2013 Volume 41 Issue 4 Pages 223-227
We have been focusing on the normal force difference in the high shear rate region as moisture feel for lipsticks. It is widely known that the use of polymeric materials is effective to increase the normal force. However the control of spinnability has been a problem for ordinary polymers like polyether. A cellulose derivative with low spinnability has been developed. Spinnability and viscoelasticity were evaluated for a polyether (POE) and a long-alkyl acylated cellulose derivative (RCE). Although spinnability was easily evaluated by using the tack mode of rheometer, it was difficult to measure 10 cm or more. Since dynamic moduli of both samples could not be expressed with a single Maxwell mode, one of these samples is shifted by the correspondence of their tan δ. The storage modulus, G', of RCE with low spinnability is greater than that of POE with high spinnability. For the non-linear rheology, we found that the correspondence between the first normal stress coefficient, Ψ1, and G'/ω2 is different between two samples. POE with high spinnability has no correspondence of this relationship.