Estimation of surface morphology of composite polymer particles prepared by the stepwise heterocoagulation method with ζ-potential measurement

Preparation of raspberry-like polymer particles by a heterocoagulation technique utilizing hydrogen bonding interactions between steric stabilizers

Large polystyrene particles stabilized by poly(acrylic acid) (PAA) (L-PS(PAA)) (as the core) and small polystyrene particles stabilized by poly(vinyl pyrrolidone) (PVP) (S-PS(PVP)) (as the corona) were successfully used to prepare raspberry-like particles by a heterocoagulation technique utilizing the hydrogen bonding interaction between PAA and PVP. The coverage of L-PS(PAA) by S-PS(PVP) could be controlled by adding PVP homopolymer to the L-PS(PAA) dispersion and by changing the molecular weight of the stabilizers. Moreover, the heterocoagulation of large poly(methyl methacrylate) particles stabilized by PAA (L-PMMA(PAA)) and S-PS(PVP) particles was also accomplished, resulting in the formation of L-PMMA(PAA)-core/S-PS(PVP)-corona raspberry-like composite particles. These results suggested that the raspberry-like particles composed of various polymer particles could be formed by the heterocoagulation technique utilizing the hydrogen bonding interaction.