摘要:
A low-cost way to modulate the reactivity and acid number of polyetherester thermoset resins is disclosed. 'Beginning' and 'end' methods for making dicyclopentadiene (DCPD)-modified polyetherester resins are described. The 'beginning' method comprises first heating a polyether, DCPD, a diol, an insertion catalyst, and a carboxylic acid derivative to produce a mixture that contains the polyether and a DCPD-diol diester adduct. Increasing the temperature causes insertion of the DCPD-diol diester into the polyether to give a DCPD polyetherester resin. The 'end' method reacts a polyetherester resin made by insertion with DCPD to give a DCPD polyetherester resin. Compared with DCPD polyester resins, those of the invention give more flexible thermosets. Compared with unmodified polyetherester resins, the DCPD polyetherester resins offer formulators more control over curing, which eliminates mold distortion and shrinking or cracking of thermoset parts. Thermosets from blends of the subject resins and DCPD polyester resins show synergistic property improvements compared with thermosets from either resin alone.
摘要:
A process for making polyetherester resins is disclosed. The process comprises reacting a polyether with a diol diester in the presence of a catalyst that promotes random insertion of the diester into carbon-oxygen bonds of the polyether to produce the polyetherester resin. The process of the invention offers many advantages, including higher resin yields, reduced by-product generation, and the ability to make resins with low color and low acid numbers. The resins are useful for making polyetherester thermosets.
摘要:
A process for making high-performance polyetherester resins and thermosets is disclosed. A polyether polyol reacts with a dicarboxylic acid or anhydride in the presence of an insertion catalyst to produce an acid-terminated polyetherester resin. Reaction of this resin reacts with a primary diol or a diepoxy compound gives a chain-extended polyetherester resin that can be cured with a vinyl monomer to produce a high-performance polyetherester thermoset. Properties of the thermosets rival or exceed those or more expensive high-performance iso and vinyl ester resins.