Preparation Of Poly Butene-1 Conductive Shielding Materials And Regulation Of Mechanical Properties

Polybutene-1 (PB-1) has excellent heat resistance, stress crack resistance and processability, more than 80 percent of domestic PB-1 products are applied to pipe field and seldom used in other fields. At present domestic PB-1 products show poor performance and low utilization which resulting in serious waste of resources, so it has important practical significance to research the modification and application of PB-1.For the development of PB-1 in conductive areas and broadening the application range of PB-1, carbon black (CB) was used to regulate its conductive properties. In order to improve the mechanical properties of domestic PB-1, CaCO3 was used to regulate its mechanical properties and increase the strength and toughness of the materials. The main area of diatomite is filter aid, for developing the practical value in polyolefin field, PB-1 was selected as matrix to prepare composites which were studied to expand the application of diatomite in different fields.The effect of CB on the conductive and mechanical properties of PB-1/ CB composites were studied and found that the compound CB system which formulated by B-CB and VXC68-CB with 2:6 proportion filled PB-1 at 8 wt%, the volume resistivity of composites decreased to 28.5 Ω·cm, the tensile strength is 26.7 MPa, and elongation at break is 213.0% which reached the indicator of common cable shielding materials.In order to improve the strength and toughness of PB-1, CaCO3 was used to regulate the mechanical properties of PB-1. By comparing the mechanical properties of composites which filled with unmodified and modified CaCO3 found that 2# CaCO3 modified by aluminate coupling agent with 1.5 wt% shown excellent hydrophobicity, meanwhile PB-1 filled at 10 wt% the mechanical properties were best. The notched impact strength of composites was increased by 47.2% than PB-1 filled with unmodified CaCO3 and 56.9% than PB-1 while the composites remained the processing performance of PB-1.In this thesis PB-1/diatomite composites also were prepared for the application of black and white diatomite in polyolefin field. By comparing the mechanical properties and thermal stability found that the flexural modulus of composites reached 1096.8 MPa which was 135.6% higher than PB-1 and showed better enhancement when filled with black diatomite at 30 wt%. The thermal stability of composites prepared by white diatomite was better than black diatomite. The initial thermal decomposition temperature of white products increased by 51℃ than black products when filled with 15 wt% diatomite.