The Preparation Of Ultraviolet Crosslinking PP/PE Composite Film And Mechanical Properties Research

Polypropylene is widely used in daily life,industrial agriculture and other fields because of its good electrical insulation properties,chemical stability and its high degree of crystallinity.But the crystals in the polypropylene have a large size that results in a poor impact resistance and a decreasing of rigidity in high temperature.And because of the structure defects and the effects of the external environments,polypropylene is apt to degrade in illuminating environments,which limits its applications.Polyethylene is a good modified material for polypropylene,which has a good impact resistance in low temperature,processing fluidity and chemical resistance and so on.In this paper,UV irradiation has been used to help PP,which has a high degree of tacticity,to cross-link,thus improving the strength and anti-aging performance of the PP.Then,a small amount of PE and EPM was added to increase the thoughness of the PP,resulting in a strong and tough material.The results showed that:by the addition of photoinitiator and assistant crosslinker,and after a dose of uv irradiation,we can signficantly improve the mechacical properties of polypropylene material.Based on the analysis of the above data,the crosslinking polypropylene prepared with 0.2 BP,1.6 TMPTA and ultraviolet irradiation quantity to 2000 mj/cm2 showed best performance.It can significantly improve the compatibility between PP and LLDPE by adding a certain amount of ethylene/propylene copolymer as a compatibility agent in the process of PP and LLDPE blend.In composite materials,PP toughness will be improved with the increase of LLDPE content,but too much of LLDPE can lead to material mechanical properties decreased.When the ratio of the composite material is 8:1:1,its mechanical performance is the best.Through molecular sieve load to BP and TMPTA,have obvious influence on the comprehensive performance of composite materials.Molecular sieve in composite materials have the effect of nucleating agent,induce the beta crystal type of polypropylene and make the impact strength of material improvement in the process of crystallization.And due to the effect of slow release of the molecular sieve,the mechanical properties of composite materials has slowimprovement in the course of using it,which can reduce the strength of the material loss.