Biodegradable plastics and hydrogels possess distinct mechanical/biocompatibility properties that are indispensible in device design. It is desirable to combine their advantages by creating hybrid materials/structures. Here, a new/method based on a reversible addition fragmentation chailn transfer (RAFT) reaction was demonstrated by direct polymerization of polyethylene glycol (PEG) hydrogel network on polycaprolactone (PCL) electrospun fibers. The resulting hybrid fibrous matrices exhibited unique material characteristics including high-speed water absorption without visible matrix deformation and plastic bulk properties with low surface elasticity that were otherwise nonachievable in plastics or hydrogels alone. The mechanically strong, water-absorbing fibrous composite materials can potentially find important applications in biomedical devices.