WAERMESTABILISIERTER POLYVINYLALKOHOL UND EIN VERFAHREN ZU SEINER HERSTELLUNG

摘要

The invention relates to polyvinyl alcohol (PVAL) which is prepared by alcoholysis of polyvinyl acetate (PVAC) and subsequent neutralization of the alcoholysis catalyst with an acid and to a process for producing polyvinyl acetate. In order to prepare heat-stabilized polyvinyl alcohol products, the invention proposes a polyvinyl alcohol for which the neutralization is carried out, at least in a part, using at least one organic sulphonic acid. A process for heat-stabilization of polyvinyl alcohol, in which the polyvinyl alcohol is produced by alcoholysis of PVAC using alkali alcoholate or alcoholic alkali hydroxide as the catalyst and subsequent neutralization of the alcoholysis catalyst with an acid, is carried out so that at least one sulphonic acid is added to the polyvinyl alcohol, preferably to neutralize any alkali which has not been removed by strong acids. The polyvinyl alcohol of the invention can be used, for example, to manufacture thermoplastically processible products and to manufacture polyvinyl acetals and polyvinyl formals.