A new kind of inelastomer impact modifier with a coreshell structure was synthesized by employing a multistep composite emulsion polymerization technique, the size and morphology structure of the coreshell particles c...A new kind of inelastomer impact modifier with a coreshell structure was synthesized by employing a multistep composite emulsion polymerization technique, the size and morphology structure of the coreshell particles could be controlled by the multistep composite emulsion polymerization technique. The study of the impact strength and the elongation at break of the PVC/CPE blend with different contents of coreshell particles(CS) indicated that the mechanical properties of PVC/CPE/CS composite were the best when the concentration of the particle was 25%(mass fraction) which showed the different regularities and characteristics of elastomer toughening plastic.展开更多
This research explored replacing acrylic core-shell impact modifier （AIM） by silica fume to toughen PVC. 100%, 75%, 50% and 25% of AIM （8 phr） were substituted by silica fume in PVC respectively, and then processe...This research explored replacing acrylic core-shell impact modifier （AIM） by silica fume to toughen PVC. 100%, 75%, 50% and 25% of AIM （8 phr） were substituted by silica fume in PVC respectively, and then processed by dry blending and twin-screw extrusion. Severe silica fume agglomeration was observed by scanning electron microscope （SEM） in the PVC matrix when 8 phr pure silica fume was used and processed by screw speed of 20 rpm. Its tensile strength was thereby reduced by 38% comparing to unmodified PVC. The silica fume was successfully dispersed while the screw speed was slowed down to 10 rpm to give a stronger screw torque and a longer melt residential time in the extruder. The tensile strength was ’recovered’ to a level comparable to unmodified PVC. Impact test were performed on all formulations extruded at 10 rpm screw speed and synergetic toughening effect was found with 50% substitution and it had the impact strength that was comparable to 8 phr pure AIM toughened PVC.展开更多
文摘A new kind of inelastomer impact modifier with a coreshell structure was synthesized by employing a multistep composite emulsion polymerization technique, the size and morphology structure of the coreshell particles could be controlled by the multistep composite emulsion polymerization technique. The study of the impact strength and the elongation at break of the PVC/CPE blend with different contents of coreshell particles(CS) indicated that the mechanical properties of PVC/CPE/CS composite were the best when the concentration of the particle was 25%(mass fraction) which showed the different regularities and characteristics of elastomer toughening plastic.
文摘This research explored replacing acrylic core-shell impact modifier （AIM） by silica fume to toughen PVC. 100%, 75%, 50% and 25% of AIM （8 phr） were substituted by silica fume in PVC respectively, and then processed by dry blending and twin-screw extrusion. Severe silica fume agglomeration was observed by scanning electron microscope （SEM） in the PVC matrix when 8 phr pure silica fume was used and processed by screw speed of 20 rpm. Its tensile strength was thereby reduced by 38% comparing to unmodified PVC. The silica fume was successfully dispersed while the screw speed was slowed down to 10 rpm to give a stronger screw torque and a longer melt residential time in the extruder. The tensile strength was ’recovered’ to a level comparable to unmodified PVC. Impact test were performed on all formulations extruded at 10 rpm screw speed and synergetic toughening effect was found with 50% substitution and it had the impact strength that was comparable to 8 phr pure AIM toughened PVC.
