Processing and characterization of poly (ethylene terephthalate) based composites


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Kimya Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2004

Öğrenci: MERT KILINÇ

Danışman: GÖKNUR BAYRAM

Özet:

Polymeric composites are any of the combinations or compositions that comprise two or more materials as separate phases, at least one of which is a polymer. By mixing a polymer with another material, such as glass, carbon, or another polymer, it is often possible to improve the desired properties of the polymer. In this study, ternary composites were prepared by using recycled poly(ethylene terephthalate), PET as the matrix material, short glass fiber (SGF) as the reinforcing filler and thermoplastic elastomer as the impact modifier. Bottle grade recycled PET was mixed in a twin screw extruder with a thermoplastic elastomer which is a terpolymer of ethylene/methyl acrylate/glycidyl methacrylate (E-MA-GMA), and E type short glass fiber is fed to the extruder from a side feeder. During this study, recycled PET was mixed with from 10 to 50 wt. % elastomer, and SGF was added to the system in the range from 10 to 40 % by weight. Processing parameters were kept constant during extrusion. The composites were then compression molded for characterization experiments. The produced composites were characterized in terms of their mechanical and thermal properties and morphologies. Melt behavior and fiber length distribution of the composites were also determined for selected composites. In ternary systems with 10 % elastomer, highest tensile strength values were observed. High tensile and flexural moduli values were obtained for the composites containing 20 % elastomer. Results of impact tests designated that impact strength increased significantly after 30 % elastomer content. Thermal analyses of the composites were done by using a DSC (Differential Scanning Calorimeter). Degree of crystallinity of ternary system decreased with increasing elastomer content, but melting points of the composites were not affected significantly. SEM micrographs showed that the adhesion between the