Comparative study on the optical, surface mechanical and wear resistant properties of transparent coatings filled with pyrogenic and colloidal silica nanoparticles

• Published in: Composites science and technology Vol. 71; no. 4; pp. 471 - 479
• Main Authors: Zhang, Hui, Tang, Longcheng, Zhou, Lingyun, Eger, Christian, Zhang, Zhong
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 28.02.2011; Elsevier
• Subjects: A. Coating; A. Nanocomposites; A. Nanoparticles; A. Polymers; Applied sciences; B. Wear; Coatings; Colloids; Composites; Dispersions; Exact sciences and technology; Forms of application and semi-finished materials; Nanoparticles; Optical properties; Polymer industry, paints, wood; Protective coatings; Silicon dioxide; Technology of polymers; Wear resistance; A. Polymers; A. Nanocomposites; B. Wear; A. Nanoparticles; A. Coating; Dispersion reinforced material; Silica; Composite material; Photopolymerization; Optical properties; Nanocomposite; Wear resistance; Polycarbonate; Coating material; Mechanical properties; Hardness; Experimental study; Gloss; Acrylate polymer; Morphology; Concentration effect; Spin-on coating; Esthetic properties; Transparent material; Colloid particle; Tribology
• ISSN: 0266-3538; 1879-1050
• DOI: 10.1016/j.compscitech.2010.12.022

We applied two kinds of silica nanoparticles, i.e. colloidal and pyrogenic ones, to improve the performance of transparent coatings on polymer substrates. The urethane–acrylate oligomer was mixed with varied concentrations of silica nanoparticles, spin-coated onto polycarbonate substrate and finally cured by ultraviolet rays. The resultant thickness of the coatings can be controlled in the range of 20–30 μm. The transmission electron microscopy revealed that both silica nanoparticles presented different dispersion states, i.e. mono-dispersion for the colloidal nanoparticles and floc-like dispersion for the pyrogenic ones. In comparison with the colloidal nanoparticles filled coatings, the pyrogenic ones exhibited much improved modulus, hardness and wear resistance, but slightly decreased optical properties such as transmittance, haze and gloss. The nanoparticle morphology, amorphous structure, dispersion state and particle–matrix interfacial bonding relating to these properties were discussed in the present study.