| 摘要 |
Polymers or oligometic compounds of the general formula <IMAGE> in which X, Xa and Xb are an ester, amide or cyano group, Y, Ya and Yb are -O- or -NR10-, R1, R1a and R1b are a group which contains a polyalkylpiperidine radical, and R1a can also be alkyl, and R3, R3a and R3b are alkylene, alkenylene, arylene-dialkylene, cycloalkylene-dialkylene or monooxa-alkylene or polyoxa-alkylene, can be prepared by the polycondensation of malonic acid esters or amides or cyanoacetic acid esters or amides with difunctional compounds, preferably dihalogen compounds, in the presence of bases. The products obtained have a molecular weight of 800 to 20,000 and are outstanding light stabilizers for organic polymers.
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