| 摘要 |
<p>Advanced epoxy resins are prepared from a liquid diglycidyl ether of bisphenol A and bisphenol A which advanced epoxy resins have an equivalent weight in the range of 3,000 to 3,900 and a weight average molecular weight of 13,000 to 17,000.</p><p>These resins are prepared by heating a heating a mixture of (A) a liquid diglycidyl ether of bisphenol A having an average epoxide equivalent weight of from 170 to 195, (B).bisphenol A, (C) a catalytic quantity of one or more catalysts for effecting the reaction between components A and B and (D) a solvent or mixture of solvents such that the exotherm temperature is between 190°C and 210°C; cooling the resuitant reaction mixture to a temperature between 150°C and 185°C and maintaining the tem- ; perature thereat until the desired epoxide equivalent weignt and weight average molecular weight are obtainec: and thereafter quenching the resulting reaction product to a temperature between 90°C and 130°C with (E) one or more solvents.</p><p>In the process of this invention, component A is employed in an amount which comprises from 54 to 62 percent by weight of the combined weight of components A, B, C and D; component B is employed in an amount which comprises from 30 to 35 percent by weight of the combined weight of components A, B, C and D; component C is employed in an amount which comprises from 0.01 to 0.2 percent by weight of the combined weight of components A, B, C and D; component D is employed in an amount which comprises from 5 to 30 percent by weight of the combined weight of components A, B, C and D;</p><p>and component E is employed in an amount which comprises from 30 to 80 percent by weight of components A, B, C, D and E.</p><p>When these advanced epoxy resins are formulated into can coating compositions they result in coatings having good wet and dry adhesion.</p> |
