Grafted polysaccharides based on acrylamide and N,N‐dimethylacrylamide: Preparation and investigation of their flocculation performances

Abstract

The graft copolymerization of N,N-dimethylacrylamide (DMA) and acrylamide (AM) were carried out onto different polysaccharide backbones separately. The graft copolymers were synthesized by ceric ion induced redox polymerization technique. Three polysaccharides were used, namely hydroxyethyl starch (HES), hydroxyethyl cellulose (HEC) and Amylopectin (AP), for the grafting reactions. Among the three polysaccharides, HEC has linear structure, while HES and AP have a branch one. The graft copolymers were characterized by intrinsic viscosity measurements, FTIR spectroscopy, NMR (both 1 H and 13 C) spectroscopy, and thermal analysis. Flocculation performances of the graft copolymers were evaluated in 1 wt % kaolin and in 0.25 wt % iron ore suspensions. A detailed comparative study of the flocculation properties of the synthetic graft copolymers was also made. It showed that graft copolymers based on DMA were better flocculants than those based on AM. Among the synthetic graft copolymers, HES-g-Poly (DMA) performed best when compared with the other synthetic graft copolymers as well as to the commercial flocculants in the same suspensions.

Synthesis and characterization of a pH-responsive poly(ethylene glycol)-based hydrogel: acid degradation, equilibrium swelling, and absorption kinetic characteristics

“…Both of them were corresponded to GMA PEG structure [29]. In the same spectra, the signals at δ 45 and 37 ppm were assigned to carbons in the main chain of the hydrogel network (CH and CH 2 , respectively) [30,31]. Moreover, side band spinning effect (*) was associated with signals at δ 235 and δ 119, which are symmetric to the carbonyl group at δ 178 [32,33].…”

Green synthesis, characterization and antibacterial activity of gold nanoparticles using hydroxyethyl starch-g-poly (methylacrylate-co-sodium acrylate): A novel biodegradable graft copolymer

“…A broad strong signal at 3428 cm −1 is for\ \OH groups present in the polysaccharide backbone and the peak at 2926 cm −1 is for the saturated 'C\ \H' units in the macromolecule. The FTIR spectrum of HES was given in our previous report [32]. The 1 H NMR spectrum is shown in Fig.…”

Synthesis and flocculation characteristics of a novel biodegradable flocculating agent amylopectin-g-poly(acrylamide-co-N-methylacrylamide)

“…However, PAM based graft copolymers have a problem of water solubility. It has been observed in the authors' laboratory that by grafting poly N,N-dimethylarylamide (PDMA) chains onto various polysaccharides like Hydroxyethyl starch (HES) [20], Amylopectin (AP) [21] and Hydroxyethyl cellulose (HEC) [22], it is possible to develop flocculating agents which are readily water soluble and showed better performance than PAM grafted polysaccharides into aqueous suspensions of kaolin clay, iron ore slimes, silica etc. The better flocculating properties of PDMA grafted polysaccharides into various aqueous suspensions are explained by the following way.…”

“…Turbidity measurements were carried out with a digital nephelo turbidity meter (Model-33, E1 products, Haryana, India). The detail procedure was given in our previous communication [22]. A 1.0 wt% silicon dioxide, 1.0 wt% kaolin clay, 0.25 wt% iron ore slime, 1.0 wt% and 1.0 wt% of bentonite clay suspensions were used for flocculation studies.…”