The relationships among mechanical properties, rheological properties, and morphology by reactive extrusion based on commingled pckaging film wastes containg polypropylene (PP) pckaging film system [PP/polyethylene (PE)/aluminum (Al)poly(ethylene terephthalate) (PET)] and Nylon packaging film system[Nylon/PE/linear-low density polyethylene (LLDPE)] were investigated to improve the compatibility and toughness of these wastes using various compatibilizers such as ethylene vinylacetate (EVA), styrene-ethylene/butylene-styrene triblock copolymer (SEBS), styrene-ethylene/butylene-styrene-graft-maleic anhydride copolymer (SEBS-g-MA), polyethylene-graft-maleic anhydride (PE-g-MA), polypropylene-graft-maleic anhydride (PP-g-MA), polyethylene-graft-acrylic acid (PE-g-AA) and polypropylene-graft-acrylic acid (PP-g-AA). Compared with simple melt blend system, the blends showed improvement of about 50% increase in physical properties when SEBS and EVA were added. However, SEBS-g-MA thermoplastic elastomer which is highly reactive with amine terminal group of nylon, resulted in about 200% increase in impact strength. This compatibilization effect resulted from the increase of interfacial adhesion and the reduction of domain size of dispersed phase in PP/Nylon blend system.
포장용 필름 등으로 사용되는 폴리프로필렌(PP)계 필름[PP/polyethylene(PE)/aluminum(Al)/poly(ethylene terephthalate)(PET)]과 나일론(Nylon)계 필름[Nylon/PE/linear-low density polyethylene(LLDPE)] 등 혼합 폐포장 필름의 상용성 증진과 강인화를 위해 시판되는 여러 가지 상요화제 중 ethylene vinylacetate(EVA), styrene-ethylene/butylene-styrene triblock copolymer(SEBS), styrene-ethylene/butylene-styrene-graft-maleic anhydride copolymer(SEBS-g-MA), polyethylene-graft-maleic anhydride(PE-g-MA), polypropylene-graft-maleic anhydride copolymer(SEBS-g-MA), polyethylene-graft-maleic anhydride(PE-g-MA), polypropylene-graft-maleic anhydride(PP-g-MA), polyethylene-graft-acrylic acid(PE-g-AA), poly-propylene-graft-acrylic acid(PP-g-AA) 등을 사용하여 반응 압출 공정에 의한 기계적 물성, 유성학적 성질과 형태학적 변화를 살펴보았다. 단순 응용 블렌드와 비교하여 상용화제로 SEBS와 EVA를 사용하였을 때 약 50%의 물성 향상을 보였으나 나일론의 말단기인 아민기와의 반응성 향상을 위해 무수말레인산이 그래프트된 열가소성 탄성체 SEBS-g-MA의 사용시 분산 입자의 감소 및 접촉면적의 증가에 의한 계면 접착력의 증가로 약 200% 이상의 내충격성이 향상을 이룰 수 있었다.
Keywords: reactive compatibilizer; reactive extrusion; commingled pckaging film; compatibility; toughness