醇对PE/MMT纳米复合材料形态结构的影响

Effect of alcohol on morphology and structure of PE/MMT nano composite

为了改善由于聚合物形态不佳而影响聚合物堆密度的问题,期望可以通过改变制备条件来控制催化剂的形态,进而得到形态良好的聚合物并提高其堆密度.利用Mg Cl2在醇中溶解和MMT在醇中层间距膨胀的特性,制备了Mg Cl2/Ti Cl4负载MMT层间的催化剂,并通过原位聚合制备了PE/MMT纳米复合材料.通过控制在制备载体时所用醇的种类,利用SEM对催化剂和PE/MMT纳米复合材料的形态结构进行表征.结果表明,醇的碳链长短和用量都会对催化剂和聚乙烯颗粒的形态产生影响.当制备载体所用醇为正丁醇和异辛醇的混合醇且正丁醇、异辛醇和Mg Cl2的摩尔比为2∶0.6∶1时,制得的催化剂和聚乙烯颗粒更接近球形,所得产品中聚乙烯的堆密度可以达到0.34 g/cm3.

In order to solve the problem that the poor morphology of polymer will influence its bulk density,it is expected to control the morphology of catalysts through changing the preparation conditions,and thus to obtain the polymer with good morphology and improve the bulk density of polymer. Through utilizing such characteristics as the dissolution of M g Cl2 in alcohol and the expansion of M M T in the middle layer of alcohol,the catalysts with M g Cl2/ Ti Cl4 being supported between the M M T layers were prepared,and the PE / M M T nano composite was also prepared through in-situ polymerization. Through controlling the types of alcohol used in the preparation of carrier,the morphology and structure of both catalysts and PE / M M T nano composite were characterized with SEM. The results showthat the length of carbon chain and the dosage of alcohol will affect the morphology of catalysts and polyethylene particles. When the alcohol mixed with both butanol and isooctanol is used in the preparation of carrier and the mole ratio of butanol,isooctanol and M g Cl2 is 2∶ 0. 6∶ 1,the prepared catalysts and polyethylene particles are closer to sphericity.M oreover,the bulk density of polyethylene in the obtained product can reach 0. 34 g / cm3.