Copolymerization in dispersion of divinyl benzene–maleic anhydride in the presence of silylated montmorillonite clays

Sodium montmorillonite (NaMMT clay) derivatives were encapsulated in polymer particles obtained through dispersion copolymerization of divinyl benzene (DVB) with maleic anhydride (MA). To evidence the effect of alkyl monoalkoxysilanes upon MMT reaction, a variety of MMT clay functional derivatives were investigated. Particles with an increased size of modified MMT clay dispersed in dichloromethane were obtained using alkyl monoalkoxysilanes with a longer hydrocarbon chain. Relatively long hydrocarbon chains can exhibit a low substitution degree of MMT clay with alkyl monoalkoxysilanes. MMT class with a low substitution degree leads in the presence of alkoxysilanes to particles with average size between 700 and 1200 nm, and when DVB–MA copolymer is added the particles size decreases (~480 nm). The influence of layered silicates on the thermal stability of DVB–MA copolymer as a function of the used vinyl siloxanes derivatives for functionalization of MMT, on one hand, and the nonlinear variation of refractive index of used silanes on the other hand, pointing out the autoassociation during initial reaction of substitution.