27°C to 200°C, demonstrating good thermal insulation performance at high temperatures. Meanwhile, after heating on a 150°C flat plate for 11 min and 41 s, the surface temperature of F-PIA-4 was only 36.2°C, further verifying its excellent thermal insulation performance. The results of the TGA experiment on F-PIA-4 demonstrated the high-temperature stability of aerogel (Td5% is higher than 523°C, Td10% is higher than 566°C). The exceptional properties of F-PIAs hold significant practical reference value in helping to reduce the manufacturing cost of high-performance aerogel thermal insulation materials, thereby enabling their widespread application in aerospace, military, and civil field.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135779808","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}
The development of novel nanomaterials with superior reflection loss (RL), thin thickness, wide bandwidth, and low density has recently received significant attention in an effort to increase their effectiveness in electromagnetic (EM) microwave absorption while maintaining an easy manufacturing process. Naturally, using conventional materials with magnetic or dielectric loss makes it difficult to achieve the last criterion and limitations the thickness of the absorber and mass production. In this work, microwave nanocomposites samples were prepared on epoxy resin with different percentages of the nanoparticles of aluminum oxide (epoxy/Al 2 O 3 ) with surfaces treated by amino propyl and silane. The surface treatment was carried out to improve the adhesion, morphology, and EM properties of the samples to enhance the microwave absorption and the Shielding Effectiveness (SE). Therefore, the treated sample can be considered as potential candidate for high frequency EM absorption applications. Then, the study is followed by structural, morphological, thermal, and electrical characterization of the prepared samples in order to enhance the performances of the latters. The EM absorption and the shielding effectiveness were done in the X band frequency (8 GHz-12 GHz). The obtained results confirmed that the nanocomposites treated samples exhibit higher EM absorption performance and better electrical characteristics. Overall, these results put forward the role played by the addition of the nanoparticles films as high-performance materials in electronic devices and EM applications.
{"title":"Enhancing electromagnetic absorption in microwave of epoxy resin through incorporated surface modified aluminum oxide nanoparticles","authors":"Youcef Amine Medjaouri, Achour Ales, Oussama Mehelli, Redouane Tahmi, Karim Benzaoui, Abdelmalek Habes, Mehdi Derradji","doi":"10.1177/09540083231206563","DOIUrl":"https://doi.org/10.1177/09540083231206563","url":null,"abstract":"The development of novel nanomaterials with superior reflection loss (RL), thin thickness, wide bandwidth, and low density has recently received significant attention in an effort to increase their effectiveness in electromagnetic (EM) microwave absorption while maintaining an easy manufacturing process. Naturally, using conventional materials with magnetic or dielectric loss makes it difficult to achieve the last criterion and limitations the thickness of the absorber and mass production. In this work, microwave nanocomposites samples were prepared on epoxy resin with different percentages of the nanoparticles of aluminum oxide (epoxy/Al 2 O 3 ) with surfaces treated by amino propyl and silane. The surface treatment was carried out to improve the adhesion, morphology, and EM properties of the samples to enhance the microwave absorption and the Shielding Effectiveness (SE). Therefore, the treated sample can be considered as potential candidate for high frequency EM absorption applications. Then, the study is followed by structural, morphological, thermal, and electrical characterization of the prepared samples in order to enhance the performances of the latters. The EM absorption and the shielding effectiveness were done in the X band frequency (8 GHz-12 GHz). The obtained results confirmed that the nanocomposites treated samples exhibit higher EM absorption performance and better electrical characteristics. Overall, these results put forward the role played by the addition of the nanoparticles films as high-performance materials in electronic devices and EM applications.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135824436","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 : 2023-10-16DOI: 10.1177/09540083231207788
Zhenyu Huang, Zhengzhou Wang
Epoxy resin/cyanate ester copolymer (EC) possesses the advantages of low dielectric constant and low dielectric loss, while the easy flammability of EC restricts its applications. The effect of 10-(2,5-dihydroxyphenyl)-10-hydrogen-9-oxa-10-phosphazephenanthrene-10-oxide (DQ) and copper hydroxystannate (CuHS) on the flame retardancy, smoke suppression, mechanical properties and thermal decomposition behavior of EC was studied. The EC composite containing 7 wt% DQ and 3 wt% CuHS (EC/7DQ3CuHS) passed the UL-94 V0 rating with a limiting oxygen index of 32.0% The peak heat release rate and total heat release of EC/7DQ3CuHS fell by 41.9% and 35.0% respectively, compared with those of pure EC. The total smoke release of EC/7DQ3CuHS was reduced by 36.0% in comparison with that of the EC composite containing 10 wt% DQ. The tensile and impact strengths of the EC composite with 9 wt% DQ and 1 wt% CuHS increased by 16.9% and 19.2%, respectively in contrast with pure EC. The dielectric constant and dielectric loss of the EC composites maintained at relative low values. The as-prepared EC composites have application prospect in electronic packaging industry.
