Process for the preparation of polymeric acetal carboxylates

Abstract

The alkali metal, ammonium and alkanol ammonium salts of polymeric acetal carboxylates are stable detergent builders under laundry use conditions but depolymerize at lower pH, making the polymer fragments more readily biodegradable in waste streams. Such polymeric acetal carboxylates can now be made by an improved process which includes the steps of bringing together in a reaction zone under polymerization conditions an ester of glyoxylic acid and a polymerization initiator, and adding an alkyl vinyl ether to the resulting polymer in the presence of a solvent having a dielectric constant of at least 15, such as an alkyl nitrile and a haloacetic acid catalyst, such as trifluoroacetic acid, to stabilize the polymer against rapid depolymerization in alkaline solution. The preferred solvent is acetonitrile.

Dependencies are inferred from the claim text.