| abstract |
A process for stabilizing a halogen-containing plastic against thermal or photochemical degradation by adding to the plastic an additive consisting essentially of cationic layer compounds corresponding to general formula (I):where M(II) represents at least one divalent metal ion and An- represents an acid anion having the charge n-(n=1, 2 or 3) and 1<x<5, y>z, (y+nz)=2x+3 and 0<m<10, and wherein the cationic layer compounds have been prepared by adding alkali metal hydroxide to a water-containing mixture of at least one source of divalent metal ions M(II), one source of the anion An- and crystalline aluminum hydroxide in a quantity of 1 to 20 mole-%, based on aluminum hydroxide, heating the mixture for 10 to 240 minutes at a temperature of 100° C. to 240° C., and drying the mixture to form a powder without previous separation of the solid from the aqueous phase. |