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The investigations of hologram recording on a basis of photochemical polymerization reaction in polymer films have lead to creation the number of new holographic materials13. It is expected that their application will be realized in the nearest future. The performances of holographic recording useful for practice, such as sensitivity, maximum of diffraction efficiency (DE), storage, spatial resolution and other have been investigated in detail for this films4'5. But the question of mechanism of hologram formation, including the description of kinetic of photochemical and chemical stages of hologram recording is keeping open and discussed5'6. The holographic performances of HPPM-633 which consist of the light absorbing dye (Methylene Blue), initiator (triethanolamine - TEA), monomer (acrylamide -M), cross-linking monomer (hexamethylenbisacrylamide) and polymer binder (polyvinylalcohol) at He-Ne laser continuous recording were described7'8. In the preliminary investigation of hologram recording in HPPM-633 by the He-Ne laser pulses it was established that the DE about 1-5% appear at exposition time 0, 1 s with laser beam power density 0,05-0,1 W/cm2. The Fig. 1 illustrates the pulse hologram growth curves in HPPM633 , The phenomenon of hologram dark amplification (see Fig.2a,b) was observed in this experiment , That fact is in accordance with the mechanism of free-radical polymerization in HPPM. In this case the monomer polymerization in plasticizered polymer may expand independently after initial laser pulse action. It is interesting to know in which way the polymerization accrues at earlier stages. But the employment of pulse setup on the base of He-Ne laser does not allow to investigate the dark processes at time less then 0. 1 sec. To elucidate the material behaviour at the initial stages of the polymerization process immediately after excitation of the absorbing dye to the triplet state it is necessary to record the diffraction grating by laser pulse with durability about 108 sec. The DE growth of hologram under these conditions fall into nonsteady-state case of the polymerization. Thus we must to connect the hologram DE temporal dependence (DE(t)) with kinetic model of polymerization reactions in nonsteady-state case to have a possibility of the chemical interpretation of the obtained experimental date.
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