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Using birefringent polymeric materials characterized by regulated acoustic stiffness for dynamic photoelasticity

There is a great necessity for birefringent polymers characterized by regulated acoustic stiffness in solving wave process problems in continuous media by means of dynamic photoelasticity. This type of polymer is particularly significant for the investigation based on models of stress waves in composite constructions consisting of various materials. Special types of polymers are generally used as basic materials for creating models used in dynamic investigations. These are hard polymers based on epoxy oligomers cured by organic acid anhydrides. The speed of longitudinal wave spreading is 1,900 - 2,000 m.p.s. in such anhydrides. In the present survey, we consider the synthesis of birefringent polymers in accordance with two following directions: (1) synthesis of interpenetrating nets (IPN) through simultaneous curing of epoxymethyltetrahydrophthalic compound and bis(allylcarbonate) polypropylenglycol (BACPG); (2) polycyclotrimerization of carbofunctional silicon-organic macrodiisocyanates. The latter material -- carbofunctional silicon-organic macrodiisocyanates -- is synthesized by the interaction of oligomeric silicon-organic diols (Mn equals 282 - 3,500) with a double molar surplus of 2.4- tolylenediisocyanate. In both cases, the curing process is controlled with the help of the IR-spectroscopy method and through the gel-fraction accretion.