JPS58122917A - Production of polyester containing sulfonate group - Google Patents

Abstract

PURPOSE:To produce the titled polyester having excellent water solubility, by reacting a specified unsaturated polyester with an acid sulfite to thereby add the acidic sulfite to the unsaturated bonds. CONSTITUTION:An unsaturated polyester is obtained by condensing 1mol of a carboxylic acid component containing at least 1mol% unsaturated dicarboxylic acid (e.g., maleic acid) with 1.5-2mol of an alcohol (e.g., ethylene glycol) at 230-270 deg.C. Then, this unsaturated polyester is mixed and reacted with 0.01- 1.5mol, per mol of unsaturated carboxylic acid, of an acid sulfite (e.g., acid sodium sulfite) at 130-240 deg.C for 10-120min to introduce 3-30mol% sulfonate groups into the polyester. USE:Textile sizing agents, paper processing agents, adhesives, paints, etc.

Description

Detailed Description of the Invention The attempt to introduce sulfonic acid groups into polyester is expected to find new applications in binders with excellent dispersibility for pigments and magnetic materials, anionic functional resins, etc. Research has been conducted for a long time because by introducing a relatively large amount, polyester resin can be made water-soluble and its application to fields such as textile glue, paper processing, and paints can be expanded1. Conventionally, the most well-known method for introducing sulfonic acid groups into polyester is the method of condensation polymerization of sulfonic acid group-containing compounds. It condenses dicarboxylic acids such as isophthalic acid and polyhydric alcohols such as diethylene glycol. The resulting water-soluble polyester is useful as a sizing agent for textiles, a paper sizing agent, and the like.

However, there is a problem that 5-sodicumsulpoisophthalic acid is an expensive compound, and in industrial methods, it is more advantageous to introduce sulfonic acid groups into polyester by using cheaper raw materials. Needless to say.

However, in order to solve this problem, the present inventors have developed a
As a result of repeated research, an unsaturated polyester containing 1 mol% or more of unsaturated dicarboxylic acid in all carboxylic acids and an acidic sulfite are reacted at a temperature of 130 to 240°C,
The present inventors have found that when an acidic sulfite is added to the unsaturated bond, the introduction of the sulfonic acid group is carried out efficiently, and that a water-soluble polyester can be easily produced, and the present invention has been completed.

Since the acidic sulfite used in the present invention is an inexpensive compound that is easily available industrially, the method of the present invention for introducing a sulfonic acid group into polyester using such a raw material is extremely useful industrially.

The unsaturated polyester used in the present invention is prepared by condensing a carboxylic acid and a polyhydric alkyl by a known method.

In the present invention, the proportion of unsaturated dicarboxylic acids in all carboxylic acids must be 1 mol % or more. The presence of such an unsaturated dicarboxylic acid component in the polyester allows addition reaction of acidic sulfite to the unsaturated bonds, making it possible to make the polyester water-soluble. The proportion of unsaturated dicarboxylic acid is 1 mol%
In the following, even though the introduction of the sulfonic acid group itself is possible,
Polyester cannot be made water-soluble.

Examples of the unsaturated dicarboxylic acids include maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid, and the like.

As mentioned above, these unsaturated dicarboxylic acids must account for 1 mol% or more of the total carboxylic acids, but there is no problem even if all the carboxylic acids are unsaturated dicarboxylic acids. Although not available, it is usually used in combination with other carboxylic acids. B carboxylic acids include, for example, succinic acid, malonic acid, dimethylmalonic acid, succinic acid, cultaric acid, adipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylgeltaric acid, azelaic acid,
Sepacic acid, 1,3-cyclohexanedicarboxylic acid, 1
・Ro-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, phthalic acid, terephthalic acid, isophthalic acid, 2,5-norbornanedicarboxylic acid, 1,4-
Examples include naphthalic acid, siphenic acid, 4,4'-oxybenzoic acid, diglycolic acid, thiodipropion, 4,4'-sulfonylcybenzoic acid, 2,5-naphthalene dicarboxylic acid and the like.

The above carboxylic acid may be in the form of a lower alkyl ester or an acid chloride.

