含氟-吡啶环聚酰亚胺的合成与性能

用4-苯基-2,6-双[3-(4-氨基-2-三氟甲基苯氧基)苯基]吡啶(m,p-6FPAPP)作为二胺,3,3′,4,4′-二苯酮四甲酸二酐(BTDA)及2,2-双[4-(3,4-二羧基苯氧基)苯基]丙烷二酐(BPADA)作为二酐,以N,N-二甲基甲酰胺(DMF)为溶剂,通过常规的两步法,合成了可溶性含氟聚酰亚胺。用FT-IR、DSC、TGA、UV-vis、溶解性和吸水率测试对聚合物的结构和性能进行了表征。结果表明,FT-IR测试在1780 cm-1、1720 cm-1和1380 cm-1左右出现了聚酰亚胺的特征吸收峰。所得聚酰亚胺在常见溶剂(如间甲酚,DMF,N,N-二甲基乙酰胺(DMAc),二甲基亚砜(DMSO),N-甲基吡咯烷酮(NMP),四氢呋喃(THF))中可溶解;在氮气氛中,玻璃化转变温度(Tg)为202.1℃~219.7℃,10%失重温度为537.0℃~572.8℃,800℃质量保持率为60.7%~63.1%。PI膜的紫外截止波长为375 nm~380 nm,吸水率为0.55%~0.63%。

Synthesis and Properties of Fluorinated Pyridine-Containing Polyimides

Soluble fluorinated polyimides were synthesized via the conventional two-step method by using 4-phenyl-2,6-bis[3-(4-amino-2-trifluoromethyphenoxy)phenyl]pyridine(m,p-6FPAPP) as the diamine monomer,2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride(BPADA) and 3,3′,4,4′-biphenyltetracarboxylic dianhydride(BTDA) as the dianhydride monomers in dimethylformamide(DMF).The structure and performance of polymer were characterized by FT-IR,water uptake testing,solubility testing,DSC,TGA and UV-vis.The results show that there are characteristic peaks of polyimides around 1780 cm-1,1720 cm-1 and 1380 cm-1 in FT-IR spectra.The polyimides are soluble in common organic solvents such as m-cresol,DMF,dimethylacetamide(DMAc),dimethyl sulfoxide(DMSO),(1-methyl-2-pyrrolidone) NMP,tetrahydrofuran(THF).They have good thermal stability,with the glass transition temperature(Tg) of 202.1 ℃～219.7 ℃.Besides,their temperature at 10% mass loss is in the range of 537.0 ℃～572.8 ℃,while the weight maintenance rate of samples in 800 ℃ is 60.7%～63.1% in nitrogen atmosphere.The PI films are also found to possess the cut-off wavelengths of 375 nm～380 nm and water uptake of 0.55%～0.63%.