聚丙烯高支化聚乙烯合金的制備與性能

化工論文編號(hào):HG218  論文字?jǐn)?shù):19170,頁數(shù):36

目  錄
中文摘要   I
英文摘要  Ⅲ
目錄  Ⅴ
1 緒論 1
1.1前言 1
1.2 丙烯聚合的催化劑 2
1.2.1前過渡金屬催化劑 3
1.2.2 茂金屬催化劑 3
1.2.3 后過渡金屬催化劑 4
1.3 丙烯聚合工藝 5
1.3.1 聚丙烯氣相法 7
1.3.2 聚丙烯淤漿法 7
1.3.3 聚丙烯本體法 8
1.3.4 聚丙烯本體法-氣相組合法 9
1.4 聚丙烯低溫抗沖性能的改進(jìn) 10
1.4.1 物理共混 11
1.4.2 原位合金 12
1.5  研究目的與方法 12
2  實(shí)驗(yàn)部分 13
2.1 原料及預(yù)處理 13
2.1.1 原料 13
2.1.2 原料的預(yù)處理 14
2.2. 載體制備 15
2.2.1 制備方法 15
2.2.2 制備工藝 15
2.3 聚丙烯球負(fù)載催化劑制備 16
2.3.1 催化劑前體制備 16
2.3.2 負(fù)載催化劑制備 17
2.4負(fù)載催化劑表征 17
2.5 聚合物表征 18
3 聚合反應(yīng) 18
4 實(shí)驗(yàn)結(jié)果與討論 19
4.1 乙烯聚合 19
4.2 聚合物性質(zhì) 21
4.2.1 聚乙烯的DSC 21
4.2.2 聚乙烯的結(jié)構(gòu) 23
4.2.3 聚乙烯的分子量和分子量分布 25
4.2.4 聚合反應(yīng)動(dòng)力學(xué) 27
4.2.5 合金形態(tài) 27
5 結(jié)論 29
致  謝 30
參考文獻(xiàn) 30

摘要：聚丙烯是一種極有價(jià)值的化工材料，有很多良好性能，但還缺乏固有的韌性，特別是在低于其玻璃化溫度的條件下,所以可以通過添加沖擊改性劑，提高其抗沖擊性能。本實(shí)驗(yàn)通過在聚丙烯極性球體內(nèi)負(fù)載后過渡金屬催化劑，使其只需要通入單一原料乙烯，形成高支化聚乙烯，在合適的操作條件下形成高支化聚乙烯/聚丙烯合金。本文采用在聚丙烯極性球體內(nèi)負(fù)載后過渡金屬催化劑制備合金的方法，首先將后過渡金屬催化劑二－（2,6-二甲基苯基）戊二亞胺溴化鎳負(fù)載到聚丙烯極性球體內(nèi)，再使乙烯在PP球中聚合，改變反應(yīng)溫度得到含不同支化度的聚乙烯與聚丙烯的反應(yīng)器內(nèi)合金，測定了不同樣品的基本性能，
研究發(fā)現(xiàn)，引入少量極性官能團(tuán)的聚丙烯可以作為后過渡金屬催化劑的良好載體。通過調(diào)節(jié)操作參數(shù)，如溫度，可以制備得到不同支化度聚乙烯與聚丙烯的合金。當(dāng)反應(yīng)溫度從20℃升高到50℃，聚乙烯的支化度從20.0增加到130.4。聚乙烯的主要支鏈?zhǔn)羌谆�，隨著反應(yīng)溫度升高，盡管支鏈主要由甲基組成，但戊基以及長支鏈含量迅速增大。
關(guān)鍵詞：聚丙烯；高支化聚乙烯； 二亞胺鎳催化劑；二氫月桂烯三甲基硅醚

Abstract：Polypropylene is a valuable chemical material with a lot of good performance, but it has an inherent lack of tenacity, especially below its glass transition temperature. Its impact-resistance can be modified by adding elastomers.
In this paper, brPE/iPP alloy was obtained under appropriate operating conditions by ethylene polymerization in iPP particles, which was catalyzed by late transition metal catalyst supported in the functionalized iPP particles. First, functionalized polypropylene was prepared with Z-N catalyst in a 2-liters reactor at 70℃ and 2atm. Then the late transition metal catalyst bi-(2,6-dimethylphenyl) pentane diimine nickel dibromide was supported on the fuctionalized iPP particles. When ethylene was input in the reactor, ethylene diffused into iPP particles and polyethylene formed in iPP particles. The obtained product is an alloy of polypropylene and branched polyethylene. By varying the polymerization temperature, the branching degree of polyethylene can be tuned and different brPE/iPP in-reactor alloy could be obtained. Besides the process, we investigated the basic properties of these products.
Experiments showed that the functionalized polypropylene is a good support material for late transition metal catalyst. By adjusting the operating parameters such as temperature, brPE/iPP in-reactor alloy can be prepared When the polymerization temperature increased from 20 ℃ to 50 ℃, the branch of polyethylene varied from 20.0 to 130.4. The branch chain mainly consist of methyl branch, but with the temperature increasing, the long branches, especially amyl , hexyl and longer than hexyl, increase rapidly and the content of long branches are comparable to that of methyl branch.
Keywords: Polypropylene; high-Polyethylene; diimine nickel catalyst; dihydro Myrcene three-silicon ether