UNSATURATED POLYESTER RESINS OR VINYL ESTER RESIN COMPOSITIONS

摘要

The present invention relates to a method of providing unsaturated polyester resin or vinyl ester resin compositions containing a phenolic inhibitor, wherein first a primary resin composition containing a phenolic inhibitor is produced with the phenolic inhibitor being selected from the group of phenolic compounds of which the O-H bond dissociation enthalpy is in the range of from 78 to 91 kcal/mol, and wherein in a further step subsequently both an N-oxyl radical compound and an amine compound is added to said primary unsaturated polyester resin or vinyl ester resin composition, whereby the molar ratio of the phenolic inhibitor versus the N-oxyl radical compound is chosen in the range of from 30 : 1 to 1 : 2, preferably of from 20 : 1 to 1 : 1,5, more preferably of from 3 : 1 to 1 : 1. The unsaturated polyester resin or vinyl ester resin compositions according to the invention show a reduced gel-time drift tendency. The present invention further also relates to objects and structural parts prepared from such unsaturated polyester or vinyl ester resin compositions by curing. These can suitably be used in the field of chemical anchoring, construction, roofing, flooring, windmill blades, containers, tanks, pipes, automotive parts, boats, etc.