磷钨酸根插层LDHs的制备及其对环氧树脂的阻燃性能研究

Preparation of phosphotungstic acid intercalated layered double hydroxides and their flame retardancy on epoxy

采用共沉淀法将磷钨酸根(PWA)柱撑插层层状双金属氢氧化物(LDHs)制备了MgAl-LDHs-PWA,通过X射线衍射(XRD)、红外光谱(FT-IR)、扫描电镜(SEM)等手段对其结构和形貌进行了表征,并对其热稳定性进行分析。结果表明:PWA插入LDHs层间,且MgAl-LDHs-PWA的热稳定性与残余量得到大幅度提升。同时,对环氧树脂(EP)/MgAl-LDHs-PWA复合材料的阻燃性能及力学性能进行了评价。结果表明:当添加质量为20%时,EP/MgAl-LDHs-PWA复合材料的极限氧指数(LOI)为26.2%,垂直燃烧(UL-94)达到V-0等级。EP/MgAl-LDHs-PWA复合材料的拉伸强度和断裂伸长率分别为29.28MPa和3.6%。

Phosphotungstic acid intercalated layered double hydroxides(MgAl-LDHs-PWA)were prepared by co-precipitation method.The structure and morphology of the MgAl-LDHs-PWA materials were characterized by XRD,FT-IR and SEM,and the thermal stability was also analyzed.The results indicated that the MgAl-LDHs were successfully intercalated by PWA anion.TGA confirmed that both the thermal stability and the residue formation of the MgAl-LDHs-PWA materials were significantly enhanced.The flame retardancy and mechanical properties of EP/MgAl-LDHs-PWA composites were evaluated.The results showed that the composites could achieve the LOI value of 26.2%and the UL-94 of V-0 level when the added mass was 20wt%.The mechanical testing revealed that the tensile strength and the elongation at break of EP/MgAl-LDHs-PWA were 29.28MPa and 3.6%,respectively.