新型含吡啶环氟化二胺及其共聚聚酰亚胺的合成与性能

Synthesis and properties of copolyimide derived from novel fluorinated pyridine-containing diamine

以3-羟基苯乙酮和苯甲醛为原料,通过改进的Chichibabin反应制备了4-苯基-2,6-双(3-羟基苯基)吡啶(m-PHPP),再将其与2-氯-5-硝基三氟甲苯反应,合成了硝基化合物4-苯基-2,6-双[3-(4-硝基-2-三氟甲基苯氧基)苯基]吡啶(m,p-6FPNPP),最后用Pd/C和水合肼将m,p-6FPNPP进行还原,成功制备了一种新型含吡啶环氟化的芳香二胺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)。以m,p-6FPAPP及2,2-双[4-(4-氨基苯氧基)苯基]丙烷(BAPP)作为二胺,3,3′,4,4′-二苯醚四羧酸二酐(ODPA)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,合成了一种新型的氟化含吡啶环聚酰亚胺。用TIR、DSC、TGA、XRD、溶解性测试、力学性能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,所得的聚合物在1780cm^(-1)、1720cm^(-1)和1380cm^(-1)左右出现了聚酰亚胺的特征吸收峰。制备的聚酰亚胺能很好地溶解于常见有机溶剂(如DMF、DMAC、DMSO、NMP、THF、CHCl_3),且膜有很好的热稳定性,玻璃化转变温度(T_g)为234.4℃,氮气氛中10%失重温度为575.3℃。所得聚酰亚胺膜的拉伸强度为97.3 MPa,拉伸模量为1.84GPa,吸水率为0.63%。

A novel pyridine-containing aromatic diamine monomer,4-phenyl-2,6-bis[3-（4-amino-2-trifluorom-ethyphenoxy） phenyl]pyridine（m,p-6FPAPP）,was prepared in three steps starting from a modified Chichibabin reaction of 3-hydroxyacetophenone and benzaldehyde to form 4-phenyl-2,6-bis（3-hydroxyphenyl） pyridine（m-PHPP）, followed by nucleophilic substitution reaction of m-PHPP with 2-chloro-5-nitrobenzotrifluoride in the presence of potassium carbonate gives the dinitro compound 4-phenyl-2,6-bis[3-（4-nitro-2-trifluoromethyphenoxy） phenyl]pyridine（m,p-6FPNPP）,and finally the novel diamine monomer m,p-6FPAPP obtained in a high yield by the reduction of m,p-6FPNPP using hydrazine monohydrate catalyzed by Pd/C.A novel fluorinated poly（pyridineimide） was synthesized via the conventional two-step method by using m,p-6FPAPP and 2,2-bis[4-（4-aminophe-noxy） phenyl]propane（BAPP） as the diamine monomers,4,4＇-Oxydiphthalic dianhydride（ODPA） as the dianhydride monomer in dimethylformamide（DMF）.The structure and performance of polymer were characterized by FTIR,solubility testing,XRD,DSC,TGA,tensile tests and water uptake testing.The results showed that there are characteristic peaks of polyimide around 1 780 cm^（-1）,1 720 cm^（-1） and 1 380 cm^（-1） in the FTIR spectrum.The polyimide was soluble in common organic solvents such as m-Cresol,DMF,DM Ac,DMSO,NMP,THF,CHCl_3.The PI films had good thermal stability with glass transition temperature of 234.4℃and initial decomposition temperature in nitrogen atmosphere 575.3℃in nitrogen atmosphere.The tensile strength,tensile modulus,and water uptake of the PI film was 97.3 MPa,1.84 GPa and 0.63%,respectively.