M. A. Makarova

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.

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.

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.

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.

Polyurethane adhesive composition cured at room temperature

The influence of polyfunctional hydroxyl-containing oligomer on the rheological, physicomechanical, and adhesive properties of polyurethane composite based on multicomponent oligomer blend and polyisocyanate is investigated. The kinetics of curing is investigated by the viscometric method, and the composition lifetime is determined. It is shown that the polyurethanes under investigation can be used as fast-curing adhesive composites of cold curing operating in a temperature interval of up to +90°C.

Heterogeneous polymer materials based on oligodienetetraurethanediepoxide and oligoetherdiisocyanate

Based on mixtures of oligodienetetraurethanediepoxide and oligoetherdiisocyanate with low thermodynamic compatibility of the components, microheterogeneous elastomers are obtained and their properties are studied. The advantages of the new materials in strength and adhesion to steel over cross-linked elastomers based on individual oligovinylisoprenetetraurethanediepoxide are shown.

Characteristics of polyether urethanes with mixed soft segments, prepared by two- and three-step procedures

A three-step procedure for preparing polyurethanes with mixed polyether segments was suggested. It involves preparation of the “inverse” prepolymer by the reaction of one of oligodiisocyanates with 1,4-butanediol taken in a double excess, followed by the reaction with the other oligodiisocyanate. Polyurethanes with alternating poly(tetramethylene oxide) and poly(propylene oxide) soft segments were prepared by this procedure. Such materials surpass polyurethanes prepared from a mixture of oligodiisocyanates in the strength and softening point of the hard phase. In contrast to poly(tetramethylene oxide) urethane, elastomers with mixed polyether segments do not crystallize.

Elastic and moisture-resistant compounds based on mixtures of oligotetraurethane diepoxide, epoxy-diane resin, and aromatic diamine

Elastic and cold-resistant compounds based on oligodiene tetraurethane diepoxide and ED-20 epoxy-diane resin were obtained. The structure of compounds formed upon curing of the reaction mixture with aromatic diamine was studied. The advantages of new compounds in terms of physicomechanical and adhesion properties compared to a compound containing no ED-20 resin are demonstrated.