Synthesis of Block Copolymers Based on a Macroinitiator and 2,4-Toluene Diisocyanate

The effect of the reaction medium and synthesis temperature on the polyaddition of 2,4-toluene diisocyanate to a macroinitiator representing a potassium-substituted block copolymer of propylene and ethylene oxides is revealed. Factors affecting the polyaddition accompanied by the opening of isocyanate groups via the carbonyl component are the use of catalytic amounts of acidic compounds, water in combination with trimethylamine, and maintenance of fairly low temperatures. The dielectric properties and static electrical conductivity of polymers obtained under different reaction conditions are studied. It is shown that the preferential formation of polyisocyanates of the acetal nature and, thus, block copolymers with their participation can be responsible for change in the electrophysical properties of the polymers.