Study On Micro-morphology And Properties Of Recycled PET Flakes Modified By ABS

The feasibility of the use of recycled PET flakes(r-PET) modified by ABS to improve the toughness and processability as engineering plastics and the effect of different kinds of extruder, processing technology and content of compatibilizers on mechanical properties, morphology and compatibility of r-PET/ABS blends was studied.The experimental results indicate that reactive extruder is superior to twin-screw extruder and in mixing effect and the mechanical properties; The optimum extrusion temperature is245,260,255,255,240℃, and the optimum screw speed is80r/min. Blending with ABS decrease the MFR and improve the processability of r-PET. The r-PET/ABS(80/20) shows the best mechanical properties in all, it’s tensile strength, non-notched impact strength and notched impact strength enhanced10MPa,6times and near1times respectively compared with pure r-PET. DCS results showed that Tg of r-PET and Tg of SAN before and after blending have no change. Melting temperature and crystallinity of r-PET decreased as the raising of ABS content.ABS-g-MAH and ABS-g-GMA were prepared with reactive extrusion. The effects of DCP contrnt and MAH content on the grafting degree of MAH and the effect of extrusion process on the grafting degree of GMA were studied. The relationship between ratio of graft and mechanical properties heat resistance of ABS were discussed.ABS-g-MAH and ABS-g-GMA were used as the compatibilizer for r-PET/ABS blends. The effects of grafting degree and grafts content on the mechanical properties and morphology of r-PET/ABS blends were studied. ABS-g-MAH and ABS-g-GMA was an effective compatibilizer for r-PET/ABS in which r-PET is the continuous phase, and the impact strength of blends improves greatly. ABS-g-MAH is superior to ABS-g-GMA in compatibilization effect. When grafting rate was1.35%and ABS-g-MAH content was5%, the mechanical properties of r-PET/ABS/ABS-g-MAH blends were optimal, it’s notched impact strength, non-notched impact strength enhanced42%and23%respectively compared with r-PET/ABS.SEM shows that grafted ABS improve the compatibility of the blends, decrease the particle size of the dispersed phases and dispersed more indistinctly. DCS results showed that Tg of r-PET increased and the difference among the Tg of r-PET and ABS is reduced, which indieate that the compatibility between r-PET and ABS was much better with the addition of compatibilizer ABS-g-MAH and ABS-g-GMA.