Abstract: Hydroxyethyl methacrylate (HEMA) as post-crosslinker, semi-IPN polymethacrylate sandwich composite oil-absorptive materials were attained via suspension polymerization, its structure and thermal properties were analyzed by using Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), dynamic mechanical thermal analyzer (DMA), while its oil-absorptive properties, including oil absorbency, oil retention ratio, gel fraction, the polymer-solvent interaction parameter, were tested and analyzed. These data and analysis indicated that there was physical cross-linking structure in the feeds. As the proportion of HEMA increasing, more perfect crosslinking structure was formed. There was an excellent oil-absorptive performance when the content of HEMA was appropriate, oil absorbency, to toluene, trichloroethylene were respectively up to about 750% and 800%.