METHOD OF INCREASING RELATIVE DENSITY OF POLYAMIDE Russian patent published in 1997 - IPC

FIELD: chemistry of polymers. SUBSTANCE: claimed process comprises heating polyamide in the presence of base and catalyst. The catalyst comprises compound of formula: wherein X is 2-pyridyl; 2-pyridyl substituted in positions 3,4 and/or 5 by at least one group C_xH_2x+1 wherein X is form 0 to 10; 4-morpholino; 1-pyrrolidino, 1-piperidino or wherein R′ is the same or different and is alkyl group containing from 1 to 12 carbon atoms, and n is 2-5; R is the same or different and represents hydrogen atom or alkyl group containing from 1 to 12 carbon atoms, one or more hydrogen atoms of alkyl group is substituted by C_xH_2x+1 wherein X is from 1 to 10, and/or by unsubstituted phenyl group, and/or by phenyl group containing Cl, Br, C_xH_2x+1 or O-C_xH_2x+1 wherein X is 1 to 10; R″ is the same or different and is hydrogen atom or C_xH_2x+1 wherein X is from 1 to 10. EFFECT: higher efficiency. 14 cl, 5 tbl