JPH093173A - Process for producing polyester having long methylene chain - Google Patents

Abstract

PURPOSE: To obtain an aromatic polyester which exhibits a liquid crystal behavior due to the orientation of polymer at a low temperature by reacting a specified esterified aromatic dicarboxylic acid compound having a long methylene chain with a diol. CONSTITUTION: An aliphatic alcohol (e.g. Unilin 425, a product of Toyo Petrolite Co.) having a molecular weight of 350 to 1,000 is reacted with a cyclic acid anhydride (e.g. trimellitic anhydride) to produce an esterified aromatic dicarboxylic acid compound having a long methylene chain. The obtained dicarboxylic acid compound is then reacted with a diol to give a polyester. An aromatic or aliphatic diol can be used as the diol. Examples of aromatic diol used include hydroquinone and bisphenol A. Examples of aliphatic diol used include ethylene glycol and butane diol. The obtained polyester is useful as, e.g. a component of an adhesive and an additive for improving the activity of a plastic.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for producing a useful polyester which has a long methylene chain and, in the case of a rod-shaped wholly aromatic polyester, can also have thermotropic liquid crystal properties.

[0002]

2. Description of the Related Art Waxes are widely used as lubricants, mold release agents, physical property modifiers for adhesives, etc. for processing plastics and rubber, and low molecular weight polyethylene wax, microcrystalline wax, paraffin wax and the like are common. . However, because of the low molecular weight, the effect of the wax is diminished or disappears during long-term use due to volatilization or elution. For this reason, high molecular weight wax is required. The aromatic polyester has a para-body structure and can have liquid crystallinity by giving it a rod-like shape, which gives high-strength polyester.
This is generally known as engineering plastics and is well known. Generally, very expensive equipment is required for spinning and molding at a high temperature of 200 ° C. or higher. Molding under lower temperature conditions has been desired.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide polyesters which can orient polymers at relatively low temperatures due to the combination of monomers.

[0004]

The present invention has a molecular weight of 350.
It is intended to provide a polyester obtained by reacting aromatic dicarboxylic acids and diols having a long-chain methylene chain-length ester group, which is obtained by reacting an aliphatic alcohol of 1000 or less and a cyclic acid anhydride.

The aliphatic alcohol of the present invention has a molecular weight of 35.
It is a linear or branched aliphatic alcohol of 0 or more and 1000 or less.

The cyclic acid anhydride may be a tricarboxylic acid anhydride, a tetracarboxylic acid anhydride, or other polyvalent carboxylic acid anhydride. Specifically, trimellitic acid anhydride, 1,4,4, and anhydrides may be used. 5-naphthalene tricarboxylic acid, anhydrous 2,6,7-naphthalene tricarboxylic acid, anhydrous 3,
3 ', 4-diphenyltricarboxylic acid, anhydrous 3,3',
4-benzophenone tricarboxylic acid, 1,3,4-cyclopentane tricarboxylic acid, anhydrous 2,2 ', 3-diphenyl tricarboxylic acid diphenyl sulfone-3,3', 4
-Tricarboxylic acid, diphenylisopropylidene-3,
3 ', 4-tricarboxylic acid, 3,4,10-propylene tricarboxylic anhydride, ethylene tricarboxylic acid, pyromellitic dianhydride, biphthalic anhydride, 3,3', 4, anhydrous
4'-benzophenone tetracarboxylic acid, bicyclo [2,2,2] oct-5-ene-2,3-dicarboxylic acid anhydride, bicyclo [2,2,2] oct-7-ene-anhydride
2,3,5,6-tetracarboxylic acid, anhydrous 1,2,6
7-xanthone tetracarboxylic acid, anhydrous 1,2,6,7
-Thioxaton tetracarboxylic acid, anhydrous 1,2,6,7
-Anthraquinone tetracarboxylic acid, perylene tetracarboxylic acid anhydride and the like can be exemplified.

