Design And Preparation Of High Performance PVC/carbon Nanocomposites With Segregated Structure

Firstly,the segregated PVC/RGO nanocomposites(s-PVCG)were prepared by direct hot compression of RGO@PVC.Compared with pure PVC and random PVCG(r-PVCG),the electrical conductivity,thermal conductivity,thermal stability and flame retardant properties of s-PVCG are significantly improved.The percolation threshold(?_c)of s-PVCG is as low as 0.012 vol%,and when the RGO content is 2.0wt%,the maximum electrical conductivity of s-PVCG is up to 10^-2S·cm^-1.When the RGO content is 4.1 wt%,the thermal conductivity,maximum thermal weight loss temperature and limiting oxygen index(LOI)of s-PVCG are increased by 75%,21 ^oC and 4^oC,respectively,compared with pure PVC.Secondly,In order to improve the mechanical properties and processing technology of PVC composites,acrylonitrile-butadiene-styrene high rubber powder containing 67 wt%butadiene content(ABS)is chosen as volume exclusion phase and toughening phase for constructing PVC/CCB composites with segregated filler network structure and sea-island phase structure.The volume repulsion of ABS makes the electrical conductivity and thermal conductivity of PVC/ABS/CCB composites increase with the increase of ABS content,and the effective percolation threshold of ABS for the improvement of electrical conductivity and thermal conductivity is 5?8phr and 8?20 phr,respectively.When the CCB content was 5 phr,the conductivity of PVC/ABS/CCB composites with the PVC/ABS ratio of 70/30(10^-11S·cm^-1)was increased by 4 orders of magnitude compared with that of PVC/CCB composites(10^-15S·cm^-1).When the CCB content was 20 phr,the thermal conductivity of PVC/ABS/CCB composites with PVC/ABS a ratio of 70/30(0.121 W·m^-1·K^-1)was52%higher than that of PVC/CCB composites(0.184 W·m^-1·K^-1).When the CCB content was 8 phr,the notch impact strength(24.31 k J·m^-2)of PVC/ABS/CCB composites with PVC/ABS ratio of 70/30 was 107%and 406%higher than that of PVC(11.76 k J·m^-2)and PVC/CCB composites(4.80 k J·m^-2),respectively.In addition,when the content of ABS is less than 20 wt%,the strengthening effect of CCB and the toughening effect of polybutadiene can reach a good match,PVC/ABS/CCB composites can obtain strong and tough mechanical properties.