The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) seeks research and development partners or licensees for novel composite hydrogels that can be used in tissue repair and other applications. Single gel networks used in tissue engineering and tissue repair applications generally become softer and more flaccid as they swell. The gels described in this technology, however, which comprise a swellable crosslinked polymer hydrogel dispersed in a crosslinked polymer matrix, mimic critical material properties of tissue extracellular matrix (ECM), for instance, becoming stiffer and tougher upon swelling.