Preparation of core–shell attapulgite particles by redox-initiated surface reversible addition–fragmentation chain transfer polymerization via a "graft from" approach. Issue 17 (3rd February 2016)

• Record Type: Journal Article
• Authors: Yang, Haicun; Xue, Sheng; Pan, Ji; Gong, Fanghong; Pu, Hongting
• Is Part Of: RSC advances. Volume 6:Issue 17(2016)
• Page Start: 14120
• Page End: 14127
• Publication Date: 2016-02-03
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c5ra25078a
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Polymethyl methacrylate layer was grown uniformly from attapulgite by using surface-initiated reversible addition–fragmentation chain transfer polymerization via redox initiation system. Abstract : Nanoclay attapulgite (ATP) was first activated with hydrochloric acid to enhance the surface reactivity, and was then allowed to react with a synthetic aromatic tertiary amine coupling agent to introduce electron-donor groups. Subsequently, the surface-initiated reversible addition–fragmentation chain transfer (SI-RAFT) polymerization of methyl methacrylate (MMA) was carried out in the presence of a free RAFT agent cyanoisopropyl dithiobenzoate (CPDB) initiated by a redox pair made up of benzoyl peroxide (BPO) and aromatic tertiary amine functionalized ATP (ATP-ATA). The grafting process was verified by 1 H nuclear magnetic resonance, UV-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, thermo gravimetric analysis, transmission electron microscopy and gel permeation chromatography. Kinetic behavior indicated that polymerization using this redox initiation system displayed a living/controlled nature. Both the grafted and free polymers were grown in a controlled manner, and the RAFT polymerization proceeded with 37.6% monomer conversion achieved within 10 h at 50 °C, yielding about 47.4% grafting ratio of polymer relative to hybrid particles with high affinity to organic media.