Method for evaluating rheological properties of a gel

A method for evaluating the rheological properties of at least one gel, comprising determining the extent of the plastic domain in stress ζc−ζp and in strain γc−γp, the determining being carried out according to the steps of:

• subjecting at least one sample of at least one gel to oscillatory mechanical stresses at a fixed frequency,
• determining and plotting the curves of the elastic modulus G′ and of the viscous modulus G″ as a function of the strain and of the stress,
• determining ζc and γc at the point of intersection Xc of the curves of G′ and G″ under stress and strain,
• determining ζp and γp by fixing a value of G′ (G′p), as the value for which the elastic modulus G′ has decreased from 5 to 15% relative to the value of G′ at the plateau of the linear domain, and that is defined as the entry value into the plastic domain, and
• calculating ζc−ζp and γc−γp.