oligomeric alkylenebisphenyl phenylphosphonites , easily prepared by the reaction of phenyldichlorophosphine and certain bis - phenols in the presence of a base , provide enhanced stabilizing activity to hydroxyalkyleneyl isocyanurates when combined to stabilize organic materials subject to degradation . these oligomeric phenylphosphonites are not expensive , resist hydrolysis , do not evaporate from or are leached out of polymers when mixed therewith and provide excellent protection to polymers during processing and result in decreased water carry over of polymer films on leaving a cooling water bath during the film forming process .