KR930000116B1 - Preparation for polyethylene terephathalate copolymer - Google Patents

Abstract

The polyethylene terephthalate copolymer is prepared by reacting terephthalic acid or dimethyl terephthalate, ethylene glycol, compound (I) (e.g. 4-di(β-hydroxy ethyl)benzene) and compound (II) (e.g. 4-hydroxy benzoic acid methylester). Specifically, the addition amount of compound (I) and (II) [R=C1-3 alkyl is 5-30 mol.% respectively with respect to TPA or DMT, and their compositions is satisfied by the equation of 10 <=[(I) +(II)/(TPA or DMT)) x 100 < 40. In the equation, (I), (II) and (TMA or DMT) represent the mole numbers of their components.

Description

Process for preparing polyethylene terephthalate copolymer

1 is a schematic diagram of a fiber manufacturing apparatus used in the present invention.

* Explanation of symbols for main parts of the drawings

1: nozzle 2: heating zone

3: cooling synchronous 4: oil ring focusing guide

5,5 ': Pigtail guide 6,6': Godetrol

7: winder

The present invention relates to a method for producing a polyethylene terephthalate (PFT) copolymer, and more particularly, to a method for producing a polyethylene terephthalate (PET) copolymer suitable for ultra-fast spinning having a spinning speed of 6000 m / min or more.

Polyethylene terephthalate is prepared by condensation polymerization after esterification reaction or transesterification reaction of terephthalic acid (TPA) or dimethyl terephthalate (DMT) with ethylene glycol, melted and extruded by nozzle or slitter to make fiber, film have.

As a conventional method for producing fibers, especially filaments, undrawn or partially drawn yarns wound at a relatively low spinning speed have been used as a drawn yarn through a drawing process or a drawn yarn through a direct spinning drawing process. In particular, in recent years, a method of manufacturing a stretched yarn simply by spinning speed at a very high speed of 6,000 m / min or more has been developed, which has attracted much attention in terms of reduction of manufacturing cost such as personnel reduction and energy reduction. However, the filament produced by the ultra-fast spinning has very different properties in shrinkage rate, modulus, etc. compared with the conventional filament, and thus has many problems such as changing all conditions in the post-processing process.

However, the physical properties of the filament are derived from the change of the internal structure of the filament due to the ultra-fast spinning, and can be controlled in a certain range by changing the spinning conditions, but the fundamental properties cannot be changed.

For example, as described in Korean Patent No. 84-1172, the properties of the filament produced by the super fast spinning of PET homopolymer have the initial modulus of about 1,000kg / mm ² and the ratio of about 3%, which is a general process. Since it is significantly lower than the initial modulus of about 1,450kg / mm ² and about 8% of the number of non-aqueous PET filaments to be manufactured, it is difficult to develop the product in post processing.

In addition, US Pat. No. 46,634,23 describes a method for producing filaments by ultrafast spinning a copolymer prepared by copolymerizing a monomer having a structure as follows: 4-acetoxy alkyl benzoate and diacid of By the reaction, acetic acid is generated by a single amount of 4-acetoxy alkylbenzoate, so that the unit of diethylene glycol is contained in the polymer in a large amount, and thus the initial modulus of the prepared polymer can be improved, but the heat resistance is reduced.

Provided that R is H or an alkyl group having 1 to 2 carbon atoms.

Therefore, the present invention is produced by the ultra-fast spinning method of more than 6000m / min spinning speed, the physical properties of the polyester filament, in particular the non-aqueous and initial modulus is maintained as conventional PET homopolymer filament, and also easy to post-process such as weaving It is an object of the present invention to provide a method for preparing a polyethylene terephthalate copolymer.

Hereinafter, the present invention will be described in detail.

The present invention is prepared by injecting terephthalic acid (TPA) or dimethyl terephthalate (DMT) by polymerization method of polyethylene terephthalate (PET) homopolymer, terephthalic acid or dimethyl terephthalate When the compound of formula (I) and (II) is added to each of 5 to 30 mol% at the same time, the composition is added to satisfy the following formula (A) to prepare a polyethylene terephthalate copolymer It is characterized by.

