Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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Analysis of cure behavior of low temperature curing liquid silicone rubber (LSR) for multi-material injection molding

이중사출 성형을 위한 저온 경화 액상실리콘고무 (LSR)의 경화 거동 분석

  • Hyeong-min Yoo (School of Mechanical Engineering, Korea University of Technology and Education (KOREATECH))
  • 유형민 (한국기술교육대학교 기계공학부)
  • Received : 2023.02.03
  • Accepted : 2023.03.31
  • Published : 2023.03.31
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Abstract

In multi-material injection molding, since two or more materials with different process conditions are used, it is essential to maximize process efficiency by operating the cooling or heating system to a minimum. In this study, Liquid silicone rubber (LSR) that can be cured at a low temperature suitable for the multi-material injection molding was selected and the cure behavior according to the process conditions was analyzed through differential scanning calorimetry (DSC). Dynamic measurement results of DSC with different heating rate were obtained, and through this, the total heat of reaction when the LSR was completely cured was calculated. Isothermal measurement results of DSC were derived for 60 minutes at each temperature from 80 ℃ to 110 ℃ at 10 ℃ intervals, and the final degree of cure at each temperature was calculated based on the total heat of reaction identified from the Dynamic DSC measurement results. As the result, it was found that when the temperature is lowered, the curing start time and the time required for the curing reaction increase, but at a temperature of 90 ℃ or higher, LSR can secure a degree of cure of 80% or more. However, at 80 ℃., it was found that not only had a relatively low degree of curing of about 60%, but also significantly increased the curing start time. In addition, in the case of 110 ℃, the parameters were derived from experimental result using the Kamal kinetic model.

Keywords

Acknowledgement

본 연구는 중소벤처기업부의 2022년도 중소기업 기술혁신개발사업 (과제번호 : S3269454) 지원을 받아 수행 된 연구결과 입니다.

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