Preparation of epoxy resins
First Claim
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1. In a method for preparing glycidyl derivatives of compounds having at least one aromatic hydroxyl group or aromatic amine group per molecule by reacting at least one compound having at least one aromatic hydroxyl group or aromatic amine group per molecule with an excess of at least one epihalohydrin in the presence of an alkali metal hydroxide and subsequently recovering the glycidyl derivative product;
- the improvement which comprises(1) conducting the reaction in the presence of an organic solvent which codistills with water and said epihalohydrin at a boiling point below the boiling point of the lowest boiling compound among the components in the reaction mixture;
(2) conducting the reaction under a reduced pressure sufficient to provide a distillate with a boiling point of from about 45°
C. to about 80°
C.;
(3) employing said alkali metal hydroxide as an aqueous solution and adding said aqueous alkali metal hydroxide in a continuous or intermittent manner over a period of from about 0.5 to about 10 hours;
(4) continuously removing water by means of codistillation at a rate such that the water content in the reaction mixture is less than about 6 percent by weight;
(5) separating the water from the codistillate and returning the solvent and epihalohydrin to the reaction mixture.
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Abstract
Epoxy resins are prepared by reacting an excess of an epihalohydrin with a phenolic hydroxyl-containing compound in the presence of the incremental addition of a basic catalyst while removing water by codistilling with a solvent and epihalohydrin.
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Citations
12 Claims
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1. In a method for preparing glycidyl derivatives of compounds having at least one aromatic hydroxyl group or aromatic amine group per molecule by reacting at least one compound having at least one aromatic hydroxyl group or aromatic amine group per molecule with an excess of at least one epihalohydrin in the presence of an alkali metal hydroxide and subsequently recovering the glycidyl derivative product;
- the improvement which comprises
(1) conducting the reaction in the presence of an organic solvent which codistills with water and said epihalohydrin at a boiling point below the boiling point of the lowest boiling compound among the components in the reaction mixture; (2) conducting the reaction under a reduced pressure sufficient to provide a distillate with a boiling point of from about 45°
C. to about 80°
C.;(3) employing said alkali metal hydroxide as an aqueous solution and adding said aqueous alkali metal hydroxide in a continuous or intermittent manner over a period of from about 0.5 to about 10 hours; (4) continuously removing water by means of codistillation at a rate such that the water content in the reaction mixture is less than about 6 percent by weight; (5) separating the water from the codistillate and returning the solvent and epihalohydrin to the reaction mixture. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
- the improvement which comprises
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Litigation Data
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Current AssigneeThe Dow Chemical Company (Dow, Inc.)
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Original AssigneeThe Dow Chemical Company (Dow, Inc.)
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InventorsPham, Ha Q., Bertram, James L., Wang, Chun S.
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Primary Examiner(s)NOT, DEFINED
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Application NumberUS06/523,910Time in Patent Office546 DaysField of Search528/95, 528/99, 528/409, 525/507, 525/519, 549/514, 549/517US Class Current528/95CPC Class CodesC08G 59/063 with epihalohydrinsC08G 59/10 of polyamines with epihaloh...