The synthesis of dicarboxylic acid monomers having a long-chain methylene chain-length ester group can be obtained by a usual esterification reaction between an aliphatic alcohol and a cyclic acid anhydride.
Regarding the reaction temperature condition, a temperature exceeding the melting point of the aliphatic alcohol, that is, 50 ° C. to 200 ° C. is desirable. Further, since alcohol can serve as a reaction solvent, it can be synthesized without a solvent, but the reaction may be carried out in an organic solvent in order to control the reaction rate. By the esterification reaction, for example, a derivative in which the position of the carboxyl group of anhydrous benzenetetracarboxylic acid is the para position or the meta position is obtained. In order to control the orientation of the obtained polymer, it is preferable to separate and purify the para form and the meta form. It is preferable to use a mixture of para-form and meta-form without purification separation for ordinary polyester synthesis because the purification step can be omitted.

As the diols, aromatic or aliphatic diols can be used. Examples of the aromatic diol include hydroquinone, biphenol, bisphenol A, bisphenol F, bisphenol B, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) ether, bis (3-). Hydroxyphenyl) methane, bis (3-hydroxyphenyl) ether, bis (2-hydroxyphenyl) methane, bis (2-hydroxyphenyl) ether and the like. Examples of the aliphatic diol include ethylene glycol, triethylene glycol, butane diol, hexane diol, diethylene glycol, polyethylene diol, polyester diol, polybutadiene diol, etc., but are not limited to these and any diol can be used. . In addition, glycerin having a trifunctional hydroxyl group or the like can be used depending on the case.

The obtained polyester can be used as a component of oxidation, an adhesive agent, an additive for improving the activity of plastics, a pigment dispersion aid for pigment dispersions and resin masterbatches, and a compatibility imparting agent for various materials. It can also be used as a mixture with general polymers such as polystyrene, polyvinyl chloride, polyethylene, polypropylene, polyester, polyamide and polyether. It can also be used as a dispersion aid for two or more kinds of polymers having poor dispersibility.

[0010]

EXAMPLES The present invention will be described below with reference to examples. In the examples, parts represent weight. Example 1 Synthesis of dicarboxylic acid [A] Pyromellitic anhydride 19 parts Unilin 425 (manufactured by Toyo Petrolite Co., number average molecular weight 460, aliphatic alcohol) 81 parts The above mixture was heated and stirred at 120 ° C. for 5 hours. The end point of the reaction was confirmed by the absence of acid anhydride absorption around 1780 cm ^{−1 in the} infrared absorption spectrum. The product is a reactive ester compound because it has an ester group absorption at 1730 cm ^{−1 and} a carboxyl group absorption at 1704 cm ⁻¹ as a result of infrared absorption spectrum, and is a milky white waxy solid with a melting point of 80 ° C. Met.

Synthesis of polyester Dicarboxylic acid [A] 17.5 parts Biphenol 2.8 parts Paratoluenesulfonyl chloride 7.4 parts Picoline 60 parts The above mixture is slowly heated to 100 ° C. with stirring and then at 100 ° C. The reaction was carried out at the temperature for about 5 hours. The product was purified by precipitation with methanol and the solvent was removed. The number average molecular weight of the obtained aromatic polyester was about 3000 based on the result of gel permeation chromatography (GPC). Liquid crystal behavior of the obtained polyester could be observed at 90 ° C. by a heating polarization microscope, and it was found that the polymer was oriented. Further, even when cooled, the orientation was maintained, and the behavior as a liquid crystal polyester similar to general polyarylene was confirmed.

Example 2 Synthesis of dicarboxylic acid [B] Pyromellitic dianhydride 13 parts Uniline 700 (manufactured by Toyo Petrolite Co., number average molecular weight 700, aliphatic alcohol) 87 parts

The above mixture was heated and stirred at 120 ° C. for 5 hours. The end point of the reaction is 1780 cm of infrared absorption spectrum
It was confirmed that there was no absorption of acid anhydride near ^-1 . The product was a milky waxy solid with a melting point of 95 ° C. Synthesis of polyester Dicarboxylic acid [B] 24.3 parts Biphenol 2.8 parts Paratoluenesulfonyl chloride 7.4 parts Picoline 60 parts The above mixture is slowly heated to 100 ° C. with stirring, and then at a temperature of 100 ° C. The reaction was carried out for 5 hours. The product was purified by precipitation with methanol and the solvent was removed. The obtained aromatic polyester had a number average molecular weight of about 3,500 based on the result of gel permeation chromatography (GPC). The obtained polyester was oriented at 110 ° C. by a heating polarization microscope, and the liquid crystal behavior could be observed. Moreover, the liquid crystal behavior was confirmed by maintaining its orientation even when cooled.

