A biodegradable polyethyleneoxide polycaprolactone polyethyleneoxide (PEO-PCL-PEO-or PECE) triblock polymer was synthesized as a structure-directing agent for high-surface area silica formation. Systematic end-group functionalization of the triblock polymer, prior to its use as a structure-directing agent for high-surface area silica growth, imparts an additional reactive function that is exploited to grow a continuous organic phase within and around the silica particles. Hence, the biodegradable triblock also acts as a macromer whose dual function leads to in-situ generation of intimately mixed biopolymer/nanoporous-silica composite networks. This composite can be both biodegradable and biocompatible, and the modulus is comparable to other non-biodegradable materials. (C) 2014 Elsevier Ltd. All rights reserved.