Large amplitude oscillatory shear rheology for nonlinear viscoelasticity in hectorite suspensions containing poly(ethylene glycol)》.pdfVIP

Polymer 52 (2011) 1402e1409 Contents lists available at ScienceDirect Polymer journal homepage: www.else /locate/polymer Large amplitude oscillatory shear rheology for nonlinear viscoelasticity in hectorite suspensions containing poly(ethylene glycol) Weixiang Sun, Yanrui Yang, Tao Wang, Xinxing Liu, Chaoyang Wang, Zhen Tong* Research Institute of Materials Science, South China University of Technology, Guangzhou 510640, China a r t i c l e i n f o a b s t r a c t Article history: The effect of poly(ethylene glycol) (PEG) on the nonlinear viscoelasticity of Laponite suspensions con- Received 4 November 2010 taining NaCl was investigated with large amplitude oscillatory shear rheology. The molecular weight Received in revised form (Mw ) of PEG was 4k, 10k and 35k, and the concentration of PEG was varied from 0.063 wt% to 2.4 wt%. 7 January 2011 The dynamic strain sweep showed that the nonlinearity appeared at g0 30% with a stress overshoot at Accepted 22 January 2011 Available online 1 February 2011 g0 ¼ 50e70%. The intensity ratio I3/1 from Fourier-transform increased with g0 when entering the nonlinear regime and leveled off at g0 100% with higher slope and constant value for the PEG of higher Mw or lower concentration. I3/1 revealed the structure difference in the suspensions induced by Keywords: Large amplitude oscillatory