JPH0377213B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel aromatic polyester having excellent heat resistance and hydrolysis resistance. [Prior Art] Conventionally, aromatic polyesters consisting of aromatic dicarboxylic acid component units such as terephthalic acid component units and isophthalic acid component units and various bisphenol component units have been proposed as heat-resistant aromatic polyesters. [For example, J. Polymer
Science, 40 , 399 (1959), Visokomol.Soyed,
1,834 (1959), Japanese Patent Publication No. 38-15247, British Patent Publication No. 897640, Japanese Patent Publication No. 37-5599, etc.). However, these aromatic polyesters have a drawback of poor hydrolysis resistance at high temperatures. For example, polyisopropylidene-4,4'-diphenylene isophthalate terephthalate, which is already commercially produced, is easily hydrolyzed in an atmosphere where water is present at high temperatures, such as in boiling water, and its performance is greatly reduced. The width decreases. As described above, conventional aromatic polyesters have the disadvantage that they have poor hydrolysis resistance at high temperatures and are susceptible to hydrolysis during molding or use under high temperature conditions. [Problems to be Solved by the Invention] The present inventors have recognized that the conventionally known heat-resistant aromatic polyesters have the above-mentioned problems, and have developed a polyester that has excellent heat resistance and hydrolysis resistance. As a result of searching for aromatic polyesters, aromatic dicarboxylic acid component units having 8 to 16 carbon atoms,
It was discovered that an aromatic polyester consisting of an aromatic dinuclear bisphenol component unit and an aromatic trinuclear bisphenol component unit having a specific structure achieves the above object, and the present invention was achieved. [Summary of the Invention] To summarize the present invention, the present invention comprises: [A] an aromatic dicarboxylic acid component unit having 8 to 16 carbon atoms, and [B] a diol component unit, (a) a general formula [] [wherein, aromatic dinuclear bisphenol component units in the range of 20 to 98 mol%, and (b) general formula [] An aromatic trinuclear bisphenol component represented by [wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ all represent a hydrogen atom or a lower alkyl group] Unit is 2 to 80 mol%
range of aromatic diol component units consisting of and in pentafluorophenol.
The gist of the invention is an aromatic polyester characterized by an intrinsic viscosity [η] of 0.4 dl/g or more measured at 60°C. [Means and effects for solving the problems] The aromatic dicarboxylic acid component unit [A] constituting the aromatic polyester of the present invention is an aromatic dicarboxylic acid component unit having 8 to 16 carbon atoms, and more specifically Specifically, terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalene dicarboxylic acid, 4,
It is an aromatic dicarboxylic acid component unit consisting of 4-biphenyldicarboxylic acid or a mixed component of at least two or more of these. Among these aromatic dicarboxylic acid component units, terephthalic acid component units, isophthalic acid component units, and mixed components thereof are preferable, and in particular, a mixed component consisting of terephthalic acid component units and isophthalic acid component units is preferable. preferable. The aromatic diol component unit [B] constituting the aromatic polyester of the present invention is composed of an aromatic dinuclear bisphenol component unit (a) and an aromatic trinuclear bisphenol component unit (b), The composition of the aromatic diol component unit is 20 to 98 mol%, preferably 20 to 90 mol%, of the aromatic dinuclear bisphenol component unit (a) and the aromatic trinuclear bisphenol component unit (b). is in the range of 2 to 80 mol%. The aromatic trinuclear bisphenol component unit (a) has the general formula [] It is a bisphenol component unit represented by
In the formula,
It represents at least one group selected from the group consisting of a sulfur atom, a sulfinyl group, and a sulfonyl group. Specific examples of the aromatic dinuclear bisphenol component unit include the following compounds. 4,4'-dihydroxydiphenyl, bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)butane, 4,4 '-Cyclohexylidene diphenol, 1-phenyl-1,1-bis(4-hydroxyphenyl)ethane, 4,4'-dihydroxybenzophenone, 4,4'-dihydroxydiphenyl ether, 4,4'- Thiodiphenol, bis(4-hydroxyphenyl) sulfone, and aromatic trinuclear bisphenol component unit (b)
is the general formula [] It is a bisphenol component unit represented by
In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ each represent a hydrogen atom or a lower alkyl group such as a methyl group, an ethyl group, or an isopropyl group. Specific examples of the aromatic trinuclear bisphenol component unit include the following compounds. 1,3-bis(4-hydroxycumyl)benzene, 1,4-bis(4-hydroxycumyl)benzene, 1,3-bis(3,5-dimethyl-4-hydroxycumyl)benzene, 1, 4-bis(3,5-dimethyl-4-hydroxycumyl)benzene, 1,3-bis(3,5-dimethyl-4-hydroxycumyl)benzene, 1,4-bis(3,5-dimethyl- 4-Hydroxycumyl)benzene The aromatic polyester of the present invention has a substantially linear high molecular weight by condensation in which the aromatic dicarboxylic acid component units and the aromatic diol component are arranged alternately to form ester bonds. The terminal end of the molecule may be a carboxyl group, or a hydroxyl group, or the terminal carboxyl group may be esterified with a lower alcohol, or the terminal hydroxyl group may be esterified with a lower alcohol. It may also be esterified with a lower carboxylic acid. Intrinsic viscosity [η] of the aromatic polyester of the present invention
