Rheological properties of glutaraldehyde-crosslinked collagen solutions analyzed quantitatively using mechanical models

• Published in: Materials Science & Engineering C 2016-06, Vol.63, p.10-17
• Main Authors: Tian, Zhenhua, Duan, Lian, Wu, Lei, Shen, Lirui, Li, Guoying
• Format: Article
• Language: English
• Subjects: Animals; Cattle; Collagen; Collagen - chemistry; Collagens; Crosslinking; Dynamical systems; Dynamics; Elasticity; Glutaraldehyde; Mathematical models; Mechanical models; Models, Theoretical; Pseudoplasticity; Rheological properties; Rheology; Shear Strength; Solutions - chemistry; Transition Temperature; Viscosity; Yield stress
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2016.02.047

Understanding the rheological behavior of collagen solutions crosslinked by various amounts of glutaraldehyde (GTA) [GTA/collagen (w/w)=0–0.1] is fundamental either to design optimized products or to ensure stable flow. Under steady shear, all the samples exhibited pseudoplasticity with shear-thinning behavior, and the flow curves were well described by Ostwald-de Waele model and Carreau model. With increased amounts of GTA, the viscosity increased from 6.15 to 168.54Pa·s at 0.1s−1, and the pseudoplasticity strengthened (the flow index decreased from 0.549 to 0.117). Additionally, hysteresis loops were evaluated to analyze the thixotropy of the native and crosslinked collagen solutions, and indicated that stronger thixotropic behavior was associated with higher amount of GTA. Furthermore, the values of apparent yield stress were negative, and a flow index