초록: Trimellitic anhydride chloride와 1,4-butanediol을 이용하여 1,2,4-benzenetricarboxylic acid 1,4-anhydride butylene ester(BCAB)를 새롭게 합성하였다. 합성된 BCAB와 6가지의 서로 다른 디아민(diamine)들을 이용하여 전 구체 poly(amic acid)(PAA)를 합성한 후, 열적 이미드화 반응을 통해 에스터 구조를 가지는 폴리에스터이미드(poly (ester imide), PEsI) 필름을 얻었다. 디아민 중 2,2'-bis(trifluoromethyl) benzidine(TFB)를 이용하여 합성된 PEsI와 다 양한 함량의 폴리(에틸렌 테레프탈레이트)(poly(ethylene terephthalate) PET
A series of polyimides (PIs) was synthesized by reacting a nitrile-containing aromatic diamine, 3,5-diaminobenzonitrile, with various dianhydrides to yield poly(amic acid)s that were then cyclized to yield PIs by a thermal imidization method. The samples were characterized using thermal analysis, tensile testing, optical transparency analysis, and gas permeability analysis. The cast films exhibited good thermal stability with glass transition temperatures of 204–243°C and none exhibited significant decomposition at temperatures below 480°C. These PI films showed coefficient of thermal expansion values in the range 41.68–106.16 ppm/°C. The oxygen transmission rate values of the films containing various dianhydride monomers were in the range 0.93–27.40 cc m−2 day−1. The PI films containing various dianhydride monomers showed tensile strengths of 47–128 MPa, initial moduli of 2.16–3.23, and elongations at break of 1–7%. Moreover, the PI films possessed a transmittance of 58–82% at 500 nm and had a yellowish color with a yellow index of 12.17–59.61.
Polyurethane/poly(vinyl ester resin)(butyl methacrylate) Interpenetrating Polymer Network (PU/VER(BMA) IPN) materials were synthesised at room temperature by polymerising butyl methacrylate as a comonomer with simultaneous interpenetration. The curing process of these IPNs was dynamically traced and semi-quantitatively analysed by Fourier transform infrared spectroscopy (FT-IR) and the kinetics of their formation with different PU catalysts and VER initiators was studied. The results showed that when the amounts of stannous octoate and BPO respectively were 0.5wt.% of PU and 0.67wt.% of VER, the reaction rates of the monomers were close, the conversions of the monomers were high and these amounts were optimised. The influence of the kinetics on the microstructure and damping properties of the IPNs was detected by Transmission Electron Microscopy (TEM) and by Dynamic Mechanical Analysis (DMA). The results showed that with the appropriate amount of the polyurethane catalyst stannous octoate and VER initiator BPO, the PU/VER(BMA) IPN showed a multiphase microstructure containing some finer phase domains having nanometre domain sizes, together with good damping properties (a broad damping plateau and high tanδ). When the amount of stannous octoate or BPO was increased or decreased, the IPNs presented an unfavourable microstructure and poor damping properties. The relationship between the kinetics, microstructure and damping properties was analysed further.
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