Preparation of crosslinked temperature-responsive polymer networksat the surface of silica nanoparticles

In this study, temperature-sensitive poly(N-isopropylacrylamide) nanocapsules were prepared byperception polymerization of N-isopropylacrylamide with different densities of N,N-methylene-bisacrylamide (MBA) as crosslinker in the presence of silica nanoparticles. After silica removal, therelevant nanocapsules were also prepared. Surface modification of the silica nanoparticles with differentamounts of ۳-(trimethoxysilyl) propyl methacrylate (MPS) was characterized by the FTIR. The FTIRresults for hollow nanocapsules showed that complete elimination of silica nanoparticles was notcompleted. TEM showed the hollow structure of the hybrid nanocapsules. Temperature-responsivebehaviour of the nanohybrids and nanocapsules was evaluated using UV-Vis spectroscopy. The resultsshowed that UV-Vis adsorption intensity was increased with increasing MPS and MBA density andLCST occurs at lower temperatures. Also, hollow nanocapsules showed higher swelling compared tohybrid nanocapsules.

کلیدواژه ها:

Temperature-responsivity ، Poly(N-isopropylacrylamide) ، Nanocapsules ، Hybrid and hollowparticles ، Smart polymers.