Preparation and characterization of dual-responsive spiropyran-based random copolymer brushes via surface-initiated atom transfer radical polymerization

Abstract

(2016) Preparation and characterization of dual-responsive spiropyran-based random copolymer brushes via surfaceinitiated atom transfer radical polymerization, Designed Monomers and Polymers, 19:2, 193-204, DOI: 10.1080/15685551.2015 shenzhen institutes of advanced Technology, Chinese academy of sciences, shenzhen, P.r. China ABSTRACT Silica nanoparticles (SiO 2 ) were grafted with the precursor random copolymer of 1′-(2-acryloxyethyl)-3′,3′-dimethyl-6-nitrospiro-(2H-1-benzopyran-2,2′-indoline) (SPMA) and tert-butyl methacrylate (tBMA) by surface-initiated atom transfer radical polymerization (SI-ATRP), and SiO 2 -g-P(SPMA-comethacrylic acid (MAA)) was obtained via chemical hydrolysis of the resulting precursor random copolymer in acidic conditions. From transmission electron microscopy, we observed the spherical morphology of monodispersed silica nanoparticles and core-shell structure of SiO 2 -g-P(SPMAco-MAA). Energy dispersive spectroscopy, Fourier transform infrared spectra, X-ray photoelectron spectroscopy, and the thermogravimetric analysis indicated that the polymer had been successfully grafted onto the surface of silica nanoparticles. The dual-responsive properties were characterized by means of ultraviolet-visible spectrophotometer and dynamic light scattering. The average hydrodynamic diameter of SiO 2 -g-P(SPMA-co-MAA) increased from 185.7 to 212.7 nm under ultraviolet light irradiation for 5 min. Also, the particle size of SiO 2 -g-P(SPMA-co-MAA) increased with the rising pH value of surrounding condition.

Photo‐ and pH‐Responsive Hybrid Colloidal Particles

“…So far, the ATRP method has been frequently used for the synthesis of SP‐containing photochromic hybrid colloids [25–27] . It is based on a redox process, catalyzed by a transition metal complex.…”

“…[24] So far, the ATRP method has been frequently used for the synthesis of SP-containing photochromic hybrid colloids. [25][26][27] It is based on a redox process, catalyzed by a transition metal complex. Residual catalyst is a notable disadvantage of ATRP because of high cost of its removal and toxicity of the final polymer.…”

Formation of activation‐free, selectively bioconjugatable poly(N‐acryloxysuccinimide‐co‐oligoethylene glycol methyl ether methacrylate) films by surface‐initiated ARGET ATRP

“…Traditional ATRP is one of most useful methods for controlled/living radical polymerization, and SI‐ATRP has been used to develop surfaces with various functionalities such as anti‐biofouling, anti‐bacterial effects, and light/pH responsibility . However, the traditional ATRP requires the use of deoxygenated solvents and inert environment during polymerization.…”