Preparation of sol-gel based nano-structured hybrid coatings: effects of combined precursor%26apos;s mixtures on coatings morphological and mechanical properties

作者：Ramezanzadeh B; Mohseni M^*

来源：Journal of Sol-Gel Science and Technology, 2012, 64(1): 232-244.

DOI：10.1007/s10971-012-2852-1

• Sol-gel
• Hybrid clearcoat
• TEOS
• MEMO
• Nanoindentation
• SEM
• DMTA

Nanostructured hybrid clearcoats were produced using sol-gel based organic/inorganic precursors. To this end, clearcoats containing mixtures of a network former (tetraethyl ortosilicate; TEOS) and a network modifier (methacryloxy propyltrimethoxysilane; MEMO) and their hydrolyzed forms were prepared. Scanning electron microscope and atomic force microscope were utilized in order to investigate the morphology of different sol-gel prepared films. The mechanical properties of the bulk and surface of the clearcoats were studied by dynamic mechanical thermal analysis and nanoindentation techniques. The scratch resistance of the hybrid clearcoats was also studied by a laboratory carwash simulator. Decrease in glass transition temperature (Tg), cross-linking density, hardness and elastic modulus were seen for the clearcoat composed of hydrolyzed network modifier combined with hydrolyzed and non-hydrolyzed network former. However, a reverse effect was seen when the hydrolyzed TEOS and non-hydrolyzed MEMO was used. No improvement was observed using hydrolyzed MEMO in the clearcoat composition. Generally, results revealed improved mechanical properties of the clearcoat when the hydrolyzed network former was used together with non-hydrolyzed MEMO. Greater phase separation and silica cluster formation were seen for the clearcoats loaded with hydrolyzed MEMO compared with hydrolyzed TEOS.

• 出版日期2012-10