| ii Growing environmental pressures and the advent of increasingly stringent legislation concerning solvent emission have forced the coatings industry to seek the replacement of solvent-borne adhesives by all-solid coatings and/or water-borne coatings. As a consequence, there has been growing interest in, and use of, water-borne pressure-sensitive adhesives (PSAs). The properties of composite materials will be inproved by filling nano-inorganic particles in polymer matrix. So in this paper, the monodisperse silica with different diameter was prepared by St?ber method and modified byγ-methacryloxypropyl trimethoxysilane (MPS) coupling agent. Through varying the weight ratio of core and shell, the diameter of silica, the types of core, the level of CTA, and the amount of acrylic acid, the MPS-SiO2/P(n-BA-co-AA) and the silica-sol/P(n-BA-co-AA) composite latexes with different diameter were prepared through seeded semi-continuous emulsion polymerization using nano-silica as core and butyl acrylate and acrylic acid copolymer as shell. The emulsion was coated on the PET film to measure the adhesion properties. The emulsion samples were taken at every 30 minutes during the course of each latex preparation in order to determine monomer conversions and monitor the Z-average particle diameter, dz. The overall and instantaneous monomer conversions were determined by gravimetric analysis. The composition of latex particle was characterized by FTIR. The morphology of the core-shell latex particle was determined by Transmission Electron Microscopy (TEM), and the diameter and its distribution of latex were measured by TEM and the Dynamic Light Scattering (DLS). The results showed that the instantaneous and overall conversion were all high. The composite particle was with core and shell morphology and the particle diameter was controlled.Adhesion properties were assessed by peel and tack adhesion and shear resistance testing in accordance with the FINAT Test Method of 1, 8, 9 standards, and had been evaluated from dynamic mechanical properties, sol molecular, gel content, the crosslinking molecular, the entanglement molecular and so on. The results showed that the tack and 180o peel strength were related with the viscous flow of the polymer, and the gel and Mc had a great influence on the shear resistance. As for the PSAs composed with MPS-SiO2/P(n-BA-co-AA) composite particles, the tack had the lowest value and shear properties had the highest value with increasing of the amount of momomer while the peel property had a little increased; And the tack, peel and shear properties decreased with the increase of the diameter of the silica seed. For the the PSAs composed with silica-sol/P(n-BA-co-AA) composite particles, an increase in the level of chain transfer agent in the growth stage from 0.0 to 0.15% by weight to shell monomer caused tack and peel adhesion to increase and shear resistance to decrease; The effect of an increase in the level of AA in shell polymer was to increase shear resistance dramatically and led tack and peel adhesion to pass through a maximum value. When the organic soft core was insteaded by inorganic core, the shear resistance increased greatly while the tack and the peel also kept higher value.
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