【作者】 刘婧；

【导师】 张泽朋；

【作者基本信息】 中国地质大学（北京） ， 分析化学， 2007， 硕士

【摘要】 纳米材料因其特殊的性能受到人们的广泛关注,其中聚合物/层状硅酸盐纳米复合材料更是研究的热点。20世纪80年代末Okada等人首次报道了PA6/层状硅酸盐纳米复合材料,其优异的性能引起了国内外研究人员的广泛关注。目前,关于聚合物/层状硅酸盐纳米复合材料的研究主要集中在聚合物/蒙脱石纳米复合材料,并已有部分产品工业化,而聚合物/蛭石纳米复合材料的研究相对较少。本论文以对苯二甲酸二甲酯(DMT)、乙二醇(EG)、蛭石为原料,采用酯交换合成法,通过XRD、TEM、SEM、DSC和氧指数仪等分析表征方法,研究制备聚对苯二甲酸乙二醇酯(PET)/蛭石纳米复合材料,目的是改进PET的性能,提高PET的结晶速率和阻燃性能。论文的主要工作是:提纯蛭石,将蛭石进行有机化处理,通过将对苯二甲酸二甲酯与乙二醇进行酯交换反应制备对苯二甲酸乙二醇酯,再以对苯二甲酸乙二醇酯作为插层剂同有机化蛭石作用进行插层反应,而后加入催化剂使对苯二甲酸乙二醇酯/蛭石插层复合物进行缩合聚合反应,最后制备PET/蛭石纳米复合材料。通过XRD、TEM、SEM、DSC分析表征方法研究了合成制备PET/蛭石纳米复合材料的方法和工艺条件。结果表明,当DMT:EG(摩尔比)=1:1.8,有机蛭石的用量为3%,有机蛭石、EG与催化剂混合均匀后与熔融的DMT在220℃～230℃进行酯交换反应2～3h,而后在230℃～245℃预缩聚反应3h,265℃～278℃缩聚反应3h的工艺条件下,制得了部分剥离型的PET/蛭石纳米复合材料。用DSC、氧指数仪将制得的PET/蛭石纳米复合材料进行分析、测定。结果表明:PET/蛭石纳米复合材料的结晶速率提高,由PET的Tc=200.39℃升至PET/蛭石纳米复合材料的Tc=206.42℃,结晶曲线峰顶温度向高温移动,PET/蛭石纳米复合材料的氧指数由纯PET的21.5%升高至29.4%,阻燃性能得到提高。更多还原

【Abstract】 Nanomaterials have drawn much attention in recent years due to their special properties, and polymer/layered silicate nanocomposites have become the research hotspots. In the late 1980s, Okada et. al. reported PA6/layered silicate nanocomposites, which had so unique properties that caused wide concern for researchers at home and abroad. Now, the research on polymer/layered silicate nanocomposites mainly focuses on polymer/montmorillonite nanocomposites, and some products have realized industrialization. However, there are few reports on the polymer/vermiculite nanocomposites.This thesis used dimethyl terephthalate(DMT), ethylene glycol(EG) and vermiculite as raw material, prepared polyethylene terephthalate (PET) /vermiculite nanocomposites via transesterification method, and characterized the products by XRD, TEM, SEM, DSC and oxygen index instrument. The research purpose is to improve the properties of PET, especially the crystallization rate and flame retardant property.The main content of this thesis is as follows. Vermiculite was purified and organized. Ethylene terephthalate was prepared using DMT and EG by transesterification method. Then ethylene terephthalate, as intercalation reagent, underwent the intercalation reaction with organic vermiculite. After that, catalyst was added to enable the ethylene terephthalate/vermiculite composites process condensation polymerization. Finally, PET/vermiculite nanocomposites were prepared. XRD、TEM、SEM and DSC were utilized to study the synthesis method and reaction condition, indicating that exfoliated PET/vermiculite nanocomposites were prepared under the optimized condition: DMT: EG(mol.)=1: 1.8; organic vermiculite dosage 3%; the homogeneous mixture of organic vermiculite, EG and catalyst reacted with fused DMT for 2～3h at 220℃～230℃, then underwent pre-condensation polymerization for 3h at 230℃～245℃and condensation polymerization for 3h at 265℃～278℃. The results by DSC and oxygen index instrument showed that the crystallization rate of PET/vermiculite nanocomposites was improved from Tc=200.39℃of PET to Tc=206.42℃of PET/vermiculite nanocomposites, the temperature of crystallization peak shifted to higher temperature, and oxygen index of PET/vermiculite nanocomposites increased from 21.5% to 29.4%, indicating theenhancement of flame retardant property.更多还原