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研究生： 陳宜斈
Yi-Syue Chen
論文名稱： 以二氧化碳發泡技術製備不同成核劑/熱塑性聚氨酯之微米孔洞發泡研究
Preparation of Different Nucleating Agent / Thermoplastic Polyurethane Microcellular Foam by Supercritical CO2 Foaming
指導教授： 葉樹開
Shu-Kai Yeh
口試委員: 胡孝光
Shiaw-Guang Hu
朱建嘉
Chien-Chia Chu
學位類別： 碩士
Master
系所名稱： 工程學院 - 材料科學與工程系
Department of Materials Science and Engineering
論文出版年： 2017
畢業學年度： 105
語文別： 中文
論文頁數： 108
中文關鍵詞： 熱塑性聚氨酯 、成核劑 、多元醇 、二氧化碳 、批次發泡 、膨脹倍率 、泡材密度
外文關鍵詞： Thermoplastic Polyurethane, Nucleating Agent, polyol, carbon dioxide, batch foam, Expansion ratio, foam density
相關次數： 點閱：407  下載：1 
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    • TPU具備可調控硬度、耐磨耗、回彈性佳等特性，而TPU發泡材料，具備低密度、耐磨性、柔韌性和高回彈性，本研究利用CO2做為發泡技術探討添加不同的片狀成核劑對熱塑性聚氨脂(TPU)發泡材料的泡孔結構影響。
    本實驗分成兩大部分，第一部分為自行合成TPU，分別加入不同軟段多元醇(聚四亞甲基醚二醇(PTMEG)、聚丙二醇(PPG)、聚(1,4-丁烯己二酸酯)(PBA))與4,4'-二異氰酸二苯甲烷(MDI)混合反應完全，再加入1,4-丁二醇(BD)及催化劑使其聚合並放入烘箱熟成，形成熱塑性聚氨酯(TPU)。為了比較不同的成核劑在TPU中的成核效率，本實驗加入熱還原氧化石墨烯(TRG)、滑石粉(talc)及奈米黏土(clay)作為成核劑以提升成核效率。
    第二部分利用scCO2以一步批式方法製造TPU發泡材。針對操作條件如含浸溫度來探討與泡孔型態之間的關係，含浸溫度從80-120°C，過去實驗中發現未添加成核劑之TPU發泡材料，泡體中間會有明顯裂縫且泡材外觀不平整，因此添加不同的成核劑來改善此一現象，且同時增加成核點，使形體快速膨脹。我們成功製備出穩定膨脹倍率約4倍的發泡材料。

    Thermoplastic Polyurethane (TPU) possseses many excellent characters such as wear resistance and high resilience. The hardness of TPU can be tuned by changing the ratio or the type of hard and soft segments. In this study, we focus on preparing TPU microcellular foam using different nucleating agents by scCO2 foaming.
    The TPU was synthesized using 4,4’-methylene bis(phenyl isocyanate) (MDI), polyol and 1,4-butanediol(BD) using a pre-polymer method. Poly (tetramethylene ether) glycol (PTMEG), poly (propylene glycol) (PPG), and poly (1,4-butylene adipate) (PBA) were used as polyols. Graphene, talc, or clay was added as the nucleation agent before the chain extension.
    The synthesized TPUs were foamed by one-step batch foaming using scCO2 as the blowing agent. The cell morphology of TPU foam was examined. Adding nucleation agent could improve the cell structure and the appearance of TPU foams.

    摘要 i Abstract iii 誌謝 iv 目錄 v 圖目錄 viii 表目錄 xi 第一章 緒論 1 前言 1 第二章 文獻回顧 4 2.1熱塑性聚氨酯(thermoplastic polyurethane) 4 2.2合成TPU 6 2.2.1二異氰酸酯 7 2.2.2多元醇 8 2.2.3擴鏈劑 9 2.2.4催化劑 9 2.3無機填料 10 2.3.1滑石粉 11 2.3.2熱還原石墨烯 11 2.3.3奈米黏土 11 2.4高分子發泡材料 13 2.4.1發泡劑 13 2.4.2發泡機制 14 第三章 實驗方法 18 3.1實驗藥品 18 3.2實驗儀器 24 3.3實驗流程與步驟 27 3.3.1實驗流程圖 27 3.3.2熱還原石墨烯製備 29 3.3.3熱塑性聚氨酯複合材料之製備 31 3.3.4混煉加工 34 3.3.5批次發泡 34 3.4測量方法 35 3.4.1掃描式電子顯微鏡(SEM) 35 3.4.2穿透式電子顯微鏡(TEM) 35 3.4.3熱重分析儀(TGA) 35 3.4.4示差掃描量熱儀(DSC) 36 3.4.5比表面積測量(BET) 36 3.4.6 X-ray繞射儀(XRD) 37 3.4.7發泡密度量測 38 3.4.8泡孔孔徑(cell size)計算 39 3.4.9泡孔密度(cell density)計算 39 3.4.10膨脹倍率計算 40 第四章 結果與討論 41 4.1成核劑之比表面積測量分析 41 4.2不同比例成核劑/熱塑性聚氨酯複合材料性質分析 42 4.2.1預聚物滴定分析 42 4.2.2不同成核劑/熱塑性聚氨酯之黏度 43 4.2.3熱塑性聚氨酯之硬度量測 45 4.2.4不同成核劑/熱塑性聚氨酯之分子量量測 45 4.2.5不同成核劑/熱塑性聚氨酯之熱分析 49 4.3奈米黏土/熱塑性聚氨酯之XRD分析 54 4.4石墨烯/熱塑性聚氨酯之TEM分析 55 4.5不同比例成核劑/熱塑性聚氨酯發泡材料分析 58 4.5.1添加成核劑對泡孔型態之影響 58 4.5.2添加成核劑對膨脹倍率之影響 68 4.6不同發泡時間對發泡之影響 74 4.6.1藉由不同發泡槽大小來改變發泡時間之泡孔型態影響 74 4.6.2石墨烯/TPU發泡之阻氣效果 82 第五章 結論 84 參考文獻 86 附錄A 量測Tg 取點方法 97 附錄B 藉由公用DSC量測Tm 98 附錄C 緩慢洩壓之實驗 99 附錄D ImageJ軟體換算膨脹倍率 100 附錄E 添加抗縮劑對TPU的效果 103 附錄F 混煉時的最大黏度 104 附錄G 混煉時的平均黏度 105 附錄H DMA實驗 106 附錄I 含浸溫度140°C下PBA+0.1 wt% TRG之發泡實驗 108

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