{"title":"Epoxy resin/cyannate ester copolymer with improved fire safety, mechanical properties and low dielectric loss enabled by 10-(2,5-dihydroxyphenyl)-10-hydrogen-9-oxa-10-phosphazephenanthrene-10-oxide and copper hydroxystannate","authors":"Zhenyu Huang, Zhengzhou Wang","doi":"10.1177/09540083231207788","DOIUrl":"https://doi.org/10.1177/09540083231207788","url":null,"abstract":"Epoxy resin/cyanate ester copolymer (EC) possesses the advantages of low dielectric constant and low dielectric loss, while the easy flammability of EC restricts its applications. The effect of 10-(2,5-dihydroxyphenyl)-10-hydrogen-9-oxa-10-phosphazephenanthrene-10-oxide (DQ) and copper hydroxystannate (CuHS) on the flame retardancy, smoke suppression, mechanical properties and thermal decomposition behavior of EC was studied. The EC composite containing 7 wt% DQ and 3 wt% CuHS (EC/7DQ3CuHS) passed the UL-94 V0 rating with a limiting oxygen index of 32.0% The peak heat release rate and total heat release of EC/7DQ3CuHS fell by 41.9% and 35.0% respectively, compared with those of pure EC. The total smoke release of EC/7DQ3CuHS was reduced by 36.0% in comparison with that of the EC composite containing 10 wt% DQ. The tensile and impact strengths of the EC composite with 9 wt% DQ and 1 wt% CuHS increased by 16.9% and 19.2%, respectively in contrast with pure EC. The dielectric constant and dielectric loss of the EC composites maintained at relative low values. The as-prepared EC composites have application prospect in electronic packaging industry.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136113566","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 : 2023-10-12DOI: 10.1177/09540083231206532
Abdelwahed Berrouane, Mehdi Derradji, Karim Khiari, Oussama Mehelli, Abdelmalek Habes, Slimane Abdous, Bouchra Amri, Mohamed El Amine Kadi, Wenbin Liu
In an attempt to make polybenzoxazines more sustainable, a novel bio-based benzoxazine monomer namely Q-Bz was synthetized via the Mannich condensation reaction utilizing Quercetin, paraformaldehyde and aniline. The chemical structure of the monomer was confirmed by 1 H nuclear magnetic resonance ( 1 H NMR) and Fourier transform infrared spectroscopies (FTIR). The curing behaviour was studied by differential scanning calorimetry (DSC) and the polymerization process was investigated by FTIR. The obtained results showed very low melting and polymerization temperatures (73 and 183°C, respectively) and the disappearance of the oxazine ring absorption bands due to the ring opening polymerization of the monomers. Afterwards, the cured bio-based thermoset, referred to as PQ-Bz, was obtained and its thermal stability and thermo-mechanical properties were also assessed by DSC and thermogravimetric analysis (TGA). As expected the newly developed thermoset exhibited high thermal stability along with excellent processability. Indeed, the results showed that PQ-Bz had a relatively high T g of approximately 280°C, with a 53% char yield at 800°C, 5% and 10% weight reduction temperature (T 5% and T 10% ) values of 349 and 373°C, respectively. These findings demonstrate the potential of the novel bio-based benzoxazine monomer as a sustainable alternative to traditional petroleum-based thermosets in high performance applications.
