KR100373884B1 - A process of preparing for water dispersive polyester resin - Google Patents

Abstract

The present invention relates to a method for producing a water-dispersible polyester resin, comprising a polyester resin, an aromatic difunctional carboxylic acid compound, a difunctional alcohol compound, and -SO ₃ M (M is a hydrogen atom or an alkali metal atom) functional group. After introducing the aromatic difunctional carboxylic acid compound having into the reactor, it is characterized in that the partial depolymerization reaction, transesterification reaction and polycondensation reaction so that the intrinsic viscosity is 0.49 ~ 0.52 at 200 ~ 285 ℃. The present invention can use a recycled polyester resin as the main raw material of the water-dispersible polyester resin is low production cost and is advantageous for environmental protection. In addition, the water-dispersible polyester of the present invention is excellent in adhesive strength with the polyester yarn, good flexibility and strength is useful as a slant for sizing in the weaving preparation process of synthetic fiber fabrics.

Description

Process for preparing water dispersible polyester resin {A process of preparing for water dispersive polyester resin}

The present invention relates to a method for producing a water-soluble polyester resin having good adhesion to paper and fibers, and particularly useful as a sizing for warping in a weaving preparation process of synthetic fiber fabrics.

In general, when weaving fabrics with synthetic fiber yarns, a sizing process is applied to the warp yarns in preparation before weaving to prevent the warp from being cut due to friction between the loom and the yarns during weaving. Will go through.

Until now, as a sizing sizing agent, water-soluble acrylic resins, partially ignited polyvinyl alcohol resins, etc. have been mainly used, but these have problems of weak adhesive strength with synthetic fibers, especially polyester yarns, and lack of flexibility and adhesive strength. As a result, the amount of use of the coating agent increased, the manufacturing cost increased, and the weaving operation rate and the fabric passing rate decreased due to the poor contact. Particularly, in the case of the conventional foils, there was a hassle to use for the jet jet loom, air jet loom, repier loom, shuttle loom according to their manufacturing process.

The present invention is to produce a water-dispersible polyester resin that can solve such conventional problems when used as a sizing for the sizing.

Conventionally, US Pat. Nos. 3,546,008, 3,853,820, 4,156,073 and the like are known as techniques for producing a water dispersible polyester resin. These patents include (i) polycondensation of polyester resins by reacting acid components selected from terephthalic acid or its ester-forming derivatives, isophthalic acid or its ester-forming derivatives and (ii) glycol components such as ethylene glycol and diethylene glycol. In order to impart water solubility or water dispersibility to a polyester resin, a method of adding an aromatic compound having a -SO ₃ M (M is a hydrogen atom or an alkali metal) functional group is described. These prior arts are all methods of producing water dispersible polyester resins from monomers.

On the contrary, an object of the present invention is to provide a method of using a regenerated polyester resin as a main raw material of a water dispersible polyester resin, thereby solving the problem of environmental pollution and at the same time manufacturing a water dispersible polyester resin at a lower cost. For reference, the discarded polyester resin is not semi-permanently decomposed and remains in nature, or incineration causes harmful gas to seriously pollute the environment.

The present invention is to provide a method for producing a water-dispersible polyester resin useful as an inclined sizing to use a recycled polyester resin as a main raw material to excellent adhesion and flexibility with synthetic fiber yarn.

Method for producing a water-dispersible polyester of the present invention for achieving such a problem is a polyester resin of the general formula (I) below, an aromatic difunctional carboxylic acid compound of the general formula (II) below, the general formula (III) Aromatic difunctional carboxylic acid compound of the general formula (IV) below having a difunctional alcohol compound and -SO ₃ M (M is a hydrogen atom or an alkali metal atom) functional group in the reactor, and then these are 200 ~ Partial depolymerization reaction, transesterification reaction and polycondensation reaction are characterized in that the intrinsic viscosity is 0.49 ~ 0.52 at 285 ° C.

In formulas (I) to (IV), R represents a benzene ring ( ), N is an integer of 1 to 200, R ₁ is a hydrogen atom or an alkyl group of 1 to 3 carbon atoms, R ₂ is CH ₂ CH ₂ -O-CH ₂ CH ₂ or an alkylene group of 2 to 8 carbon atoms, M is a hydrogen atom or an alkali metal atom.

Hereinafter, the present invention will be described in detail.

