Effects of Mold Temperatures on Physical Properites of Injection Molded Thermoplastic Polyurethanes

사출성형 열가소성 폴리우레탄의 물리적 성질에 미치는 금형 온도 영향

  • Lee, Dai-Soo (Division of Environmental and Chemical Engineering Chonbuk National University) ;
  • Kim, Seong-Geun (Division of Environmental and Chemical Engineering Chonbuk National University) ;
  • Nguyen, Vinh-Khanh (Division of Environmental and Chemical Engineering Chonbuk National University) ;
  • Lee, Wing-Ji (Division of Environmental and Chemical Engineering Chonbuk National University) ;
  • Pang, Su-Jin (Division of Environmental and Chemical Engineering Chonbuk National University)
  • 이대수 (전북대학교 환경화학공학부) ;
  • 김성근 (전북대학교 환경화학공학부) ;
  • 구엔빈칸 (전북대학교 환경화학공학부) ;
  • 이명걸 (전북대학교 환경화학공학부) ;
  • 방수진 (전북대학교 환경화학공학부)
  • Published : 2004.12.31

Abstract

Ester- and ether-based thermoplastic polyurethanes of different hardness were injection molded at different mold temperatures and effects of mold temperature on the physical properties of TPUs were investigated. Glass transition temperatures of soft segments of TPUs were hardly changed by mold temperatures. The phase separation of soft and hard segments of injection molded TPUs were affected little by mold temperatures. However, crystallinity of hard segments, temperature range of rubbery plateau, and tensile strength of injection molded TPUs decreased with increasing mold temperatures for TPUs of high hardness. However, injection molded TPUs of low hardness showed increases of crystallinity of hard segments, temperature range of rubbery plateau, and tensile strength with increasing mold temperatures. Different physical properties of injection molded TPUs depending on mold temperatures were attributed to different crystallization and physical crosslinking effects of hard segments.

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