CS239971B1 - Water-soluble polyesther resin and its processing method - Google Patents

Abstract

Water-soluble polyester resins and process for their preparation

Description

The invention discloses a composition and a process for the preparation of water-soluble polyester resins suitable as binders of special types of paints or as binders of certain technical compositions.

Polyester resins have found good application in many industrial areas due to their widely variable properties. They are mostly used in the form of solutions in organic solvents for paints, low viscosity solvent-free types for casting compounds, solid types for molding compounds and powder coatings. Water solubility is difficult to achieve for them, usually with a disproportionate deterioration of the other properties. However, for some applications this condition of good solubility is crucial, even at room temperature and very low concentrations. Water solubility is often achieved by the addition of organic oxygen solvents, which, however, presents problems in applications where the elimination of all organic volatile components is a precondition for use.

It has now been found that good water solubility can be achieved with polyester resins based on condensation products of polyhydric carboxylic acids with divalent or trivalent alcohols or functional derivatives of these components, the composition and process of which are the subject of the present invention. The polyester resins contain from 8 to 83% by weight of ester-linked

% 239 971 residues of divalent alcohols having 2 to 28 carbon atoms, 15 to 90 wt. ester-bonded residues of compounds of the formulas

R - (C00) -, - (000) - R - (C00 * M ⁺ ) x λ y and optionally up to 15 wt. ester-linked residues of compounds of the general formula

- (00C) _x -R-SOfM * or

- (00C) - R - (C00 'M ⁺ ).

λ * j

In these formulas, R represents a benzene dicarboxylic acid residue.

unsaturated acyclic carboxylic acids having 2 to 4 carbon atoms or polymeric carboxylic acids with a maximum molecular weight of 1 500. The index x may have values of 1 to 8, y values of 1 to 7, M is sodium, potassium or alkylaraonium cation of the (R *) type. N ⁺ wherein R 'is hydrogen or alkyl of 2 to 6 carbon atoms. The process for the preparation of these water-soluble polyester resins consists in esterifying 95 to 780 wt.% At 180 to 250 ° C in nitrogen or CO 2 or using azeotropic solvents of the toluene, xylene or ethylbenzene group. parts by weight of trivalent to trivalent alcohols having from 2 to 28 carbon atoms from 220 to 820 wt. parts of carboxylic acid compounds of the group of benzenedicarbonic acids, ¢ (-unsaturated acyclic acids having 4 to 5 carbon atoms or polymeric carboxylic acids having a molecular weight of not more than 1 500 »or with their functional derivatives) 60 to 900 parts by weight of salts derived from benzenesulfodicarboxylic acids, sulfosuccinic or sulfoalkylsuccinic acids, or sulfoacid salts derived from polymeric carboxylic acids, and the reaction is terminated at an acid number of 15 to 60 mg KOH / g.

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239 971

The polyester resins prepared according to the present invention are characterized by very good water solubility, unlimited water dilutability, good storage stability, no volatile and hygienically harmful organic components.

For the preparation of the water-soluble polyester resins according to the invention, 2 to 3 strong alcohols, in particular ethylene glycol and its homologues of up to 600, propylene glycol and its homologues of up to 600, polyethylene glycol or polypropylene glycol of up to 600, containing up to 10 % wt. branching components such as trimethylolpropane or trimethylolethane, 2,4-dimethyl-2-ethylhexane-1,3-diol, 2,2-dimethyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol ,

1,5-pentanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, trimethylolpropane, trimethylolethane, glycerol. As dibasic carboxylic acids, in particular, o-phthalic acid, isophthalic acid, terephthalic acid or derivatives thereof, fumaric acid, maleic anhydride, citraconic and mesaconic acid, 1,3-cyclopentanedicarboxylic acid, ₄ 1,2-cyclohexanedicarboxylic acid and the like can be used. In particular, the potassium and salt salts of sulfosuccinic and sulfoisophthalic acids can be used. The components may be used alone or in admixture with each other, but some derivatives, such as esters of the acids mentioned, may also be used.

