Abstract: A polymer having structural units derived from an ester (1) of an aliphatic carboxylic acid with an aliphatic alcohol, wherein either the acid or the alcohol is ethylenically unsaturated and the other of the acid or alcohol has a medium length chain group of 440 carbon atoms; said polymer having a molecular weight of less than 30,000.

Abstract: A process for preparing a ketone of the general formula: ##STR1## in which R.sup.1 and R.sup.2 each independently represent a C.sub.1-6 alkyl or C.sub.6-12 aryl group, and R represents an alkyl, aryl, aralkyl, heterocyclic or carboxylic group, which process comprises reacting a carboxylic acid having the general formula I in which R represents a hydroxy group with a lithium compound to form the corresponding lithium salt of the carboxylic acid; reacting the lithium salt so-obtained with thionyl chloride to yield an acyl chloride having the general formula I in which R represents a chlorine atom; reacting the acyl chloride so-obtained with a secondary amine to yield an amide having general formula I in which R represents a secondary amino group; and reacting the amide so-obtained with an organometallic reagent to yield the ketone having general formula I.