COMPOSITE STRUCTURAL COMPOSITE ELEMENTS STRENGTHENED BY FIBRES AND THEIR MANUFACTURING Russian patent published in 2017 - IPC C08G18/40 C08G18/58 C08J5/24 

FIELD: chemistry.

SUBSTANCE: elements comprise one or more fibrous layers impregnated with polyurethane and polyisocyanurate, which are prepared from a reaction mixture consisting of one or more polyisocyanates (A), one or more polyether polyols (B), one or more polyepoxides (C), one or more hidden catalysts (D), if necessary additives (E) and, if necessary, a fibrous material (F). The viscosity of the reaction mixture is from 20 to 500 mPas⋅ at 25 °C. The ratio of the number of NCO group of component (A) and the number of OH groups of component (B) is from 10:1 to 16:1. The ratio of NCO groups of component (A) and the number of epoxy groups of component (C) is from 2:1 to 25:1. The molar ratio of the number of epoxy groups of component (C) and the number of moles of the latent catalyst of component (D) is from 1.1:1 to 12:1. The method for manufacturing the fibrous composite structural elements comprises forming a mixture of the above components (A) to (F), loading the fibrous material into a half mould, introducing the mixture produced into this mould, the loaded fibrous material being impregnated, curing the mixture at a temperature of 50 to 170 °C.

EFFECT: elements are dense, optically transparent and have a good resistance to heat.

2 cl, 1 tbl, 2 ex