紫外光交联无卤阻燃聚乙烯醋酸乙烯酯绝缘材料的研制

Photocrosslinking of Halogen-Free Flame Retardant Ethylene Vinyl Acetate Copolymer/Magnesium Hydroxide Blends

以聚乙烯醋酸乙烯酯(EVA)为树脂基体,氢氧化镁(MH)为无卤阻燃剂,并分别加入表面改性剂硬脂酸(SA)和十一烯酸(UA),通过紫外光辐照进行交联,通过凝胶含量测试、红外光谱、扫描电镜等测试研究了交联及2种不同的表面改性剂对EVA/MH性能的影响。研究结果表明,在含有UA的EVA/MH体系中交联后材料的拉伸强度达到10 MPa以上,断裂伸长率达到150%以上,同时氧指数达到43以上。通过微观研究表明这主要是由于含乙烯基的UA在交联过程中参与了交联反应形成了交联点,同时提高了氢氧化镁与树脂基体EVA的界面作用。

The influence of photocrosslinking and surface modification agent on the properties of halogen-free flame retardant polyolefin blends, which used polyethylene vinyl acetate （EVA） as matrix resin, magnesium hydroxide （MH） as halogen-free flame retardant, and stearic acid （SA） or undecylenic acid （UA） as surface modification agent, was investigated. The obtained results from gel content, FT-IR, LOI, and mechanical property tests show that the tensile strength is higher than 10 MPa, the elongation at break is higher than 150%, and the LOI value reaches 43. The TEM, SEM tests demonstrate that undecylenic acid （UA） can be photo-grafted to the polymer crosslink network and build covalent connection between MH and the EVA matrix during the photocrosslinking process, which result in better mechanical property and flame retardant property.