The preparation may be carried out in a one-step process, while the use of volatile components is more advantageous in a multi-step process. The secondary reactants, most often water or methanol, must be efficiently removed from the reaction mixture by an inert gas stream or by means of solvents forming an azeotropic mixture. The reaction temperatures range from 180 to 250 ° C.

The sulfonyl derivatives of the carboxylic acids mentioned in the present invention can be introduced into the reaction mixture as preformed raw materials, or in some cases it is preferable to prepare them in situ. Thus, for example, it is possible to add to the esterified maleic acid or fumaric acid HaHSO4 or NagSgO4 to form a polymeric structure.

The resulting products are low viscous melts; or solids which may be dissolved, preferably at elevated temperature, in water, preferably demineralized or distilled. However, non-potable water can also be used, although using water of high hardness may, in some cases, cause haze or even precipitate.

Aqueous resin solutions can be used for the purposes mentioned above. After evaporation of water they form a hard and flexible film, which can be used both in the field of paints and for many other technical purposes, especially where it is necessary to strengthen the surface and improve the mechanical properties. The resin or composition containing them can be used for temporary treatment as long as their solubility is maintained. However, they can be converted into an insoluble form by the addition of some electrolytes (eg aluminum salts), thereby providing a permanent treatment.

The composition of the water-soluble polyester resins and the process for their preparation are exemplified by the following examples.

The specifications of the polymeric acids used in the examples are given in the following table.

239 971

Polymer specifications. of the acids listed in Examples 1-5

Polymeric acid Λ (B) C D Molecular weight 800 935 600 500 Acid number (mg KOH / g) 70 120 91.6 210 (-COOH content, % by weight ·) (5.6) (9.6) (7.3) (16.8) Acrylic acid content in monomer mixture (% by weight) 9 · » 27 Mar: Number of -COOH groups per 1 mol 1 2 1 7.5 Representation of maleic anhydride in monomer mixture hm ·) 10.5 8 «Μ Sulfo groups in polymeric acid (% by weight -SO ₃ Ua ⁺ ) · 15 Dec Other monomers involved in the formation of £ - styrene, ethyl- styrene, indene, 1 , 4-bu- 2-ethyl- hexylacry- specific (carboxylic) acids acrylate, methyl- acrylate, butyl- acrylate tadien substances, styrene, methyl methacrylate

Example 1 239 971

Water-soluble polyester resin containing 79 wt. ester-linked polyethylene glycol moieties with mol. weight 600, 2 wt. % ester-linked glycerol residues, 18 wt. % ester-linked isophthalic acid residues and 1 wt. ester-linked residues of the mono-sodium salt of isophthalic acid.

This polyester resin is prepared in a one-step process by reacting 100 wt .-% at 180 DEG-240 DEG C. under a nitrogen atmosphere. isophthalic cyaneline with a mixture of 337.7 wt. parts by weight of polyethylene glycol with a molecular weight of 600 and 6.9 wt. parts of glycerol. The reaction is terminated when the acid number reaches not more than 16 mg KOH / g by cooling to 100 to 120 ° C. 182 wt. parts of water are added and the solution is mixed at 50 ° C with sodium hydroxide solution prepared by dissolving 2.4 wt. % NaOH in 7.2 wt. water. Dilute 808 wt. parts by weight of water to a dry matter solution of 30 wt.

The resulting solution is practically clear when using distilled or demineralized water. When using water, the utility solution exhibits opalescence, the intensity of which increases with the hardness of the water.

Example 2

Water-soluble polyester resin containing 49 wt. % of ester-linked triethylene glycol residues; % ester-linked trimethylolpropane residues, wt. % ester-linked isophthalic acid residues, wt. % ester-bound terephthalic acid residues, wt. % ester-linked polymeric acid B residues and 7 wt. ester-linked 5-sulfoisophthalic acid monosodium salt.

