Dersleri yüzünden oldukça stresli bir ruh haline sikiş hikayeleri bürünüp özel matematik dersinden önce rahatlayabilmek için amatör pornolar kendisini yatak odasına kapatan genç adam telefonundan porno resimleri açtığı porno filmini keyifle seyir ederek yatağını mobil porno okşar ruh dinlendirici olduğunu iddia ettikleri özel sex resim bir masaj salonunda çalışan genç masör hem sağlık hem de huzur sikiş için gelip masaj yaptıracak olan kadını gördüğünde porn nutku tutulur tüm gün boyu seksi lezbiyenleri sikiş dikizleyerek onları en savunmasız anlarında fotoğraflayan azılı erkek lavaboya geçerek fotoğraflara bakıp koca yarağını keyifle okşamaya başlar

GET THE APP

A Comparison of the Viscoelastic Properties of Starch-polyacrylamide Graft Copolymers Produced in Dimethyl Sulfoxide and Water | OMICS International| Abstract

Rheology: Open Access
Open Access

Our Group organises 3000+ Global Conferenceseries Events every year across USA, Europe & Asia with support from 1000 more scientific Societies and Publishes 700+ Open Access Journals which contains over 50000 eminent personalities, reputed scientists as editorial board members.

Open Access Journals gaining more Readers and Citations
700 Journals and 15,000,000 Readers Each Journal is getting 25,000+ Readers

This Readership is 10 times more when compared to other Subscription Journals (Source: Google Analytics)
  • Research Article   
  • Rheol: open access 2017, Vol 1(2): 109

A Comparison of the Viscoelastic Properties of Starch-polyacrylamide Graft Copolymers Produced in Dimethyl Sulfoxide and Water

Jingyuan Xu* and Gordon W Selling
US Department of Agriculture, National Centre for Agricultural Utilization Research, Agricultural Research, , USA
*Corresponding Author : Jingyuan Xu, US Department of Agriculture, National Centre for Agricultural and Utilization Research, Agricultural Research Service, USA, Tel: 309-681-6359, Fax: 309-681-6691, Email: james.xu@ars.usda.gov

Received Date: Jul 21, 2016 / Accepted Date: Aug 14, 2017 / Published Date: Aug 21, 2017

Abstract

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.

Top