聚醋酸乙烯酯樹脂奈米複材之製備與性質研究

Preparation and Characterization of Polyvinyl Acetate Resin Nanocomposites

林嘉俊(Winston Lin)

指導教授 ： 蔡宗燕

中原大學/理學院/化學研究所/碩士(2018年)

https://doi.org/10.6840/cycu201800606

摘要

研究選用天然黏土以及人工合成MgAl層狀雙氫氧化合物兩種無機層材，天然黏土以椰油醯兩性基二丙酸二鈉改質劑製成插層型黏土，以二甲基十八烷基[3-(三甲氧基矽)丙基]氯化銨-四乙氧基矽烷將天然黏土製備脫層型黏土，人工合成黏土以十二烷基硫酸鈉改質劑製備插層型人工合成無機層狀材料，並以廣角X-光繞射儀檢測黏土之層間距變化，紅外線光譜儀檢測改質劑之特徵峰與掃描式電子穿透顯微鏡檢測黏土之表面型態，再以熱重分析儀計算添加之改質劑之插層量。並以溶劑混練的方式將改質與未改質之黏土混入市售的聚醋酸乙烯酯樹脂之中，另外添加改質與未改質之黏土以原位聚合方式添加至實驗室自製之聚醋酸乙烯酯樹脂之中，用刮刀塗佈置於鋁板上製成薄膜，並比較改質與未改質黏土與兩種不同方式添加黏土對於高分子性質之影響。原位聚合方面首先以直接取樣法探討黏土對於高分子之單體轉化率得知添加黏土會使單體轉化率提高；以廣角X-光繞射儀、穿透式電子顯微鏡探討黏土在溶劑混練與原位聚合方式製成的奈米級複材之分散性以及分散型態，以熱重分析儀與微分掃瞄熱量計探討其熱性質變化，以溶劑混練方式以PVAc-CL120-K2-3.0 phr系統熱裂解溫度提升最高，可由271.14 ℃提升至291.79 ℃，玻璃轉換溫度可由6.78 ℃上升至20.50 ℃；原位聚合方式以PVAc-Mg-Al-1.0 phr-I系統提升最高熱裂解溫度由214.27 ℃提升至254.19 ℃，玻璃轉換溫度則由PVAc-CL120-2.0 phr-I提升最高可由25.35 ℃提升至33.18 ℃。以紫外光-可見光光譜儀測其穿透度檢測黏土對於高分子之透明度之影響。溶劑混練法以PVAc-Mg-Al-SDS-3.0 phr影響最為嚴重，透明度由67.4 %下降至47.1 %，原位聚合以PVAc-Mg-Al-2.0 phr-I透明度影響最大，透明度由55.3 %下降至26.7 %。並以拉伸強度探討奈米複材之機械強度，溶劑混練法中以PVAc-CL120-K2-3.0 phr奈米複材的最大拉伸強度提升效果最為明顯，由1.59 MPa提升至6.06 MPa，原位聚合以PVAc-CL120-2.0 phr-I提升最高可由5.57 MPa提升至8.12 MPa。以百格附著度測試檢測奈米複材在Epoxy鋼板上之附著強度，溶劑混練在PVAc-CL120-K2系統下可維持在有4B之附著度，而PVAc-Mg-Al-SDS系統可將附著度提升至5B，原位聚合在PVAc-CL120-I與PVAc-CL120-K2-I系統能將附著度維持在4B。在奈米複材中添加然劑進行防火檢測，溶劑混練與原位聚合分別以PVAc-CL120-DT系統以及PVAc-Mg-Al-I系統有最佳的防火效果。
藉由本研究的探討以溶劑混練法添加天然黏土與人工合成無機層材，能在不影響高分子原有之透明性、延伸率與附著度下，而有效提升高分子之熱性質、最大拉伸強度。以原位聚合法添加天然黏土與人工合成無機層材，對於高分子之透明度影響較大，延伸率也會隨著黏土添加量上升而有所下降，但在熱性質與最大拉伸強度之提升都優於溶劑混練法，在防火檢測方面則以溶劑混練之PVAc奈米複材之防火效果優於原位聚合。此外，在上述性質的提升使得PVAc樹脂在水性塗料以及黏著劑上都會有更廣泛的應用。

