JPS60221422A - Production of polyester copolymer - Google Patents

Abstract

PURPOSE:To obtain the titled polymer having melt anisotropy, easily from an inexpensive raw material without necessitating complicate process, by contacting a polyester with a specific hydroxycarboxylic acid in the presence of an acylation agent. CONSTITUTION:The objective polymer having a logarithmic viscosity (etainh) of >=0.3dl/g can be produced by contacting (A) 5-95mol% oligo-ester or polyester (preferably polyethylene terephthalate) composed of the recurring unit of formula (R<1> is 4-20C bivalent alicyclic hydrocarbon group or 1-40C bivalent aliphatic hydrocarbon group; R<2> is 2-40C aliphatic hydrocarbon group, 4-20C alicyclic hydrocarbon group, etc.) with (B) 95-5mol% hydroxycarboxylic acid of formula HO-R<3>-COOH (R<3> is 6-20C bivalent aromatic hydrocarbon group) (preferably p- hydroxybenzoic acid) in the presence of (C) an acylation agent such as acetic anhydride, and polymerizing the produced copolymerized oligomer.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a novel method for producing melt anisotropic copolyester. The process is also very simple because the step of isolating acetoxybenzoic acid is omitted. This invention relates to a method for producing melt anisotropic copolyester.

[Prior art]

In recent years, whether fibers, films or molded products,
There is an increasing demand for materials with excellent rigidity, heat resistance, and chemical resistance. Although polyester has become widely accepted for use in general molded products, many polyesters have poor mechanical properties such as flexural modulus, so they are not suitable for applications that require high strength. In order to improve the mechanical properties of this machine, it is known to blend reinforcing materials such as calcium carbonate and glass fiber.
Because the specific gravity of the material increases.

The lightweight advantage of plastic is diminished.

Furthermore, during molding, the molding machine is subject to severe wear, which poses many practical problems. In recent years, liquid crystalline polyester has attracted attention as a polyester that does not require a reinforcing material and is suitable for applications that require high strength. The Journal Op.
Polymer Science Polymer Chemistry Edition, Vol./4 (Reg. 7), page ZO4t, and Japanese Patent Publication No. Sho F4-/Lr01t 2W, J.

This was after Jackson announced a thermoplastic liquid crystal polymer consisting of polyethylene terephthalate and acetoxybenzoic acid. In this work, Jackson showed that this liquid crystalline polymer had new possibilities for polyethylene terephthalate resin.

[Problem that the invention seeks to solve]

However, although these production methods use acetoxybenzoic acid as a raw material, acetoxybenzoic acid is generally produced by reacting hydroxybenzoic acid with acetic anhydride, followed by isolation and purification.

In order to convert hydroxybenzoic acid into acetoxybenzoic acid, a temporary and complicated process is required, and it is not desirable to use acetoxybenzoic acid as a raw material in terms of equipment and cost. In view of such points, the present inventors conducted intensive studies and found that acetoxybenzoic acid can be isolated and purified using hydroxybenzoic acid as a raw material without requiring the above-mentioned complicated process. We have discovered a method for easily fabricating anisotropic polyether T-fibers without having to do so.

[Means for solving problems]

That is, 1. The gist of the present invention is the general formula
．． A divalent aliphatic hydrocarbon group having 7 to 4 carbon atoms or a divalent aromatic hydrocarbon group having 6 to 20 carbon atoms forming an aromatic ring (however, hydrogen in the aromatic ring of the aromatic hydrocarbon group The atom represents a halogen atom (optionally substituted with an alkyl group or alkoxy group with a carbon number of /. alicyclic hydrocarbon group with a carbon number of 6 to form an aromatic base
~2Q monovalent aromatic hydrocarbon group (however, the hydrogen atom, hahalogen atom, carbon number/
(may be substituted with an alkyl group or an alkoxy group), or a divalent group of a polyalkylene oxide of the molecular child goNzooo]; R”−0 0 0 H −−・・−・−・−
(IIJ [In the formula, Ha has 6 carbon atoms forming an aromatic ring.
~2θ λi aromatic hydrocarbon group (however, the hydrogen atom of the aromatic ring of the aromatic hydrocarbon group may be substituted with a halogen atom, an alkyl group having 1 to 1 carbon atoms, or an alkoxy group)
], the polymerization is carried out after contacting the molar ratio of donoxycarboxylic acid 9j-t in the presence of an acylating agent to form a copolymerized oligomer, and at least the logarithmic viscosity (?1ffly) is θ, The present invention resides in a method for producing a copolymerized polyester characterized by producing a copolymerized polyester having a molecular weight of 4171 or more.

