Preparation of Thermo-Responsive and Cross-Linked Fluorinated Nanoparticles via RAFT-Mediated Aqueous Polymerization in Nanoreactors

Abstract

In this work, a thermo-responsive and cross-linked fluoropolymer poly(2,2,2-Trifluoroethyl) methacrylate (PTFEMA) was successfully prepared by reversible addition-fragmentation chain transfer (RAFT) mediated aqueous polymerization with a thermo-responsive diblock poly(dimethylacrylamide-b-N-isopropylacrylamide) (PDMA-b-PNIPAM) that performed a dual function as both a nanoreactor and macro-RAFT agent. The cross-linked polymer particles proved to be in a spherical-like structure of about 50 nm in diameter and with a relatively narrow particle size distribution. 1H-NMR and 19F-NMR spectra showed that thermo-responsive diblock P(DMA-b-NIPAM) and cross-linked PTFEMA particles were successfully synthesized. Influence of the amount of ammonium persulfate (APS), the molar ratio of monomers to RAFT agent, influence of the amount of cross-linker on aqueous polymerization and thermo-responsive characterization of the particles are investigated. Monomer conversion increased from 44% to 94% with increasing the molar ratio of APS and P(DMA-b-NIPAM) from 1:9 to1:3. As the reaction proceeded, the particle size increased from 29 to 49 nm due to the consumption of TFEMA monomer. The size of cross-linked nanoparticles sharply decreased from 50.3 to 40.5 nm over the temperature range 14–44 °C, suggesting good temperature sensitivity for these nanoparticles.

Surface functionalisation of poly-APO-b-polyol ester cross-linked copolymers as core–shell nanoparticles for targeted breast cancer therapy

“…The use of the radiation-induced RAFT polymerisation approach for synthesising the copolymer nanoparticles in the present study can be claimed as safe, conducted in a controllable process at room temperature, faster, and involved no catalyst to perform the reaction compared to the thermal method and/ or other C/LRP methods such as the NMP process that requires the presence of both high-temperature reaction and ATRP-based catalyst 26 . Furthermore, the application of gamma radiation as a tool in RAFT polymerization is a promising initiation source for the formation of copolymer nanoparticles with a defined molecular weight and narrow molecular weight distribution (see Table 1 ) 8 , 10 , 27 .…”

Preparation of fluoropolymer materials with different porous morphologies by an emulsion template method using supercritical carbon dioxide as a medium

“…In addition there is no undesired metal species introduced during RAFT polymerization process. 31 Truong et al 32,33 synthesized thermo-responsive copolymer P(DEGMA-co-HPMA), then they described its application in the RAFT-mediated emulsion polymerization of styrene in order to produce nanoparticles with tuneable morphology.…”

Methyl Methacrylate HIPE Solely Stabilized by Fluorinated Di‐block Copolymer for Fabrication of Highly Porous and Interconnected Polymer Monoliths

“…Moreover, a variety of functional monomers, solvents and initiators are compatible with RAFT polymerization. These advantages render RAFT polymerization as a very suitable method for the synthesis of a wide range of block copolymers with desired properties . The copolymers include poly(4‐vinylpyridine)‐ b ‐poly(ethylene glycol)‐ b ‐poly(4‐vinylpyridine), poly(ethylene oxide)‐ b ‐poly(styrene) and poly(styrene)‐ b ‐(acrylic acid) along with extended research in this field …”