關鍵字

聚醋酸乙烯酯 ； 無機層狀材料 ； 水性塗料

並列摘要

In this study, there are two kinds of natural and synthetic inorganic layered materials, these layered materials were organomodified by organo modifiers, SDS (Sodium dodecyl sulfate), K2 (disodium cocoamphodipropionate), and DT-TEOS (dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride-tetraethyl orthosilicate) by ion exchange method to make organomodified layered materials. In the morphology of modified was layered materials measured by X-ray diffraction (WXRD), Scanning electron microscope (SEM) and Fourier transfer infra spectroscopy (FT-IR). The modified inorganic layered materials the intercalation amount of the modifier calculated by Thermogravimetric analysis (TGA). After successfully synthesis of inorganic nanofillers, further, these nanofillers were applied to make Polyvinyl acetate (PVAc) polymer composites by solvent casting and in situ polymerization methods. Dispersion morphology of nanocomposites confirmed by XRD, Transmission electron microscopy (TEM). Furthermore, Thermal properties investigated by TGA, Differential scanning calorimeter (DSC), respectively. Solvent casting PVAc-CL120-K2 3.0 phr nanocomposite 5 wt% weight loss temperature (T5d), glass transition temperature (Tg) increased 20.65 °C and 13.72 °C, respectively as compare to pure PVAc. While in the case of the in-situ polymerized PVAc- Mg-Al-1.0 phr-I nanocomposites maximum pyrolysis temperature 39.92 °C increased compared to pure PVAc. The effect of UV-visible properties PVAc nanocomposites investigated. Solvent casting PVAc-Mg-Al-SDS-3.0 phr nanocomposites transparency decreased from 67.4% to 47.1%, and the in-situ polymerized PVAc-Mg-Al-3.0 phr-I transparency decreased from 55.3% to 26.7%. The maximum tensile strength of solvent casting PVAc-CL120-K2-3.0 phr nanocomposites increased from 1.59 MPa to 6.06 MPa. Similarly, the maximum tensile strength of in situ polymerized PVAc-CL120-2.0 phr-I nanocomposites increased from 5.57 MPa to 8.12 MPa. Moreover, the adhesion strength of PVAc nanocomposites measured with hundred grid knife, solvent casting has 4B adhesion under PVAc-CL120-K2 system, The PVAc-Mg-Al-SDS system can increase the adhesion to 5B, and the in-situ polymerization in the PVAc-CL120-I and PVAc-CL120-K2-I systems can maintain the adhesion at 4B. Flammability of nanocomposites determined after addition of flame retardant agent. The effect of Nanofiller on flammability of solvent casting and in-situ polymerized PVAc-CL120-DT and PVAc-Mg-Al-I nanocomposites studied.
In this study, natural and synthetic inorganic layered materials were applied to make Polyvinyl acetate (PVAc) polymer composites by solvent casting can effectively increase the thermal properties and maximum tensile strength of the polymer without affecting the transparency, elongation rate and adhesion of the polymer, Adding natural and synthetic inorganic layered materials by in-situ polymerization has a great influence on thermal properties and maximum tensile strength than solvent casting, but the elongation rate will decrease with the increase of the amount of clay added, and there is a greater impact on the transparency of polymers. In the aspect of flammability, the PVAc nanocomposite with solvent casting is much better than that of in-situ polymerization. In addition, the above-mentioned improvement in properties makes PVAc resin more widely used in water-based paints and adhesives.

並列關鍵字

polyvinyl acetate ； clay ； LDH ； coating

參考文獻

[1] L. Costa, M. Avataneo, P. Bracco and V. Brunella "Char Formation in Polyvinyl Polymers I. Polyvinyl Acetate Polymer." Polym. Degrad. Stab., 77, p. 503-510, 2002.

[2] 李紅強 "黏膠原理、技術與應用". 華南理工出版社, p. 187-192 2014.

[3] Yunsheng Ding, Zhicheng Zhang, Yajun Liu, Tiejun Shi "Preparation and Characterization of Pvac/Montmorillonite Nanocomposites Initiated by Radiation Polymerization" Acta. Polym. Sin, 18, p. 504-508, 2002.

[4] M.C. Corobea, V. Uricanu, D. Donescu, C. Radovici, S. Serban, S. Garea, H. Iovu "Poly(Vinyl Acetate)–Clay Hybrids Prepared Via Emulsion Polymerization, Assisted by a Nonionic Surfactant" Materials Chemistry and Physics, 103, p. 118–126, 2007.

[5] Hui-Wang Cui, Guan-Ben Du "Preparation and Characterization of Exfoliated Nanocomposite of Polyvinyl Acetate and Montmorillonite " Chemical Engineering and Materials Science, 2(8), p. 122-128, 2011.