ALDITOLDIACETALE VON GROSSER REINHEIT UND FREI VON ORGANISCHEN LOESUNGSMITTELSPUREN SOWIE VERFAHREN ZU IHRER HERSTELLUNG

Diacetals resulting from the dehydrocondensation of an alditol containing 5 or 6 carbon atoms and of a benzaldehyde such as especially DBS, BEBS, BMBS or DBX, which are at least 95 % pure and free from traces of organic solvents, and a process for preparing them in an aqueous medium in the presence of an acidic catalyst, according to which the acetalisation is carried out by mixing the reactants by stirring, the reaction mixture is then neutralised with a base, and the solid phase is then separated from the liquid phase and washed with hot water, according to which: the initial molar ratio of the benzaldehyde to the alditol is lower that 2/1, the acidic catalyst is an arylsulphonic acid, the initial molar ratio of the arylsulphonic acid to the benzaldehyde is higher than 0.6 and the reaction temperature is lower than approximately 45 DEG C. Application especially to the clarification and stabilisation of polyolefins.