生物降解性聚乳酸與多壁奈米碳管複合材料之製備及其性質探討

The Preparation and Properties of Biodegradable PLA/Multi-Walled Carbon Nanotubes Nanocomposites

王彥斌(Yen-Pin Wang)

指導教授 ： 石燕鳳

朝陽科技大學/理工學院/民生化工產業研發碩士專班/碩士(2010年)

摘要

本研究為了增加多壁奈米碳管在聚乳酸奈米複合材料中的分散性，將碳管表面進行化學修飾，首先將多壁奈米碳管浸入HNO3溶液中，進行酸化，使碳管表面帶有羧酸(-COOH)的官能基，可得到酸化後碳管(CNT-COOH)，然後再加入十八烷醇(Stearyl alcohol)，藉由N,N’-二環己基碳二亞胺(N,N’-dicyclohexyl- carbodiimide, DCC)脫水劑脫水，可得到改質後的碳管(CNT-C18)，改質碳管可以分散在acetone、THF、chloroform…等有機溶劑中，再利用熔融混煉方式製備PLA/CNTs奈米複合材料，對於複合材料的熱性質、機械性質及導電性質進行探討。
結果顯示，CNT-C18可以均勻分散在聚乳酸中，有效的改善複合材料的機械性質及導電性質。添加4 wt%的改質碳管CNT-C18複合材料，在40oC下其儲存模數提升了17.8 %，在玻璃轉移溫度(Tg)時損失模數提升了15.1 %。在導電性部分，純聚乳酸材料在添加3 wt%的改質碳管CNT-C18後，其表面電阻由> 10的16次方Ω/cm2降低到 < 10的7次方Ω/cm2，具有抗靜電的效果，未來可用應用在電子產品之外殼上。

關鍵字

聚乳酸 ； 熔融混煉 ； 奈米複合材料 ； 多壁奈米碳管 ； 生物降解性

並列摘要

In order to enhance the compatibility between multi-walled carbon nanotubes (CNTs) and polylactic acid (PLA), the surfaces of CNTs were chemically modified. In this study, CNTs were first pre-treated using acid solution (HNO3) to functional the CNTs surface with carboxylic groups (-COOH), from the acid-treated carbon nanotubes (CNT-COOH). Subsequently, the stearyl alcohol was grafted onto carboxylic groups with the assistance of dehydrating agent, N,N’-dicyclohexyl-carbodiimide (DCC), then we can obtain the modified CNTs (CNT-C18). The CNT-C18 can dispersion in organic solvents, such as acetone, THF, and chloroform. In addition, the PLA/CNTs nanocomposites were then prepared through melt-blending method. The thermal behaviors, morphology, mechanical properties, conductivity of resultant PLA/CNTs nanocomposites were investigated.
The results show that excellent dispersion of nanotubes in the PLA matrices was achieved. Moreover, an improvement in mechanical and conductivity properties was also observed. Nanocomposite with the addition of 4 wt% CNT-C18, the increments of storage modulus (E'') at 40 oC was 17.8 %, and the increments of loss modulus (E'') at glass transition temperature (Tg) was 15.1 %. In the aspect of conductivity, the surface resistivity of the PLA nanocomposites decreased from > 10 16 Ω/cm2 to < 10 7 Ω/cm2 after added 3 wt% CNT-C18. Such PLA/CNT-C18 nanocomposites are highly efficient in anti-static purpose, which can be applied in electronic device outer covering materials.

並列關鍵字

multi-walled carbon nanotubes ； biodegradable ； polylactic acid ； melt-blending method ； nanocomposites

參考文獻

1 S. Komarnei, J. Mater. Chem., 2, 1219, (1982)

3 S. Iijima, Nature, 56, 354, (1991)

8 S. Iijima, Nature, 354, 56, (1991)

9 S. Iijima, T.Ichihashi, Nature, 363, 603, (1993)

10 D. S. Bethune, C. H. Kiang, M. S. Devries, Nature, 363, 605, (1993)