Example 3 Synthesis of dicarboxylic acid [C] trimellitic anhydride 21.5 parts Unilin 700 (manufactured by Toyo Petrolite Co., number average molecular weight 700, aliphatic alcohol) 78.5 parts The above mixture was mixed at 120 ° C. for 5 minutes. The mixture was heated and stirred for hours. The end point of the reaction was confirmed by the absence of acid anhydride absorption around 1780 cm ^{−1 in the} infrared absorption spectrum. The product has a melting point of 95
It was a milky white waxy solid at 0 ° C. Polymer synthesis Dicarboxylic acid [C] 23.9 parts Biphenol 2.8 parts Paratoluenesulfonyl chloride 7.4 parts Picoline 60 parts The above mixture is slowly warmed to 100 ° C. with stirring, then at a temperature of 100 ° C. The reaction was carried out for 5 hours. The product was purified by precipitation with methanol and the solvent was removed. The obtained aromatic polyester had a number average molecular weight of about 2,500 according to the result of gel permeation chromatography (GPC). The liquid crystal behavior of the obtained polyester was observed by a heating polarization microscope at 110 ° C. due to the orientation of the polymer. It was also found that the orientation is maintained even when cooled.

Example 4 Synthesis of dicarboxylic acid [D] Pyromellitic dianhydride 9.5 parts Unilin 425 (manufactured by Toyo Petrolite Co., number average molecular weight 460, aliphatic alcohol) 40.5 parts Xylene 50 parts The above mixture The mixture was heated and stirred at 100 ° C. for 5 hours. The end point of the reaction was confirmed by the absence of acid anhydride absorption around 1780 cm ^{−1 in the} infrared absorption spectrum. The product was cooled to room temperature and the solvent was removed in a vacuum oven. The obtained aliphatic ester was a white waxy solid having a melting point of 80 ° C. When polyester was synthesized in the same manner as in Example 1, a predetermined aromatic polyester was obtained when biphenol was used. The number average molecular weight was about 3200. It was confirmed with a polarizing microscope that the polyester of the present invention exhibits liquid crystal behavior depending on the orientation of the polymer. The results of synthesizing other polyesters are also shown in the table below.

Results of polyester synthesis ────────────────────────────────── Acid anhydride Alcohol diol Liquid crystal temperature (℃ ) ────────────────────────────────── BT Unilin 425 BP 90 BT Unilin 550 BP 100 BT Unilin 700 BP 110 TA Unilin 425 BP 110 TA Unilin 700 BP 110 BT Unilin 425 BA-TA Unilin 425 BA-BT Unilin 425 EG-TA Unilin 425 EG-──────────────────── ───────────── BT: anhydrous benzenetetracarboxylic acid, TA: anhydrous benzenetricarboxylic acid BP: bisphenol, BA: bisphenol A EG: ethyl Glycol UNILIN 425: MW = 460, Unilin 550: MW = 550, UNILIN 700: MW = 700 liquid crystallization temperature: The color tone wearing polarized in a heating-type polarizing microscope visually evaluated.

[0017]

According to the present invention, a polyester having a long chain as a side chain can be obtained. Furthermore, by using a diol such as biphenol, it was possible to obtain an aromatic polyester which exhibits liquid crystal behavior derived from the orientation of the same polymer as the liquid crystal polyester at low temperature.

Claims (1)

[Claims] 1. A polyester produced by reacting an aromatic dicarboxylic acid having a long-chain methylene chain-length ester group and a diol obtained by reacting an aliphatic alcohol having a molecular weight of 350 to 1000 with a cyclic acid anhydride. Method.