Rapid prototyping by means of stereolithography using different types of photopolymers has gained increasing interest because cellular structures can be built at a high resolution with sub-lm feature sizes. Structures made with digital light processing and microstereolithography and rapid prototyping based on two-photon absorption photopolymerization techniques are presented. Soluble photopolymers were developed to substitute crosslinked photopolymers as mold materials and to extend the variety of materials which can be cast. With these molds, the processing of 'bio-inspired' ceramic composites with a controlled architecture from a macroscopic scale down to the nanometer range is possible. Another example is the development of biophotopolymers that are based on commercially available reactive diluents and modified gelatin for the fabrication of cellular bone replacement materials. Biocompatibility was investigated by seeding with osteoblast-like cells.

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Intrigued by the good performance of 1,5‐diphenylpenta‐1,4‐diyn‐3‐one (DPD) as photoinitiator for radical polymerization we prepared and investigated several donor substituted derivatives. UV‐Vis spectroscopy revealed a gradual red‐shift of λmax and higher extinction in the order of the donor capability. A methoxy‐substituted derivative (O‐DPD) exhibited significant photoinitiation activity in photo‐DSC experiments. Steady state photolysis experiments showed decreased decomposition rates with increasing donor capability. A dimethylamino derivative N‐DPD was even photostable under these conditions. Because of to the D‐π‐A‐π‐D system of these compounds two‐photon induced 3D photopolymerization experiments were performed and N‐DPD showed outstanding performance compared to often applied single photon initiators. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3280–3291, 2007

Roll-to-roll UV nanoimprint lithography has superior advantages for high-throughput manufacturing of micro- or nano-structures on flexible polymer foils with various geometries and configurations.