【作者】 宋宁；

【导师】 陈建定； 倪礼忠；

【作者基本信息】 华东理工大学 ， 材料学， 2012， 博士

【摘要】 芳基乙炔树脂与传统的热固性树脂相比具有成型工艺性能好、固化过程中无挥发物生成、高温烧蚀后质量保留率高等特点,在航空航天等高科技领域广泛应用。在芳炔树脂中引入硅、硼、氮、磷等无机元素,可以有效提高材料的耐高温性能和耐热氧化性能。本文通过简单易行的方法得到了几种不同结构的含硅、氮、硼元素的芳炔树脂,此类树脂结构中都含有乙炔基,在受热条件下通过乙炔基的交联反应而固化成型,此类材料可用作耐高温结构部件、陶瓷前驱体及复合材料基体材料。本文以其中两种树脂作为树脂基体制备了新型的玻璃纤维增强树脂基复合材料,对复合材料的力学性能、介电性能、耐高温性能和耐湿性能进行研究,以满足航空航天领域对耐高温复合材料的需求。本文对以下三方面内容进行研究：第一,采用氯硅烷与间氨基苯乙炔的胺解反应制备了五种结构的乙炔基苯胺硅烷(EAS)：甲基-二(间乙炔基苯胺)硅烷(MEAS)、二甲基-二(间乙炔基苯胺)硅烷(DMEAS).甲基-三(间乙炔基苯胺)硅烷(MTEAS)、苯基-三(间乙炔基苯胺)硅烷(PTEAS)及四(间乙炔基苯胺)硅烷(TEAS)。采用IR、MS、1H-NMR,13C-NMR对其结构进行了表征。利用分子结构中端乙炔基的高活性,EAS可以在较低的温度下发生固化反应,有利于其成型及应用。对乙炔基苯胺硅烷的固化反应动力学和固化反应机理进行了研究。用TGA法研究了乙炔基苯胺硅烷的热稳定性以及结构对固化物耐热性的影响,结果表明分子结构中乙炔基数量越多,固化物交联密度越高,固化物的耐高温性能越好。氮气下,TEAS固化物的Td5为607℃,在900℃下的质量保留率为86.0%,但乙炔基苯胺硅烷固化物高温下对氧敏感,耐热氧化性能有待提高。MEAS固化物在1450℃下高温陶瓷化后有无定形碳、β-SiC和α-Si3N4生成。采用分子结构中含苯乙炔基团的(N-间乙炔基苯基邻苯二甲酰亚胺)醚(DAIE)树脂对TEAS树脂改性,制备了玻璃纤维增强树脂基复合材料。TEAS和DAIE树脂质量比为5：3时,固化反应温度最低,成型工艺性能和力学性能最佳。TEAS/DAIE基复合材料具有优良的力学性能和耐高温性能,弯曲强度和层间剪切强度分别为385.7MPa和37.5MPa,400℃下高温处理20min后质量保留率和弯曲强度保留率为96.7%和91.0%。第二,镍粉催化下甲基二苯乙炔基硅烷(MDPES)和苯硼酸发生脱除氢气反应,制备得到了新型树脂：苯基二[(甲基二苯乙炔基)硅-氧]硼烷(B-MDPES)。在分子结构中引入Si-O-B结构,有效提高了固化物的耐高温性能和热氧化性能,通过消除MDPES结构中的硅氢键,解决树脂基复合材料制备过程中由于脱除氢气而发泡的问题。B-MDPES固化物在氮气和空气下的Td5分别为681.4℃和578.4℃,900℃下的质量保留率分别为91.7%和42.6%,在空气下温度高于580℃对氧敏感。采用热裂解-气质联用法研究了B-MDPES固化物于氩气气氛中750℃下的热裂解产物主要为苯、联苯、苯基萘等,其中苯含量高达49.27%。采用DAIE改性B-MDPES树脂体系作为树脂基体制备了复合材料,对复合材料的力学性能、介电性能、耐高温性能和耐湿性能进行了研究。第三,采用苯硼酸与苯基三氯硅烷、苯乙炔基锂反应,得到了重复单元中含有苯乙炔基和Si-O-B基团的聚合物-聚苯乙炔基硅氧硼烷(PSOB);通过氯铂酸催化硼酸和二苯基二氯硅烷反应,得到的含硅氧硼基团的氯化物与苯乙炔基锂反应,得到三(二苯基苯乙炔硅氧)-硼烷(TSOB)。采用红外光谱、1H-NMR、13C-NMR、29Si-NMR、11B-NMR对PSOB和TSOB分子结构进行了表征。PSOB固化物具有优异的耐热氧化性能,在氮气和空气下的Td5为573℃和565℃,在900℃下的质量保留率为87.6%和65.0%。采用热裂解-气质联用法研究了PSOB固化物于氩气气氛中750℃下的热裂解产物及其含量,热裂解产物主要为苯、联苯、苯基萘、蒽等,其中含量最高的是苯,占77.1%。PSOB和TSOB固化物陶瓷化率分别为47.6%和49.7%,远高于苯基三苯乙炔基硅烷固化物的陶瓷化率(20.1%),说明硼元素的引入有利于材料的陶瓷化反应。更多还原

