Process for the stabilization of polyvinyl chloride and stabilizer compositions

A stabilizer composition of polyvinyl chloride molding mixtures which comprises

• (a) from about 4 to 100 parts by weight of a synthetic, crystalline sodium zeolite A of small particle size and containing from about 13 to 25 percent by weight of water of crystallization, which has the composition
• 0.7-1.1 Na.sub.2 O.Al.sub.2 O.sub.3.1.3-2.4 SiO.sub.2
• with respect to the anhydrous form;
• (b) from about 1 to 30 parts by weight of one or more calcium salts of fatty acids with from 8 to 22 carbon atoms;
• (c) from about 1 to 10 parts by weight of one or more zinc salts of fatty acids with from 8 to 22 carbon atoms;
• (d) from about 4 to 40 parts by weight of partial esters of polyols with from 2 to 6 carbon atoms and from 2 to 6 hydroxyl groups and fatty acids with from 8 to 22 carbon atoms, which contain an average of at least one free polyol-hydroxyl group per molecule and have an OH-number of from about 140 to 580;
• and
• (e) from about 2 to 20 parts by weight of thioglycolic acid esters of polyols with from 2 to 6 hydroxyl groups and/or thioglycolic acid esters of monofunctional alcohols with from 8 to 22 carbon atoms.

In a process for stabilizing polyvinyl chloride molding mixtures which comprises admixing a stabilizing amount of stabilizer with 100 parts by weight of polyvinyl chloride or copolymer of vinyl chloride

• the improvement consisting of using
• (a) from about 0.2 to 5 parts by weight of a synthetic, crystalline sodium zeolite A of small particle size and containing from about 13 to 25 percent by weight of water of crystallization, which has the composition
• 0.7-1.1 Na.sub.2 O.Al.sub.2 O.sub.3.1.3-2.4 SiO.sub.2
• with respect to the anhydrous form;
• (b) from about 0.05 to 1.5 parts by weight of one or more calcium salts of fatty acids with from 8 to 22 carbon atoms;
• (c) from about 0.2 to 2.0 parts by weight of partial esters of polyols with from 2 to 6 carbon atoms and from 2 to 6 hydroxyl groups and fatty acids with from 8 to 22 carbon atoms, which contain an average of at least one free polyol-hydroxyl group per molecule and have an OH-number of from about 140 to 580;
• and
• (e) from about 0.1 to 10 parts by weight of polyols with from 2 to 6 hydroxyl groups and/or thioglycolic acid esters of such polyols and/or thioglycolis acid esters of monofunctional alcohols with from 8 to 22 carbon atoms
• for said stabilizer.