Photooptical properties of the blend of a cholesteric copolymer and a chiral monomer

A new approach to the synthesis of cholesteric materials with a helix pitch varied under the action of light was suggested. A blend composed of a chol esteric copolymer and a chiral monomer was prepared. UV-irradiation of this blend in the presence of an initiator leads to polymerization of the monom er. The resulting homopolymer is thermodynamically incompatible with the co polymer "matrix" and forms a separate amorphous phase. This causes a decrea se in the concentration of the chiral component in the cholesteric phase an d, as a result, leads to untwisting of the helix and brings about a shift i n the maximum of the selective light reflection to the long-wave region of the spectrum. The blends under study can be employed for data recording and storage.