KR100369738B1 - Process for producing polyester resin easily dyeable in dispersion dye - Google Patents

Abstract

PURPOSE: Provided is a process for producing a polyester resin for producing polyester fiber easily dyeable in a dispersion dye under the atmospheric pressure at a low temperature. CONSTITUTION: The polyester resin is produced by polymerizing ethylene glycol as a first diol component, terephthalic acid or ester thereof as a first acid component, less than 5wt%(based on the total polyester) of an ethylene oxide additive(formula I) of bisphenol-A as a second diol component, and less than 5wt%(based on the total polyester) of trimellitic anhydride or 1,3,5-tricarboxyl benzoic acid as a second acid component, wherein the total amount of the second diol component and the second acid component is 3-7wt%. In the formula, R is hydrogen or C1-C3 hydrocarbon and m and n are an integer of 2-30.

Description

Method for preparing Disperse Dye Dibasic Polyester Resin

The present invention relates to a method for producing a polyester, and more particularly to a method for producing a polyester resin for producing polyester fibers that can be easily dyed in a disperse dye at normal pressure and low temperature.

Polyesters such as polyethylene terephthalate have excellent physical and chemical properties and are excellent in heat resistance, and thus are widely used for clothing, film, and litter. However, polyester fiber does not have a reactor capable of bonding with dyes in its chemical structure, and because the physical structure is dense, the dye permeability is poor, so in case of other fibers, especially natural fiber, it is dispersed at normal pressure and low temperature (below 100 ° C). It is a flame retardant fiber which has not been dyed with dyes and has been dyed under high pressure and high temperature conditions.

Conventionally, a method of dyeing a flame retardant polyester fiber under normal pressure by adding a chelating agent called a carrier to a dye bath or printing arc is known. However, such a carrier dyeing method has a problem that the carrier is a harmful substance, so that the working environment of the dyeing plant is poor and the drainage is difficult, as well as a lot of dyeing defects such as dyeing spots occur.

There is also a method of modifying the polyester as another method for improving the flame retardancy of the polyester. This reforming method is mainly the method of using isophthalic acid and sodium sulfoisophthalic acid as a copolymerization component (second component) and polyalkylene glycol as a component (Japanese Patent Application Laid-Open No. 58-136821 and Japanese Patent Application Laid-Open. 61-6887). However, this method requires a separate additional step in the spinning and stretching process when the content of the second components is less than 7% by weight based on the total polyester, and when the content of the second component exceeds 7% by weight, the mechanical properties and operability of the fiber are poor. It was a disadvantage.

In the study for improving the problems of the prior art as described above, the inventors of the present invention are not only capable of normal-pressure dyeing of polyester for fabric production using a specific copolymer component in an amount of 7% by weight or less, but additionally added in spinning and stretching processes. The surprising fact that the process is not required and the mechanical properties and the operability of the fiber is excellent, and based on this fact, the present invention has been completed.

Therefore, according to the present invention, ethylene glycol as the first diol component, terephthalic acid or its ester as the first acid component, and an ethylene oxide adduct of bisphenol-A represented by the following general formula (I) as the second diol component, Provided is a method for producing a disperse dye dibasic polyester, characterized in that polymerization is carried out by addition of trimellitic anhydride or 1,3,5-tricarboxyl benzoic acid as a diacid component.

(Wherein R is hydrogen or a hydrocarbon group of 1 to 3 carbon atoms, m and n are integers of 2 to 30)

Hereinafter, the present invention will be described in more detail.

In the present invention, the ethylene oxide adduct (I) of bisphenol-A which is the second diol component, even when used in a small amount, the methylene group of bisphenol-A can sufficiently destroy the dense structure of the polyester, and the ether connected thereto. Bonding is excellent in water absorption at the time of dyeing, the prepared polyester has a structure that can penetrate the dispersion dye well even under normal pressure, low temperature conditions. In the present production method, the content of ethylene oxide adduct (I) of bisphenol-A to the total polyester is preferably 5% by weight or less, because the content of ethylene oxide adduct (I) of bisphenol-A is 5% by weight. This is because when the percentage is exceeded, the crystallinity of the polyester is so broken that the mechanical performance of the fiber is poor. On the other hand, the number of ether bonds (m, n) in the ethylene oxide adduct (I) of bisphenol-A is also important. The larger the number of m and n, the higher the dyeability of the polyester in the disperse dye. However, if it exceeds 30, the reactivity decreases and the polyester molecular chains fail to bond and fall off in the later process. (易 染 性) The effect can not be planned. On the other hand, when m and n are less than 2, the number of ether bonds is small, so that the water absorption ability is poor, and eventually, the effect of improving the dye resistance cannot be expected.

In this production method, trimellitic anhydride or 1,3,5-tricarboxyl benzoic acid is used as the second acid component. This second acid component has three functional groups, and since the reactivity of the two functional groups is higher than that of the other functional groups, that is, the reaction rate is fast, the other functionalities with low reaction rates The genital groups remain in an almost unreacted state without participating in polymerization, and thus the remaining unreacted functional groups have an effect of enhancing water absorption capacity and dyeing speed. In the present invention, the content of the second acid component is limited to 5% by weight, more preferably 5% by weight or less, based on the total polyester, which is excessively increased in melt viscosity during polymerization of the polyester when used in excess of 5% by weight. This is because it tends to be difficult to produce a polyester having a desired molecular weight level, which in turn can lower the mechanical properties of the fiber.