{"title":"Sustainable synthesis of a novel bio-based low temperature curable benzoxazine monomer from quercetin: Synthesis, curing reaction and thermal properties","authors":"Abdelwahed Berrouane, Mehdi Derradji, Karim Khiari, Oussama Mehelli, Abdelmalek Habes, Slimane Abdous, Bouchra Amri, Mohamed El Amine Kadi, Wenbin Liu","doi":"10.1177/09540083231206532","DOIUrl":"https://doi.org/10.1177/09540083231206532","url":null,"abstract":"In an attempt to make polybenzoxazines more sustainable, a novel bio-based benzoxazine monomer namely Q-Bz was synthetized via the Mannich condensation reaction utilizing Quercetin, paraformaldehyde and aniline. The chemical structure of the monomer was confirmed by 1 H nuclear magnetic resonance ( 1 H NMR) and Fourier transform infrared spectroscopies (FTIR). The curing behaviour was studied by differential scanning calorimetry (DSC) and the polymerization process was investigated by FTIR. The obtained results showed very low melting and polymerization temperatures (73 and 183°C, respectively) and the disappearance of the oxazine ring absorption bands due to the ring opening polymerization of the monomers. Afterwards, the cured bio-based thermoset, referred to as PQ-Bz, was obtained and its thermal stability and thermo-mechanical properties were also assessed by DSC and thermogravimetric analysis (TGA). As expected the newly developed thermoset exhibited high thermal stability along with excellent processability. Indeed, the results showed that PQ-Bz had a relatively high T g of approximately 280°C, with a 53% char yield at 800°C, 5% and 10% weight reduction temperature (T 5% and T 10% ) values of 349 and 373°C, respectively. These findings demonstrate the potential of the novel bio-based benzoxazine monomer as a sustainable alternative to traditional petroleum-based thermosets in high performance applications.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136014421","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 : 2023-09-30DOI: 10.1177/09540083231204218
Lei Li, Rui Yuan, Sucheng Yang, Li Yang, Guanjun Chang, Ying Huang
It is of great significance to enhance mechanical properties and thermal stability of high-performance polymers. A new coordination polymer film (Ni/PPy) with high tensile strength and excellent heat resistance has been successfully prepared via a palladium-catalyzed C-C coupling reaction. For newly synthesized polymer film, bipyridine is incorporated into polymer chains during the synthesis process and subsequently crosslinked by nickel acetate. More importantly, Ni-coordination can be removed by external pyrophosphate to recover the linear polymer, which endows the polymer with recyclability. This strategy is expected to be an effective means for increasing the mechanical properties and recyclability of high-performance polymer materials.
