화학공학소재연구정보센터
Journal of Polymer Science Part B: Polymer Physics, Vol.54, No.17, 1693-1701, 2016
The Impact of Damage Accumulation on the Kinetics of Network Strength Recovery for a Physical Polymer Gel Subjected to Shear Deformation
Shear rheophysical experiments were used to quantify the kinetics of strength recovery of model thermoreversible polymer gels that were fractured and ultimately sheared to different total magnitudes of strain (700 and 4000%) before resting for set periods of time. Relationships between the amount of strength recovered and the normalized ratio of resting times to characteristic relaxation times were developed. It was found that gels displayed fully healed networks within timescales that were 2-3 orders of magnitude greater than the gel's characteristic relaxation time. Gels deformed to 700% applied strain either healed slower at lower gel concentrations as compared to experiments at larger applied strains due to possible viscous heating, or healed faster from incomplete fracture propagation for higher gel concentrations. (C) 2016 Wiley Periodicals, Inc.