Cross-linking of Grafted Copolymer on Colloidal Silica and Introduction of Surface Amino Group

Abstract

ABSTRACT:To obtain polymer-modified silica (550 nm diameter), trimethoxysilyl-terminated poly(glycidyl methacrylate-co-methyl methacrylate) with epoxy ring (to prevent the formation of carboxyl group) was successfully synthesized. Then, the cross-linking of the grafted copolymer on silica was made using ethylenediamine or hexamethylenediamine of varying alkyl chain lengths, and the stability of cross-linked silica particles was investigated in alkaline aqueous solution. Cross-linked polymer-modified silica based on diamines exhibited much lower reduction rate (in wt %) of the attached polymer to silica than uncross-linked polymer-modified silica. In particular, cross-linked silica composites by ethylenediamine had more stability than cross-linked silica composites by hexamethylenediamine. Finally, the cross-linking reaction of grafted-polymer on silica particles by diamines was confirmed by the 13 C CP/ MAS NMR spectra measured on polymer-modified silica composites.

Thermal properties of TRIM–GMA copolymers with pendant amine groups

“…The presence of epoxy groups allows a number of chemical modifications on the initial polymer to suit a variety of applications. Consequently, preparation of GMA-based copolymers and their modifications is the subject of numerous papers [10][11][12][13][14][15][16][17][18][19][20][21][22]. The conducted studies had indicated that an amine group is one of the most efficient functional groups for heavy metal ion removal.…”

Structure, Thermal, and Morphological Properties of Novel Macroporous Amino-Functionalized Glycidyl Methacrylate Based Copolymers

“…The 13 C MAS NMR spectrum of homopolymer poly-GMA, presented in Figure a, shows resonance peaks at 16 ppm for 3 ( C H 3 −), 55 ppm for 1 (H 2 C CCH 3 COCH 2 ), 45 ppm for 2 (H 2 C C CH 3 COCH 2 ), 67 ppm for 5 (−O– C H 2 −), and 177 ppm for 4 (−O­( C O)­C−) . The resonance peaks of 6 at 49 ppm and 7 at 44 ppm were assignable to CH and CH 2 of the epoxy ring.…”

“…13 C MAS NMR spectra of homopolymers, poly­(glycidyl methacrylate) (poly-GMA), poly­(ethylene glycol dimethacrylate) (poly-EGDMA), and initial copolymers poly­(GMA- co -EGDMA) with 60 and 80 mass % of GMA are presented in Figures a,b,c and S1 (Supporting Information), respectively. The assignments of the NMR resonance signals have been made by comparison with spectra of analogous chemical groups taken from the previously reported investigation. − …”