【Abstract】 Aryl-acetylene resins possess the characteristics of ease of processing, no volatility during cure and high residue after pyrolysis, compared with current thermosetting resins, which are widely used in the field of aviation. Introduction of silicon, boron, nitrogen, germanium and phosphorus into arylacetylene could improve the high-temperature resistance and thermo-oxidative stability of materials. In this article, several aryl-acetylenes containing silicon, nitrogen, boron were prepared by easy-operating synthesis reactions. These polymers obtained contained aryl-acetylene group in their structures, which could be cured and molded by means of the cross-linking reactions among arylacetylene groups. These polymers have potential of high-temperature resistant structure parts, ceramic precursors and matrix materials of composites. In this paper, composites were compared based on two resins and properties of mechanical, dielectric, resistance to high-temperature and moisture of composites were studied to meet the requirements of the field of aviation for high-temperature resistant materials.Firstly, five kinds of (ethynylphenyl-amino)silane (EAS):methly-di(m-ethynylphenyl-amino)silane (MEAS), dimethly-di(m-ethynylphenyl-amino)silane (DMEAS), methly-tri(m-ethynylphenyl-amino)silane(MTEAS), phenyl-tri(m-ethynylphenyl-amino)silane (PTEAS) and tetra(m-ethynylphenyl-amino)silane (TEAS), were prepared by the aminolysis reaction between chlorosilanes and m-aminophenylacetylene. The resulting resins were characterized by IR, MS,1H-NMR, and 13C-NMR. Due to the high activity of terminal acetylene groups in the molecule, EAS occurs cross-linking reactions at lower temperatures, which was benefit to its forming process and application. In this article, the curing reaction kinetics and the curing mechanism of EAS were studied. The high-temperature resistance and sintered properties were studied using TGA. The results showed that EAS thermosets possessed excellent high-temperature resistance. Td5 of TEAS thermoset in nitrogen was 607℃and the weight residual at 900℃was 86.0%. After sintered at 1450℃in argon, MEAS thermoset derived free carbon, (3-SiC andα-Si3N4. TEAS was modified by di (N-m-acetylene-phenylphthalimide) ether (DAIE) which containing acetylene groups in the molecule to prepare glass fiber reinforced polymer composites. The obtained composites possessed lower curing temperatures, good processing and mechanical properties when the weight ratio of TEAS to DAIE was 5:3. Flexural strength and interlaminar shear strength of the composites were 385.7 MPa and 37.5 MPa respectively.Secondly, making use of the reactivity of the Si-H bond with B-OH groups with nickel power as the catalyzer. phenyldi[(methyldiphenylethynyl)-silcon-oxygen]borane(B-MDPES) resin was prepared based on MDPES and phenylboronic acid. Si-O-B unit was intruduced successfully into the molecular structure of silicon-containing arylacetylene polymers. In this article, we studied the curing mechanisms of B-MDPES resin and the heat resistance and thermo-oxidation properties of B-MDPES thermoset. The purpose of this research was to develop boron-containing arylacetylene polymers with improved heat resistance and thermo oxidation properties. TGA data showed that B-MDPES thermoset possessed outstanding high-temperature resistance in nitrogen and was sensitive to oxygen when heated to a temperature higher than 580℃. Td5 in nitrogen and air were 681.4℃and 578.4℃. the char yields at 900℃were of 91.7% and 42.6% in nitrogen and air respectively, higher clearly than that of MDPES thermoset. The thermal decomposition processes of B-MDPES thermoset in inert atmosphere were detected using Pyrolysis-Gas Chromatography-Mass. Benzene was the main degradated compound, accounting for 49.27%. Composite was compared based on B-MDPES modified with DAIE and properties of mechanical, dielectric, resistance to high-temperature and moisture of composites were studied.Thirdly, based on phenylboronic acid, phenyltrichlorosilane, the lithium phenylacetylide poly (phenylethynylsilyl-oxide-borane) (PSOB) was prepared with Si-O-B and ph-C=C-groups contained in repeated units. Tri[diphenylphenylethynylsilyl-oxide]-borane (TSOB) was prepared based on diphenyl-dichlorosilane, boric acid, phenyl-acetylene and n-butyl lithium. The resulting products were characterized by IR,’H-NMR,13C-NMR,29Si-NMR and 11B-NMR. The temperatures of 5% weight loss (Tds) of PSOB thermoset in nitrogen and air were 573℃and 565℃, the char yields at 900℃were of 87.6% and 65.0% in nitrogen and air respectively. The decomposition process of PSOB thermoset at 750℃in argon was detected using pyrolysis-GC-MS. The results showed that benzene was the main degradated product with the content of 77.1%. The weight residual yields of PSOB and TSOB thermoset after ceramic treatment at 1450℃were 47.6% and 49.7% respectively, which were higher than that of PTPES thermoset (20.1%), which showed that the introduction of boron element was benefit to the ceramic reaction of materials.更多还原