TY - JOUR

T1 - Concentration dependence of mechanical properties of polyacrylamide near the sol-gel transition point

AU - Yano, Toshimasa

AU - Kumagai, Hitoshi

AU - Fujii, Tomoyuki

AU - Inukai, Tetsuo

N1 - Funding Information:
Acknowledgments. The authors express their thanks to Professor A. Shimada, Associate Professor K. Hatae, and Dr. K. Sasaki ofOchanomizu University for their help in use of Rheolograph Sol. Part of this work was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan.

PY - 1993/1

Y1 - 1993/1

N2 - The scaling law derived from the percolation theory was applied to the concentration dependence of mechanical properties of polyacrylamide measured near the sol–gel transition point. The critical concentration of the sol–gel transition, ϕg, was estimated from the plot of concentration (ϕ) vs. the reciprocal of viscosity (η) by extrapolating 1/η to zero. The critical exponent for the sol viscosity, s, which was estimated from the slope of the log(ϕg–ϕ) vs. log η plot was about 0.7. The estimated value of s was similar to the value predicted by the percolation theory based on the superconductor–normal conductor mixture model. The critical exponent for the gel elasticity, t, as estimated from the slope of the log(ϕ–ϕg) vs. log G′ plot, where G′ was the dynamic shear modulus of the gel at a frequency of 2Hz. The value of t was about 2, which was also similar to the value predicted by the percolation theory. These results indicated the at the concentration dependences of η and G′ of polyacrylamide near the sol–gel transition point were described by the percolation theory.

AB - The scaling law derived from the percolation theory was applied to the concentration dependence of mechanical properties of polyacrylamide measured near the sol–gel transition point. The critical concentration of the sol–gel transition, ϕg, was estimated from the plot of concentration (ϕ) vs. the reciprocal of viscosity (η) by extrapolating 1/η to zero. The critical exponent for the sol viscosity, s, which was estimated from the slope of the log(ϕg–ϕ) vs. log η plot was about 0.7. The estimated value of s was similar to the value predicted by the percolation theory based on the superconductor–normal conductor mixture model. The critical exponent for the gel elasticity, t, as estimated from the slope of the log(ϕ–ϕg) vs. log G′ plot, where G′ was the dynamic shear modulus of the gel at a frequency of 2Hz. The value of t was about 2, which was also similar to the value predicted by the percolation theory. These results indicated the at the concentration dependences of η and G′ of polyacrylamide near the sol–gel transition point were described by the percolation theory.

UR - http://www.scopus.com/inward/record.url?scp=0008032052&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0008032052&partnerID=8YFLogxK

U2 - 10.1271/bbb.57.528

DO - 10.1271/bbb.57.528

M3 - Article

AN - SCOPUS:0008032052

SN - 0916-8451

VL - 57

SP - 528

EP - 531

JO - Bioscience, Biotechnology and Biochemistry

JF - Bioscience, Biotechnology and Biochemistry

IS - 4

ER -