微波法合成黄原胶与丙烯酰胺接枝共聚物及其表征

Synthesis and characterization of the graft copolymer of xanthan gum and acrylamide by microwave irradiation

对微波法聚合反应制备黄原胶(XG)-丙烯酰(AM)共聚物的工艺条件进行研究。主要考察黄原胶质量浓度、单体配比、引发剂质量浓度、反应时间及微波火力等因素对产品接枝率和接枝效率的影响,探讨黄原胶接枝丙烯酰胺共聚反应的基本规律以及接枝机理;采用红外光谱仪(FT-IR)、元素分析仪(EA)和X射线粉末衍射仪(XRD)对接枝共聚物的结构进行表征。结果表明,最佳反应条件为:XG质量浓度为12g/L,m(AM)∶m(XG)=4∶1,过硫酸铵(APS)质量浓度为2g/L,反应时间为5min,采用微波低火(160W)加热。在最佳反应条件下,产品的接枝率和接枝效率分别为135%和82.1%。

The graft copolymers of xanthan gum and acrylamide was synthesized by microwave irradiation. The effects of various factors on grafting ratio and grafting efficiency were studied including xanthan gum mass concentration, monomer ratio, initiator mass concentration, reaction time and microwave power. The reaction regularity of grafting polymerization in initiation system was discussed. The mechanism of graft copolymerization was proposed to explain the formation of radicals and the initiation. The graft copolymers were characterized and analyzed by FT-IR,EA and XRD. The results showed the optimal synthetic conditions of xanthan gum mass concentration being 12 g/L, m（AM）：m（XG）=4：1, initiator mass concentration being 2 g/L and reaction time being 5 min at lower power （160 W）. The graft ratio and graft efficiency are 135% and 82.1% respectly through the optimal synthetic conditions.