Mechanism for the Formation of PNIPAM/PS Core/Shell Particles

作者：Zhang Li; Daniels Eric S^*; Dimonie Victoria L; Klein Andrew

来源：Journal of Applied Polymer Science, 2014, 131(8): 40124.

DOI：10.1002/app.40124

• colloids
• emulsion polymerization
• gels
• lattices
• morphology

A multi-stage polymerization method was previously used to prepare PNIPAM/PS core/shell particles that exhibited uniform raspberry-like structures. In this current study, this polymerization process was carefully investigated in order to elucidate the PS (polystyrene) shell formation mechanism. The results indicated that the raspberry structure is due to heterocoagulation of polystyrene domains onto PNIPAM (poly(N-isopropylacrylamide)) particle surfaces. Different sizes and numbers of the PS domains can be obtained by varying the styrene feed rate. It was also found that linear PNIPAM may increase the compatibility between PNIPAM and PS polymers. In addition, this heterocoagulation mechanism for forming structured particles was successfully applied to a PNIPAM and Ludox((R)) colloidal silica nanoparticle system where a core/shell structure was also obtained.

• 出版日期2014-4-15