In addition, according to the present invention, the sum (A + B) of the content (A) of the second diol component and the content (B) of the second acid component is limited to 3 to 7% by weight or less, which exceeds 7% by weight. If the content of the copolymer component is too much, the problem in the prior art as described above is reproduced as it is, if less than 3% by weight because the dyeing speed is slow and the desired degree of dyeability improvement in the present invention can not be expected to be.

In the present invention, the second diol component of the second components may be added at any point before the completion of the ester reaction or transesterification reaction, the second acid component is preferably added in the initial stage of polymerization.

The polyester resin of the present invention as described above can be produced by spinning and stretching in a conventional manner to the fiber, the polyester fiber prepared as described above can be dyed with a disperse dye under normal pressure at 100 ℃ or less, in particular at 98 ℃ Since the general polyester is dyed at a high temperature of 130 ° C. or higher, the dyeability is equal to or higher than that, and thus, the fibers which are damaged at high temperature and high pressure, for example, acetate, wool, nylon, etc., can be used for teaching and mixing. In addition, the general atmospheric pressure dyeing machine can be used in the dyeing facility, so that the limitation of the facility is eliminated, and the fuel cost and power cost required for high temperature and high pressure can be reduced.

Features and other advantages of the invention as described above will become more apparent from the description of the non-limiting examples described below.

On the other hand, the dyeing resistance, light fastness and heat shrinkage rate evaluated in Examples and Comparative Examples to be described later are performed by the following method.

★ Dyeing property: Pore was dyed for 60 minutes at 98 ° C. using Poron Navy Blue RD-RLS disperse dye. UV absorbance was measured at 607.0 nm for measurement. For reference, the dyeability of the unmodified polyethylene terephthalate with the same dye at 130 ° C. under pressure was 80.1%.

★ fastness of light fastness: The dyeing pores obtained in the measurement of dyeability were treated in a weather resistance tester at a temperature of 63 ° C. using a carbon arc light source.

Grade 1 ‥‥‥ Discoloration when treated for 1 to 5 hours

Grade 2 ‥‥‥ Discoloration when treated for 5 to 10 hours

Grade 3 ‥‥‥ Discoloration after 10-20 hours treatment

Grade 4 ‥‥‥ Discoloration after 20-40 hours treatment

Grade 5 ‥‥‥ Discoloration after 40 to 80 hours of treatment

★ heat shrinkage: After immersing the yarn in boiling water at 100 ℃ for 30 minutes, the length before and after treatment was measured and calculated from the following equation.

Example 1

Nitrogen atmosphere was added to 100 kg of dimethyl terephthalate and 570 kg of ethylene glycol by adding 30 kg (about 3 wt%) of bisphenol-A ethylene oxide adduct (m = 28, n = 25, R = H) and 250 g of zinc acetate. The resulting methanol was continuously discharged out of the system while raising the temperature at 150 to 240 ° C. for 4 hours under a transesterification reaction.

When the theoretical amount of methanol spilled, 10 kg of trimellitic anhydride (about 1% by weight), 100 g of phosphoric acid and 350 g of antimony trioxide were added, stirred for about 5 minutes, and then transferred to the polymerization reactor. In the polymerization reactor, the pressure was gradually reduced, the temperature was raised to 285 ° C, and polymerization was performed until the target degree of polymerization (I.V. = 0.670) was reached. When the reaction is complete, the vacuum is broken with nitrogen and immediately made into chips.

The obtained chip was dried according to a conventional method and spun at a speed of 135 m / min in a spinning machine to prepare an unstretched yarn, which was stretched about 3.017 times to prepare 75 d / 36f of fiber. The strength, elongation, shrinkage, dyeing and light fastness of the fibers produced are shown in Table 1 below.

[Examples 2-3 and Comparative Examples 1-2]

The same procedure as in Example 1 was repeated except that the content of the second component was changed as shown in Table 1 below.

Example 4

The same procedure as in Example 1 was repeated except that 1,3,5-tricarboxylbenzoic acid was used in an amount as shown in Table 1 as the second acid component.

[Examples 5 to 6 and Comparative Examples 3 to 4]

The same procedure as in Example 1 was repeated except that the n and m values of the ethylene oxide adduct (I) of bisphenol-A were changed as shown in Table 2 below. The strength, elongation, shrinkage, dyeing and light fastness of the fibers produced are shown in Table 2 below.

Claims (2)

Ethylene glycol as the first diol component, terephthalic acid or its ester as the first acid component, ethylene oxide adduct of bisphenol-A represented by the following general formula (I) as the second diol component, and as the second acid component A method for producing a disperse dye dibasic polyester, characterized by polymerizing by adding meritic anhydride or 1,3,5-tricarboxyl benzoic acid. (Wherein R is hydrogen or a hydrocarbon group of 1 to 3 carbon atoms, m and n are integers of 2 to 30) The addition amount (A) of the 2nd diol component and the addition amount (B) of a 2nd acid component are respectively 5 weight% or less with respect to all polyester, The addition amount (A) of a 2nd diol component, and 2nd The sum (A + B) of the addition amount (B) of an acid component is 3 to 7 weight%, The manufacturing method of the disperse dye dibasic polyester characterized by the above-mentioned.