Method for in-mold coating a polyolefin article

A process for producing a polyolefin work piece having a thermoset in-mold coating adhered thereto, comprising:

• a. introducing a polyolefin substrate into a closed mold to form a work piece, the mold temperature being suitable for the activation of a free radical source;
• b. introducing into said closed mold a thermoset coating composition comprising a saturated aliphatic polyester urethane intermediate, an aliphatic or cycloaliphatic saturated portion (meth) acrylate, one or more hydroxy alkyl (meth)acrylates, a polyacrylate ester of an alkylene glycol, one or more vinyl substituted aromatics, and an intiator capable of generating free radicals in said coating composition;
• c . opening said mold and removing said work piece after said coating composition has at least partially cured.

A process for producing a polypropylene work piece having a thermoset in-mold coating adhered thereto, comprising:

• a. introducing a polypropylene substrate heated above its melt temperature into a closed mold of temperature of from about 200° F. to about 250° F. to form a work piece;
• b. introducing into said closed mold a thermoset coating composition comprising a saturated aliphatic polyester urethane intermediate, isobornyl acrylate, hydroxypropyl methacrylate, hexane diol acrylate, styrene, and tertiary butyl perbenzoate;
• c. opening said mold and removing said work piece after said coating composition has at least partially cured.

A molded article as in claim 38 which comprises a coated polypropylene work piece.

A molded polypropylene work piece comprising a thermoset coating bonded thereto, said coating further comprising a component capable of generating free radicals.

A molded polypropylene work piece comprising a thermoset coating bonded thereto, said coating further comprising a saturated aliphatic polyester urethane intermediate, a saturated (cyclo) aliphatic (meth) acrylate, one or more hydroxy alkyl (meth)acrylates, a polyacrylate ester of an alkylene polyol, one or more vinyl substituted aromatics, and an intiator capable of generating free radicals in said coating composition.

A molded polypropylene work piece having a thermoset in-mold coating adhered thereto, made by a process comprising the steps of:

• a. introducing a polypropylene substrate heated above its melt temperature into a closed mold of temperature of from about 200° F. to about 250° F. to form a work piece;
• b. introducing into said closed mold a thermoset coating composition comprising a saturated aliphatic polyester urethane intermediate, isobornyl acrylate, hydroxypropyl methacrylate, hexane diol acrylate, styrene, and tertiary butyl perbenzoate;
• c. opening said mold and removing said work piece after said coating composition has at least partially cured.

A molded polyolefin work piece made by a process comprising the steps of:

• a. introducing a polyolefin substrate into a closed mold to form a work piece, with a mold temperature suitable for the activation of a free radical source;
• b. introducing into said closed mold a thermoset coating composition comprising a saturated aliphatic polyester urethane intermediate, an aliphatic or cycloaliphatic saturated portion (meth) acrylate, one or more hydroxy alkyl (meth)acrylates, a polyacrylate ester of an alkylene glycol, one or more vinyl substituted aromatics, and an intiator capable of generating free radicals in said coating composition;
• c. opening said mold and removing said work piece after said coating composition has at least partially cured.