Author(s)

Wiranphat Thodsaratpreeyakul^1*, Putinun Uawongsuwan², Takanori Negoro³

¹Department of Biobased Materials Science, Kyoto Institute of Technology, Kyoto, Japan.
²Department of Materials and Production Technology Engineering, King Mongkut’s University of Technology, North Bangkok, Thailand.
³NEGORO SANGYO Co., Ltd., Osaka, Japan.

In this research, recycled-polyethylene terephthalate (PET) and polycarbonate (RPET/PC) blends fabricated by vented barrel injection molding were presented to better understand the effect of devolatilization during molding process. The effect of dried pellets, non-dried pellets, using an opened-vented hole, and using a closed-vented hole on the miscibility, morphology, thermal properties and mechanical properties of RPET/PC blends was investigated. The results indicated that no drying decreases dispersion, thermal properties, and mechanical properties of RPET/PC blends due to hydrolysis degradation of recycled-PET during the injection molding process. Using the venting system with non-dried RPET/PC blends partially improves dispersion, thermal properties and molecular weight of RPET/PC blends processed without drying, giving results that are similar to those processed with drying. Regarding the flexural properties, using the venting system without drying prevents the flexural properties from decreasing in RPET/PC blends, if the amount of RPET is less than 75 wt%. When the content of RPET is over 75 wt%, using the venting system does not eliminate the decrease in flexural properties of RPET/PC blends. When the venting system is applied to non-dried RPET, despite hydrolysis degradation of RPET not being completely eliminated, the damaging effects are nonetheless reduced compared with those samples processed without the venting system. As a result, vented barrel injection molding hardly prevents non-dried RPET/PC blends from having reduced flexural properties when the content of RPET is greater than 75 wt%.

Polymer Blends, Recycled Poly(Ethylene Terephthalate), Polycarbonate, Vented Barrel Injection Molding

Thodsaratpreeyakul, W. , Uawongsuwan, P. and Negoro, T. (2018) Properties of Recycled-Polyethylene Terephthalate/Polycarbonate Blend Fabricated by Vented Barrel Injection Molding. Materials Sciences and Applications, 9, 174-190. doi: 10.4236/msa.2018.91012.