Preparation and Physical Properties of Polyacrylate/Laponite/Silica Nanocomposites Film by UV Photopolymerization

• Main Authors: Ping-Shung Chen, 陳秉昇
• Other Authors: Jeng-Yue Wu
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/95267p

碩士 === 國立中興大學 === 化學工程學系所 === 107 === In this study, Laponite was modified to improve dispersibility in monomer, and prepared nanocomposite films by UV polymerization. First, we dispersed Laponite into water, and added ‎3-Aminopropyl triethoxysilane (APS) at acidic condition. APS was absorbed on Laponite by ion exchange with Na cation on Laponite surface, then we put silica particles on laponite made by TEOS. Silica particles were grafted on Laponite surface by reacting with alkoxy silane group on APS, then we got Laponite/silica hybrid (ALS). Subsequently, we added MPS which will graft on silica, bearing the C=C group, and changed surface property from hydrophilic into lipophilic. Finally, we added monomer methylmethacrylate (MMA) and initiator potassium persulfate (KPS), and polymerized PMMA on Laponite surface by emulsifier-free polymerization to obtain modified Laponite (ALS-MP-4M, ML). The lipophilic polymer grafted on Laponite can promote dispersibility in monomer. In this study, we used the monomer HDDA, HDDA/BA, HDDA/TAEI to prepared nonacomposite film. HDDA had two C=C groups. BA has one C=C group. We added BA into HDDA to reduce the cross-linking degree, and make film softer. TAEI has three C=C groups.We added TAEI into HDDA, and made film harder. The modified Laponite and acrylic monomers nanocomposites film were prepared by UV polymerization. From the result of pencil hardness analysis, when the content of modified Laponite was increased from 0% to 3%, the pencil hardness of the PHDDA nanocomposites film was increased from 6H to 9H. From the result of UV-Vis transmittance analysis, when the content of modified Laponite was increased from 0% to 3%, the transmittance of the P1B4H nanocomposites film was decreased from 97.6% to 94.7%. From the result of water and ethylene glycol contact angle analysis for the calculation the surface energies by Owens-Wendt-Rabel-Kaelble (OWRK) method, with increase of the content of modified Laponite (ML), the polar part surface energy of the nanocomposite film was decreased. the dispersion part surface energy of the nanocomposite film was independence of the content of modified Laponite.