| abstract |
A branched chain polyalkylene polyamine ("PAPA") amine having a plurality of amine groups, including a secondary amine group between terminal primary amine groups, and having at least two carbon atoms between each amine group, is alkylated by reduction with a ketone to obtain a PAPA alkylated only at the level of an unimpeded primary amine group. A preselected degree of steric hindrance of the amino groups close to each end of the chain makes cyclization possible by "ketoform synthesis" by reaction with a ketone so as to form a ring of polysubstituted piperazinone ("PSP") which comprises N atoms close primary and secondary amine groups belonging to the alkylated PAPA. The PSP thus formed can then react with a reactive triazine ring so that a PSP substituent is linked to the triazine ring by a single N atom and at least two C atoms, thus forming a 2-oxo-piperazynil- triazine ("PIP-T"). PIP-T oligomers can be prepared. PIP-T compounds are excellent stabilizers against degradation caused by ultraviolet (UV) light in synthetic, light-sensitive resinous materials. |