{"title":"A facile strategy to improve the strength and toughness of high-performance polymer and recycle by dynamic Ni-coordination crosslinking","authors":"Lei Li, Rui Yuan, Sucheng Yang, Li Yang, Guanjun Chang, Ying Huang","doi":"10.1177/09540083231204218","DOIUrl":"https://doi.org/10.1177/09540083231204218","url":null,"abstract":"It is of great significance to enhance mechanical properties and thermal stability of high-performance polymers. A new coordination polymer film (Ni/PPy) with high tensile strength and excellent heat resistance has been successfully prepared via a palladium-catalyzed C-C coupling reaction. For newly synthesized polymer film, bipyridine is incorporated into polymer chains during the synthesis process and subsequently crosslinked by nickel acetate. More importantly, Ni-coordination can be removed by external pyrophosphate to recover the linear polymer, which endows the polymer with recyclability. This strategy is expected to be an effective means for increasing the mechanical properties and recyclability of high-performance polymer materials.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136336486","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}
Photosensitive polyimide (PSPI) have been developed base on polyimide (PI). PSPI can be used as insulating and protective materials in the microelectronics industry due to the excellent insulating properties, thermal stability, and chemical stability. In this work, we designed a synthetic method to improve the regularity of the polymer chain segment sequence. Quaternary block copolymerized precursors were prepared using condensation polymerization of poly (acid amid). A photosensitive poly (acid amid) salts (co-PAS) was also synthesized to produce patterns with photochemical reaction. After imidization, the resolution of copolymerized PSPI (co-PSPI) pattern was in the range of 16 μm–110 μm. Partial photoreactive cross-linking structure was maintained to improve the thermal stability of co-PSPI. The co-PSPI exhibited higher glass transition temperatures (327.0°C–358.8°C) than copolymerized PI (307.4°C–332.9°C). This work provides the study on the synthesis and properties of quaternary copolymerized PI and PSPI.
{"title":"Quaternary copolymerized polyimides and negative photosensitive polyimide: preparation and properties","authors":"Jiahao Wu, Shiyang Zhang, Mingwei Cai, Qingling Li, Zhi Wang, Xiaochuang Lu, Yonggang Min","doi":"10.1177/09540083231195528","DOIUrl":"https://doi.org/10.1177/09540083231195528","url":null,"abstract":"Photosensitive polyimide (PSPI) have been developed base on polyimide (PI). PSPI can be used as insulating and protective materials in the microelectronics industry due to the excellent insulating properties, thermal stability, and chemical stability. In this work, we designed a synthetic method to improve the regularity of the polymer chain segment sequence. Quaternary block copolymerized precursors were prepared using condensation polymerization of poly (acid amid). A photosensitive poly (acid amid) salts (co-PAS) was also synthesized to produce patterns with photochemical reaction. After imidization, the resolution of copolymerized PSPI (co-PSPI) pattern was in the range of 16 μm–110 μm. Partial photoreactive cross-linking structure was maintained to improve the thermal stability of co-PSPI. The co-PSPI exhibited higher glass transition temperatures (327.0°C–358.8°C) than copolymerized PI (307.4°C–332.9°C). This work provides the study on the synthesis and properties of quaternary copolymerized PI and PSPI.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45652263","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 : 2023-09-01DOI: 10.1177/09540083231199969
Junjie Zhou, Kangkang Guo, Fan Wang, Y. Zhu, H. Qi
Herein, the catalytic effects of aromatic amines with different structures on the room temperature curing of bisphenol E cyanate (BECy) have been studied using differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR) spectroscopy. Our results revealed that the mixed amine comprised of aniline and N,N-dimethyl-p-phenylenediamine (AN/NNDPA) bearing primary amino groups in its structure was a highly effective catalyst for the room temperature curing of cyanate esters. When the cyanate ester and mixed amine were combined at a molar ratio of 100:5 and cured at room temperature for 5 days, the curing degree of BECy resin reached 79.7%. The room temperature curing mechanism of the BECy-AN/NNDPA system was investigated using pyrolysis gas chromatography-mass spectrometry (PY GC-MS). Our results showed that the formation reactions of the intermediate structure and cyclotrimerization reactions occurred during the room-temperature curing process. The activation energies of BECy and different aromatic amine systems at different heating rates were determined using non-isothermal DSC. The results further demonstrated the catalytic effect of AN/NNDPA on the cyanate ester curing reaction. BECy-AN/NNDPA cured at room temperature has suitable heat resistance and a 5% weight loss temperature (Td5) of 361°C.
