A series of poly(styrene-acrylonitrile)/poly(ethyl acrylate-n-butyl acrylate) latex interpenetrating polymer networks (LIPNs) are synthesized by changing the kind of crosslinker and introducing a buffer. The results show that the crosslinker has an important effect on the damping properties of the LIPNs; divinylbenzene is the best crosslinker in the study. Moreover, introducing a buffer into LIPNs leads to an increase of the damping values over the temperature range where the damping value surpasses 0.5. The LIPN blend prepared by mixing LIPNs results in broadening of the damping peak, therefore improving the damping properties. Tests of the damping properties show that the LIPNs have good practical value.