CAJ | 학술논문

以2，2′，3，3′–三苯二醚四甲酸二酐(3，3′–HQDPA)、3，3′，4，4′–三苯二醚四甲酸二酐(4，4′–HQDPA)为二酐单体，邻苯二甲酸酐为封端剂，与4，4′–二氨基二苯醚(4，4′–ODA)进行无规共聚。通过改变二酐的比例，用两步法制备了一系列热塑性共聚酰亚胺粉料，并对其热性能、溶解性能、熔体性能等进行了表征，与均聚酰亚胺进行了比较。结果表明，聚合物均具有良好的热稳定性，热分解5%的温度在空气中为500～521℃，在氮气中为507～538℃；随着3，3′–HQDPA含量的增加，玻璃化转变温度(Tg)由223℃升高至257℃，溶解性也逐渐提高。与均聚物相比，共聚物的熔体流动性有了显著地提高。可以通过调控异构二酐的比例来调控共聚酰亚胺的Tg、溶解性和熔体流动性，满足材料在不同应用上的要求，当二酐的比例为1∶1时，共聚酰亚胺的熔体流动性最好，可作为高性能、易加工的热塑性工程塑料使用。
이2，2′，3，3′–삼분이미사갑산이항(3，3′–HQDPA)、3，3′，4，4′–삼분이미사갑산이항(4，4′–HQDPA)위이항단체，린분이갑산항위봉단제，여4，4′–이안기이분미(4，4′–ODA)진행무규공취。통과개변이항적비례，용량보법제비료일계렬열소성공취선아알분료，병대기열성능、용해성능、용체성능등진행료표정，여균취선아알진행료비교。결과표명，취합물균구유량호적열은정성，열분해5%적온도재공기중위500～521℃，재담기중위507～538℃；수착3，3′–HQDPA함량적증가，파리화전변온도(Tg)유223℃승고지257℃，용해성야축점제고。여균취물상비，공취물적용체류동성유료현저지제고。가이통과조공이구이항적비례래조공공취선아알적Tg、용해성화용체류동성，만족재료재불동응용상적요구，당이항적비례위1∶1시，공취선아알적용체류동성최호，가작위고성능、역가공적열소성공정소료사용。
A series of polyimides (PI) were prepared from 3,3′,4,4′–hydroquinone diphthalic dianhydride(4,4′–HQDPA), 2, 2′,3,3′–hydroquinone diphthalic dianhydride (3,3′–HQDPA) with different ratios of the isomers and 4,4′–oxydianiline (4,4’–ODA) by the conventional two-step method. Solubility, thermal properties and melt processability of the copolyimides were investigated and compared with corresponding homopolyimides. The results show that all the polyimides exhibite excellent thermal stabilities with the 5% weight loss temperatures (Td5%) of 500~521℃ in air and 507~538℃ in nitrogen respectively. With the increasing of 3,3′–HQDPA,the polymers exhibite a regular increase in solubility and glass transition temperatures (Tg), andTg increase from 223 to 257℃. The melt processability is found to be dependent on the ratios of dianhydride units,Tg,solubility and melt flowability of copolyimides could be adjusted by the mole ratio of the isomers,so that the copolyimides could satisfy different applications. The copolyimides show better melt fluidity than the homopolyimides,and the copolyimide exhibite the best melt flowability when the mole ratio of 3,3′–HQDPA and 4,4′–HQDPA is 1∶1,which could be used as high performance melt–processable polyimides.