Influence of Molding Condition on the Properties of Dressed and Functionalized Nanocomposites Based on Low Density Polyethylene

摘要

The results of a study of the effect of injection molding on the physicomechanical and technological properties of nanocomposites based on low density polyethylene functionalized with maleic anhydride and talc dressed with gg-aminopropyltriethoxysilane are presented. As the object of study, nanocomposites with 5.0 and 30 wt % of dressed talc were used. Properties such as breaking stress, elongation at break, flexural strength, and volumetric shrinkage were investigated. It was found that the introduction of dressed talc in the composition of chemically modified low density polyethylene contributed to some increase in the breaking stress and the flexural modulus of the nanocomposite. Experimental studies were carried out in a wide range of temperatures of the material cylinder and casting pressure. It was found that relatively high physical and mechanical properties were achieved in samples obtained at higher temperatures in the zones of the material cylinder. The casting pressure ranged from 50 to 150 MPa. It was found that relatively high physicomechanical and technological properties for nanocomposites with 5.0 and 30 wt % talc content were achieved at a temperature of the material cylinder in the zones of 110–130–160–180°C and a casting pressure of 150 MPa. A significant reduction in volumetric shrinkage is achieved in samples with 30 wt % talc content. The influence of mold temperature and holding time under pressure on the change in the properties of nanocomposites is considered. It is shown that the optimal mode in the cooling mold for samples with 5.0 wt % talc content is 50°C and the exposure time under pressure of 20 s, and for a nanocomposite with 30 wt % talc content, 50°C and holding time 10 s. The influence of the location of the gate device relative to the surface of the sample on the change in the properties of composite materials is studied. The scientific substantiation of the discovered patterns in changing the properties of nanocomposites is given.