Synthesis of polyurethane compounds

These domains are connected by hydrogen bonds, which act as knots or crosslinking centers to create flexible blocks.13 Microphase separation and the appearance of domain structure are considered to be the main factors, which determine the unique properties of this class of polymers. 

Mono- and two-stage methods are used to produce articles from polyurethane-containing materials. 4 In the two-stage method, prepolymers, e.g.macro(diisocyanates), are synthesized by the reaction of polyesters containing end-hydroxy groups (polyols) with diisocyanates  

Low-molecular-weight glycols or diamines are used for further propagation of prepolymer molecules and for crosslinking the chains  

The reagent ratio in the reactive mixture is selected so that there is a small surplus of isocyanate groups. 

Property PU-I pu-n Hydrocarbonate oligomer Thiokol Silicone organic oligomer 

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