KR100531041B1 - Easily dyeable copolyester polymer prepared by terephthalic acid process, Fibers thereof and Method for preparing the same - Google Patents

Abstract

The present invention relates to an easy-to-dye polyester polymer produced by a polyester polymerization method using terephthalic acid as a main polymerization polymer and a method for producing the same. Specifically, the glass transition temperature (Tg) is an absolute temperature of 330 ~ 350K, the melting temperature (Tm) of 510 ~ 525K, the copolyester polymer and the ratio of Tm and Tg satisfies 1.51 ≤ Tm / Tg ≤ 1.55 and its It relates to a production method, and more specifically, to the intrinsic viscosity produced by the terephthalic acid method with terephthalic acid copolymerized from 1 to 10% by weight of polyalkylene glycol ethers having a number average molecular weight of 200 to 2,000 as the main raw material, 0.6 to 0.7dl / g It relates to a polymer easily phosphorus dyeing and a method for producing the same.

Easily dyed polymers prepared by the present invention have the same physical properties as conventional polyethylene terephthalate fibers and show excellent properties possible at lower temperatures than conventional polyethylene terephthalate fibers.

Description

Easy dyeable copolyester polymer prepared by terephthalic acid process, Fibers about and method for preparing the same}

The present invention relates to a copolyester polymer using the TPA method using a terephthalic acid (hereinafter abbreviated as TPA) as a raw material, a fiber thereof, and a method for producing the same. More specifically, in the TPA polymerization method using terephthalic acid as the main raw material, a polyalkylene glycol ether having a number average molecular weight of 200 to 2000 (hereinafter abbreviated as PAG) is copolymerized 1 to 10% by weight with respect to the polymer, and ether By adjusting the molar ratio of ethylene glycol and terephthalic acid to 1.05 ~ 1.51, by controlling the content of DEG generated during polymerization, the glass transition temperature (hereinafter abbreviated as Tg) and the melting temperature (Melting Temperature, It is to provide a copolyester polymer that satisfies the ratio 1.51 ≤ Tm / Tg ≤ 1.55 (where temperature is absolute temperature, Kelvin Temperature) and a method of manufacturing the same. As a result, the polymerized product according to the present invention maintains excellent elasticity and the like inherent in conventional polyethylene terephthalate (hereinafter abbreviated as PET), while determining the area of the amorphous portion that can be dyed with a disperse dye. When analyzed by (Heat of fusion, abbreviated as ΔHf), it is possible to dye at a temperature (about 100 ° C) below the dyeing temperature of PET fiber (usually 130 ° C) while being 67 to 87% of the conventional polyethylene terephthalate. Do.

      PET fiber is a polymer material that is widely used in clothing fibers, industrial fibers, films, etc., because of its excellent mechanical properties and excellent resistance to chemicals and the environment. However, in spite of its excellent properties, there is a problem in that dyeing by disperse dyes is possible only at a high temperature of about 130 ° C. due to the absence of a functional group that can be involved in dyeing when used as a garment fiber.

      This has a limitation in use that can not be used with fibers that damage when dyed at high temperature and high pressure conditions such as metallic yarn (natural yarn) or natural fibers.

The polymerization method of polyester can be divided into two types based on starting material. The first method is to use TPA as a raw material. Currently, the majority of the polyester industry adopts a direct ester reaction of TPA and ethylene glycol (abbreviated as EG) and bishydroxy ethyl terephthalate (hereinafter abbreviated as BHET) and these. It is a method of preparing a low degree of polymerization oligomer of polycondensation under high vacuum. Next, there is a method using DMT (dimethyl terephthalate) as a raw material. In this method, bishydroxy ethyl terephthalate and their low-polymerization oligomers are prepared by transesterification of DMT and EG in the presence of a catalyst and then polycondensed under high vacuum. In terms of production cost and productivity, TPA polymerization is widely used, and DMT polymerization has high production cost and low productivity by equipment (typically, 17% more DMT is used than TPA to produce the same amount of polymer. Committed). In the DMT process, metal salts such as zinc acetate, manganese acetate, and magnesium acetate are used as catalysts for the transesterification reaction between DMT and EG. There is a problem in that a stabilizer should be added to have deactivation and UV light activity. However, the TPA method does not use a catalyst for the esterification reaction of TPA and EG, and also has the advantage that the activity of antimony trioxide, which is mainly used as a polycondensation catalyst, is small and does not require a separate stabilizer.

