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Highlights: [•] PSA/PSi core–shell latexes synthesized through seeded emulsion polymerization. [•] Morphology characterized through TEM, DLS, and SEM-EDXS. [•] DMA analyses of the hybrid polymer show a broader effective tan δ. [•] White paints made from hybrid polymers show excellent weatherability under UV and outdoor exposure. [ABSTRACT FROM AUTHOR]

This work is focused on a facile route to prepare a new type of nylon 6-based nanocomposites with both high fracture toughness and high strength. A series of nylon 6-matrix blends were prepared via melting extrusion by compounding with poly (methyl methacrylate- co-butadiene- co-styrene) (MBS) or poly(methyl methacrylate- co-methylphenyl siloxane- co-styrene) (MSIS) latices as impact modifier and diglycidyl ether of bisphenol-A (DGEBA) as compatibilizer. Layered organic clay was also incorporated into above nylon 6 blends for the reinforcement of materials. Morphology study suggests that the MBS or MSIS latex particles could achieve a mono-dispersion in nylon 6 matrix with the aid of DGEBA, which improves the compatibilization and an interfacial adhesion between the matrix and the shell of MBS or MSIS. High impact toughness was also obtained but with a corresponding reduction in tensile strength and stiffness. A moderate amount of organic clay as reinforcing agent could gain a desirable balance between the strength, stiffness and toughness of the materials, and tensile strength and stiffness could achieve an improvement. This suggests that the combination of organic clay and core-shell latex particles is a useful strategy to optimize and enhance the properties of nylon 6. Morphology observation indicates that the layered organic clay was completely exfoliated within nylon 6 matrix. It is found that the core-shell latex particles and the clay platelets were dispersed individually in nylon 6 matrix, and no clay platelets were present in MBS or MSIS latex particles. So the presence of the clay in nylon 6 matrix does not disturb the latex particles to promote high fracture toughness via particle cavitation and subsequent matrix shear yielding, and therefore, provides maximum reinforcement to the polymer. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Abstract: Composite latex of P(St-co-BA)/P(MMA-co-BA) was prepared by two-step semi-continuous emulsion polymerization under starved conditions. Optical properties, water resistance and heat aging process of the film formed by the composite latex were examined. It was revealed that annealing temperature played an important role on the structure of the composite latex film. The surface of the film prepared at room temperature was very rough. Many micro-cracks were observed both on the surface and inside of the film. Increase of annealing temperature assisted film formation. There was a critical temperature at which the film properties, such as water resistance and transparency, were significantly improved. However, it was worth to note that phase rearrangement had occurred when the annealing temperature was higher than critical temperature. Micro-pinholes and micro-cracks were detected on the surface of the film. Meanwhile, the properties of the film, such as transparency and water adsorption, became remarkable deteriorated. [Copyright &y& Elsevier]