Mg(OH)_2复合型阻燃剂在PVC中的应用

Application of Magnesium Hydroxide Composite Flame Retardant to PVC Product

研究了氢氧化镁（Ｍｇ（ＯＨ）２）、三氧化二锑（Ｓｂ２Ｏ３）、十溴联苯醚、氧化锌（ＺｎＯ）为主的复合阻燃体系对ＰＶＣ软、硬制品的阻燃作用，开发了复合型阻燃剂。通过正交试验设计、方差分析和回归分析表明，各种阻燃剂之间都存在着交互作用，在本阻燃体系中表现非常突出的为Ｍｇ（ＯＨ）２与Ｓｂ２Ｏ３、ＺｎＯ与十溴联苯醚之间。由于存在着协同作用，添加适当的量即可达到阻燃效果。在热失重分析中，复合型阻燃剂热降解温度区间在３４３．４～４２９．５℃，失重率为１９．２％，而纯Ｍｇ（ＯＨ）２热降解温度区间在３２６．４～４１８．７℃，失重率为２３．９％。该复合阻燃剂用于ＰＶＣ软、硬制品中，除阻燃性能优良（氧指数分别为２８～３８和６５）外，其机械性能均达到国家标准，解决了因添加Ｍｇ（ＯＨ）２而产生的阻燃性能与机械性能相矛盾的问题，其电性能和加工性能良好，且具有一定的抑烟效果。该复合阻燃剂在ＰＶＣ软制品中推荐的用量为１５～２５质量份（以１００质量份ＰＶＣ树脂为基准）；在硬ＰＶＣ制品中推荐的用量为３～５质量份。

s The effects of the composite flame retardant,which was prepared mainly from magnesium hydroxide (Mg(OH) 2),stibium trioxide (Sb 2O 3),decabromodipheny1 oxide(DBDPO) and zinc oxide(ZnO),on the flame retardance of soft/rigid PVC products are studied,resulting in developing a composite flame retardant.The results of orthogonal experiments showed there was synergistic action between the flame retardants,especially between Mg(OH) 2 and Sb 2O 3,ZnO and DBDPO.Because of the synergistic action,only a little amount of flame retardant would bring about flame retardance.The results of TGA showed the thermal degradation temperature of the composite flame retardant was 343.4℃～429.5℃,the weight loss rate was 19.2%,while those of Mg(OH) 2 were 326.4℃～418.7℃ and 23.9 respectively.The composite flame retardants were applied to soft and rigid PVC products,resulting in superior flame retardance (oxygen index 28～38 and 65 respectively),with mechanical properties coming up to national standards.The recommendation content of the composite flame retardant to soft and rigid PVC products were 15～25 PHR (by mass) and 2～5 PHR (by mass) respectively.