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題 名 | 聚酯二元醇結構對不黃變PU成品物性及加工性之影響 |
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作 者 | 李大剛; 杜佾璋; 賴聖淵; | 書刊名 | 宜蘭農工學報 |
卷 期 | 8 1994.06[民83.06] |
頁 次 | 頁47-65 |
分類號 | 467.4 |
關鍵詞 | 聚酯二元醇; 結晶; 極性; 不黃變; 彈性體; 合成皮樹脂; 加工性; Polyester polyol; Crystalline; Polarity; Non-yellowing; Elastomer; Synthesis leather; Processing ability; |
語 文 | 中文(Chinese) |
中文摘要 | 以六種不同之二元醇( ethylene glycol, EG; diethylene glycol, DEG; 1,4- butylene glycol, 1,2-prophylene glycol, PG; neopentylene glycol, NPG; 及 hexylene glycol, HG )與二元酸( adipic acid, AA )於適量催化劑( tetrabutyl titanate )下,進行酯化聚合反應,合成一系列化學結構不同,分子量 2,000g/mole 之聚 酯二元醇( polyester polyol )。 一系列 PU 彈性體利用上述六種聚酯二元醇為軟段, 異佛爾酮二異氰酸鹽( isophorone diisocyanate, IPDI )與 1,4- 丁一醇( 1,4-BG )為硬段。 用 one shot 方法製造硬段 含量= 40% 之不黃變 PU 彈性體, 其代號相對之為 1-4, 2-4, 3-4, 4-4, 5-4 及 6-4 供 拉力試驗、微分掃瞄熱卡計( DSC )、動態-機械分析儀( DMA )、撕裂強度及硬度測試 。 利用 prepolymer 方式合成固含量 30% 之樹脂做耐水解及厚度保持率等測試。用以探討 聚酯二元醇中, 二元醇化學結構之( 1 )對稱性( 2 )極性( 3 )重覆單體上碳之數目 ,對於 PU 成品的物性及用做合成皮原料時之相關加工特性之影響。用以開發不黃變 PU 特 性樹脂、彈性體配方及加工程序設計。 IPDI 為具二不對稱之脂肪族異氰酸鹽基結構, 不易生成結晶結構,故其成品之高溫穩定性 不佳,90 ℃以上之反應溫度會造成裂解使成品帶色。 以具對稱結構之聚酯二元醇為軟段製 成之 40% 硬段含量之成品( 1-4, 2-4, 3-4 及 6-4 )因有較強之分子內作用力及極性故 有軟段結晶生成,其成品均為不透明,而以不對稱結構之聚酯二元醇製成之相對成品( 4-4 及 5-4 )則因立體障礙性而無結晶之生成,故成品呈清澈透明。 一般以聚酯二元醇為原料 之成品較相對之聚醚二元醇成品有較強之分子內氫鍵,故其機械強度較高。此系列 PU 成品 有良好之機械強度及延伸率(均> 400% )。 其中對稱結構者( 1-4, 3-4, 6-4 )又較不 對稱結構( 4-4, 5-4 )者為佳,且對稱結構者在高延伸率(> 300% )會有定向延伸結晶 之生成使其拉力急速上升。 此系列以 IPDI 為原料之成品在 75 ℃左右其儲存模數均降至 5x10 �� N/m �揖H下, 呈 rubbery 狀態,不適於濕式合成皮樹脂使用。其中對稱性結構之聚酯二元醇之成品有較佳之 耐熱性,而結構中同時夾雜著醚基結構之 2-4 其耐熱性最差。 以結構對稱聚酯二元醇為料 之 PU 成品有較佳之撕裂強度及較高之硬度,主要是由於其成品有較高之韌度。耐水解性則 以具不規則性結構, 極性較低之 4-4, 5-4 及含醚基結構之 2-4 較優,而對稱結構者以酯 基密度及相對極性較低之 6-4 為佳。 |
英文摘要 | A series of polyester polyols with Mn = 2,000 g/mole formed by polyesterfication method. There are six different diols: ethylene glycol (EG), 1,2-propylene glycol (PG), 1,4-butylene glycol (BG), diethylene glycol (DEG), neo-pentylene glycol (NPG), and hexylene glycol (HG); respectively, reacted with adipic acid in the presence of tetrabutyl titanate as the catalyst. All the non-yellowing polyurethane specimens are produced by using these polyester polyols as the soft segment and the hard segment is formed by isophorone diisocyanate (IPDI) reacted with BG. The hard segment content was fixed at 40%. The codes are 1-4, 2-4, 3-4, 4-4, 5-4, and 6-4; respectively. One-shot non-yellowing PU elastomer specimens are prepared for tensile stress-strain measurement, tear strength measurement, differential scanning calormetry (DSC), dynamic-mechanical analysis (DMA), to study the effects of polyester polyol chemical strcutures on the mechanical, fracture, thermal and dynamic mechanical properties. Wet process synthesis non-yellowing polyurethane leather are made by prepolymer solution casting method to investigate hydrolysis resistance and thickness maintenance ratio of the PU products. PU products based on the polyols with symmetry structure (1-4, 2-4, 3-4 and 6-4) are opaque due to the polyols have strong intermolecular force and polarity caused the soft segment crystalline. On the other hand the material based on the polyols with pendant group (4-4, 5-4) are transparent ascribed to the structure irregularity. All polyester polyol based PU products have better mechanical properties than the corresponding polyether polyol based materials due to the strong intermolecular force (hydrogen bonding). In this study, all PU products posses good tensile strengh and elongation (>400%), PU based on symmetric polyols (1-4, 3-4, 6-4) have better mechanical porperties than those based on unsymmetric polyols (4-4, 5-4) and the former materials displays stretch oriented crystallization at elongation higher than 300%. IPDI is an aliphatic diisocyanate with unsymmetric isocyanate stucture, it is difficult to form crystalline. Therefore, materials based on IPDI degraded at 90 ℃ and colored. In this study, polyester polyol/BG/IPDI based PU materials' at 75 ℃ are rubbery state and its storage modulus fell below 5x16 �� N/m ��. PU based on the symmetric polyols with better structure regularity and stronger intermolecular force show better high temperature stability, tear strength and hardness than those based on unsymmetric polyols. PU based on unsymmetric polyols with weaker intermolecular force and polarity display better hydrolysis resistance than those based on symmetric polyols. |
本系統中英文摘要資訊取自各篇刊載內容。