Fabrication of microstructured materials based on chitosan and D,L-lactide copolymers using laser-induced microstereolithography

The graft copolymers of chitosan and oligo(D,L-lactide) obtained by solid-phase synthesis have been used as the basis of photosensitive compositions for the fabrication of three-dimensional microstructures by laser-induced stereolithography. The electronic absorption spectra of the copolymers are close to the sum of the spectra of native chitosan and polylactide, which has been chosen as a model of grafted oligolactide chains. The fundamental absorption bands of the copolymers lie in a range to 500 nm, and their contribution to the absorption intensity of a photosensitive composition based on the copolymers at second harmonic laser frequency is insignificant. Depending on the macromolecular characteristics of the copolymers, the three-dimensional crosslinking of photosensitive compositions on their basis in the course of microstructuring occurs with different efficiency.