The Influence of Processing Parameters and Use of a Chain Extender on the Mechanical and Thermal Properties of Injection Molded Poly (trimethylene terephthalate) Bioplastic

Poly (trimethylene terephthalate) (PTT), a partly bio-based engineering thermoplastic, was extruded and injection molded and the effect of processing parameters and addition of a chain extender on the engineering properties of the polymer was investigated. The injection molded samples were characterized by thermal, mechanical and microscopic techniques. The heat deflection temperature was found to increase with mold temperature indicating higher and/or more uniform crystallinity of the PTT. In addition, parts molded at higher mold temperatures showed more stable coefficient of thermal expansion below and above the glass transition temperature of the PTT, lending support to the proposed improvement of crystallization by higher mold temperature. The effect of a chain extender additive on the mechanical and thermal properties of the PTT will be presented. The purpose of the study was to optimize the processing conditions for subsequent development of PTT compounds.

Acknowledgement: The financial support from  the Ontario Ministry of Agriculture Food and Rural Affairs (OMAFRA)- University of Guelph Product Development and Enhancement through Value Chains Research Theme; the Ministry of Economic Development and Innovation (MEDI), Ontario Research Fund - Research Excellence Round 4 program and the Natural Sciences and Engineering Research Council (NSERC), Canada for the Discovery grants individual (to Mohanty) to carry out this research is gratefully acknowledged.