奈米化無機層材以雙螺桿混練製備聚烯烴奈米複材之開發與性質探討

Study on the Preparation and Characterization of Inorganic Layered Materials Nanohybrid Polyolefin by Twin Screw Process

葉建麟(Chien-Lin Yeh)

指導教授 ： 蔡宗燕

中原大學/理學院/化學研究所/碩士(2013年)

https://doi.org/10.6840/CYCU.2013.00438

摘要

本研究選用天然純化蒙脫土(Clay)與人工合成鎂鋁層狀雙氫氧化合物(MgAl LDH)兩種層狀材料，其中天然黏土利用溶膠-凝膠法(Sol-gel)進行表面改質，由結果顯示，在未添加於高分子基材前已經可以先行將天然黏土達到一定程度上的脫層結構；藉由共沉澱法(Coprecipitation method)與水熱法(Hydrothermal method)方式合成鎂鋁層狀雙氫氧化合物，並利用層間離子置換法(Ion Exchange method)插層(Intercalated)有機改質劑進行表面改質。並分別將表面改質的層狀材料，利用微型雙螺桿熔融試驗機與市售之聚乙烯與聚丙烯製備成聚烯烴奈米複材，並以熱壓方式製備薄膜進而評估其各項性質。結果顯示，聚乙烯奈米複材之拉伸強度最高可提升18.2 %；複材耐熱性之熱裂解溫度可以提升31 ℃；而阻氣性質的方面，氧氣最高可以提升1.44倍，氮氣部分可以提升1.99倍；光學性質部分，透明度依舊保持良好，可降低UVA的穿透23.6 %、UVB可降低23.8 %、UVC可降低21.1 %。聚丙烯奈米複合材料拉伸強度可提升57.8 %；複材耐熱性之熱裂解溫度可以提升8.0 ℃；而阻氣性質的部分，氧氣最高可以提升1.57倍，氮氣部分可以提升1.56倍；光學性質部分，可降低UVA的穿透7.7 %、UVB可降低10.2 %、UVC可降低7.9 %。
本研究後半進行放大製程的評估，選用人工合成鎂鋁層狀雙氫氧化合物進行放大生產，利用共沉澱法與水熱法直接一步合成與改質鎂鋁人工層材，製備大倍量之改質型人工層狀雙氫氧化合物，將其以2 phr添加量分別添加於聚乙烯和聚丙烯，經小型雙螺桿熔融混練後再利用擠壓吹膜的方式製備出吹袋型奈米複合材料，並探討其性質與應用性。結果顯示，吹袋型聚乙烯奈米複合材料，其機械性質在縱向(Machine Direction，MD)楊氏系數可以提升24.3 %、橫向(Transverse Direction，TD)提升28.0 %；複材之熱裂解溫度可以提升15.7 ℃；阻氣性質部分，氧氣阻隔可以提升1.46倍、氮氣阻隔可以提升1.41倍。吹袋型聚丙烯奈米複合材料，複材之熱裂解溫度可以提升11.7 ℃；阻氣性質部分，氧氣阻隔可以提升1.30倍、氮氣阻隔可以提升1.29倍。

關鍵字

奈米複材 ； 天然黏土 ； 聚乙烯 ； 人工層狀雙氫氧化合物 ； 聚丙烯 ； 雙螺桿混練 ； 擠壓吹膜

並列摘要

In this study, there are two types of inorganic layered materials, applied as nano-fillers, pristine sodium montmorillonite clay and MgAl-layer double hydroxide (MgAl LDH). Pristine sodium montmorillonite clay was modified by sol-gel process, and layer double hydroxide was modified by coprecipitation treatment and hydrothermal method. The characteristics of modified layered materials were identified by wide angle X-ray diffraction (WAXRD) for the d-spacing of the montmorillonite and scanning electron microscope (SEM) for the surface morphology of these inorganic materials. The results show that modified layered materials had achieved partially exfoliated before melt blending with polymer. On the other hand, the characteristics of modified LDHs were identified by WAXRD for the d-spacing, Fourier transform infrared (FTIR) for the organic modifier of LDH functional groups. There are two kinds of surface modified layered materials separately applied to polymer nanocomposites using by twin screw micro-compounder with polyethylene (PE) and polypropylene (PP), and then made thin film of polymer nanocomposites by hot pressure method. In PE nanocomposites, the results show that tensile stress was increased 18.2% due to the exfoliated nanostructure of layered materials. The T5d was increased 31 ℃, and the gas permeability was effectively reduced, the barrier improvement factor (BIF) was increased 1.44 in oxygen, and increased 1.99 in nitrogen. The PE nanocomposites show a slight decline in transmission in the visible light region as content increased but retained an optical transmission. The resistances of ultraviolet A (UVA), ultraviolet B (UVB) and ultraviolet C (UVC) were decreased 23.6%, 23.8% and 21.1%, respectively. In PP nanocomposites, the tensile stress and T5d are increased 57.8% and 8 ℃, respectively. The BIF of gas permeability is increased to 1.57 in oxygen, and increased to 1.56 in nitrogen. The PP nanocomposites still had good transmission in the visible light region but reduced UV transmission. The UVA resistance was decreased 7.7%, UVB 10.2%, and UVC 7.9%, compared with pristine resin.
Finally, the scale-up processing has been studied after the microcompounder’s work. The synthesis and the characterization of polyolefin/MgAl LDH-SDBS nanocomposites have been evaluated. The layered material MgAl LDH-SDBS was made from MgAl LDH with Sodium dodecyl benzene sulfonate (SDBS) by one-step coprecipitation method and hydrothermal method. Polyolefin/MgAl LDH-SDBS nanocomposites were prepared by twin screw process, followed by compounding, and then blown into films using a single-screw extruder. The mechanical properties of PE/MgAl LDH-SDBS nanocomposites show that Young’ modulus is increased 24.3% in machine direction (MD), and 28.0% in transverse direction (TD). The T5d is increased 15.7 ℃. The BIF of gas permeability is increased to 1.46 in oxygen, and 1.41 in nitrogen. For PP/MgAl LDH-SDBS nanocomposites , the T5d is increased 11.7 ℃. The BIF of gas permeability is increased to 1.30 in oxygen and 1.29 in nitrogen.

並列關鍵字

blowing film ； twin screw ； PP ； Clay ； PE ； Nanocomposites ； LDH

參考文獻

29. 陳均偉，“聚丙烯/改質蒙脫土奈米複材製備與物性”，碩士學位論文，中興大學化工系，2008。

33. 曾子凡，“製備主客型黏土/二氧化矽奈米混成材料及其聚苯乙烯奈米複合材料與物性分析”，博士學位論文，中興大學化工系，2010。

34. 梁智凱，“蒙脫土奈米複合材料之製備及其在燃料電池與銅箔基板上之應用”，碩士學位論文，中原大學化學系，2012。

3. C. E. Weaver, L. D. Pollard, " The chemistry of clay minerals ", Elsevier Sci. Publ. Co., 1973, p137-144.

4. A.Usuki, M. Kawasumi, Y. Kojima, A. Okada, T. Kurauchi, "Swelling behavior of montmorillonite cation exchanged for ω-amino acids by ε-caprolactam", J. Mater.Res., 1993, 8, 1174-1178.