Styrene-ethylene/butylene-styrene blends for improved constrained-layer damping

The influence on the adhesion to some metal surfaces and the damping proper ties of various modified styrene-ethylene/butylene-styrene (SEBS) materials was evaluated. Modification of the different phases of the SEBS with resin s was shown to have a large effect on the damping properties of the polymer s, which were evaluated by dynamic mechanical analysis (DMA). A small amoun t of maleic anhydride grafted onto the EB block was found to lead to a sign ificant improvement in the adhesion of the polymer to some metal surfaces w ithout affecting the damping properties of the polymers. The results of the DMA tests on the polymers were used to calculate the composite loss factor (CLF) for a steel laminate, which consisted of two steel plates with a pol ymeric layer in between, according to the theory proposed by Ross, Ungar, a nd Kerwin. The calculated results were compared with the measured CLFs dete rmined in vibrating beam tests (VBTs). The agreement between the calculated and measured values was quite fair, provided that the DMA values used for the calculations were recalculated to the actual higher frequencies used in the VBTs, using the time-temperature superposition principle. (C) 2001 Joh n Wiley & Sons, Inc.