In-Situ Polymerization Compatibilization

While PVOH and the vinyl acetate (co)polymers would not typically be considered to be compatible, the grafting achieved during polymerization and the resultant morphology yields useful and compatible compositions. The presence of PVOH yields good adhesion to cellulosic based substrates for wood glue, non-woven binder, and paper based packaging applications. The miscibility of PVOH with cellulose has been demonstrated, providing a rationale for the excellent adhesion [30]. 

A compatibilization technique specifically suitable for emulsion polymerization involves the in-situ polymerization of a polymer in the presence of a previously polymerized polymer. As applied to emulsion polymerization, this is typically referred to as core-shell polymerization. The procedure involves the initial polymerization of seed particles. The addition of other monomers can result in two distinct results. One result involves swelling of the monomer in the particles followed by phase separation once a critical molecular weight is achieved (if the two polymers are thermodynamically immiscible). The other result would involve the 

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