이종재료 강화 하이브리드 폴리우레탄 폼의 기계적·열적 특성에 관한 연구

Abstract

Polyurethane foams have been widely used in various industrial fields such as marine shipbuilding, motor industry, refrigeration system and building materials due to their excellent thermal insulation, shock absorption, and light weight. For these reasons, the research on the improvement of mechanical strength and thermal performance in polyurethane foams have been deepened and expanded in order to apply these characteristics in various industrial conditions. In this thesis, mechanical·thermal characteristics of dissimilar materials-reinforced hybrid polyurethane foams(DMRH-PUF) were considered. Three major research topics that are presented in this thesis are as following; 폴리우레탄 폼(Polyurethane foams)은 우수한 단열 특성, 충격흡수성 및 경량성 등의 이유로 조선해양, 자동차, 냉동시스템 그리고 건축자재와 같은 다양한 산업분야에서 널리 사용되고 있다. 이에 따라 보다 다양한 환경에서 유용하게 그 특성을 발현하기 위해서 재료의 기계적 강도 향상과 함께 열적 성능에 대한 연구가 심화, 확대되고 있다. 본 논문은 이종재료 강화 하이브리드 폴리우레탄 폼(Dissimilar materials- reinforced hybrid polyurethane foams, DMRH-PUF)의 기계적·열적 특성에 관한 연구로써 첫째, 이종재료 및 그 함량이 상이한 DMRH-PUF의 제조, 둘째, DMRH-PUF의 기계적·열적 특성에 관한 이종재료의 강화 효과를 예측할 수 있는 이론적 모델 제시 및 시험을 통한 검증, 그리고 셋째, 적용재료 및 그 함량에 따른 DMRH-PUF의 기계적·열적 성능평가를 통한 최적화 등으로 구분할 수 있다. 이와 관련하여, 이론적 연구로써 DMRH-PUF의 탄성거동 모델과 열전달 모델을 제시하였으며, 단축 압축시험 및 열전도율시험을 통해 예측식과 시험결과를 비교함으로써 이론적 모델의 타당성을 확인하였다. 본 연구를 통해 DMRH-PUF의 기계적·열적 특성에 관한 이종재료 강화효과와 함께 단열특성을 이론적, 실험적으로 고찰할 수 있었다. 이에 사용 재료에 따른 적합 함량을 분석하였으며, 각각의 적용 재료가 동일 함량일 때 강화 및 단열 효과가 우수한 사양을 확인할 수 있었다.|Polyurethane foams have been widely used in various industrial fields such as marine shipbuilding, motor industry, refrigeration system and building materials due to their excellent thermal insulation, shock absorption, and light weight. For these reasons, the research on the improvement of mechanical strength and thermal performance in polyurethane foams have been deepened and expanded in order to apply these characteristics in various industrial conditions. In this thesis, mechanical·thermal characteristics of dissimilar materials-reinforced hybrid polyurethane foams(DMRH-PUF) were considered. Three major research topics that are presented in this thesis are as following; 1. Manufacturing of DMRH-PUF by applying dissimilar materials and different contents, 2. Development of theoretical models which can predict a reinforcing effect of dissimilar materials on the mechanical·thermal characteristics of DMRH-PUF, and their validation through compressive test and thermal conductivity measurement test, 3. Optimization of dissimilar materials contents by mechanical·thermal performance evaluation of DMRH-PUF depending on dissimilar materials and different contents. In this regard, elastic behavior and heat transfer models of DMRH-PUF were suggested, and theoretical models were validated by comparing the predictive values with the test results of compressive test and thermal conductivity measurement test. From the results, reinforcing and insulating effects of dissimilar materials on the mechanical·thermal characteristics of DMRH-PUF were considered theoretically and experimentally. Appropriate contents of dissimilar materials were analyzed afterward. Furthermore, DMRH-PUF with outstanding reinforcing and insulating effect were identified when each applied material was added the same contents.