端炔基遥爪型聚酰亚胺(API)的制备及T300碳纤维布/API复合材料性能

Preparation of alkynyl terminated telechelic polyimides (API) and properties of T300 carbon fiber cloth/API composites

以3,4’-氧双邻苯二甲酸酐、1,3-双(氨丙烷基)四甲基二硅醚和间氨基苯乙炔或对氨基苯基炔丙基醚为原料,合成了六种端炔基遥爪型聚酰亚胺(API),采用模压成型制备了T300碳纤维布增强API(T300碳布/API)复合材料。利用FTIR、1H NMR、DSC、TGA、DMA等方法研究了API树脂及T300碳布/API复合材料的结构和性能。结果表明,六种API树脂溶解性良好,其加工窗口随分子量的增加而变宽,端炔丙氧基API(API-e)树脂的加工性能优于端乙炔基API(API-a)树脂;API树脂固化物的热稳定性随分子量的增加而降低,API-a树脂固化物5%热失重温度(Td5)和800℃残留率高于API-e固化物,分别为473.7℃和48.8%;T300碳布/API复合材料的玻璃化转变温度可达220℃以上,其力学性能随其分子量的增加而提高,T300碳布/API-e复合材料在室温和200℃的力学性能均优于T300碳布/API-a复合材料。室温下T300碳布/API-e复合材料的弯曲强度为636.5 MPa,拉伸强度为406.1 MPa,层间剪切强度(ILSS)为48.4 MPa,在200℃的弯曲强度和ILSS分别为381.9 MPa和33.9 MPa。

Six types of telechelic polyimides with terminal alkynyl groups(API)were prepared from 3,4’-oxydiphthalic anhydride,1,3-bis(aminopropyl)tetramethyldisiloxane and m-amino phenylacetylene or p-aminophenyl propargyl ether.The T300 carbon fiber cloth(T300 cloth)reinforced API(T300 cloth/API)composites were also prepared by hot press molding.The structure and properties of the API resins and the T300 cloth/API composites were studied by FTIR,1H NMR,DSC,TGA,DMA and other methods.The results show that the six API resins have good solubility and good processability.The processing window of six API resins becomes wider as the molecular weight of the API resins increases.The processability of the API resins with terminal propargyloxy groups(API-e)is better than that of the API resins with terminal ethynyl groups(API-a).The thermal stability of the cured API resins decreases with the increasing of molecular weight.The temperature at 5%mass loss(Td5)and residual yield at 800℃of the cured API-a resins are higher than that of the cured API-e resins,which are 473.7℃and 48.8%,respectively.The glass transition temperature(Tg)of the T300 cloth/API composites can reach up to 220℃.The mechanical properties of T300 cloth/API composites increase with the increase of the molecular weight of API matrices.And the T300 cloth/API-e composites have better mechanical properties than the T300 cloth/API-a composites at room temperature and 200℃.The flexural strength,tensile strength and interlayer shear strength(ILSS)of the T300 cloth/API-e composites are 636.5 MPa,406.1 MPa and 48.4 MPa at room temperature,respectively.The flexural strength and ILSS of T300 cloth/API-e composites at 200℃are 381.9 MPa and 33.9 MPa,respectively.