乾式法製備LDPE/PE-g-MA/STAC/Clay奈米複合材料和[LDPE][LDPE/PE-g-MA/STAC/Clay]雙層膜及其性質的研究

低密度聚乙烯薄膜(LDPE)現今主要應用在包裝材料領域中，但是由於它有拉伸強度不佳、阻氣性和阻水性不佳等缺點，因此使用複合材料來代替LDPE。惟全部使用複合材料來製備薄膜，則成本太過昂貴。本研究的主要目的在改善LDPE之上述缺點。先利用STAC在80℃下改質膨潤土，再利用單螺桿押出機製備出不同黏土含量的LDPE/PE-g-MA/Clay奈米複合材料；為了節省成本，使用吹膜機利用共擠押吹膜製程，以少量複合材料，製備出[LDPE]/[LDPE/PE-g-MA/Clay]雙層奈米PE膜。研究結果得到以下結論：1.奈米複合材料：(1)利用TGA測量熱性質，發現黏土可提高複合材料的裂解溫度(Td)和灰合殘留量。(2)玻璃轉換溫度(Tg)與原來的LDPE相距不大，證明加入Clay並不會造成材料遇高溫時會過度軟化。(3)藉由UV-Vis鑑定其透光度，黏土可改善奈米複合材料的可見光透光度以及紫外線阻抗性。2.奈米LDPE膜(1)對穿透度測量而言，高含量黏土的奈米LDPE膜具有高的可見光透光度以及紫外線阻抗性。(2)硬度測量方面，奈米LDPE膜由於經過吹膜會增加其硬性，因此都具有3B的程度。(3)在機械性質測試方面，我們得知添加奈米複合材料之LDPE膜有較佳之阻水性、阻氣性、拉伸強度及破裂強度。經本研究可以得知LDPE/PE-g-MA/6%Clay奈米複合材料具有較佳機械性質，經過吹膜後的6% Nano LDPE Film，其性質也相對提高，此外黏土分散也較均勻，可以改善純LDPE所具備機械強度不高、質軟、成型收縮率大、表面硬度不佳等缺點，使此新改良材料具有較高的應用性。

關鍵字

奈米複合材料； LDPE ；黏土；單螺桿押出機；共擠押吹膜

並列摘要

Low-density polyethylene (LDPE) film is currently used in packaging materials. However, it has poor tensile strength, gas barrier and water-blocking and other shortcomings. Therefore, composite materials are used instead of LDPE. But all use of composite materials is too expensive to prepare the film.This study was to improve the above shortcomings. Firstly, STAC was added to modify bentonite at 80℃. Then, using the single-screw extrusion, the different clay content of LDPE/PE-g-MA/Clay nano composites could be produced. Finally, for saving cost, using a small amount of composites produced [LDPE]/[LDPE/PE-g-MA/Clay] double nano PE film by co-extrusion blown film machine.The following conclusions for the results of the study:1. For the nano-composites:(1) Form the TGA measurement of thermal properties, the clay can increase the decomposition temperature of composites (Td) and ash residues.(2) From Glass transition temperature (Tg) is not the original LDPE apart, proved to join Clay material when the temperature does not cause excessive softening.(3) Form the UV-Vis transmittance, clay could improve the visible light transmittance and ultraviolet resistance of the nanocomposites.2. For nano LDPE films:(1) Form the UV-Vis transmittance, the high clay contents of the nano LDPE films had high visible light transmittance and ultraviolet resistance.(2) Form the measurements of the hardness, the toughness of the nano LDPE film would be increased, so reaching to extent of 3B by blown.(3) For the mechanical properties testing, we learned that adding LDPE nanocomposite film has better water blocking off, gas barrier, the tensile strength, and rupture strength.This study indicates LDPE/PE-g-MA/6% Clay nanocomposites have better mechanical properties, through blown film after 6% nano LDPE Film, by its nature is relatively increased, in addition to more uniform dispersion of clay, can improve the mechanical strength of pure LDPE does not possess the high, soft, mold shrinkage, surface hardness, disadvantages such as poor, to make this new and improved material has a high applicability.