A Comparison of the Viscoelastic Properties of Starch-polyacrylamide Graft Copolymers Produced in Dimethyl Sulfoxide and Water
Received Date: Jul 21, 2016 / Accepted Date: Aug 14, 2017 / Published Date: Aug 21, 2017
The rheological properties of starch-polyacrylamide graft copolymers prepared in water and in dimethyl sulfoxide (DMSO) were investigated and compared. Both materials can absorb huge amount of water and form gels. Both water-made and DMSO-made starch-polyacrylamide graft copolymer gels exhibited viscoelastic solid properties. The analysis of modulus, concentration dependence, and stress relaxation measurements indicated that both water- made and DMSO-made starch-polyacrylamide gels were physical gels meaning that the cross-linkers between the molecules were of physical junctions. The linear range rheological property analysis suggested that water-made starch-polyacrylamide graft copolymers should be ‘weak’ gels at lower concentrations (<7%), but be ‘strong’ gels at higher concentrations (≥ 9%) however, the DMSO-made starch-polyacrylamide graft copolymers should be ‘weak’ gels at all measured concentrations. The non-linear steady shearing rheological properties studies showed that both water- made and DMSO-made starch-polyacrylamide graft copolymer gels exhibited shear thinning behaviour, which can be well fitted with the power law constitutive equation. The function and behaviour of both water-made and DMSO-made starch-polyacrylamide graft copolymer gels imply that these starch-based biomaterials can be potential candidates for applications in cosmetic and wound skin care gels; and the desired material’s behaviour and property can be manipulated by the copolymer’s concentration and preparation method such as in water or in DMSO.
Keywords: Biodegradable material; Graft copolymer; Polyacrylamide; Rheology; Starch; Viscoelastic properties
Citation: Xu J, Selling GW (2017) A Comparison of the Viscoelastic Properties of Starch-polyacrylamide Graft Copolymers Produced in Dimethyl Sulfoxide and Water. Rheol: open access 1: 109.
Copyright: © 2017 Xu J, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.