新型成核剂对聚甲醛树脂结构与性能的影响

Influence of Novel Nucleating Agent on Structure and Properties of Polyoxymethylene Resin

采用新型自制成核剂对聚甲醛(POM)树脂的结晶行为进行调控,以差示扫描量热仪、偏光显微镜、万能材料试验机研究成核剂对POM结构与性能的影响。结果表明,加入成核剂后,POM的结晶速率加快,结晶温度可由143.8℃提高至147.1℃,结晶峰半峰宽可由3.4℃降低至2.3℃,结晶熔融焓和结晶度有所增大;POM球晶细化,直径可由超过200μm降低至不足25μm;POM的拉伸强度由56.6 MPa增大至63.6 MPa,断裂伸长率由46.8%增大至92.3%,缺口冲击强度由6.65 kJ/m2增大至7.83 kJ/m2;随着成核剂用量的增加,POM的结晶行为可进一步得到改善,但力学性能变化不大。

Crystallinity of polyoxymethylene（POM） was tailored by novel nucleating agent, and the structure and properties of POM were investigated by using differential scanning calorimeter, polarizing microscope and mechanical propertis testing machine. The results show that after the induction of nucleating agent, the crystallization rate of POM increases, the crystallization temperature increases from 143.8 ℃ to 147.1 ℃, the half wide of crystallization peak decreases, and the melting enthalpy and degree of crystallinity increase ; the POM spherulite become small, and the diameter of spherulite decreases from 200μm to less than 25 μ m ; the mechanical properties are improved after the induction of nucleating agent ： tensile strength increasing from 56.6 MPa to 63.6 MPa, elongation at break increasing from 46.8% to 92.3%, notched impact strength increasing from 6.65 kJ/m2 to 7.83 kJ/m2. With the increase of nucleating agent conten, the crystallinity of POM can be further improved, while the mechanical properties change little.