V. V. Tereshatov

New high-density environmentally clean polyurethane materials with binary plasticizers

Thermal and physicomechanical properties of thermoplastic polyurethane binders plasticized with mixtures of low-melting diurethanes with low-molecular-weight liquids were studied. Regular trends in the effect of components of mixed plasticizers on the properties of polyurethane thermoplastics filled with finely dispersed tungsten were revealed.

Formation of polyurethane structural materials based on mixtures of oligoethers with different reactivities

Kinetics of the reaction of urethane formation from oligopolyols with primary and secondary hydroxy groups and the influence exerted on their interaction by products formed in the reaction of N,N,N′,N′-tetrakis-(-2-hydroxypropyl)-ethylenediamine with an isocyanate were studied. Samples of high-strength polyurethane composites based on mixtures of oligoetherpolyols and the oligomeric diamine were obtained. These samples approximately twice surpass in strength materials based on oligoepoxides. The working capacity of the samples under severe climatic conditions was demonstrated.

Behavior in a humid medium of segmented polyurethane-ureas with dissimilar thermodynamically compatible and incompatible flexible blocks

Fundamental aspects of how moisture sorption affects physicomechanical properties of polyurethaneureas based on mixtures of oligoether and oligodiene diisocyanates were studied. Advantages of elastomers with dissimilar flexible blocks in providing an enhanced strength of the material in a humid atmosphere and in contact with water were revealed.

High-dense polymeric compositions based on the thermoplastic polyuretanes

The results of investigating the properties of high-dense pollution-free hybrid composites on the basis of the new type of polyurethane thermoplastics with the low-melting diurethane plasticizer are represented. The material is shown appropriate for the processing at low temperature. Strengthening of such materials is shown caused by the crystallization of the low-melting plasticizer.

New multi-block isophorone diisocyanate-based copolymers with urethane urea hard segments

Segmented polyurethane ureas (SPUUs) were synthesized on the base of oligopropylene oxide (PPO), oligotetramethylene oxide (PTMO), 2,4-toluene diisocyanate, isophorone diisocyanate (IDI), and methylene-o-chloroaniline. Structure of polymer chains with thermodynamically compatible PTMO and PPO soft segments (SS) was identified using data from rheokinetic studies of reactionary mixes with different diisocyanates. The significant swelling value in low-polar solvent toluene and non-elevated softening temperature indicates the formation of loose (defect) structure of the hard phase in compositions, synthesized using IDI. Thermal, thermomechanical, and physicomechanical properties of SPUU with variable compositions of hard segment and SS (blocks) were investigated. An interrelation between structure and properties of block copolymers of new type was estimated. Investigation results showed a significant increase in the strength of polyurethane urea at the equimolar ration between various hard blocks and SS on the base of PPO and PTMO. High strength values were obtained for SPUU in a wide diapason of stretching rates (0.56–0.003 s−1). Structural factors contributing to stability of strength properties of tetrablock-copolymers, namely: stronger inter-chain interaction in the soft phase and a “loose” structure of the hard phase. were revealed. The data relating to elevation of thermostability of these materials were given. New materials can be applied for various conditions of mechanical loading.

Stress–Strain Dependence of Cross-Linked Single-Phase Polyether Urethane

Stress–strain dependencies of cross-linked elastomers under stretching are considered. The capabilities to describe stress–strain plots of different types for elastomers, including curves with an inflection, by high-elasticity theories are examined. Limitations in the use of common high-elasticity models in the theoretical calculations of stress–strain plots are revealed. The analysis shows that the stress–strain plots with an inflection can be obtained with appropriate adjustment of the concept of finite chain extensibility. We propose a combined two-parameter model based on this concept and on the theory of high elasticity, taking into account the spatial constraints at the initial stage of stretching of the polymer network. Abilities of the new approach to describe the stress–strain dependencies in an adequate manner are demonstrated for five samples of cross-linked polyurethane over the entire range of strain under stretching.

Properties of calcium fluoride-filled cross-linked plasticized polyurethane

Thermal and physicomechanical properties of plasticized polyurethane based on oligo(butadiene)diol prepolymer and oligoethertriol were examined as influenced by microdispersed calcium fluoride. Introduction of this filler substantially improved the physicomechanical properties of the polyurethane compositions.

Influence of strong bonding with impenetrable substrate on swelling of elastomers in low-molecular-weight liquids

Swelling in various liquids was studied for a wide variety of free and bonded cross-linked polyurethane materials with different structures and densities of three-dimensional network. A calculational method was proposed for predicting the equilibrium swelling in liquids of elastic polymeric coatings bonded with a nonswelling substrate.

Structure and properties of segmented polyurethane-ureas with dissimilar soft blocks

Structure and properties of segmented polyurethane-ureas with mixed nonpolar and polar soft segments were studied. Advantages of elastomers based on mixtures of oligobutadiene and oligoether diisocyanates in providing high strength properties combined with frost resistance are demonstrated.

Polymeric materials based on oligodieneurethane-epoxy oligomers

Differential-scanning calorimetry in the dynamic mode was used to study the curing kinetics of a PDI-3AK macromolecular oligodieneurethane-epoxy oligomer with isomethyltetrahydrophthalic anhydride in the presence of a number of catalysts, modifiers, and fillers. The effect of their chemical nature on physicomechanical properties of cured polymers was examined.