以乳化聚合法製備改質型黏土/ 壓克力樹脂奈米複材及其性質探討

Preparation and Characterization of Poly(methylmethacrylate) /Modified Clay Nanocomposites by Emulsion polymerization

劉于脩(Liu Yuxiu)

指導教授 ： 蔡宗燕

中原大學/理學院/化學系/碩士(2022年)

https://doi.org/10.6840/cycu202201642

摘要

本研究以乳化聚合法合成聚甲基丙烯酸甲酯/改質型黏土奈米級複合材料探討其不同改質型黏土對奈米複材之機械性質、熱性質及光學性質等影響。天然蒙脫土進行有機化改質，其改質目的是提升無機層材與高分子基材的相容性，利用 X 光繞射儀（X-ray Diffraction, XRD）觀察無機層材之層間距變化，傅立葉轉換紅外線光譜儀（Fourier Transform Infrared, FT-IR）鑑定改質蒙脫土層間之有機與無機的官能基，證明有機改質劑的長碳鏈存在無機層材的層間或表面。以熱重分析儀（Thermogravimetry Analyzer, TGA）定量分析改質蒙脫土中改質劑的插層量，並了解其熱穩定性。
以不同的天然黏土與改質劑合成的改質土( CL120-CPB、CL120-CPS、CL88-CPB、CL88-CPS )進行乳化聚合法製備聚甲基丙烯酸甲酯/黏土奈米級複合材料。以 XRD 及穿透式電子顯微鏡（Transmission electron microscopy, TEM）觀察其分散性，而以四種有機改質型黏土製備奈米複材中，3 phr的添加量為部份脫層部份插層之分散型態；其熱裂解溫度（Decomposed temperature, T5d）最高提升 28℃，自 294.2℃提高至322.5℃，而 EP-CL88-CPS-5 phr其玻璃轉移溫度（Glass transition temperature, Tg）提升7℃，自120℃提高至 127 ℃； 在光學性質方面，添加5 phr黏土後其複材的穿透度均可在94%以上，而EP-CL88-CPS-5 phr其紫外光吸收能力最好，與純的聚甲基丙烯酸甲酯相比，當波長為 320 nm 時，降低約25%，自 86%降低至61%；在機械性質方面，EP-CL88-CPB-5 phr其儲存模數提高，從 1872 MPa 增加至2857 Mpa(提升了52.6%)，鉛筆硬度方面，純的聚甲基丙烯酸甲酯鉛筆硬度為 2H-3H，而EP-CL88-CPB-3 phr和EP-CL88-CPS-3 phr 其鉛筆硬度自2H-3H 提升達到4H-5H；在耐磨耗性方面，EP-CL88-CPS-3 phr和EP-CL88-CPB-3 phr重量損失最少，耐磨耗性最好，在老化測試方面，經照紫外光波長375 nm，2小時，前後儲存模數比較，EP-CL88-CPS-3 phr對紫外光的阻隔最好，衰退比從35％下降至13％，在氣體阻隔方面，以CL88-CPS-3 phr分散性最好，氧氣阻氣性自0.8733 barrer 降至0.2784 barrer，改善68.1％，氮氣阻氣性自0.7764 barrer 降至0.1426 barrer，改善81.6％，氧氣與氮氣之 BIF值分別為3.13和5.44倍。
故本論文發表，從文獻與專利報導中，超越其機械性質，紫外光阻抗，耐候性與表面硬度的同步提升。

關鍵字

聚甲基丙烯酸甲酯 ； 天然黏土 ； 奈米複材 ； 乳化聚合

並列摘要

In this study, polymethyl methacrylate/modified clay nanocomposites were synthesized by emulsion polymerization method to investigate the effects of different modified clays on the thermal, mechanical, and optical properties of nanocomposites. The organic modification has improved the compatibility of inorganic layered materials and polymer substrates. Clay modification and modifier amount quantitatively analyzed by X-ray diffraction (XRD) and thermogravimetry analyzer (TGA), respectively. Furthermore, Fourier Transform Infrared (FT-IR) was used to identify the organic and inorganic functional groups between the layers of the modified montmorillonite.
Polymethylmethacrylate (EPMMA)/modified clay were prepared by emulsion polymerization with four types of modified clays (CL120-CPB, CL120-CPS, CL88-CPB, CL88-CPS) with different phr (1, 3 and 5 phr) loading. The dispersibility of CL120-CPB, CL120-CPS, CL88-CPB and CL88-CPS nanocomposites were observed by XRD and Transmission electron microscopy (TEM). The EPMMA/ modified clay-3 phr performed the partial delaminated apart and partial intercalated nanocomposites in the nanocomposite matrix observed. Their thermal cracking temperature (Decomposition temperature, T5d) increased the most by 28 °C, from 294.2 °C to 322.5 °C, while the glass transition temperature (Tg) of EP-CL88-CPS-5 phr increased by 7 °C, from 120 °C to 127 °C. In terms of optical properties, in the visible light range (550 nm) the nanocomposite 5 phr modified clay loaded samples % transmission (%T) above 94%. In the wavelength 320 nm %T is reduced 25%. The mechanical properties, EP-CL88-CPB-5 phr, which performed the best storage modulus, has increased from 1872 MPa to 2857 MPa (increasing of 52.6%). The pencil hardness of pure EPMMA pencil hardness is 2H-3H, while the pencil hardness of EP-CL88-CPB-3 phr and CL88-CPS-3 phr are increased to 4H-5H. Furthermore, the wear test, EP-CL88-CPS-3 phr and EP-CL88-CPB-3 phr have the least weight loss during the abrasion test, For the aging test, compared with the storage modulus of EP-CL88-CPS-5 phr, which were irradiated at 375 nm for 2 h were reduced ratio from 35% to 15%. In terms of gas barrier, CL88-CPS-3 phr has the best phr dispersion, the oxygen gas barrier property is reduced from 0.8733 barrer to 0.2784 barrer, an improvement of 68.1%, and the nitrogen gas barrier property is reduced from 0.7764 barrer to 0.1426 barrer, an improvement of 81.6%. BIF of oxygen and nitrogen are increased by 3.13 and 5.44 times, respectively.
From this work it is concluded that surpasses EPMMA composites mechanical properties, UV light resistance, weather resistance and surface hardness.

並列關鍵字

poly methyl methacrylate ； clay ； nanocomposites ； emulsion polymerization

參考文獻

[1] B. T. W. Caspary, "Der Β -Biprompropionsäure in Acrylsäure", Ann, vol. 167, pp. 241-242, 1873.

[2] R. Fittig, "Ueber Polymerisirte Ungesättigte Säuren", Juli–Dezember, vol. 12(2), pp. 1739-1744, 1879.

[3] W. F. Smith, "Foundations of Materials Science and Engineering 4th Ed", McGraw-Hill, pp. 509-510, 2006.

[4] J. A. B. 著. 范啟明譯, 塑膠材料, 大中國圖書公司, 1989.

[5] F. W. L. Gucker Frank T. Jr., "Specific Heat of Lucite (Methyl Methacrylate Polymer) ", J. Am. Chem. Soc, vol. 60, pp. 2563-2563, 1938.