Preparation of Thermosensitive PNIPAm-Grafted Mesoporous Silica Particles

• Published in: Macromolecular chemistry and physics Vol. 208; no. 22; pp. 2419 - 2427
• Main Authors: Park, Jun-Hwan, Lee, Young-Ho, Oh, Seong-Geun
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 20.11.2007; WILEY‐VCH Verlag; Wiley
• Subjects: Applied sciences; Composites; emulsion-gel method; Exact sciences and technology; Forms of application and semi-finished materials; PNIPAm; Polymer industry, paints, wood; radical polymerization; silicas; Technology of polymers; thermoresponsive; PNIPAm; Water oil emulsion; Surface reaction; Thermal transition; Acrylamide derivative copolymer; Nanoporous materials; Experimental study; Silicon copolymer; Silica; Thermal stability; radical polymerization; Crosslinked copolymer; Pore size; thermoresponsive; Sol gel process; Morphology; Preparation; emulsion-gel method; Microparticle; Methacrylate copolymer; Surface area; Radical copolymerization; silicas; Graft polymers
• ISSN: 1022-1352; 1521-3935
• DOI: 10.1002/macp.200700247

In this study, the composites of thermoresponsive poly(N‐isopropylacrylamide) (PNIPAm) and mesoporous silica particles were synthesized. 3‐(Trimethoxysilyl)propyl methacrylate (MOP) was used to introduce double bonds on silica particles. First, MOP‐modified spherical silica particles were prepared by the sequential addition of tetraethyl orthosilicate (TEOS) and MOP into W/O (water‐in‐oil) emulsion. Second, PNIPAm‐grafted silica microparticles were synthesized by the radical copolymerization of MOP‐modified silica particles and N‐isopropylacrylamide (NIPAm) monomers in the ethanol/water mixture. Polymerization was carried out with the variation of reaction temperature, concentration of crosslinking agent, and weight ratio of MOP‐modified silica particles to NIPAm monomers. The formations of MOP‐functionalized silica microspheres and PNIPAm‐grafted silica microparticles were characterized by FE‐SEM, TEM, FT‐IR, TGA, and BET. The lower critical solution temperature (LCST) of the PNIPAm‐grafted silica particles was investigated by DSC.