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US 4,055,546 AGranted
Novel thermosetting resins and process for preparing the same
AssigneeHitachi Chemical Company, Ltd.
InventorsTzong Jeng Chu, Susumu Konii
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AssigneeHitachi Chemical Company, Ltd.
InventorsTzong Jeng Chu, Susumu Konii
Estimating the term…
A novel thermosetting resin, the thermoset resin obtained therefrom having such a thermal resistance that the temperature at which the thermoset resin is caused to show a weight loss of 6% by heating at a temperature elevation rate of 10.degree. C. per minute is at least 400.degree. C., is prepared by reacting a specific phenolic resin with a member selected from the group consisting of a silicic acid ester of the formula Si(OR).sub.4 wherein R represents alkyl or aryl and a mixture of a silicic acid ester of the formula as defined above and a titanic acid ester of the formula Ti(OR).sub.4 wherein R has the same meaning as defined above in the presence of an alkaline catalyst while keeping the reaction system in a molten state, to an extent that 20- 70 mole %, based on the phenol present in the starting system to be reacted with said member, of phenolic hydroxyl groups in terms of the amount of phenol, remain unreacted. The thus obtained novel resins of the present invention can be easily set or hardened in accordance with the ordinary manner; namely by mixing with a thermohardening agent such as hexamethylenetetramine and then heating, to give thermoset resins having a superior thermal resistance as compared with the conventional phenolic resins. In addition, the thermoset resins obtained from the novel resins of this invention are excellent in mechanical strength, electrical properties and luster of molded articles.
A thermosetting resin, the thermoset resin obtained therefrom having such a thermal resistance that the temperature at which the thermoset resin is caused to show a weight loss of 6% by heating at a temperature elevation rate of 10.degree. C. per minute is at least 400.degree. C., which comprises a reaction product of a novolak which is obtained by the reaction of a phenol and an aldehyde in the presence of an acid catalyst or a novolak type aryl-modified phenolic resin which is obtained by the reaction of a phenol and an aromatic hydrocarbon-aldehyde condensation initial-stage reaction product with a member selected from the group consisting of a silicic acid ester of the formula Si(OR).sub.4 wherein R represents alkyl or aryl and a mixture of a silicic acid ester of the formula as defined above and a titanic acid ester of the formula Ti(OR).sub.4 wherein R has the same meaning as defined above, said reaction product having such structure that the silicon is or silicon and titanium are bonded directly to oxygens of the phenolic hydroxyl groups while 20 - 70 mole %, based on the amount of phenol present in the starting system to be reacted with said member, of the phenolic hydroxyl groups, in terms of the amount of phenol, are left in the free form.
A process for preparing a thermosetting resin which comprises reacting a novolak which is obtained by the reaction of a phenol and an aldehyde in the presence of an acid catalyst or a novolak type aryl-modified phenolic resin which is obtained by the reaction of a phenol and an aromatic hydrocarbon-aldehyde condensation initial-stage reaction product with a member selected from the group consisting of a silicic acid ester of the formula Si(OR).sub.4 wherein R represents alkyl or aryl and a mixture of a silicic acid ester of the formula as defined above and a titanic acid ester of the formula Ti(OR).sub.4 wherein R has the same meaning as defined above in the presence of an alkaline catalyst while keeping the reaction system in a molten state, said member being employed in an amount of 0.02 - 0.2 molar equivalents, based on the amount of phenol present in the starting system to be reacted with said member.
Dependencies are inferred from the claim text.