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

Abstract

We developed a process to fabricate crosslinked polymeric nanocapsules with about 10-40 nm hollow cores. These crosslinked polymeric nanocapsules were fabricated via the surface-initiated self-condensing vinyl polymerization (SI-SCVP) of p-chloromethyl styrene (CMS) from initiator modified silica nanoparticles with atom transfer radical polymerization (ATRP) technique. The silica templates were removed by HF etching to produce the crosslinked polymeric nanocapsules after the grafted hyperbranched polymers had been crosslinked. Transmission electron microscopy (TEM) was used to characterize the products and to demonstrate that the polymeric nanospheres were hollow. FTIR spectroscopy showed that the silica templates were completely removed by etching.

Design of Controllable-structured Polymeric Nanocapsules via SI-ATRP from Colloidal Templates

“…Mu et al developed a novel process to fabricate the crosslinked polymeric nanocapsules with about 10-40 nm hollow cores, via the surface-initiated self-condensing vinyl polymerization (SI-SCVP) of p-chloromethyl styrene (CMS) from initiator modified silica nanoparticles with ATRP technique [58]. In order to enhance the reacting activity, the benzyl chloride end groups were transformed to amino end groups by the sequential treating with NaN 3 and LiAlH 4 .…”

“…Compared with the chemical crosslinked approach, no crosslinker was needed in the proposed SI-ATRP/photo-crosslinking technique. So it could avoid the pollution from the small organic crosslinker such as HDI [58,60].…”

Biocompatible and Biodegradable Polymeric Nanocapsules from Poly(α,β-malic acid)-Grafted Nano-silica Templates

“…The cross-linking of poly(α,β-malic acid)-grafted silica nanoparticles was conducted using similar procedures as in our previous research [32]. The procedures are as follows: 0.015 g glycerol, 0.23 ml DIC and 0.2 g HOBt were added to a suspension of the poly(α,β-malic acid)-grafted silica nanoparticles (0.45 g) in anhydrous DMF (100 ml) at 40 • C under electromagnetic stirring for 24 h. The cross-linked core/shell nanoparticles were washed with ethanol and dried under vacuum for 24 h.…”

“…While etching the silica templates, the similar procedures were used as in our previous research [32]. A suspension of the cross-linked core/shell particles (0.3 g) in ethanol was added to HF (3 ml).…”

Preparation of Photo-Sensitive Degradable Polymeric Nanocapsules from Dendrimer Grafted Nano-Silica Templates

“…While etching the silica templates, the same procedures were used exactly as our previous research (21). 3 mL hydrofluoric acid was added into a DMF suspension of the cross-linked particles (0.3 g).…”