Effect of a functional polymer on the rheology and microstructure of sodium alginate

Lei Du; Amin GhavamiNejad; Zhi-Chao Yan; Chandra Sekhar Biswas; Florian J Stadler

doi:10.1016/j.carbpol.2018.07.001

Effect of a functional polymer on the rheology and microstructure of sodium alginate

Carbohydr Polym. 2018 Nov 1:199:58-67. doi: 10.1016/j.carbpol.2018.07.001. Epub 2018 Jul 3.

Authors

Lei Du¹, Amin GhavamiNejad², Zhi-Chao Yan³, Chandra Sekhar Biswas¹, Florian J Stadler⁴

Affiliations

¹ College of Materials Science and Engineering, Shenzhen Key Laboratory of Polymer Science and Technology, Guangdong Research Center for Interfacial Engineering of Functional Materials, Shenzhen University, Shenzhen 518060, PR China; Key Laboratory of Optoelectronic Devices and System of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 516080, PR China.
² Advanced Pharmaceutics & Drug Delivery Laboratory, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario, M5S 3M2, Canada.
³ College of Materials Science and Engineering, Shenzhen Key Laboratory of Polymer Science and Technology, Guangdong Research Center for Interfacial Engineering of Functional Materials, Shenzhen University, Shenzhen 518060, PR China.
⁴ College of Materials Science and Engineering, Shenzhen Key Laboratory of Polymer Science and Technology, Guangdong Research Center for Interfacial Engineering of Functional Materials, Shenzhen University, Shenzhen 518060, PR China. Electronic address: [email protected].

PMID: 30143165
DOI: 10.1016/j.carbpol.2018.07.001

Abstract

Here, we report on the effect of functional copolymer poly(N-isopropylacrylamide-co-4-vinyl-phenylboronic acid) (NIBA) on the rheology and network structure formed by sodium alginate (SA) through linear and nonlinear viscoelasticity measurements. The hydrogel moduli at pH 3 increased with increasing NIBA addition, while the yield point decreased. Furthermore, these hydrogels showed strain-softening behavior, weak G″-overshoot marking the onset of nonlinearity, and good self-healing properties after large deformation. The zero-strain nonlinearity parameter (Q₀) was found to be more sensitive to NIBA-addition than the linear viscoelastic properties. The blends showed a clear peak in the startup test except for SA alone and the peak intensity increased with increasing NIBA-concentration. Finally, based on all data, gelation mechanism and interaction of SA and NIBA will be clarified.

Keywords: Fourier-transform-rheology; Functional polymer; Large-amplitude oscillatory shear; Self-healing; Sodium alginate.