Patent Number: 8,575,401

Title: Method for purifying crude polymethylols

Abstract: The present invention relates to a process for purifying crude polymethylol which comprises polymethylol of the formula (I) (HOCH.sub.2).sub.2--C--R.sub.2 (I) in which each R is independently a further methylol group or an alkyl group having 1 to 22 carbon atoms or an aryl or aralkyl group having 6 to 22 carbon atoms, and also hydroxy acid of the formula (IV) ##STR00001## in which each R is independently as defined above, which comprises performing the purification in a distillation column, the bottom of the distillation column being connected to an evaporator with a short residence time. The present invention further relates to a composition comprising polymethylol and 1 to 10 000 ppm by weight of an ester of polymethylol and of a hydroxy acid and to the use thereof.

Inventors: Sirch; Tilman (Schifferstadt, DE), Steiniger; Michael (Neustadt, DE), Maas; Steffen (Bubenheim, DE), Rittinger; Stefan (Mannheim, DE)

Assignee: BASF SE

International Classification: C07C 29/80 (20060101)

Expiration Date: 1/05/12017