Surface dynamics during latex film formation

• Published in: Progress in organic coatings Vol. 40; no. 1; pp. 167 - 173
• Main Authors: Song, Mo, Hourston, Douglas J., Pang, Yongxin
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.12.2000; Elsevier Sequoia
• Subjects: Applied sciences; Atomic force microscopy; Coatings. Paints, varnishes and inks; Exact sciences and technology; Film formation and curing, properties, testing; Latex film formation; Polymer industry, paints, wood; Surface diffusion; Atomic force microscopy; Latex film formation; Surface diffusion; Coating material; Film formation; Water base paint; Experimental study; Modeling; Emulsion paint
• ISSN: 0300-9440; 1873-331X
• DOI: 10.1016/S0300-9440(00)00143-0

Surface dynamics during latex film formation has been investigated theoretically and experimentally by atomic force microscopy. The peak-to-valley distance, y( t), of the latex particles in the surface plane of the latex film decayed exponentially with time during film formation. A theoretical relationship between y( t) and time, t, is given by y(t)=y(0) exp[−t/τ] , where y(0) is the value of y( t) when t is zero. τ is a characteristic constant related to the nature of polymer, the particle radius, the surface diffusion coefficient and the temperature. The relationship between the surface diffusion coefficient, D s, y(0), the radius of the latex particles, R, temperature, T, and τ is given approximately by D s =1.2×10 −20y(0) 2[2R−y(0)] 2T /τ ( cm 2 /s) , where the units are manometers for y(0) and R, kelvin for temperature, and seconds for τ. By measuring the decay of y( t) with time, the surface diffusion coefficient can be obtained. The surface diffusion coefficient for a poly(methyl methacrylate-co-butylacrylate) (50:50) copolymer latex film was found to be A×10 −13 cm 2 /s , A is temperature-dependent.