유변학적 및 분광학적 분석을 통한 차량 내장재용 열경화성 폴리우레탄 코팅의 열적 노화거동 연구

Abstract

Polyurethanes (PU) have elastic, low weights, chemical resistance, and good mechanical properties. So, PU has been used widely such as coatings, adhesives, insulators, foams, etc. Thermoplastic and thermosetting PU coatings are applied to the surface of the automobile. PU coating properties are affected by temperature and time. We studied the optimal temperature and time of curing PU. The best temperature and time were determined by FT-IR, UTM, and DMA. As a result of the experiment, it was revealed that 80 and 30 minutes were the best conditions for curing. In addition, PU aging at high temperatures and in UV environments. Aging occurs degradation of mechanical properties and chemical structures according to temperature and time. Herein, we study the aging of PU coatings in the different aging temperature ranges. Dynamic mechanical analysis indicated the relationship between the thermal aging of PU and glass transition temperature (Tg) of hard segment HS (Hard segment). FT-IR and TGA presented criteria for the difference between chemical and physical degradation.