Glassy core rubber particle

Core-shell rubber (CSR) particles are prepared by emulsion polymerization, and typically exhibit two or more alternating rubbery and glassy spherical layers (Lovell 1996 Chapter 8). These core-shell particles are widely used in thermoplastics, especially in acrylic materials (Lovell, 1996), and have also been used to modify thermosets, such as epoxies, cyanates, vinyl ester resins, etc. (Becu et al., 1995). 

A crosslinked rubber may be synthesized at the surface of the glass beads to produce a core-shell structure (glassy core and rubbery shell). Thermosets modified with these particles showed a strong toughening effect for an optimum thickness of the rubbery shell (Amdouni et al., 1992). 

For electrostatic and steric stabilization, the particles can be viewed effectively as colloids consisting of a soft and deformable corona surrounding a rigid core. Colloidal particles with bulk elastomeric properties are also available. These particles, which are generally of submicron size, are developed and used as reinforcement additives to improve the Impact resistance of various polymer matrices [28-30]. The rubber of choice is often a styrene/butadiene copolymer. The presence of chemical groups at the matrix-filler interface leads to improved adhesion between them. Typically, the addition of about 30% by volume of these elastomeric particles increases the impact strength of a brittle glassy polymer like polystyrene by up to a factor of 10. For some applications, particles with more complex architecture have been... 

Another type of the core-shell particles is by multilayer particles that consist of a glassy core, a thin intermediate rubber layer, and an outer glassy shell (Lovell and... 

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