Vinyl ethers in unsaturated polyester resins, vinyl esters and vinyl ester urethanes for structural applications

Process for the preparation of a curable resin composition based on an unsaturated prepolymer, a vinyl ether monomer that can be cross-linked with it and one or more other monomers,

• characterised in that the resin composition is prepared by blending
• (1) an unsaturated prepolymer having an acid number of less than 10 mg of KOH per g,
• (2) a vinyl ether monomer having a general structure according to formula (I) or (II):
• A—CH═CH—O—R (I) or (A−CH═CH−O)n−R′ (II)
• where
• A represents hydrogen or an alkyl group with 1-3 C atoms, and where, if there is more than one A, the individual A groups may be the same or different,
• R either represents an aliphatic group, optionally branched, with 1-20 C atoms, which may also contain a cyclohexyl group and optionally in the carbon chain also one or more O and/or S atoms, which group may be substituted with a functional group chosen from either a hydroxyl group or an amino group, optionally substituted with one or two alkyl groups with 1-3 C atoms,
• or represents a polyethylene glycol or a polypropylene glycol with an average chain length of 2 to 10 glycol units, optionally with an aliphatic group with 1-5 C atoms attached to the chain's free hydroxyl group and
• R′ either is a residual group that corresponds to an aliphatic group, optionally branched, with 2-20 C atoms, which may also contain a 1,4-dimethylenecyclohexyl group, or represents a polyethylene glycol or a polypropylene glycol with an average chain length of 2 to 10 glycol units and
• n is 1, 2, 3 or 4,
• (3) one or more other monomers
• (4) together with any fillers and/or additives that may be required,
• after which the resin composition can be cured by adding a radical-forming system that is unstable in the temperature range from −20° C. to +110° C.