      In the present invention was used to copolymerize PAG having a molecular weight of 200 ~ 2000 for dyeing at low temperature, the technique using the PAG can be seen in the prior art belonging to the field of the invention, but the production method, molecular weight, the purpose of the invention, etc. You can see the difference. Japanese Patent No. 9-13229 is prepared by compounding 0.3 to 3% by weight of polyethylene glycol ether (hereinafter referred to as PEG) with 0.3 to 3% by weight of PEG having a molecular weight of 500 to 3,000. Here's how. This method utilizes the extraction of PEG to create long grooves in the fiber surface, but is not suitable for the purpose of the present invention without PEG extraction. Japanese Patent No. 58-120815 discloses a method of simultaneously injecting 5-sodium sulphonic acid dimethyl ester and PAG as a method for facilitating dyeing. The present invention has a different purpose because it is polyester fiber which is easy to dye in disperse dyes. In addition, it uses the DMT method, not the TPA method. In addition, US Pat. No. 6,218,007 describes a method for preparing fibers having a single yarn fineness of 1.2 to 2.25 dpf (denier per filament) using a polymer in which 0.5 to 4 wt% of PEG is added. The polymerization method proposed in the DMT method is different from the present invention. U.S. Patent 5,091,504 and U.S. Patent 4,975,233 disclose a method for preparing polyester fibers by adding 1.0 to 4.0% by weight of PEG having a molecular weight of 200 to 1,500. However, in the TPA method, diethylene glycol (hereinafter abbreviated as DEG) content of 1 wt% or less is essentially produced by side reactions, which lowers the thermal stability of the polymer, and thus the present invention tries to suppress it. U.S. Patents 5,091,504 and 4,975,233 rather seek to change properties by introducing DEG. When DEG is produced, the crystallinity of the polyester is lowered and the melting point is lowered, making it difficult to prepare a polymer having a range of 510 K ≤ Tm (absolute temperature) ≤ 525 K, which is the object of the present invention. In addition, US Pat. No. 4,211,678 proposes a method for preparing a copolyester that is easy to dye by adding 2 to 4 wt% PEG and 1 to 3 wt% dimer acid, which is complicated by the polymerization process. In addition to this, there is a disadvantage of increasing the production cost of the polymer.

      The technical problem to be achieved in the present invention is a polyester fiber that can be dyed at a temperature lower than the dyeing temperature of the conventional polyester fiber, while maintaining the inherent mechanical properties of the conventional polyester fiber using a low-cost manufacturing TPA method To preparing a copolyester polymer.

      That is, the TPA method copolymerizes 1-10% by weight of polypyrene ethylene glycol ether having a number average molecular weight of 200-2000 relative to the polymer, and adjusts the G value (molar ratio of ethylene glycol / terephthalic acid) to 1.05-1.15 to produce the polymer during polymerization. The present invention relates to a method for producing a copolyester polymer characterized by satisfying the physical properties of the ratio of the melting temperature (Tm) to the glass transition temperature (Tg) to the glass transition temperature (Tg) of 1.51 to 1.55. Another aspect of the invention is a polymer produced by the process and its fibers.

      The present invention for solving the above problems will be described in detail. The inventors have designed the molecular structure of copolyesters that are theoretically dyeable at low temperatures to achieve the present invention. The present inventors use aliphatic copolymer monomers which are not aromatic as copolymer monomers. Therefore, α, ω-diol, or polyethylene glycol ether (PEG), 1, 2 or more than 3 carbon atoms, such as 1, 3-propanediol (1, 3-propanediol), 1, 4-butanediol (1, 4-butanediol) Diol copolymer monomers such as 1, 3-polypropylene glycol ether, polyalkylene glycol ethers such as 1, 4-polybutylene glycol ether, and adipe Diacids such as adipic acid and succinic acid, their alkyl esters and acyl halides were selected.

      PAG was used to maintain the mechanical properties of conventional polyester levels and not to lower the melting point (528K) significantly. Copolymerization of α or ω-diol having 3 or more carbon atoms makes it difficult to crystallize the polyester, which leads to a large decrease in Tm.However, when aliphatic diacids or derivatives thereof are used, the decrease in Tm is 3 or more α, ω-diol. Because it is lower than the copolymer. In general, when the content of aromatic benzene, which exhibits large thermal properties of polyester, is low, the decrease in Tm is abrupt.

