PE-g-MAHSt接枝共聚物的制备及结晶动力学的研究

材料科学论文编号:CL089  论文字数:9515,页数:30

 目  录
中文摘要 I
英文摘要 II
目录 III
1. 绪论 1
 1.1  引言 1
 1.2  聚乙烯接枝改性方法 1
 1.2.1   自由基接枝机理 1
           1.2.2   离子聚合接枝机理 3
 1.2.3   配位聚合接枝机理 4
 1.2.4  偶联反应接枝机理 4
 1.2.5  其他接枝方法 4
 1.3  接枝单体的选择 5
 1.4  接枝产物的表征 5
 1.5  结晶动力学研究 5
 1.6  论文的研究意义 7
2. 实验部分 8
 2.1  原料与仪器 8
 2.1.1  原料 8
 2.1.2  仪器设备 8
 2.2  实验方法 8
 2.2.1  接枝物的制备 8
 2.2.2  接枝率计算 8
 2.2.3  红外光谱分析 9
 2.2.4  偏光显微镜分析 9
 2.2.5  DSC分析 9
3. 结果与讨论 10
 3.1  接枝物的表征  10
 3.1.1  红外分析 10
 3.1.2  偏光显微镜的分析 11
 3.2  DSC分析 12
 3.2.1  等温结晶动力学 12
 3.2.2  非等温结晶动力学 17
4．总结和展望 23
致谢 24
参考文献 25

摘 要：本论文用自由基聚合方法，制备了苯乙烯、马来酸酐二元接枝低密度聚乙烯共聚物。用红外光谱对LDPE-g-MAH/St进行表征；用偏光显微镜观察接枝后聚合物的晶形，并与低密度聚乙烯的晶形进行比较。利用差示量热扫描热分析仪(Differential Scanning Calorimetry，DSC)研究了改性后的LDPE-g-MAH/St的等温和非等温结晶动力学行为。其中，等温结晶过程分别研究了结晶温度在92、93、94、95℃下的结晶行为，用Avrami方程、Hoffman理论等研究了LDPE和接枝物LDPE-g-MAH/St材料的等温结晶动力学，并且求得Avrami参数n，K（T），t1/2（T）。非等温过程，研究了降温速率分别在5、10、15、30℃/min下的结晶行为，用Ozawa方程，Ozawa和Avrami组合方程研究LDPE和接枝物LDPE-g-MAH/St材料的非等温结晶动力学，结果发现Ozawa方程不适合这个体系，而利用由莫志深提出的Ozawa和Avrami组合方程能很好的描述。
 关键词：低密度聚乙烯；马来酸酐；苯乙烯；接枝共聚物；结晶动力学

Abstract: In this paper, the graft copolymer LDPE-g-MAH/St was prepared with LDPE, monomers of styrene and malefic anhydride via free radical polymerization. The copolymer was characterized by IR. Then the crystal morphology of copolymer was investigated by polarizing microscope. Differential scanning calorimetry (DSC) was used to analyze their isothermal and non-isothermal crystallization behavior. In the isothermal crystallization process, the crystallization temperature was set in 92、93、94 and 95 ° c. The Avrami equation and Hoffman theory was used to analysis LDPE and LDPE-g-MAH/St, then obtained parameters of Avrami equation——n, K (T), t1 / 2 (T).In the case of non-isothermal crystallization, the cooling rate was set in 5, 10, 15, 30 ° c/min respectively. It was found that the Ozawa analysis was rather inapplicable for the copolymer. In contrast, the modified Avrami method, as well as the method proposed by Mo was applied giving satisfactory results.
Keywords：LDPE; MAH; St; Graft copolymer; Crystallization kinetics