Aromatic polyesters and a method for producing the same
AssigneeSumitomo Chemical Company, Limited
InventorsItaru Nitta, Kuniaki Asai, Hiroshi Harada
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Abstract
An aromatic polyester superior in heat resistance and mechanical properties and satisfactory in lightness and color tone is provided. The aromatic polyester has resorcinol structure, has the formula (1), ##STR1## wherein R is halogen, C.sub.1 -C.sub.5 alkyl, or phenyl; m is an integer of 0 to 2, and when m is 2, the two substituents represented by R may be different from each other; and gives a powder fraction having a lightness (L value) of 70 or more and a red degree (a value) of 5 or less, which powder fraction is obtained by pulverizing the heat-resistant aromatic polyester, sieving the pulverized polyester by Tyler standard sieves and being allowed to pass through 60-mesh sieve but not 325-mesh sieve.
Claims8
A heat-resistant aromatic polyester resin which has resorcinol structure, has the formula (1), ##STR12## and gives a powder fraction having a lightness (L value) of 80 or more and a red degree (a value) of 3 or less, which powder fraction is obtained by pulverizing the heat-resistant aromatic polyester, sieving the pulverized polyester by Tyler standard sieves and being allowed to pass through 60-mesh sieve but not 325-mesh sieve, which heat-resistant aromatic polyester resin is produced by a method which comprises polymerizing a monomer of a resorcinol diacetate produced by reacting a resorcinol having the formula (14), ##STR13## with acetic anhydride in the presence of a tertiary amine in an amount of 0.02 to 3 parts by weight per 100 parts by weight of resorcinol.
A method for producing a heat-resistant aromatic polyester which has a resorcinol structure of formula (1) ##STR23## and gives a powder fraction having a lightness (L value) of 80 or more and a red degree (a value) of 3 or less, which powder fraction is obtained by pulverizing the heat-resistant aromatic polyester, sieving the pulverized polyester by Tyler standard sieves and being allowed to pass through 60-mesh sieve but not 325-mesh sieve, which comprises polymerizing a monomer of a resorcinol diacetate produced by reacting a resorcinol having the formula (14) with acetic anhydride in the presence of a tertiary amine, ##STR24## wherein the tertiary amine is present in an amount of 0.02 to 3 pans by weight per 100 parts by weight of resorcinol.
Dependencies are inferred from the claim text.