      In order to select the number average molecular weight of the selected PAG, the relationship between them and Tg and Tm was considered. In order to reduce Tm, a block copolymer must be formed, and to lower Tg, a random copolymer must be formed. However, if the formation of the block copolymer is too large, the segmented block copolymer (segmented block copolymer) becomes a polymer different from the physical properties of the conventional polyester. In consideration of this comprehensively, the molecular weight of PAG was set to 200 to 2,000. When the number average molecular weight is less than 200, the copolymer becomes a random copolymer (random copolymer), the Tm decrease is large, and when the number is larger than 2,000, the Tm decrease is not large, but Tg is hardly changed, which is not suitable for the purpose of the present invention.

      In addition, the content of PAG was 1 to 10% by weight (relative to the polymer). If it is less than 1% by weight, the amount is too small to have a copolymer effect. If it is greater than 10% by weight, the PET crystalline region dissolves in the amorphous region of the PAG regardless of the PAG molecular weight. Physical properties change badly.

      In addition, in the TPA polymerization method, unreacted TPA is insoluble and non-meltable, so that the oligomer filter or the polymer filter of the polymerizer is clogged or the pack pressure rises at the time of spinning. It is easy to produce the problem of deterioration. In order to minimize the amount of unreacted TPA, there is a method of increasing the esterification time or increasing the esterification temperature. However, increasing the esterification time or increasing the esterification temperature is not good because it increases the formation of side reaction product DEG, which impairs the thermal stability of the polymer. Therefore, it is desirable to suppress DEG production by lowering the G value (molar ratio of ethylene glycol and terephthalic acid) as much as possible. The value of G is preferably in the range of 1.05 to 1.15, and upon polymerization under these conditions, the content of DEG in the polymer is 0.7 to 1.5% by weight, and the glass transition temperature (Tg) of the object of the present invention is 330 to 350K, and the melting temperature ( Tm) is 510 ~ 525K and a copolyester polymer can be produced in which the ratio of Tm and Tg satisfies 1.51 ≦ Tm / Tg ≦ 1.55.

      As the polycondensation catalyst, a conventional polyester polycondensation catalyst can be used. Antimony-based catalysts such as antimony trioxide and antimony acetate, germanium-based catalysts such as germanium dioxide, and titanium-based catalysts such as tetrabutyl titanate and tetraisopropyl titanate can be used. Their content is preferably added to 0.01 to 5% by weight relative to the polymer.

      In addition, since the copolyester polymer according to the present invention is intended for fibers for clothing, it is possible to inject an anatase type titanium dioxide (anatase type) like conventional polyester. The amount is not added at all to super bright, depending on the purpose of the intended fiber, 200 to 500 ppm for the bright, 1000 to 5,000 ppm for the semi-dull, 10,000 to 40,000 ppm inputs are available for full-dull applications. In addition, in order to increase the specific gravity of the copolyester or to maintain transparency and improve the friction characteristics, barium sulfate or the like may be added in an amount of 5 wt% or less according to the purpose.

      Ether linkage of PEG has a problem that the binding energy (binding energy) is less susceptible to heat than the ester linkage of the polyester, but they are not weak to heat or light because they exist in a small dispersed phase in the PET matrix. However, in order to further increase their resistance to heat and light within the scope of not impairing the object of the present invention, phosphorus stabilizers such as trimethyl phosphate and triethyl phosphate, Irganox 1010, 1098, etc. Phenol (phenol) stabilizer, HLS (Hindered Amine Light Stabilizer) such as Iga Force 168 can be used in a range that does not impair the physical properties of the polymer without lowering the activity of the polymer polymerization catalyst.

      Hereinafter, terms and analysis methods to be used in Examples and the like will be described as follows.

1. IV: A solution mixed with 60/40 weight ratio of phenol and 1, 1, 2, 2-tetrachloroethane was measured at 30 ° C. using an Ubelode viscometer.

2. DEG content: The prepared polymer was hydrolyzed with monoethanol amine and analyzed by gas chromatography (GC, Gas Chromatography).

3. Melting temperature (Tm) and glass transition temperature (Tg): Using a DSC 7 of Perkin Elmer Inc. was heated to 10 ℃ / min and analyzed as a peak in the melting range.

