Fire retardant polyester resins
AssigneeJefferson Chemical Company, Inc.
InventorsHoward Paul Klein, Harold George Waddill
Life of this patent
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Abstract
A polymerizable fire retardant unsaturated polyester resin composition is prepared by reacting a dicarboxylic acid with a polyhydric compound and an effective amount of 4,5-dibromohexahydrophthalic anhydride or its corresponding acid. The resulting unsaturated polyester resin composition when mixed with a polymerizable monomer containing terminal unsaturation and cured exhibits improved flame resistance at low bromine concentrations.
Claims13
A process for making a fire retardant infusible cured polyester bromine-containing resin comprising the steps of:
- initially forming a bromine containing polyester resin having ester groups derived from an ethylenically unsaturated dicarboxylic acid or acid anhydride in the polyester chain by simultaneously mixing and reacting
- a. polyhydric alcohol selected from the group consisting of aliphatic glycols having from 2 to 10 carbon atoms and aliphatic glycol ethers having from 4 to 20 carbon atoms;
- b. an ethylenically unsaturated dicarboxylic acid or acid anhydride selected from the group consisting of maleic acid, maleic anhydride, fumaric acid, itaconic acid, and mixtures thereof, and
- c. a 4,5-dibromohexahydrophthalic compound selected from 4,5-dibromohexahydrophthalic anhydride and 4,5-dibromohexahydrophthalic dicarboxylic acid at a temperature of from about 100.degree.C to about 175.degree.C to form a product having an acid number within the range of about 0 to 40 mg. KOH/g., wherein the dicarboxylic acid or anhydride (b) and the 4,5-dibromohexahydrophthalic compound (c) are collectively employed in an amount such that there is approximately one hydroxyl equivalent based on the polyhydric alcohol (a) per carboxyl equivalent and wherein the 4,5-dibromohexahydrophthalic compound (c) is present in an amount of from about 5 to about 25 mole percent of the total dicarboxylic acids (b) and (c);
- mixing the resulting polyester resin with a cross linking agent which is a polymerizable monomer having terminal ethylenic unsaturation;
- and,
- curing the resultant mixture to produce said fire retardant infusible cured polyester.
A curable bromine-containing unsaturated polyester resin mixture consisting essentially of:
- a polymerizable monomer cross-linking agent having terminal ethylenic unsaturation;
- and,
- a polymerizable bromine-containing resin having ester groups derived from an ethylenically unsaturated dicarboxylic acid or acid anhydride in the polyester chain and being the reaction product of
- a. a polyhydric alcohol selected from the group consisting of aliphatic glycols having from 2 to 10 carbon atoms and aliphatic glycol ethers having from 4 to 20 carbon atoms;
- b. an ethylenically unsaturated dicarboxylic acid or acid anhydride selected from the group consisting of maleic acid, maleic anhydride, fumaric acid, itaconic acid and mixtures thereof, and
- c. a 4,5-dibromohexahydrophthalic compound selected from 4,5-dibromohexahydrophthalic anhydride and 4,5-dibromohexahydrophthalic dicarboxylic acid wherein the dicarboxylic acid or anhydride (b) and the 4,5-dibromohexahydrophthalic compound (c) are collectively employed in an amount such that there is approximately one hydroxyl equivalent based on the polyhydric alcohol (a) per carboxyl equivalent, wherein the 4,5-dibromohexahydrophthalic compound (c) is present in an amount of from about 5 to about 25 mole % of the total dicarboxylic acids (b) and (c) and wherein the reaction is accomplished at temperatures of 100.degree.C to 175.degree.C.
Dependencies are inferred from the claim text.