Process Control of Loss Factor in Soft Materials
Loss tangent defined by the ratio of loss modulus to storage modulus, G”/G’, is widely used as a measure of energy loss for rubber materials. We can expect high loss tangent due to unstable state of polymer chains in large deformation. However, chemical cross-linking is usually introduced in no deformation where we cannot expect high loss tangent. Even if introduced in deformed state, polymer chains take relaxation before completion of cross-linking. In this study, hence, a novel two-step cure has been proposed. The loss tangent by two-step cure has been found to be higher than that by one-step cure in no deformation, showing effectiveness of the process proposed.
Masayuki Nogami, Riguang Jin, Toshihiro Kasuga and Wantai Yang
J. H. Wu et al., "Process Control of Loss Factor in Soft Materials", Advanced Materials Research, Vols. 11-12, pp. 725-728, 2006