METHOD FOR PREPARING HARDENING AGENT Russian patent published in 2006 - IPC C08G18/10 C08G18/12 C08G18/70 

FIELD: rocket technique, chemical technology.

SUBSTANCE: invention relates to a method for preparing a hardening agent for polyurethane compositions based on oligodiene rubbers. Invention describes a method for preparing a hardening agent for polyurethane compositions consisting of the following components, wt.-%: oligodiene urethane prepolymer, 80-91; 20% solution of triphenylmetane triisocyanate in dichloroethane, or 27% solution of triphenylmethane triisocyanate in ethyl acetate, 7-13, and, optionally, transformer oil, 0-10. The process is carried out in the range of temperatures 55-65°C, under residual pressure 1333 Pa for 6 h. Invention provides preparing polyurethane compositions possessing the rupture strength value at the level 38 kgf/cm^2, relative elongation 350-600%, elasticity modulus at 50°C at the level 41 kgf/cm² and adhesion strength to ballistic fuel 41 kgf/cm². Proposed compositions are able to provide working ability of articles in the range of temperature from -50°C to +50°C.

EFFECT: improved preparing method.

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