Fabrications and Properties of Colorless Polyimide Films Depending on Various Heat Treatment Conditions via Crosslinkable Monomer
Choi IH, Chang JH
가교 가능한 단량체를 이용한 무색투명 폴리이미드 필름 제조와 다양한 열처리에 따른 성질
최일환, 장진해
Abstract
Poly(amic acid)(PAA) was prepared by reaction of bicyclo(2,2,2)oct-7-ene-2,3,5,6-tetracarboxylicdianhydride(BTDA) containing double bond for crosslinking and bis[4-(3-aminophenoxy) phenyl] sulfone(BAPS) in N,N-dimethylacetamide(DMAc). The cast film of PAA was heat-treated at different temperatures to create polyimide(PI) films. With increasing thermal crosslinking temperatures from 250 to 350 ℃, the thermo-mechanical properties, degree of crosslinking, and optical transparency of the cross-linked PI were investigated. The maximum enhancement in the thermo-mechanical properties was observed at a heat treatment condition of 350 ℃. However, the optical transparency was found to be optimal for 250 ℃ heat treatment. The degree of crosslinking in NMR was determined to be 85% to 93% with increasing annealing temperature conditions from 250 to 350 ℃.
폴리아믹산(PAA)은 가교가 가능한 2중 결합을 갖는 bicyclo(2,2,2)oct-7-ene-2,3,5,6-tetracarboxylicdianhydride(BTDA)와 bis[4-(3-aminophenoxy)phenyl] sulfone(BAPS)을 N,N-dimethylacetamide(DMAc) 용매에서 반응하여 얻어졌으며, 폴리이미드(PI) 필름은 PAA를 캐스팅하여 각각 다른 반응 온도에서 열처리를 통해 얻었다. 가교 온도를 250∼350 ℃까지 증가하여 얻은 가교된 PI의 열적-기계적 성질, 가교도, 광학적 특성을 열처리 온도에 따라 조사하였다. 열적-기계적 성질은 350 ℃에서 열처리되었을 때 최대 값을 나타냈으며, 광학적 특성은 250 ℃에서 열처리된 필름이 가장 우수한 광학특성을 보였다. 250∼350 ℃까지 열처리에 따른 가교도는 NMR 상에서 85∼93%를 나타냈다.