초록 ▼

Discloses a technique for modifying an epoxy resin by reacting with addition copolymerizable monomer in the presence of at least 3% of benzoyl peroxide at about 110°C. to 120°C., or the free radical initiating equivalent thereof. The reaction mixture obtained contains: (a) unreacted epoxy resin; (b)

Discloses a technique for modifying an epoxy resin by reacting with addition copolymerizable monomer in the presence of at least 3% of benzoyl peroxide at about 110°C. to 120°C., or the free radical initiating equivalent thereof. The reaction mixture obtained contains: (a) unreacted epoxy resin; (b) graft polymer; and (c) associatively formed but ungrafted addition polymer. The graft polymer is formed from the epoxy resin by the grafting of addition polymer onto aliphatic backbone carbons of the epoxy resin, such grafting being at carbons that have either one or two hydrogens bonded thereto in the ungrafted state. The process is useful for making polymer blends for coating compositions, and particularly, coatings for cans for foods and beverages, especially for beer. The coating compositions may be aqueous dispersions ready for spray application, or concentrate that can be made up readily into aqueous sprayable coating compositions. Solvent vehicles may also be used.

대표청구항 ▼

An associatively-formed resinous blend that is dispersible in a basic aqueous vehicle, and that has an oxirane content of no more than 3%, comprising: (a) carboxylic acid-functional graft polymer, (b) ungrafted carboxylic acid-functional addition polymer, and (c) ungrafted aliphatic or aromatic 1,2-

An associatively-formed resinous blend that is dispersible in a basic aqueous vehicle, and that has an oxirane content of no more than 3%, comprising: (a) carboxylic acid-functional graft polymer, (b) ungrafted carboxylic acid-functional addition polymer, and (c) ungrafted aliphatic or aromatic 1,2-epoxy diepoxide resin; said graft polymer being a 1,2-epoxy diepoxide resin component onto which is grafted an addition polymer component, said graft polymer and said ungrafted addition polymer containing carboxylic acids units furnishing carboxyl groups that contribute at least 5% of the weight of said blend, said graft polymer being formed by the reaction of a 1,2-epoxy diepoxide resin and ethylenically unsaturated monomer in the presence of at least 3% of benzoyl peroxide by weight based on monomer, or under equivalent free radical initiating conditions for the reaction including the use of a peroxide initiator, at a temperature in the range from about 80°C. to 200°C., the grafting between said addition polymer component and said epoxy resin component being at aliphatic backbone carbon atoms of said epoxy resin component, to the extent of at least 1½weight parts of said addition polymer component per 100 weight parts of said epoxy resin equivalent in the blend, the epoxy resin component of said graft polymer having an initial molecular weight of from about 350 to about 20,000 and with said ungrafted epoxy resin constituting from about 5 to 90% of said blend by weight, the acid-functionality of the reaction product composition being sufficiently high to establish the blend as a dispersion in an aqueous medium containing a base that ionizes the acid-functional polymers.