(Value measured at 60℃ in pentafluorophenol)
is in the range of 0.4 dl/g or more, preferably 0.5 dl/g or more. Further, the glass transition temperature of the aromatic polyester is usually 130 to 300°C, preferably
The temperature ranges from 150 to 280°C. The aromatic polyester of the present invention can be produced by the same method as conventionally known aromatic polyesters. For example, the following method can be exemplified. Melt polymerization method The aromatic dicarboxylic acid or its ester-forming derivative and the aromatic diol or its ester-forming derivative are reacted in melt at high temperature,
A method of producing an aromatic polyester by distilling a low-boiling compound produced by the reaction out of the reaction system by operating under reduced pressure. Solution polymerization method Using a high boiling point solvent such as diphenyl ether, benzophenone, metaterphenyl, chlorinated biphenyl, or naphthalene bromide, the aromatic dicarboxylic acid or its ester-forming derivative or its acid halide and the aromatic The diol or its ester-forming derivative is dissolved to form a solution and reacted at high temperature, or if necessary, a tertiary amine, N-
A method of producing aromatic polyester by reacting in the presence of a basic compound such as methylpyrrolidone. Interfacial polymerization method The acid halide of the aromatic dicarboxylic acid is dissolved in an organic solvent, while the aromatic diol is dissolved in water as a metal salt such as a sodium salt, and then both solutions are brought into contact. Therefore, a method of producing an aromatic polyester by reacting the acid halide and the salt of the aromatic diol at the interface. [Effects of the Invention] Since the aromatic polyester of the present invention has superior heat resistance and hydrolysis resistance compared to conventional aromatic polyesters, deterioration during melt molding and use at high temperatures is prevented. [Example] Next, the aromatic polyester of the present invention will be specifically explained with reference to Examples. In the Examples and Comparative Examples, the amounts of raw materials, solvents, catalysts, etc. used are expressed in parts by weight. Further, the glass transition temperature of the aromatic polyester was determined by measuring with a differential scanning calorimeter. Furthermore, the hydrolysis resistance of the aromatic polyester was expressed as the retention rate (%) of the initial value of the intrinsic viscosity [η] after the molded product was immersed in boiling water for 10 days. Example 1 83 parts of terephthalic acid, 83 parts of isophthalic acid, 2,2
-bis(4-acetoxyphenyl)propane 156
1 part, 243 parts of 1,4-bis(3,5-dimethyl-4-acetoxycumyl)benzene, 0.33 part of triphenyl phosphate, and 0.1 part of tetrabutoxy titanate were charged into a reactor, and heated at 250°C with stirring under nitrogen atmosphere. After carrying out the reaction at normal pressure for about 2 hours while distilling off the acetic acid produced at 270°C, the pressure of the reaction system was gradually reduced over about 2 hours and the temperature was raised, and the final pressure was reduced to 0.7 mmHg. At the same time, the temperature was raised to 350℃. Intrinsic viscosity of the aromatic polyester thus obtained [η]
is 0.75dl/g, and its glass transition temperature is
It was 232℃. Furthermore, the hydrolysis resistance of this aromatic polyester was an excellent value of 96%. Comparative Example 1 In Example 1, 1,4-bis(3,5-dimethyl-4-acetoxycumyl)benzene was not used, and 2,2-bis(4-acetoxyphenyl)
An aromatic polyester was produced in the same manner as in Example 1 except that 312 parts of propane was used. The intrinsic viscosity [η] of the obtained aromatic polyester was 0.68 dl/
g, and its glass transition temperature was 186°C.
Furthermore, the hydrolysis resistance of this aromatic polyester was 48%. Examples 2 to 8 Aromatic polyesters were prepared in the same manner as in Example 1, except that aromatic dicarboxylic acid, diacetate of aromatic dinuclear bisphenol, and diacetate of aromatic trinuclear bisphenol were used as shown in Table 1. was manufactured. The intrinsic viscosity [η], glass transition temperature and hydrolysis resistance of the obtained aromatic polyester were as shown in Table 1. [Table] [Table]

Claims (1)

[Scope of Claims] 1 [A] an aromatic dicarboxylic acid component unit having 8 to 16 carbon atoms, and [B] a diol component unit, (a) a general formula [] [wherein, aromatic dinuclear bisphenol component units in the range of 20 to 98 mol%, and (b) general formula [] Aromatic trinuclear bisphenols represented by [In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ all represent a hydrogen atom or a lower alkyl group] The component unit is composed of aromatic diol component units in the range of 2 to 80 mol%, and in pentafluorophenol.
An aromatic polyester characterized by an intrinsic viscosity [η] of 0.4 dl/g or more measured at 60°C.