Preparation of various Janus composite particles with two components differently combined

作者：Shibata Nobutaka; Nagao Daisuke; Ishii Haruyuki; Konno Mikio^*

来源：Colloid and Polymer Science, 2013, 291(1): 137-142.

DOI：10.1007/s00396-012-2687-x

• Janus particle
• Polystyrene
• Silica
• Gold
• Coupling agent
• Electroless deposition

Janus composite particles with a combination of organic and inorganic substances were synthesized by soap-free emulsion polymerization in which an amphoteric initiator of 2,2'-azobis[N-(2-carboxyethyl)-2-2-methylpropionamidine] (VA-057) was employed to introduce a polystyrene (PSt) lobe onto silica cores surface-modified with 3-methacryloxypropyltrimethoxy silane (MPTMS). Thermogravimetric analysis and X-ray photoelectron spectroscopy were used to characterize the surface-modified silica particles and showed that a small amount of MPTMS introduced onto the surface of silica particles could successfully prepare SiO2-PSt Janus particles. The oxide part of SiO2-PSt Janus particles obtained with the polymerization was further surface-modified with 3-aminopropyltriethoxysilane (APS) to introduce positively charged amino groups on the silica surface. The silica surface modified with APS was covered with gold by electroless deposition in which a gold precursor of auric chloride was reduced with ascorbic acid in the presence of polyvinylpyrrolidone. The electroless deposition of gold successfully produced Janus particles with a combination of gold and PSt surfaces. Furthermore, dissolution of the polymer component of the Au-PSt Janus particles in tetrahydrofuran led to another Janus type of particles with an inorganic combination of Au and SiO2.

• 出版日期2013-1