PE-g-MAHSt接枝共聚物的制備及結晶動力學的研究

材料科學論文編號:CL089  論文字數:9515,頁數:30

 目  錄
中文摘要 I
英文摘要 II
目錄 III
1. 緒論 1
 1.1  引言 1
 1.2  聚乙烯接枝改性方法 1
 1.2.1   自由基接枝機理 1
           1.2.2   離子聚合接枝機理 3
 1.2.3   配位聚合接枝機理 4
 1.2.4  偶聯反應接枝機理 4
 1.2.5  其他接枝方法 4
 1.3  接枝單體的選擇 5
 1.4  接枝產物的表征 5
 1.5  結晶動力學研究 5
 1.6  論文的研究意義 7
2. 實驗部分 8
 2.1  原料與儀器 8
 2.1.1  原料 8
 2.1.2  儀器設備 8
 2.2  實驗方法 8
 2.2.1  接枝物的制備 8
 2.2.2  接枝率計算 8
 2.2.3  紅外光譜分析 9
 2.2.4  偏光顯微鏡分析 9
 2.2.5  DSC分析 9
3. 結果與討論 10
 3.1  接枝物的表征  10
 3.1.1  紅外分析 10
 3.1.2  偏光顯微鏡的分析 11
 3.2  DSC分析 12
 3.2.1  等溫結晶動力學 12
 3.2.2  非等溫結晶動力學 17
4．總結和展望 23
致謝 24
參考文獻 25

摘 要：本論文用自由基聚合方法，制備了苯乙烯、馬來酸酐二元接枝低密度聚乙烯共聚物。用紅外光譜對LDPE-g-MAH/St進行表征；用偏光顯微鏡觀察接枝后聚合物的晶形，并與低密度聚乙烯的晶形進行比較。利用差示量熱掃描熱分析儀(Differential Scanning Calorimetry，DSC)研究了改性后的LDPE-g-MAH/St的等溫和非等溫結晶動力學行為。其中，等溫結晶過程分別研究了結晶溫度在92、93、94、95℃下的結晶行為，用Avrami方程、Hoffman理論等研究了LDPE和接枝物LDPE-g-MAH/St材料的等溫結晶動力學，并且求得Avrami參數n，K（T），t1/2（T）。非等溫過程，研究了降溫速率分別在5、10、15、30℃/min下的結晶行為，用Ozawa方程，Ozawa和Avrami組合方程研究LDPE和接枝物LDPE-g-MAH/St材料的非等溫結晶動力學，結果發現Ozawa方程不適合這個體系，而利用由莫志深提出的Ozawa和Avrami組合方程能很好的描述。
 關鍵詞：低密度聚乙烯；馬來酸酐；苯乙烯；接枝共聚物；結晶動力學

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