The present invention, after the regenerated polyester resin of the general formula (I) and the monomers of the general formula (II) to formula (VI) as the main raw material into the reactor, these are intrinsic viscosity 0.49 ~ 0.52 at 200 ~ 285 ℃ Partial depolymerization, transesterification and polycondensation reactions are performed. One or more reactors are used for the reaction, and partial depolymerization, transesterification and polycondensation are carried out simultaneously or sequentially. It is more preferable that the partial depolymerization reaction and the transesterification reaction are carried out at the same time and the polycondensation reaction is carried out later in consideration of the intrinsic viscosity of the reactants.

The polyester resin of the general formula (I), which is the main raw material, uses a regenerated polyester resin in which at least 90% of the repeating units are made of ethylene terephthalate. The molecular weight of the regenerated polyester resin is 400 to 40,000, more preferably 15,000 to 25,000. The amount of the recycled polyester resin is preferably 10 to 70% by weight based on the total weight of the reactants.

In addition, examples of the aromatic difunctional carboxylic acid compound of the general formula (II) used as a raw material for depolymerization and exchange reaction include dimethyl terephthalate, ester forming derivatives of dimethyl terephthalate, dimethyl isophthalate and dimethyl isophthalate. One or two or more compounds selected from the group consisting of derivatives are used. More preferably, isophthalic acid (dimethylisophthalate) and derivatives thereof are preferably used. Their amount is 10 to 40% by weight, more preferably 10 to 15% by weight relative to the total weight of the reactants.

As the bifunctional alcohol compound of the general formula (III), one or two or more compounds selected from the group consisting of ethylene glycol, diethylene glycol and 1,4-butanediol are used. More preferably, it is preferable to use diethylene glycol or 1,4-butanediol. Their amount is 10 to 30% by weight, more preferably 10 to 15% by weight relative to the total weight of the reactants.

Examples of the aromatic difunctional carboxylic acid compound of the general formula (IV) to impart water dispersibility to the resin include 5-sodiumsulfodimethylisophthalate, 4-sodiumsulfodimethylisophthalate, 5-sodiumsulfodimethylterephthalate or the like. Alkali metal salts are used. More preferably, 5-sodiumsulfodimethylisophthalate is used. Their amount is preferably 1 to 20% by weight relative to the total weight of the reactants, and more preferably 6 to 12% by weight.

The above components are mixed and subjected to partial depolymerization and exchange reaction under a non-catalytic reaction or by removing the reaction by-products under normal pressure using tetrabutyltatinatc, zinc acetate or the like as a catalyst. In some cases, when decomposition or depolymerization occurs excessively and the intrinsic viscosity is too low, a water-dispersible polyester resin having desired physical properties may be obtained by inducing a vacuum state in the reaction tube and polycondensing again.

The reaction temperature is preferably 200 to 285 ° C, and it is important to maintain the intrinsic viscosity of the water-dispersible polyester resin at 0.49 to 0.52. When the intrinsic viscosity is less than the above range, the adhesive strength may be lowered, and when the intrinsic viscosity exceeds the above range, the water dispersibility may be lowered.

The water-dispersible polyester resin of the present invention thus prepared is placed in water, heated and stirred to form the above resin dispersion, and used as an inclination sizing agent. When the water-dispersible polyester resin of the present invention is used as an inclination sizing agent, it is subjected to a process of water dispersion, adhesion solidification, and melt water dispersion, so that there is no weaving trouble caused by woven water, so that it can be used universally without distinction of types of loom Can be. In addition, since the water-dispersible polyester resin of the present invention uses a regenerated polyester resin as a main raw material, it is inexpensive and can also prevent environmental pollution.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited only to the following examples.

Example 1

850.0 g of the collected recycled polyester resin is added to the polymerization reactor, 190.0 g of dimethyl isophthalate and 220.0 g of diethylene glycol are added, and 120.0 g of 5-sodium sulfodimethyl isophthalate is added thereto. 0.40 g of tetrabutyl titanate was used as a catalyst and 0.15 g of trimethyl phosphate was added as an antioxidant. The reactor is then subjected to partial depolymerization and exchange at the same time as 250 ℃, and the reaction product is collected intermittently to control the polycondensation reaction while adjusting the vacuum so that the intrinsic viscosity of the resin (orthochlorophenol at 30 ℃) is 0.51. A water dispersible polyester resin was prepared. The resin obtained here was introduced into a pure water (20% by weight), and then heated and stirred to prepare a resin dispersion composition, which was used as an inclined arc favoring agent. At this time, weaving utilization rate was very good, 97%.

