Monodisperse Silica Particles Grafted with Concentrated Oxetane-Carrying Polymer Brushes:  Their Synthesis by Surface-Initiated Atom Transfer Radical Polymerization and Use for Fabrication of Hollow Spheres

Abstract

An oxetane group-carrying methacrylate, 3-ethyl-3-(methacryloyloxy)methyloxetane (EMO), was polymerized via copper-mediated atom transfer radical polymerization (ATRP) initiated from the surface of monodisperse silica particles (SiPs). The polymerization proceeded in a living manner producing SiPs grafted with well-defined poly(EMO) (PEMO) of target molecular weight up to about 400K with a graft density as high as 0.36 chains/nm 2 . The surface-initiated ATRP of methyl methacrylate (MMA) with PEMO-grafted SiPs as macroinitiator afforded SiPs grafted with block copolymer of the type PEMO-b-PMMA ((PEMO-b-PMMA)-SiPs). The PEMO layer of (PEMO-b-PMMA)-SiPs, located between the PMMA shell and the SiP core, was cross-linked by cationic ring-opening reaction of the oxetane groups of the EMO moieties. The removal of the SiP core of the cross-linked (PEMO-b-PMMA)-SiPs by HF etching gave polymeric hollow spheres having size uniformity and good dispersibility in organic solvents.

Modification of Cellulose by Using Atom Transfer Radical Polymerization and Ring-Opening Polymerization

“…As mentioned above, in order to achieve a better effect, the halogen exchange technique was also utilized in the polymerization processes, although the effect was not evident in our experiments. In addition, a more severe reaction conditions of bulk 29 than solvent conditions was used based on the consideration of that the reaction was the second one. The synthetic conditions and the results were summarized in Table II.…”

Preparation of Crosslinked Polymeric Nanocapsules by Surface-Initiated Self-Condensing Vinyl Polymerization on Silica Templates

“…Fukuda et al reported the ring-opening reactivity of oxetane for the shell crosslinking of the poly(3-ethyl-3-(methacryloyloxy)methyloxetane) (PEMO) grafted silica templates (740 nm) via SI-ATRP. 20 The diameter of the microcapsules obtained was about 1.5 m.…”

Temperature-responsive polymer-brush constructed on a glass substrate by atom transfer radical polymerization

“…Ten Previously the M n of the graft and free polymers produced in the same batch were found to be nearly the same [51]. Assuming that all the monomers consumed were converted to the polymer, the M n,conv value was determined from the conversion evaluated by 1 HNMR.…”