New polyisocyanurate catalysts which exhibit high activity at low temperature

摘要

In polyisocyanurate foam production,alkali metal catalysts of organic carboxylic acid and hydroxyalkyltrimethyl quaternary ammonium salts are traditional standards as polyisocyanurate foam catalysts.The activity of these catalysts,however,is not efficient at low temperature,therefore,the initiation reactions are extremely delayed and the flowability of the foam system is far to inferior.In addition,the foam exhibited shrinkage when the thickness of the sprayed layer was thin and the temperature was low while applying the sprayed foams.The combination of other tertiary amine catalysts could improve the flowability,however,the flammability of the foam would be a hazard because the isocyanurate reaction has not fully progressed.