反应介质对制备AC/MMT复合发泡剂的影响

分别以水/二甲基亚砜(H2O/DMSO)、超临界二氧化碳为介质,将偶氮二甲酰胺(AC发泡剂)插层到蒙脱土(MMT)层间,制备得到AC/MMT复合发泡剂。通过红外光谱、热失重、X射线粉末衍射、扫描电子显微镜等方法对产品进行表征,考察反应介质对AC/MMT复合发泡剂中AC发泡剂插层量、AC发泡剂分解温度以及MMT形貌的影响。研究表明,两种介质均能成功制备得到AC/MMT复合发泡剂,以超临界二氧化碳为介质时钠基蒙脱土(Na-MMT)中AC发泡剂插层量最大,为14.34%;Na-MMT中AC发泡剂的分解温度主要受反应介质的影响且以H2O/DMSO为介质时AC发泡剂的集中分解温度由226℃降低至173.21℃;两种反应介质均能够改善MMT的团聚结构,以超临界二氧化碳为介质时更能够使得MMT结构变得蓬松、无序。应用于聚丙烯发泡材料中效果良好。

Effects of Reaction Medium on AC/Montmorillonite Composite Foaming Agent

Intercalating azodicarbonamide (AC foaming agent) to montmorillonite (MMT) layers using different reaction me-diums (water/dimethyl sulfoxide,supercritical carbon dioxide) can improve MMT reunion phenomenon and reduce decomposition temperature. The effects of the reaction mediums on the amount and decomposition temperature of intercalated AC foaming agent and MMT morphology were investigated by FTIR,SEM and TG. As experimental results show,AC/MMT composite foaming agent were successfully prepared in both two mediums. Supercritical carbon dioxide as the reaction medium can increase the amount of AC foaming agent intercalation of Na-montmorillonite (Na-MMT) to 14.34%. Water/dimethyl sulfoxide as the medium is more conducive to reduce AC foaming agent decomposition temperature in Na-MMT,AC foaming agent decomposition temperature de-creases from 226℃ to 173.21℃. Both reactions media are able to improve the structure of MMT agglomeration structure and super-critical carbon dioxide as medium can make MMT's structure become morefluffy and disordered. AC/MMT composite foaming agent is used to obtain the good effect in polypropylene foaming material.