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 mo...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%.展开更多
The compatibility and phase morphology of poly (phenylcne oxide) (PPO) multi-componenet blends with poly (ethylene terephthalate) (PET) and polystyrene (PS) were studied using differentialscanning calorimetry (DSC), d...The compatibility and phase morphology of poly (phenylcne oxide) (PPO) multi-componenet blends with poly (ethylene terephthalate) (PET) and polystyrene (PS) were studied using differentialscanning calorimetry (DSC), dynamic mechanical analysis (DMA) and scanning electron microsopy (SEM) methods. The effect of glycidyl methacrylate-styrene copolymer (GMS), as a compatibilizer, on the morphology of the PPO blends has also been studied in detail. The influence of the moiecular weight of PET and the synergetic effect of the compatibilizers of GMS and phenoxy on the morphology were examined. The DSC and DMA results show that there are two distinct glass transitions correspondinig to PET and PPO existed, however, the Tg of PPO shifts toward lower temperature region due to the addition of GMS and PS. The SEM results reveal that PET component is as dispersed phases in the PPO matrix, part of which is located at the interfaces due to the interaction with GMS while PS is miscible in the PPO matrix. A展开更多
文摘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%.
文摘The compatibility and phase morphology of poly (phenylcne oxide) (PPO) multi-componenet blends with poly (ethylene terephthalate) (PET) and polystyrene (PS) were studied using differentialscanning calorimetry (DSC), dynamic mechanical analysis (DMA) and scanning electron microsopy (SEM) methods. The effect of glycidyl methacrylate-styrene copolymer (GMS), as a compatibilizer, on the morphology of the PPO blends has also been studied in detail. The influence of the moiecular weight of PET and the synergetic effect of the compatibilizers of GMS and phenoxy on the morphology were examined. The DSC and DMA results show that there are two distinct glass transitions correspondinig to PET and PPO existed, however, the Tg of PPO shifts toward lower temperature region due to the addition of GMS and PS. The SEM results reveal that PET component is as dispersed phases in the PPO matrix, part of which is located at the interfaces due to the interaction with GMS while PS is miscible in the PPO matrix. A