Next, to explain the present invention in detail, the present invention has a forefoot general formula (1
The reaction is carried out by bringing the poly or oligoester represented by ) into contact with the hydroxycarboxylic acid represented by the forefoot general formula in the presence of an acylating agent. 11) Production of copolymerized oligoester with acyloxycarboxylic acid of poly or It is carried out at a temperature of 30° C. or higher and 300° C. or lower.

If the contact is carried out at 110°C or lower, the first stage reaction may occur simultaneously. The first step of carrying out one acidolysis (ester exchange reaction) reaction is /! θ~3! The temperature is θ°C, preferably 200 to 300°C, but in this case as well, the reaction 111) may occur simultaneously in addition to the reaction Il).

The third step of carrying out the polymerization reaction is carried out at 200 to 3jO<0>C, preferably at 2jO to 3Q[theta]<0>C. Furthermore, the first and second stage reactions are generally carried out under normal pressure or increased pressure.

The third stage reaction is carried out under reduced pressure and vacuum. It is therefore necessary to distill off the carboxylic acid and unreacted acylating agent in the first and second stages. It goes without saying that an acylation catalyst, transesterification catalyst, and polymerization catalyst may be added as necessary. Note that the molar ratio of the raw material poly or oligoester used in the present invention and the hydroxycarboxylic acid is j to 9.
It's evening.

Forepaw oligo consisting of repeating units represented by general formula (1)/
l Esters or polyesters are prepared from dicarboxylic acids and diols.

As the dicarboxylic acid, a carboxylic acid HOOORlooooH... (JA) represented by the general formula U) and its ester are used. Specific examples of the carboxylic acid include terephthalic acid, methoxyterephthalate, etc. acid, ethoxyterephthalic acid.

Fluoroterephthalic acid, chloroterephthalic acid.

Methyl terephthalic acid, isophthalic acid, phthalic rIR.

Methoxyinctaric acid, diphenylmethane, terdicarbon rR, diphenylmethane 3. j/-dicarboxylic acid, diphenyl ether g, 4t'-dicarboxylic acid, diphenyl-g, 4t'-dicarboxylic acid, naphthalene-2,
6-dicarboxylic acid, naphthalene/,! Dicarboxylic acid, naphthalene/, 4t dicarboxylic acid, adipic acid, sepacic acid, azelaic acid, speric acid, dodecane dicarboxylic acid, 3-methyl azelaic acid, geltaric acid, conotaric acid, cyclohexane/, 4t dicarboxylic acid, cyclohexane/, Examples include 3-dicarboxylic acid and cyclopentane-3-dicarboxylic acid, but these may be used in combination, and any of those represented by the general formula 1) can be used.

Further, as the diol, a compound represented by the general formula is used.

HOR" OH...- (JV) Specific examples include ethylene glycol, /, j-propanediol, and l, 2-propanediol.

/, 4t-7'tanediol, neopentyl glycol, /, 4-hexanediol, /, /λ-dodecanediol, 7.3-butanediol, cyclohexane/, 4
t-diol, cyclohexane/, 3-diol cyclohexane/, cosiol, cyclobenyltane/, 3-diol%/, 4t-cyclohexane dimetatool, p-
xylylene diol, da, 4t'-thiodiphenol,
4t, 4t'-methylene diphenol, tertiary hydroxybiphenyl, hydroquinone, resorcinol,
Examples include dasulfonitaline diol, chlorhydroquinone, 4t, a'-cyclohexylidene diphenol, diethylene glycol, debutylene glycol, polyethylene glycol-N, polytetramethylene glycol, etc., but these may be used in combination. Any of the general formulas can be used.

As the polyester or oligoester represented by the formula (1) used in the present invention, any of those represented by the general formula (IJ) can be used, but polyethylene tere-7-talate is used because of its easy availability.

Polybutylene terephthalate and oligomers thereof are preferred, particularly polyethylene terephthalate and oligomers thereof.

Hydroxycarboxylic acids represented by the general formula (Il) KO-RLCOOH (IIJ) include hydroxybenzoic acid, metahydroxybenzoic acid, Rh 2-hydroxy6-naphthoic acid, /-hydroxyonaphthoerI
RTh /-Hydroxygoonaftoe! L 4t-Hydroxy 3-chlorobenzoic M.

Goo Hydroxy 3. ! -Dimethylbenzoic acid, Schringer@, vanillic acid, and terhydroxy 3-one are preferred, but any of those represented by the general formula α can be used, or they can be used in combination. It is.

