低密度聚乙烯共混改性聚苯乙烯的研究

Study on low density polyethylene blending modified polystyrene

主要用同为五大通用合成树脂的低密度聚乙烯(LDPE)对PS进行共混改性,改善PS较脆,耐环境应力开裂,冲击强度低等缺点,提高它的力学性能,以扩大它的应用范围。通过对不同比例的LDPE和PS共混物的拉伸力学测试和冲击性能测试,得到在LDPE质量分数为80%时,共混物的性能最好,拉伸强度达到最大,相对于PS的拉伸强度提高了4.5%,同时断裂伸长率和冲击强度也不低,分别达到了PS的91.7%和84.6%。其性能达到了实际应用的水平,有一定的实用价值,有望进行工业化生产。

The main work of this paper is to modify PS by blending with low density polyethylene（LDPE）,to improve its brittle,environmental stress cracking and low impact strength,so as to improve its mechanical properties,and to expand its application range.By tensile mechanical test and impact test of LDPE and PS blends with different proportions,the best performance and maximum tensile strength of the blends are obtained when the mass fraction of LDPE was 80%.Compared with PS,the tensile strength increased by 4.5%,while the elongation at break and impact strength were also not low,reaching 91.7% and 84.6% of these of PS respectively.Its performance has reached the level of practical application,and has certain practical value.It is expected to carry out industrial production.