MIXTURE OF POLYAMIDES WITH IMPROVED FLOWABILITY Russian patent published in 2019 - IPC C08L77/06 C08J5/04 C08J5/24 B29C70/46 

FIELD: chemistry.

SUBSTANCE: invention relates to a thermoplastic composition with improved flowability in a molten state based on polyamides, preferably suitable for producing composite materials obtained by impregnating a reinforcing filler, a method of producing a composite article and use of an invariable polyamide as an additive which lowers viscosity. Thermoplastic composition contains at least: (a) a polyamide having a molten viscosity greater than or equal to 50 Pa·s, and non-variable polyamide (b) having a molten viscosity which is lower than the viscosity of polyamide (a) in molten state and greater than 0.8 Pa·s. Polyamide (b) has number average molecular weight Mn, which is lower than that of polyamide (a). Said composition has a melt viscosity, stabilized at a value lower than the value of viscosity of polyamide (a) in molten state. In polyamide (b) concentration of terminal amino groups (AEG) and/or terminal carboxy groups (CEG) is less than or equal to 20 meq/kg or concentration of end amino groups (AEG) is greater than or equal to 25 meq/kg, concentration of end acid groups (CEG) is greater than or equal to 25 meq/kg, and concentration of terminal blocking groups (BEG) is greater than or equal to 25 meq/kg.

EFFECT: invention provides better impregnation of fibrous reinforcing fillers (increased content of fibres, shorter duration of process cycle) while maintaining good mechanical characteristics.

18 cl, 5 tbl, 6 ex