Preparation Of PVC/Kaolin Nanocomposites Through Solid State Shear Panmilling Method

Polyvinyl-chloride(PVC) is one of the earliest industrialization production plastics in the world, but it is brittle, which defect has greatly restricted the development and the widespread application of the pvc in the further. Therefore, it is necessary to carry on the reinforcing and toughening modification research to obtain better performance pvc material.Firstly, the PVC powder was prepared through solid state panmilling method under the condition of solid phase at the room temperature. After the process of the milling, the multi-level structure and microcrystalline were destroyed; the particle size and molecular weight were decreased. After grinding through 40, the PVC particle size d(0.1) reduced from 84.29μm to 12.46μm; plasticizing time reduced from 294s to 90s; plasticizing and melting rates were increased; torque balance dropped from 42.7Nm to 38.4Nm; processing performance was significantly improved. The elongation of PVC/Kaolin nanocomposites was increased from 57.00% to 202.10% after grinding through 30. The tensile strength increased from 49.50Mpa to 53.25Mpa after 15 milling treatment. The notched impact strength increased from 3.91kJ/m2 to 4.30 kJ/m2 after 10 milling treatment.Pvc/kaolin composite powder (FT-3) and PVC/expantion kaolin composite powder (FT-4) were prepared through solid state shear panmilling method. The structures were characterized by XRD and SEM. The results showed that solid-phase shear milling produces a strong shear, compressionm, friction and other effects , it was cause the physical and chemical changes betweenPVCand Kaolin, kaolin particle size change into samll, the surface area of particles was increased and the interaction between pvc and kaolin was increased. Packed with simple methods, solid phase shear milling Preparation of PVC/Kaolin nanocomposites have greatly improved mechanical properties to achieve the strengthening and toughening.The number of milling, content of kaolin, the rare earth stabilizers and plasticizer content on PVC/Kaolin composite to the mechanical properties were discussed. The results showed that the composite has best mechanical properties when the number of milling is 30, kaolin is 8%, rare earth stabilizer is 3% and the pvc powder is 30%.The results of the SEM and TEM showed that kaolin with a diameter less than 30nm and the aspect ratio of 10 times the nano-particles uniformly dispersed in pvc matrix after the milling. Thermogravimetric analysis showed that the thermal stability of composites is much better than pure PVC material, the pure PVC began to loss weigth at the 122℃, but the composite began to loss weigth at he 156℃, and the weigth of loss is lower than that of pure PVC about 7.12%.