| Summary: | 碩士 === 中原大學 === 化學工程研究所 === 93 === The objective of this work is to prepare porous or hollow polyimide particle. Submicron monodisperse poly(amic acid) particles prepared by using precipitation polycondensation were have been used as seeds. Diluents (water, acetic anhydride, aetonitrile) was added to swell seeds. Subsequently, porous or hollow polyimide was formed by chemical imidization with adding acetic anhydride as dehydration agent or by thermal imidization. The main objectives of this study are: (1) to investigate the effect of the kind and amount of diluents on the surface and interior morphology on the polymer particles, and expect to understand the mechanism of porous or hollow particle formation. (2) to investigate the effects of kind of the imidization on morphology formation of the polyimide particles.
From the experimental results, porous poly(amic acid) particle can be prepared by using water as diluent. When acetic anhydride or acetonitrile as the diluent, respectively, the multihollow particles turn into hollow particle with increasing the amount of diluent. In order to clarify the multihollow or hollow structure in detail, the evaporation behavior of toluene of solid particles and multihollow or hollow particles is investigate. Thermal imidization can destroy the structure of porous or hollow particles. Chemical imidization can retain the structure of porous or hollow polyimide particles, but the degree of imidization and thermal property of polyimide is poor than those of thermal imidization.
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