NOVEL CURING AGENTS FOR EPOXY RESINS Russian patent published in 2016 - IPC C08G59/44 C08G59/46 C08G59/40 C08L63/00 C08L75/00 

FIELD: chemistry.

SUBSTANCE: present invention relates to mixtures of new type containing cyanamide and at least one urea derivative, liquid curing agents for epoxy resins, as well as to epoxy resin compositions containing liquid curing agents for making fibre composites. Described is a liquid curing agent for polymer resins, particularly epoxy resins, containing: a) cyanamide and b) at least one urea derivative of formula (I) or (II), wherein residues are simultaneously or independently from each other: at least residue R¹, R², R³ is not equal to hydrogen atom, R¹, R² denote, simultaneously or independently from each other, a hydrogen atom , alkyl with 1-15 carbon atoms, cycloalkyl with 3-15 carbon atoms or a form ring from alkylene with 3-10 carbon atoms; R³ denotes a hydrogen atom, alkyl with 1-15 carbon atoms, cycloalkyl with 3-15 carbon atoms, aryl, arylalkyl, alkyl with 1-15 carbon atoms, substituted -NHC (O) NR¹R², cycloalkyl with 3-15 carbon atoms, substituted -NHC (O) NR¹R², aryl, substituted -NHC (O) NR¹R² or arylalkyl, substituted -NHC (O) NR¹R²; R⁴, R⁵, R⁶, R⁷, R⁸ denote, simultaneously or independently from each other, a hydrogen atom, halogen, alkyl with 1-15 carbon atoms, cycloalkyl with 3-15 carbon atoms, aryl, arylalkyl,-CF₃, -NHC (O) NR¹R², alkyl with 1-15 carbon atoms, substituted -NHC (O) NR¹R², aryl, substituted -NHC (O) NR¹R^2, or arylalkyl substituted -NHC (O) NR¹R², characterised by that it contains cyanamide and at least one urea derivative of formula (I) or (II) at their molar ratio of 1:1 to 4:1. Disclosed are epoxy and polyurethane resin compositions, containing: a) at least one epoxy or polyurethane resin, respectively, and b) at least one liquid curing agent described above. Disclosed is a liquid mixture as a curing for curable polymer resins, particularly epoxy resins, containing: a) cyanamide and b) at least one urea derivative of formula (I) or (II), characterised by that it contains cyanamide and at least one urea derivative of formula (I) or (II) at molar ratio of cyanamide and urea derivatives of 1:1 to 4:1. Invention also describes use of a liquid curing agent for curing compositions containing at least one epoxy resin, for curing compositions containing at least one polyurethane resin and for curing of impregnated fibrous materials or impregnated tissues, knitted or woven articles.

EFFECT: development of new types of materials, or mixtures of curing of curable resins, in particular epoxy resins that can be used in the manufacture of fibre composites and consolidate matrices, novel curing agents have sufficiently high latency in temperature range from 15 to 30°C and provide complete cross-linking of epoxy resin, are soluble in epoxy resins or completely miscible with epoxy resins and are suitable for use in infusion, injection and RTM processes.

11 cl, 7 tbl