The Investigation of Rheological Properties Development for Polymer Matrix Including Foaming Agent Lee, Seung Hak; Kim, Dong Gun; Lim, Sung Wook; Park, Eun Young; Park, Tae Sun; Hyun, Kyu;
Sole in the footwear usually modified with foaming agent on the polymer resin to improve the lightweightness and crush-cushion effect. In this study, we investigated rheological properties for polymer resin filled with the different type and concentration of foaming agent, capsule type foaming agent and organo-chemical foaming agent, under the time sweep test. Curing times of each polymer resin with different kind of foaming agent are delayed than reference material (epoxy resin with curing agent). In case of adding capsule type foaming agent, however, there is appropriate concentration to reduce the curing time, relatively. When foaming agent is activated, foaming force inflates the sample in contrast to condensation force of curing and then axial normal force develop to the (+) direction. Interestingly, by increase concentration of foaming agent, there is a specific point to break down the axial normal force development. The reason for this phenomenon is that coalescence of foams induce the blocking of axial normal force development.
MIF (Molded-In Foaming);capsule type foaming agent;organo-chemical foaming agent;rheological properties;time sweep test;axial normal force;
H. D. Park, "Composition for a Foamed Thermoplastic Polyurethane Sheet", patent, W.O. 2012128427 (2012).
M. Kim, H. Y. Song, D. G. Kim, H. J. Kim, G. U. Park, J. K. Yu, and K. Hyun, "The Study on the Rheological Properties of Polymer Matrix for MIF (Molded-In Foaming) Process", Elastomers and Composites, 49, 4 (2014).
K. Hyun, "Analysis and Application of Nonlinear Rheological Properties by Large Amplitude Oscillatory Shear (LAOS) Test", Polymer Science and Technology, 24, 2 (2013).
D. U. Shah and P. J. Schuble, "Evaluation of Cure Shrinkage Measurement Techniques for Thermosetting Resins", Polymer Testing, 29, 629 (2010).
K. F. Schoch, P. A. Panakel, and P. P. Frank, "Real-time Measurement of Resin Shrinkage during Cure", Thermochemica Acta, 417, 115 (2004).
F. A. Morrison, "Understanding Rheology", Oxford university press, New York, 2001.
S. M. Tosh and A.G. Marangoni, "Determination of the Maximum Gelation Temperature in Gelatin Gels", Appl. Phys. Lett., 84, 21 (2004).
H. H. Winter and F. Chambon, "Analysis of Linear Viscoelasticity of a crosslinking polymer at the gel point", J. Rheol., 30, 367 (1986).
F. Chambon and H. H. Winter, "Linear Viscoelasticity at the Gel Point of a Crosslinking PDMS with Imbalanced Stoichiometry", J. Rheol., 31, 683 (1987).