Synthesis of Core‐Shell Particles with Low Molecular Weight Alkanes by Miniemulsion Polymerization

Abstract

SummaryMiniemulsion polymerization technique was used to obtain core‐shell nanoparticles with a core of low molecular weight alkanes and a polystyrene shell. Reactions were performed at 80°C for 5 hours using benzoyl peroxide as oil‐soluble initiator. The effect of different alkane types, namely n‐hexadecane, n‐octane and n‐heptane, and initiator concentrations on reaction rates, particle sizes, molecular weights and particles morphology were evaluated. When shorter chain alkanes as n‐heptane and n‐octane were used it was observed lower reaction rates, higher particle sizes and less sharp particle morphology than in reactions with hexadecane in which well formed core‐shell particles were obtained. These results were assigned to the plasticizing effect and higher water‐solubility of n‐octane and n‐heptane, responsible for decreasing the gel effect and favoring the diffusional degradation.