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    Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/5831


    Title: 以有機茂金屬觸媒合成丙烯-原冰烯之COC共聚物及其物性探討;Physical properties of Poly(propylene-co-norbornene) Copolymer using Metallocene Catalyst
    Authors: 鄭孟勳;Meng-Hsun Cheng
    Contributors: 化學研究所
    Keywords: 原冰烯;丙烯;結晶動力學;結晶;結晶型;微結構;norbornene;propylene;crystallization kinetics;crystal;crystal form;mircrostructure
    Date: 2000-06-28
    Issue Date: 2009-09-22 10:08:16 (UTC+8)
    Publisher: 國立中央大學圖書館
    Abstract: 本論文研究是利用rac-bis(Ind)2EtZrCl2/MAO此一有機茂金屬觸媒系統合成丙烯-原冰烯之COC共聚物並探討其物性。我們以不同之合成方式進行共聚反應,可共聚獲得具有結晶性與非結晶之丙烯-原冰烯共聚物。首先,我們發現共聚反應中原冰烯進料濃度增加將會導致共聚物之活性產率下降;而隨共聚反應溫度上升則會增加共聚物之活性產率。共聚物之玻璃轉換溫度除了受共聚物中原冰烯含量多寡的影響之外,還受同排聚丙烯之立體規則性影響。利用核磁共振儀鑑定共聚物之微結構,發現共聚物之微結構主要是以isolated 或是alternating原冰烯單體順序為主。隨著原冰烯含量增加,共聚物之微結構並無太大變化,但高共聚溫度所得之共聚物其微結構中可能有原冰烯diades或是更長的原冰烯單體順序存在。由Hoffman-Weeks方法決定的平衡熔點於163oC。我們發現不管在等溫或是非等溫結晶動力學研究中,單聚物之結晶速率皆高於共聚物之結晶速率,且越多量之原冰烯含量對結晶速率之負面效應越大。單聚物與共聚物皆有regime transition的現象,且其斜率比率皆接近於理論值2。共聚物之折疊表面能(σe)與分子鍊折疊所需要的功(q)約為同排聚丙烯單聚物之4-5倍。另外,同排聚丙烯之結晶型並未因為原冰烯的加入或是較為快速的冷卻速率而有所改變,仍是以α-form的形式存在。 In our studies, the physical properties of poly(propylene-co-norbornene) COC copolymers were investigated which were synthesized using Metallocene catalyst (rac-bis(Ind)2EtZrCl2) and MAO as a co-catalyst. The crystalline and non-crystalline copolymers could be synthesized by different copolymerization procedures. First, the activity of copolymer dramatically decreases with increasing feeding norbornene amount, however, the activity increases with increasing copolymerization temperature. The glass transition temperature of copolymer is affected by two factors: the norbornene content in copolymer and the isotacticity of polypropylene. The microstructure of copolymer is mainly constituent with isolated and alternating norbornene sequence, which is not varied much with increasing norbornene content. Norbornene diades or longer norbornene block sequence probably exists in copolymer which is polymerized under higher reaction temperature. The equilibrium melting point is about 163oC which is determined by Hoffman-Weeks plot. No matter in isothermal or non-isothermal crystallization kinetics, the crystallization rate of isotactic polypropylene homopolymer is higher than copolymer, and the more norbornene content the lower crystallization rate will be obtained. Regime transition occurs in ipp homopolymer and copolymers, and the change in slope approaches about twofold. The fold surface energy(σe) and the work of chain folding(q) of copolymer is about 4-5 folds higher than homopolymer. Finally, the crystal form of polypropylene is stillα-form which is not varied with introducing norbornene unit in polymer chain or faster cooling rate.
    Appears in Collections:[化學研究所] 博碩士論文

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