摘要
以4-硝基苯乙胺盐酸盐与二(对硝基苯)碳酸酯为原料,合成了一种含脲键半脂肪族二胺单体N,N'-双(4-氨基苯乙基)脲(BAPU),将其与4,4'-二氨基二苯醚(ODA)和双酚A型二醚二酐(BPADA),按不同n(BAPU)∶n(ODA),采用两步化学亚胺化法,制备了6种脲键和亚乙基相对含量不同的聚酰亚胺(PI),进一步制备成PI薄膜。采用^(1)HNMR和FTIR、XRD对中间体及PI结构进行了表征。通过乌氏黏度计、接触角测定仪、TGA、DMA、DSC、UV-Vis、材料万能试验机、矢量网络分析仪对PI薄膜的特性黏数、表面能、热性能、光透射性、力学性能、介电性能进行了测试。结果表明,制备的系列PI特性黏数在0.70~1.64 dL/g,系列PI薄膜的表面能在31.7~50.0 mJ/m^(2),50 mg PI在室温下可以完全溶解于体积均为1 mL的N,N-二甲基乙酰胺、N-甲基吡咯烷酮或间甲酚中;PI薄膜在450和500 nm处的透过率分别为61%~81%和75%~83%,截止波长为362~384 nm,表现出良好的光透射性;DSC测得PI的玻璃化转变温度为164~221℃,N_(2)氛围下热失重5%时的温度为339~550℃;PI薄膜的拉伸强度为57.3~84.7 MPa,杨氏模量为1.7~2.9 GPa,断裂伸长率为5.0%~8.8%,具有较好的力学性能;PI薄膜的相对介电常数为3.11~3.31,吸水率为0.84%~1.26%。
A urea-bonded semi-aliphatic diamine monomer,N,N'-bis(4-aminophenethyl)urea(BAPU),was synthesized from 4-nitrophenylethylamine hydrochloride and bis(p-nitrophenyl)carbonate.Six polyimides(PI)with varying urea bond contents and ethylidene structures were then prepared via a two-step chemical imidization method,using BAPU,4,4'-diaminodiphenyl ether(ODA),and bisphenol A-type diphenyl ether dianhydride(BPADA)as raw materials,with different molar ratios of BAPU to ODA,and further processed into films.The structures of the intermediates and PI samples were characterized by¹HNMR,FTIR,and XRD.The intrinsic viscosities,surface energy,thermal properties,optical transmittance,mechanical properties and dielectric properties of these PI films were characterized via Ubbelohde viscometer,contact angle goniometer,TGA,DMA,DSC,UV-Vis,universal testing machine,and vector network analyzer.The results showed that the intrinsic viscosities of the PI samples ranged from 0.70 dL/g to 1.64 dL/g.The surface energy of the PI films was between 31.7 and 50.0 mJ/m^(2).Moreover,50 mg of the PI samples could be completely dissolved in 1 mL of N,N-dimethylacetamide,N-methyl-2-pyrrolidinone,or m-cresol at room temperature.The transmittance of PI films at 450 nm and 500 nm was 61%~81%and 75%~83%,respectively,with the cutoff wavelength ranging from 362 nm to 384 nm.These optical characteristics indicated excellent light transmission performance.The glass transition temperature tested by DSC and 5%thermal weight loss temperature of PI samples were 164~221 and 339~550℃,respectively.The tensile strength,Young's modulus and elongation at break of PI films were 57.3~84.7 MPa,1.7~2.9 GPa and 5.0%~8.8%,respectively,indicating excellent mechanical properties.The dielectric constant of PI films was 3.11~3.31,with a moisture absorption rate ranging from 0.84%to 1.26%.
作者
张俸斌
乔文强
王植源
ZHANG Fengbin;QIAO Wenqiang;WANG Zhiyuan(State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China)
出处
《精细化工》
北大核心
2026年第3期532-539,554,共9页
Fine Chemicals
关键词
聚酰亚胺
表面能
光透射性
脲键
亚乙基
功能材料
polyimides
surface energy
optical transmittance
urea bonds
ethylidene
functional materials
