Recycling of polyvinyl chloride (PVC): production and characterization of PVC foams

Öz

Plastics have been used in many areas of our daily lives for years generating large amount of post-consumption wastes. It is important to recycle and reuse of these materials since they remain without degrading for many years causing harm to the environment. Thermoplastic foams are widely used as thermal insulation, automotive seating, packaging, furniture and energy absorbing materials due to their low density, high strength/weight ratio, high energy absorption performance and superior insulation properties. In this study, potential usage of polyvinyl chloride (PVC), one of the most used plastics, in the manufacture of PVC foams were aimed. For this purpose, thermoplastic foam materials were produced by using waste PVC obtained from door and window profile wastes. The effect of chemical foaming agent amount on the some physical, mechanical and morphology properties of PVC foams were investigated. According to the obtained results, the use of foaming agent provided up to 40% reduction in the density of PVC foams. With chemical foaming agent amount were increased specific impact strength values of PVC foams. Cell structure of foams was also investigated and an increase in cell coalescence with the increase of chemical foaming agents was observed.

Anahtar Kelimeler

• Waste polyvinyl chloride
• thermoplastic foam
• chemical foaming agent
• impact strength

Polivinil klorür (PVC)’ün geri dönüştürülmesi: PVC köpük üretimi ve Karakterizasyonu

Öz

Plastikler hayatımızın birçok alanında yıllardır kullanılmakta olup kullanım ömrü sonunda önemli miktarda atık oluşturmaktadır. Doğada uzun yıllar bozunmadan kalan ve çevreye zarar veren bu malzemelerin geri dönüştürülüp tekrar kullanıma kazandırılması önem taşımaktadır. Termoplastik köpük malzemeler düşük yoğunluk, yüksek spesifik mukavemet, yüksek enerji absorblama özellikleri ve üstün yalıtım özelliklerinden dolayı ısı yalıtımı, otomotiv koltukları, ambalaj malzemeleri ve enerji absorblayıcı (soğurucu) malzemeler olarak yaygın bir şekilde kullanılmaktadır. Bu çalışmada, en çok kullanılan plastiklerden biri olan ve önemli miktarda atık oluşturan polivinil klorür (PVC)’ün geri dönüşüm yoluyla termoplastik köpük malzemelerin üretiminde kullanımı amaçlanmıştır. Bu amaçla kapı ve pencere profil atıklarından elde edilen atık PVC kullanılarak termoplastik köpük malzemeler üretilmiştir. PVC köpük malzemelerin bazı fiziksel, mekanik ve morfolojik özellikleri üzerine kimyasal köpük oluşturucu miktarının etkisi incelenmiştir. Üretilen PVC köpük malzemelerde kimyasal köpük oluşturucu malzeme miktarının artması ile PVC köpüklerin yoğunluk değerlerinde %40’lara kadar bir azalma sağlanmıştır. PVC köpüklerin spesifik darbe direnci değerleri kimyasal köpük oluşturucu miktarı ile doğrusal bir şekilde artış göstermiştir. Köpüklerin hücre yapısı incelendiğinde ise kimyasal köpük oluşturucu miktarının artması ile hücre birleşmelerinin meydana geldiği ve daha büyük hücrelerin oluştuğu gözlemlenmiştir.

Anahtar Kelimeler

• Atık polivinil klorür
• termoplastik köpük malzeme
• kimyasal köpük ajanı
• darbe direnci

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