In addition, as the acylating agent, acetic anhydride, propionic anhydride, butyric anhydride, benzoic anhydride, etc. are used, but any generally usable acylating agent can be used; And acetic anhydride is typical from the viewpoint of cost.

The amount used is usually O for hydroxycarboxylic acid.
1 t mole or more, preferably θ, ri! More than double the molar amount is used.

Furthermore, the copolymerized polyester according to the present invention can be prepared by introducing a small amount of a copolymerized component depending on various purposes.

〔Example〕

EXAMPLES The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to the following Examples unless the gist of the invention is exceeded.

The logarithmic viscosity (η1 system h) was measured at 30° C. at a concentration of 0.1 i/dt using a mixed solvent of tetrachloroethane/phenol=/// (weight ratio>o) as a viscosity solvent.

The elastic modulus (sonic modulus) was measured using a strand made by melt extrusion using a melt indexer (Takara Kogyo Nashi), and a new Dynamic Modulus Tester PPM-JR manufactured by Toyo Seiki Co., Ltd. The velocity of sound (V) t- was measured and calculated using Laplace's equation shown below.

E=ρV! E: Sonic modulus ρ: Density (measured with a density gradient tube) V: Sonic velocity Example/Polyethylene terephthalate oligomer (ηgth 10.10 dt/11) j7. t
g i (0.3 mol) and p-hydroxybenzoic@62
．． / g (o, 4tzmo/I/) acetic anhydride 4l-jt
, 977 and stannous acetate θ, Oj 6 ji were charged into a polymerization tube equipped with a stirrer, and after purging with nitrogen three times,
Polymerization tube - f i j Placed in an oil bath at 0°C and stirred for 1 hour.
1 hour at 100℃ without allowing acetic acid to distill out, and then 24t.
The mixture was stirred at θ°C for 1 hour.

Furthermore, the oil bath was raised to -27,j°C, and the pressure was gradually reduced while distilling acetic acid, and after 30 minutes, the temperature was set to θ, ir, and ag. Next, the polymer thread t' was returned to normal pressure with N*, and after adding zinc acetate dihydrate 0.01≦9, The polymerization was completed by stirring for 6 hours under a vacuum of /lii.

The yi and th of this polymer are θ, 77 at/j! The sonic modulus was JOGpa.

Examples - polyethylene terephthalate polymer (1) iJlh=
0. ≦4t dt/i) at normal pressure at 0 °C/
The reaction was carried out for -27j'Q/hour at normal pressure, and for 27j'Q/hour under vacuum (Qo, 21IIIHy).
The same reaction as in Example 1 was carried out except that C4 was polymerized for a period of time to obtain a polymer having Blth =0.6/dL/l.

The sonic modulus of this polymer was /4tGpa◎ [Effects of the Invention] As described above, according to the method of the present invention, a copolymerized polyester with excellent physical properties can be obtained through a simplified process.

Applicant: Mitsubishi Chemical Industries, Ltd. Cf7λl

Claims (1)

[Claims] (1) In the general formula [wherein R1 is a tetravalent alicyclic hydrocarbon group having carbon numbers up to 20, a monovalent aliphatic hydrocarbon group having carbon numbers up to aO, or carbon forming an aromatic ring. A monovalent aromatic hydrocarbon group having a number of t to -〇 (However, the hydrogen atom of the aromatic ring of the aromatic hydrocarbon group may be substituted with a halogen atom, an alkyl group or an alkoxy group with a carbon number of /~d) good) and H2 is the carbon number λ
~aoq) Monovalent aliphatic hydrocarbon group, carbon number dal-20
An oa-valent alicyclic hydrocarbon group, a monovalent aromatic hydrocarbon group having 4 to -0 carbon atoms forming an aromatic ring (however, the hydrogen atom in the aromatic ring of the aromatic hydrocarbon group is a halogen atom, may be substituted with an alkyl group or alkoxy group having 7 to 4 carbon atoms), or a polyalkylene oxide group with molecules trθ to tooo and a divalent aromatic hydrocarbon group having the general formula (10% formula% , the hydrogen atom of the aromatic ring of the aromatic hydrocarbon group may be substituted with a halogen atom, an alkyl group having 7 to 2 carbon atoms, or an alkoxy group) ] hydroxycarboxylic acid represented by are brought into contact in the presence of an acylating agent to form a copolymerized oligomer, and then polymerization is carried out.
A method for producing a copolyester, characterized by producing the above copolyester.