{"title":"Cure behavior and mechanism of cyanate ester with aromatic amines at room temperature","authors":"Junjie Zhou, Kangkang Guo, Fan Wang, Y. Zhu, H. Qi","doi":"10.1177/09540083231199969","DOIUrl":"https://doi.org/10.1177/09540083231199969","url":null,"abstract":"Herein, the catalytic effects of aromatic amines with different structures on the room temperature curing of bisphenol E cyanate (BECy) have been studied using differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR) spectroscopy. Our results revealed that the mixed amine comprised of aniline and N,N-dimethyl-p-phenylenediamine (AN/NNDPA) bearing primary amino groups in its structure was a highly effective catalyst for the room temperature curing of cyanate esters. When the cyanate ester and mixed amine were combined at a molar ratio of 100:5 and cured at room temperature for 5 days, the curing degree of BECy resin reached 79.7%. The room temperature curing mechanism of the BECy-AN/NNDPA system was investigated using pyrolysis gas chromatography-mass spectrometry (PY GC-MS). Our results showed that the formation reactions of the intermediate structure and cyclotrimerization reactions occurred during the room-temperature curing process. The activation energies of BECy and different aromatic amine systems at different heating rates were determined using non-isothermal DSC. The results further demonstrated the catalytic effect of AN/NNDPA on the cyanate ester curing reaction. BECy-AN/NNDPA cured at room temperature has suitable heat resistance and a 5% weight loss temperature (Td5) of 361°C.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42765145","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}
The synthesis of a low dielectric constant polyimide (PI) with a polyhedral oligomeric silsesquioxane (POSS) cross-linked structure is presented. A non-planar conjugated diamine monomer (FSNH2) with two -CH=CH2 reactive groups was first synthesised in a two-step process, and then two polyimides were synthesized by PSS-Octavinyl (OVPOSS) substituted, FSNH2 and dianhydride. OVPOSS cross-linked polyimides have good thermal stability and low dielectric constant. 6FDA-FSNH2-OVPOSS(6FPI-3) can reach a minimum dielectric constant of 2.08 (108 Hz) and a dielectric loss of 0.008 (108 Hz). In addition, the cross-linked structure of the OVPOSS and polyimide chains prevents the agglomeration of OVPOSS to a certain extent and improves the tensile strength and elongation at break of the polyimides, which has great application potential in large-scale integrated circuits.
{"title":"Bulk side-based polyimide based on polyhedral oligomeric silsesquioxane cross-linking: Towards lower dielectric constant and better mechanical property","authors":"Mengqiu Wang, Qianyu Song, Lishuai Zheng, Linxi Hou","doi":"10.1177/09540083231198882","DOIUrl":"https://doi.org/10.1177/09540083231198882","url":null,"abstract":"The synthesis of a low dielectric constant polyimide (PI) with a polyhedral oligomeric silsesquioxane (POSS) cross-linked structure is presented. A non-planar conjugated diamine monomer (FSNH2) with two -CH=CH2 reactive groups was first synthesised in a two-step process, and then two polyimides were synthesized by PSS-Octavinyl (OVPOSS) substituted, FSNH2 and dianhydride. OVPOSS cross-linked polyimides have good thermal stability and low dielectric constant. 6FDA-FSNH2-OVPOSS(6FPI-3) can reach a minimum dielectric constant of 2.08 (108 Hz) and a dielectric loss of 0.008 (108 Hz). In addition, the cross-linked structure of the OVPOSS and polyimide chains prevents the agglomeration of OVPOSS to a certain extent and improves the tensile strength and elongation at break of the polyimides, which has great application potential in large-scale integrated circuits.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45783834","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 : 2023-08-31DOI: 10.1177/09540083231200134
Li Ye, Luyao Wang, Xiaoyu Zhang, Yujie Liu, Xinheng Wu, Yu Zhang, Fanglei Zeng, Ning Li, Dezhi Qu, Hongyan Dai
In this study, hydroxyl-terminated carborane polyarylates were directly reacted with isocyanates by direct main chain introduction method. Three carborane polyurethane resins were prepared by using polyarylates and isocyanates. The best curing process conditions were determined through curing kinetics research and experiments. TGA, DSC, XRD and variable temperature infrared spectroscopy were used to investigate the thermal properties. The combustion performance was studied by heat release rate (HRR), total heat release (THR) and limiting oxygen index (LOI). The surface morphology after heat treatment of carborane polyurethane resin and traditional polyurethane was observed by SEM method and focused on the stability of carborane polyurethane resin.