Examples of furfur include H ethylene glycol, diethylene glycol, furopylene gelicol, cyfropylene glycol, neopentyl glycol, cyclohexane dimetatool, and pentaerythritol.

In the preparation of unsaturated polyester, a total of 1.5 to 2 mol of alcohol per 1 mol of carboxylic acid is used. Charge the attached reaction vessel at a temperature of 250 to 27
The combination reaction is carried out at 0''C.

Next, the unsaturated polyester is reacted with an acidic sulfite to add the acidic sulfite to the unsaturated bonds in the polyester.

As the acidic sulfite, acidic sodium sulfite is preferred, but acidic potassium sulfite and the like can also be used.

Reaction #'1150-24D"C preferably 170-25
Performed at 0°C. At temperatures below 160°C, the addition reaction hardly progresses and the desired product cannot be obtained. On the other hand, at high temperatures of 240° C. or higher, gelation may occur or the acidic sulfite may decompose. The reaction proceeds almost quantitatively in about 10 to 120 minutes. Usually, acidic sulfite is used in a ratio of 0.01 to 1.5 mol per mol of unsaturated dicarboxylic acid.

No particular catalyst is required in this reaction. Although it is not necessary to use a particular solvent, any solvent may be used as necessary.

Although the content of the sulfonic acid group introduced into the polyester varies somewhat depending on its use, it is generally practical to have #i of about 5 to 60 mol% based on the charged carboxylic acid.

The polyester obtained in this way can be used as fiber glue, paper processing agent, fiber processing agent, adhesive, paint, water-soluble film, fiber,
It is useful as a binder with excellent dispersibility of pigments and magnetic materials, anionic functional resin, etc.

Next, the method of the present invention will be explained in more detail by giving examples.

Example 1 500 equipped with a thermometer, nitrogen inlet pipe, stirrer, and distillation column
In flask #I/, add isophthalic acid + + 6.29
(0,7 mol), maleic anhydride 29.4 F (0,
5 mol), ethylene glycol 57.2 y (0,6
mol), diethylene glycol 63.6 f (0,6
mole) and zinc acetate o, 1y, hydroquinone 0.1y
was charged, the temperature was raised while blowing nitrogen gas, and the mixture was heated at 190° C. for 5 hours.

An unsaturated polyester (A) having an acid value of 2[], 7 (xo11■/y) was obtained.

Next, 51% of sodium acid sulfite was added to the unsaturated polyester.
．． 29 (0.5 mol) and 0.1y of hydroquinone were added and an addition reaction was carried out at a temperature of 180 to 190°C for 60 minutes to obtain an unsaturated polyester containing sodium sulfonate groups.

As a result of analyzing the above (A) and (B) by NMR (solvent DMSO) trap, 6,0 to 7.0 was observed in (3).
Absorption of ppm (double bond based on maleic acid) is (B)
It disappeared, and a new addition (methylene group formed after addition of a double bond) was observed near ``rppm.'' This is due to the addition of acidic sodium sulfite to the unsaturated bond in the maleic acid component of the unsaturated polyester. It was.

Further, Kan 202 was added to 80° C. hot water for 80 d with stirring, but no swelling occurred. On the other hand, when a similar test was conducted for ω), a transparent aqueous solution was obtained after 15 minutes.

Examples 2 to 5 An unsaturated polyester with an acid value of 25.0 (Example 2) produced using fumaric acid instead of maleic anhydride in Example 1 and an unsaturated polyester with an acid value produced using itaconic acid. The saturated polyesters (Example 5) were each reacted with acidic sulfite (IJ) according to Example 1.

In each case, a sodium sulfonate group-containing polyester with good water solubility was obtained.

Example 4 The same experiment as in Example 1 was conducted except that the reaction between the unsaturated polyester and acidic sodium sulfite was changed to 30 minutes at 220 to 250°C.

The same results as in Example 1 were obtained.

Claims (1)

[Claims] The proportion of unsaturated dicarboxylic acids in all carboxylic acids is 1
mol% or more of unsaturated polyester and acidic sulfite
A method for producing a polyester containing a sulfonic acid group, which comprises reacting at a temperature of 50 to 20°C to add an acidic sulfite to the unsaturated bond.