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A group of heterogeneous latexes poly(butyl acrylate)/poly(styrene-co-methyl methacrylate) (PBA/P(St-co-MMA)) were prepared by a semi-continuous seeded emulsion polymerization process under monomer starved conditions. The glass transition temperature (T_g) and the mechanical properties of the film formed from the composite latex changed with the evolution of the particle morphology. A photon transmission method was used to monitor the phase structure evolution of films which were prepared from core-shell PBA/P(St-co-MMA) latex at room temperature and annealed at 383 K above T_g of the polymers. In addition, the changes of the surface of the film formed from the composite latex with time at 383 K were observed by AFM. The evidence illustrated that the film formed from the core-shell latex particles was metastable. The rearrangement of the phases could occur under proper conditions.

This paper presents a three-dimensional microfabrication and integration technology for MEMS smart materials that utilizes a spray coating method. Spray coating is shown to be most effective for additional deposition on non-planar seurfaces. PZT films were formed both on flat and uneven surfaces at a thickness of about 1 μm. Perovskite structures were formed with suitable heat treatment and ferroelectric P-E hysteresis loop was also obtained. This paper is the first report from our group and other researches on the deposition of smart materials for MEMS using a spray coating method. Spray coating has been proposed as an effective three-dimensional coating method which can be used to deposit piezoelectrics, pyroelectrics, magnetics, etc. for sensors and actuators. The hydrophilic and hydrophobic properties between the substrate surface and ejected liquid are most essential process factors in the spray coating method for improving the film growth conditions.

Polarization curve test and EIS are used to study the corrosion inhibition effect of silane modification on aluminum alloy (ADC12) in 3% NaCl. The effects of functional group of silane coupling agent, pH, and concentration have been studied. Small and polar group of silane coupling agent is benefit for the protection effect. The optimal conditions of passivation solution are pH of 1.8 and the silane coupling agents concentration of 0.8%.