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This polyester resin is prepared by a one-step synthesis by introducing a 783 wt. parts of triethylene glycol and 30 wt. parts of trimethylolpropane and 714.9 wt. % of isophthalic acid, 37.6 wt. % of terephthalic acid, 65.1 wt. % of polymeric acid B; and 117.2 wt. % of the monosodium salt of 5-sulfoisophthalic acid. In a nitrogen or carbon dioxide atmosphere, the mixture is esterified at 190 to 230 ° C to distill off the reaction water. When the acid number falls below 18 mg KOH / g, a minimum of 170 wt. parts of water of reaction, the reaction is stopped by cooling to 180 ° C and ^product $ ypustí cooling belt.

The softening point of the polyester resin as determined by the ring-ball method is 85 to 90 ° C, the bound sulfur content is

1.8% by weight ·

Example 3

Water - soluble polyester resin containing

9.8 wt. % ester-linked 1,2-cyclohexanediol residues, wt. % ester-linked polyethylene glycol moieties having a molecular weight of 600, 0.1 wt. % ester-linked pentaerythritol residues, 71 wt. % of ester-linked residues of polymeric acid C containing 15 wt. % of -SO4a and 18 wt. ester-linked potassium salt of polymeric acid C.

This polyester resin is prepared in a one-step process. The work is carried out in such a way that to the mixture 109.4 wt. 1.2 parts by weight of 1,2-cyclohexanediol; % of pentaerythritol and 10.9 wt. 1000 parts by weight of polyethylene glycol of molecular weight 600, heated to a temperature of 100 to 120 [deg.] C., were added successively. The space above the reaction mixture is filled with nitrogen and with a constant supply of N? the reaction mixture was esterified at 150 to 210 C to ^D

239,971 acid number 20 mg KOH / g with continuous removal of esterification water. The reaction product is cooled to 100 to 120 ° C and dissolved under stirring with 733 wt. parts of distilled water to form a solution with a dry weight of 60 wt. The resulting solution was further cooled to 50 ° C and a solution was added

18.3 wt. % KOH in 100 wt. parts by water and further diluted by adding 1,775 wt. parts of distilled water to a solution containing 30 wt. non-volatile components.

The resulting solution is free of mechanical impurities. Its viscosity at 20 ° C is 20 to 40 mPa · s.

Example 4

Water-soluble polyester resin containing 17 wt. % ester-linked 1,4-cyclohexanediraethanol residues, 72 wt. % ester-linked polymeric acid A residues, 1 wt. % ester bound fumaric acid residues and 10 wt. ester-linked sulfosuccinic acid residues.

Said polyester resin is prepared in a two-step process such that 1584 wt. parts of 1,4-cyclohexanedimethanol, 575 wt. parts of maleic anhydride and 6,612 wt. A portion of polymeric acid A added to the reaction mixture as a 60% xylene solution is prepared by a polyester resin containing ethylenically unsaturated bonds in the chain. The esterification of the reactants takes place at a temperature of 150 to 220 ° C, the esterification water is removed from the reaction mixture by azeotropic distillation using xylene introduced by polymeric acid A. The reaction is led to an acid number of 20 mg KOH / g. The xylene contained is distilled off, the resulting product is cooled to 100 DEG C. and dissolved in 500 wt. parts of ethylene glycol monoethyl ether or ethylene glycol monoacetate. The solution is diluted with 500 wt. parts distilled vo9

239 971 dy. In the second step, NaHSO4 is added to the unsaturated polyester bonds. The temperature of the solution was raised to 90-95 ° C and a solution of 519 wt. % NaHSO4 in 3,000 wt. during the reaction, the reaction mixture is further diluted with 5,000 wt. parts of water · The reaction is terminated by cooling the product to 30 ° C when the reaction to HSO ions is negative. The resulting solution is diluted to a concentration of 20% by weight. % of non-volatile components by addition of 27 300 wt. water parts ·

