聚胺酯/有機黏土奈米複合材料之合成製備及鑑定

Synthesis, Preparation and Characterization of Polyurethane/Organoclay Nanocomposites

張美玲(Mei-Ling Chang)

指導教授 ： 王賢達

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2005年)

摘要

本研究主要是利用合成和混煉加工二種方法，來製備聚胺酯/有機黏土奈米複合材料，藉以提高聚胺酯的機械性質及熱穩定性。
研究的第一部份為合成法：有機蒙脫土(Cloisite30B)改質劑中的-OH極性末端基，可與聚胺酯前導物反應，使得蒙脫土以奈米尺寸均勻且剝層分散在聚胺酯高分子基質中。經由GPC平均分子量的分析，聚胺酯/有機黏土的平均分子量隨著反應時間增加而增高，並由1H-NMR及FTIR鑑別，Cloisite30B改質劑和聚胺酯分子之間的鍵結。第二部份為混煉加工法：將醚型聚胺酯材料經由雙輥筒混煉機(brabender)和Cloisite30B進行混煉加工，使蒙脫土均勻的揷層分散在聚胺酯分子鏈中，但黏土與高分子之間並無合成法得到的複合材料之鍵結。
藉由FTIR光譜分析，比較R値(硬節鏈段氫鍵鍵結指數)，可知聚胺酯/有機黏土材料其硬節區在有少量黏土時，可以增加氫鍵鍵結，黏土量大時，反而降低氫鍵鍵結。經由XRD及TEM的鑑定，合成法製備的聚胺酯/有機黏土為接近剝層的結構；混煉加工法製備的聚胺酯/有機黏土為插層結構。機械性質結果顯示：合成法製備的聚胺酯/有機黏土材料，當有機黏土含量0.84wt%時，熱裂解溫度提高23℃，模數提高370%，抗拉強度提高400%，斷裂延伸提高70%。混煉加工法製備的聚胺酯/有機黏土材料，有機黏土含量0.025~0.1 wt%時，熱裂解溫度提高4~5℃，軟節Tg提高2~8℃，硬節Tg提高5℃。

關鍵字

聚胺酯 ； 有機黏土 ； 奈米複合材料

並列摘要

Polyurethane/organoclay nanocomposites were prepared using synthetic and melt-blended methods﹒
Terminal –OH groups of Cloisite30B reacted to OCN– groups of polyurethane prepolymer in synthetic method, and this has been verified from increases in average molecular weights of polyurethanes upon increasing reaction time﹒1H-NMR and FTIR spectra also confirmed the existence of chemical linkage between polyurethane and modifier of Cloisite30B﹒For polyurethane/organoclay nanocomposites were prepared via melt-blended method, however, it would not show any increase in average molecular weights of polyurethane﹒Instead, chain lengths were cut short due to polymer degradation during melt-blended process﹒In addition, 1H-NMR spectrum would not support any evidence of chemical bonding between polyurethane and clay﹒
XRD data did not show any crystalline information of clay for nanocomposites prepared from both methods﹒Nevertheless, TEM photographs indicated exfolinted dispersion of clays for nanocomposites prepared from synthetic method and intercalated dispersion of clays for nanocomposites prepared from melt-blended method﹒
Hydrogen bonding index(R) obtained from FTIR spectra gave strength of hydrogen bonding information for hard domain﹒Apparently, R value would increase first and decrease upon increasing the amount of organoclay, and the effect of clay content for nanocomposite obtained from melt blends to R value would be larger compared to that of sample prepared from another method﹒
Nanocomposite prepared with synthetic method showed 23℃ higher in thermal degradation temperature, 370% higher in modules, 400% higher in tensile strengher and , 70% longer in tensile elongation, relative to polyurethane, for sample with 0.84% organoclay content﹒Interestingly, nanocomposites obtained from melt-blended method with organoclay content between 0.025~0.1wt% gave higher thermal degradation temperature(4~5℃), higher Tg for soft domain(2~8℃), higher Tg for hard domain(5℃) compared to polyurethane﹒

並列關鍵字

Polyurethane ； Organoclay ； Nanocomposites

參考文獻

[19]、葉日豪, “聚氨基甲酸酯/黏土奈米複合材料之製備與性質研究”, 碩士論文,私立中原大學化學研究所, 桃園, 2002。

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