the alkali metal , ammonium and alkanol ammonium salts of polymeric acetal carboxylates are stable detergent builders under laundry use conditions but depolymerize in mildly acidic media , making the polymer fragments more readily biodegradable in waste streams . such polymeric acetal carboxylates can now be made by a process which comprises bringing together in a reaction zone under polymerization conditions an ester of glyoxylic acid and a polymerization initiator , and adding to the resulting polymer an alkyl vinyl ether and an organoaluminum compound to stabilize the resulting polymer against rapid depolymerization in alkaline solution . the preferred alkyl vinyl ether is ethyl vinyl ether , and the preferred organoaluminum compounds are alkyl aluminum halides and trialkyl aluminum .