{"title":"Preparation and characterization of carborane polyurethane with excellent high carbon residue and flame retardancy","authors":"Li Ye, Luyao Wang, Xiaoyu Zhang, Yujie Liu, Xinheng Wu, Yu Zhang, Fanglei Zeng, Ning Li, Dezhi Qu, Hongyan Dai","doi":"10.1177/09540083231200134","DOIUrl":"https://doi.org/10.1177/09540083231200134","url":null,"abstract":"In this study, hydroxyl-terminated carborane polyarylates were directly reacted with isocyanates by direct main chain introduction method. Three carborane polyurethane resins were prepared by using polyarylates and isocyanates. The best curing process conditions were determined through curing kinetics research and experiments. TGA, DSC, XRD and variable temperature infrared spectroscopy were used to investigate the thermal properties. The combustion performance was studied by heat release rate (HRR), total heat release (THR) and limiting oxygen index (LOI). The surface morphology after heat treatment of carborane polyurethane resin and traditional polyurethane was observed by SEM method and focused on the stability of carborane polyurethane resin.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135830130","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 : 2023-08-30DOI: 10.1177/09540083231199766
Yuxia Zhang, Haojie Liu, Menghan Liu, Xiaofan Ma, Haifeng Shi
The utilization of functionalized graphene oxide as nanofillers has attracted significant attention in the development of high-performance composite materials. In this study, amine-functionalized graphene oxide (AFGO) by different amines, including p-phenylenediamine- (PPD-GO) and 4, 4’-diaminodiphenyl ether (ODA-GO), respectively, was prepared and used to synthesize a series of polyimide (PI) composite membranes via in situ polymerization method. The PPD-GO/PI and ODA-GO/PI composite membranes exhibited much higher mechanical and thermal properties than that of neat PI, owing to the diverse interfacial interaction and the surface architecture behavior. Compared to neat PI, the tensile strengths were enhanced 14.6% and 14.5%, the tensile modulus were enhanced 26.9% and 23.2%, and the Tg increased by 9°C and 17.5°C of the PI composite membrane containing 0.3 wt% PPD-GO or ODA-GO, respectively. This study provides a guidance for the development of high-performance PI composite materials through the regulated interfacial structure via the moderate chain length.
{"title":"Effects of different amine-functionalized graphene oxide on the mechanical and thermal properties of polyimide composites","authors":"Yuxia Zhang, Haojie Liu, Menghan Liu, Xiaofan Ma, Haifeng Shi","doi":"10.1177/09540083231199766","DOIUrl":"https://doi.org/10.1177/09540083231199766","url":null,"abstract":"The utilization of functionalized graphene oxide as nanofillers has attracted significant attention in the development of high-performance composite materials. In this study, amine-functionalized graphene oxide (AFGO) by different amines, including p-phenylenediamine- (PPD-GO) and 4, 4’-diaminodiphenyl ether (ODA-GO), respectively, was prepared and used to synthesize a series of polyimide (PI) composite membranes via in situ polymerization method. The PPD-GO/PI and ODA-GO/PI composite membranes exhibited much higher mechanical and thermal properties than that of neat PI, owing to the diverse interfacial interaction and the surface architecture behavior. Compared to neat PI, the tensile strengths were enhanced 14.6% and 14.5%, the tensile modulus were enhanced 26.9% and 23.2%, and the Tg increased by 9°C and 17.5°C of the PI composite membrane containing 0.3 wt% PPD-GO or ODA-GO, respectively. This study provides a guidance for the development of high-performance PI composite materials through the regulated interfacial structure via the moderate chain length.","PeriodicalId":12932,"journal":{"name":"High Performance Polymers","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42062078","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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