The resulting solution is light yellow in color and does not contain mechanical impurities · Its viscosity at 20 ° C is 25 to 40 mPa.So

Example 5

Water-soluble polyester resin containing 20 wt. % of ester-linked triethylene glycol residues; % ester-linked glycerol residues, 59.3 wt. % ester-linked polymeric acid D residues, 16.8 wt. ester-linked residues of the sodium salt of polymeric acid D and 1.9% by weight · ester-linked residues of the triethanolammonium salt of polymeric acid D ·

The aforesaid water-soluble polyester resin is prepared in a one-step process by adding 1360 wt. parts of triethylene glycol and 150 wt. parts of glycerol and to this mixture is added 5,330 wt. parts of polymeric acid D in the form of a xylene solution containing 60% by weight of non-volatile components. The mixture is esterified at 180-235 ° C, the esterification water is removed from the reaction system in the form of an azeotropic mixture with xylene, with the major part of the xylene contained being distilled off before starting the esterification to obtain the desired reaction temperature. After reaching an acid number of 50 mg KOH / g, the remaining xylene is distilled off from the reaction mixture and the reaction product

The temperature of the resulting solution is adjusted to 45 ° C, and then a solution of 173 parts by weight of NaOH in 1000 parts by weight of water and a solution of 72 parts by weight are gradually added. parts of triethanolamine in 500 wt. · After homogenization with the addition of 13,000 wt. parts of water adjusts the content of non-volatile components in the solution to 25% by weight ·

The resulting product is a light liquid free of mechanical impurities. Its viscosity at 20 ° C is 30 to 50 mPa · s. With distilled water to clear blends perfectly roz4,4toky, the presence of Ca ions in an amount corresponding to 20 to 30 ⁰ therein. hardness induces poor opalescence.

Claims (2)

SUBJECT OF THE INVENTION 239 971 1. Water-soluble polyester resins based on condensation products of polyhydric carboxylic acids with two- or three-molar alcohols or functional derivatives of these components, containing from 8 to 83% by weight of ester-linked residues of two- to three-carbon alcohols having from 2 to 28 carbon atoms % by weight of ester-bound residues of the compounds of the general formula R - (COO) -, - (00C) - R - (C00-M ⁺ ) and optionally up to 15% by weight of the ester-linked residues of the compounds of the general formula, - (00C) _x - R - SO ₃ 'M ⁺ or - (000) _x - R - (COO-M ⁺ ) _y , where R is a residue of benzenedicarboxylic acids, OC, --unsaturated acyclic carboxylic acids containing 2 to 4 carbon atoms or polymeric carboxylic acids with a maximum molecular weight of 1 500, x being 1-8, y is 1-7, and M is sodium, potassium or an alkylamino group (R *) 4 N ⁺ , where R * is hydrogen or alkyl of 2 to 6 carbon atoms. 2. A process for the preparation of the water-soluble polyester resins according to item 1 by condensation of polyhydric carboxylic acids with two- or three-mono-alcohols or functional derivatives of these components, characterized in that at 180 to 250 ° C in nitrogen or carbon dioxide or azeotropic Solvents from 239 971 of the toluene, xylene or ethylbenzene group esterifies 95 to 780 wt. parts by weight of divalent and trivalent alcohols having from 2 to 28 carbon atoms from 220 to 820 wt. % of carboxylic acid compounds of the group of benzenedicarboxylic acids, saturated acyclic acids having 4 to 5 carbon atoms or polymeric carboxylic acids having a molecular weight of not more than 1 500 or a functional derivative thereof and optionally 60 to 900 wt. parts of benzenesulfodicarboxylic acid salts, sulfosuccinic acid or sulfoalkylsuccinic acid, or sulfonic acid salts derived from polymeric carboxylic acids, and the reaction is terminated to an acid number of 15 to 60 mg KOH / g.