4. Dyeability: circular yarns of the prepared yarns were dyed at 100 ° C with Kuralon Navy Blue, and visually judged to have good dyeing, and ○ stained levels were marked with × and color intensity of the dye was measured using a spectrophotometer. K / S maximum value was measured.

      Hereinafter, the present invention will be described in detail with reference to Examples. However, the scope of the present invention is not limited by this embodiment.

[Examples 1-5, Comparative Examples 1-3]

      Titanium dioxide content compared to the polymerization product, including 1270 kg of terephthalic acid and ethylene glycol having 30% titanium dioxide dispersed in an esterification reaction tank containing 1.3 tons of oligomer having an ester reaction rate of 96.0%, was measured. Slurry was prepared by stirring 620 kg of ethylene glycol (G value 1.13). The temperature of the ester reactor containing the oligomer was maintained at 260 ° C., and the slurry was added for 4 hours to drain the theoretical amount of effluent, followed by further stirring for 30 minutes, so that the esterification rate was in the range of 95.5 to 97.5%. It was. The amount of the oligomer, except 1.3 tons, was transferred to a polycondensation reactor, and PAG was added as shown in Table 1, followed by adding 300 ppm of antimony trioxide dissolved in 1% by weight of ethylene glycol to the polymer and starting to apply a vacuum. The temperature was raised to 290 ° C. The final vacuum was less than 0.1 Torr. When the load on the stirrer became equal to the load on normal polyester polymerization, the vacuum was broken with nitrogen and discharged with nitrogen. Polymer properties are shown in Table 1. 75d / 36f of the prepared polymer was prepared by spin drawing at 4,200 m / min at a spin temperature of 295 ° C., and the physical properties of the fiber are shown in Table 2.

division Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Comparative Example 3 PAG Type PEG PEG PEG PTMG PEG PEG PTMG    X PAG number average molecular weight 300 400 600 1,000 1,000 150 4,000    _ PAG content (% by weight) 4 4 4 4 6 4 4    X Glass transition temperature (K) 339.7 341.4 342.0 344.7 342.8 338.2 337.9 350.3 Melting temperature (K) 521.0 522.8 523.4 525.8 526.3 520.9 527.2 526.8 Tm / Tg 1.534 1.529 1.530 1.525 1.535 1.540 1.560 1.504 △ Hf 40.5 39.6 40.8 40.8 46.7 34.8 49.6 44.3 Titanium Dioxide (wt%) 0.3 0.03 0.3 0.3 0.03 0.3 0.3 0.3

PTMG: Poly 1,4-butylene glycol

division Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Comparative Example 3 Strength (g / d) 4.8 4.7 4.6 4.6 4.4 4.5 4.3 4.7 Elongation (%) 40 41 38 40 37 36 28 38 Dyeability O O O O O X X X K / S maximum value 19.3 18.2 18.0 17.5 19.0 8.3 6.5 3.0

* The higher K / S value, the darker the color of dyed paper.

The present invention relates to copolyester polymers and their preparation which can be concentrated in disperse dyes at lower temperatures than conventional PET while maintaining the inherent mechanical properties of conventional PET fibers using terephthalic acid as a raw material. By using the TPA polymerization method, it is possible to produce a copolyester polymer for polyester fibers having a low manufacturing cost and good dyeability.

Claims (6)

In the method for preparing a copolyester polymer using terephthalic acid (TPA) and ethylene glycol (EG), by adding 1 to 10% by weight of polyalkylene glycol ether having a number average molecular weight of 200 ~ 2,000 compared to the total composition A method of preparing a copolyester polymer by copolymerizing with oxy ethyl terephthalate (BHET) or an oligomer thereof and adjusting the G value (molar ratio of ethylene glycol / terephthalic acid) to 1.05 to 1.15. delete   The polyalkylene glycol ether (PAG) of claim 1 is a polyethylene glycol ether (PEG), 1,2-polypropylene glycol ether, 1,3-polypropylene glycol ether and 1,4-polybutylene glycol ether Method for producing a copolyester polymer, characterized in that selected from the group consisting of. delete    The glass transition temperature (Tg) produced by the method according to claim 1 is 330 ~ 350K in absolute temperature, the melting temperature (Tm) is 510 ~ 525K, the ratio of the melting temperature to the glass transition temperature (Tm / Tg) is Copolyester polymer, characterized in that 1.51 to 1.55.      Polyester fiber produced by spinning the polymer of the copolyester of claim 5.