Example 2

425.0 g of dimethyl terephthalate and 190.0 g of dimethyl isophthalate were added to the polymerization reactor, 135.0 g of ethylene glycol and 220.0 g of diethylene glycol were added, and 120.0 g of 5-sodium sulfodimethyl isophthalate was added thereto. 0.40 g of tetrabutyl titanate was used as a catalyst, and 0.10 g of trimethyl phosphate was added as an antioxidant. Next, the reaction was performed while raising the temperature of the reactor to 220 ° C., and by-products were removed to prepare 450 g of a polyester polymer. 425.0 g of recycled polyester resin continuously collected, 0.40 g of tetrabutyl titanate, and 0.10 g of trimethyl phosphate were further added to the polymerization reactor, and then the partial depolymerization and exchange reaction were simultaneously performed while controlling the temperature inside the reactor to 270 ° C. By removing the reaction by-products and intermittently taking the reaction product, the polycondensation reaction was carried out while controlling the vacuum so that the intrinsic viscosity of the resin (orthocrorophenol at 30 ° C.) was 0.52, thereby preparing a desired water-dispersible resin. The resin obtained here was introduced into a pure water (20% by weight) and then heated and stirred to prepare a resin dispersion composition, which was used as an inclined arc favoring agent. At this time, weaving utilization rate was very good at 91%.

Example 3 to Example 6 and Comparative Example 1 to Comparative Example 2

The same process and conditions as in Example 1 were used except that the amount of the polyester resin as the main raw material, the type and amount of the acid and glycol components as monomers, and the intrinsic viscosity of the water-dispersible polyester resin prepared were changed as shown in Table 1. An acidic polyester resin and a resin dispersion composition thereof were prepared and used as an inclination arcing agent. The results of measuring the weaving utilization rate are shown in Table 2.

Polymerization Condition (Unit: g) division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Main raw material Recycled Polyester 850 425 210 400 850 850 850 850 General Polyester 0 450 0 0 0 0 0 0 Monomer Acid Component Dimethyl terephthalate 0 425 640 0 0 0 0 0 Dimethylisophthalate 190 190 190 190 190 190 380 380 DMIS 120 120 120 120 120 120 120 120 Monomer glycol component Ethylene glycol 0 135 195 0 0 0 100 100 Diethylene glycol 220 220 220 220 0 120 440 440 1,4-butanediol 0 0 0 0 210 100 0 0 Intrinsic viscosity (㎗ / g) 0.51 0.50 0.51 0.51 0.52 0.50 0.49 0.44

※ In Table 1, DMIS is 5-sodiumsulfodimethylisophthalate.

Weaving utilization rate division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Weaving utilization rate (%) 97 91 93 90 95 93 77 60

The present invention uses a recycled polyester resin as the main raw material is low manufacturing cost and can solve the environmental pollution problem. In addition, the water-soluble polyester resin prepared by the present invention can improve the weaving efficiency and the fabric passing rate when used as an inclined sizing for excellent adhesion and flexibility with paper, fibers.

Claims (6)

Regenerated polyester resin of the general formula (I) below, wherein at least 90% of the repeating units are made of ethylene terephthalate, aromatic difunctional carboxylic acid compound of the general formula (II) below, difunctional alcohol of the general formula (III) below After the compound and -SO ₃ M (M is a hydrogen atom or an alkali metal atom) functional group, the aromatic difunctional carboxylic acid compound of the following general formula (IV) is introduced into the reactor, and these are intrinsic viscosity at 200 ~ 285 ℃ A method for producing a water-dispersible polyester, characterized in that it is subjected to partial depolymerization reaction, transesterification reaction and polycondensation reaction so as to be 0.49 to 0.52. In formulas (I) to (IV), R represents a benzene ring ( ), N is an integer of 1 to 200, R ₁ is a hydrogen atom or an alkyl group of 1 to 3 carbon atoms, R ₂ is CH ₂ CH ₂ -O-CH ₂ CH ₂ or an alkylene group of 2 to 8 carbon atoms, M is a hydrogen atom or an alkali metal atom. The process for producing a water dispersible polyester according to claim 1, wherein the partial depolymerization, transesterification and polycondensation are carried out simultaneously or sequentially in the reactor. delete The aromatic difunctional carboxylic acid compound according to claim 1, wherein the aromatic difunctional carboxylic acid compound is one selected from the group consisting of dimethyl terephthalate, ester forming derivatives of dimethyl terephthalate, dimethyl isophthalate and ester forming derivatives of dimethyl isophthalate. Or two or more compounds. The water-dispersible polyester according to claim 1, wherein the difunctional alcohol compound of the general formula (III) is one or two or more compounds selected from the group consisting of ethylene glycol, diethylene glycol and 1,4-butanediol. Manufacturing method. The process for producing a water-dispersible polyester according to claim 1, wherein the aromatic difunctional carboxylic acid compound of formula (IV) is 5-sodiumsulfodimethylisophthalate.