Highly Liquid Polyethylene Specialized Material And Its Modification

In this paper, the structure and properties of Y#, a new high-fluidity polyethylene material produced by Yangzi Petrochemical Company Ltd., was systematically characterized. Y# was compared with similar samples of 7200(Formosa Plastics) and 52518(Iran Petrochemical). Thanks to the poor properties of Y#, modified Y# samples were obtained by blending the metallocene polyethylene with it. Then the improving effect of mPE's content on the structure and properties of Y# was studied. The results confirmed that Y# had a high mobility, the MFR of which was 19g/10min. The tensile strength, elastic modulus, tensile stress at break and bending strength of Y# were high, but its impact strength was not appropriate.The addition of mPE increased the apparent viscosity of Y# at 180℃, which made its mobility become worse. But when the temperature rose to above 200℃, mPE's accession had little effect on the mobility and apparent viscosity of Y#; The introduction of mPE made little change on the crystallization temperature, but the melting peak temperature and crystallinity increased. When the addition content of mPE reached 20wt%, the blends owned the maximum crystallinity; mPE's accession significantly increased the impact strength at room temperature and low temperature of Y#, while the tensile strength, elastic modulus, tensile stress at break, bending strength and bending modulus slightly decreased, which basically maintained the rigid of Y#; When the content of mPE reached 20wt%, the modified sample had the best comprehensive properties. Its tensile strength was 21.78MPa, tensile stress at break was 11.53MPa, bending modulus was 1019.21MPa, bending strength was 23.47MPa, the break elongation was 136.62%, IZOD impact strength at room temperature and low temperature was respectively 3.983 and 3.654KJ.m-2, the melt flow rate was 19.4g/10min, melting peak temperature was 135.6℃, the crystallization temperature was 121.67℃and crystallinity was 60.5%.