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We have used Fourier transform IR spectroscopy to study the kinetics of reaction between phenylisocyanate and oligomeric polyols at room temperature. We have determined the degree of conversion and the reaction rate constants for urethane formation.Introduction. Microheterogeneous polyurethane (PU) materials with a block structure and consisting of alternating flexible and rigid blocks are not acceptable for manufacture of rigid high-strength structures. The structure of segmented polymers with a high concentration of rigid blocks is weakened by the many defects involving inclusions of the low-strength flexible phase. Broad possibilities for controlling structure formation in polyurethane composites are provided by combining oligomers of different reactivities [1]. We have proposed an approach in which the possibility of successively building up a specific structure for a polyurethane composite is determined by the use of a mixture of polyethers with primary and secondary hydroxyl groups and N,N,N ′ ,N ′ -tetrakis(2-hydroxypropyl) ethylenediamine polyol. In order to obtain a polyurethane composite structure with the fewest defects, the following reactions need to predominate: 1) reactions between an oligomeric catalytically active polyol and isocyanate, 2) addition of an oligomeric diol to an already formed active center, 3) reactions between an oligomeric polyol having secondary hydroxyl groups and isocyanate components of the polyurethane composite in the final stage of formation of the three-dimensional structure. Various methods are available for studying the kinetics of polyurethane formation (viscometry, acidimetric back titration, differential scanning calorimetry, etc.). Rather graphic information about the chemical reactions occurring during polymer synthesis is provided by the IR spectroscopy method [2].The aim of this work was to use the spectral method to study the kinetics of noncatalytic reactions between hydroxyl-containing oligomers and phenylisocyanate (PIC) at room temperature.Objects and Methods of Investigation. The kinetics of urethane formation were studied on model systems consisting of hydroxyl-containing oligomer and PIC.The objects of investigation were oligoethers: oligo(oxyethylene) diol (Laprol 402-2-100), M = 400, number of functional groups f = 2, density at temperature 25

A novel method for developing frost-resistant epoxy-urethane binders is proposed that is based on mixtures of epoxy-urethane oligomers and diglycidyl urethane formed during synthesis. The microheterogeneous elastic materials obtained by curing these mixtures by the cycloaliphatic amines have a low glass transition temperature and high mechanical properties.

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