In the above formula, R represents H or an alkyl group having 1 to 3 carbon atoms.

Here, [I], [II], [TAP or DMT] represents the number of moles of each component. Referring to the present invention in more detail as follows.

In the polymerization method of the present invention, the compounds of the general formulas (I) and (II) are added at the same time when preparing a known PET, and the equivalent of TPA or DMT and the general formulas (I) and (II) After esterification or transesterification with 110 to 190 mole% of ethylene glycol relative to the sum of the equivalents of the compounds of, the alcohol or water is distilled off and the unreacted ethylene glycol is removed. In the autoclave to produce a polymer by condensation polymerization in a high vacuum of 0.1mmHg or less.

At this time, the addition amount of the compound of the general formula (I) used in the present invention (II) is 5 to 30 mol%, more preferably 5 to 20 mol% based on the TPA or DMT, respectively, It is preferable to add the said General formula (I) and (II) compound in the composition which satisfy | fills the conditions of said Formula (A).

Here, more preferably than the conditions of the formula (A)

(Where [I], [II], [TPA or DMT] are the same as above).

Further, according to the present invention, if the value under the condition of the formula (A) is 10 or less, that is, the sum of the compounds of the general formula (I) and (II) is less than 10 mol%, the addition amount is small to achieve the object of the present invention. If it is more than 40 moles, the benzene ring is present in the polymer molecular chain a lot, the molecule is showing a rigidity, which is not suitable for medical use when made of fibers. In the compound of formula (II), R is preferably an alkyl group having 1 to 3 carbon atoms, that is, methyl, ethyl, isopropyl, normal propyl group, and the like, preferably methyl group.

In the polymerization of the present invention, on the other hand, a catalyst such as calcium acetate or zinc acetate may be used in the transesterification reaction, and a catalyst such as antimony oxide may be used in the condensation polymerization. Stabilizers can be used. In addition, the detailed conditions, such as temperature, vacuum degree, reaction time, etc. in the polymerization method are made under the same conditions as the production of known PET homopolymer.

As described above, PET produced by the method according to the present invention had good radioactivity and physical properties as a fiber when the intrinsic viscosity was 0.63 to 0.68. The PET was dried at 160 ° C. for 10 hours and then spun in a device as shown in FIG. Filaments were made at a speed of 6000 m / min. The filaments thus prepared have properties similar to those of conventional PET filaments when PET homopolymers are used in initial modulus (Mi) and non-number.

For reference, the manufacturing method of the fiber adopted in the present invention will be described in detail with reference to the drawings.

The polymer discharged from the circular nozzle 1 having a hole diameter of 0.23 mm and L / D 1.5 passes through the heating zone 2 at a distance of 10 cm from the nozzle 1, and the ambient temperature is 230 ° C. The filament passing through the heating zone (2) is connected to the oil ring focusing guide (4) located 90 cm below the nozzle (1) via the cooling air (3), which is 1st at room temperature via the pigtail guide (5) In the troll 6 and the second gothrol 6 ', it is roughened without a turn and then wound again in the winder 7 via the pigtail guide 5'. There is basically no speed difference between the two Godetrols and the winder, but a slight speed difference can be given to control the properties and winding tension.

Hereinafter, the present invention will be described in more detail with reference to Examples.

The measuring method of various physical properties in this invention is as follows.

1) Intrinsic Viscosity (IV: Intrinsic Viscosity)

It measured at 25 degreeC, changing the density | concentration of O-chlorophenol.

2) Initial Modulus

Tensile stress was measured at 1% elongation using a tensile tester at a chart rate of 250cm / min at 25 ℃.

3) Ratio (boiling contraction rate)

L is the length at load 0.1g / de and L * is the length at load 0.1g / de after immersion in the water for 30 minutes.

Comparative Example 1

PET filaments were prepared by a known method for producing a stretched yarn from an undrawn yarn using a PET homopolymer of IV 0.65.

Comparative Example 2

IV 0.65 dml PET homopolymer was used to make 75den 36 filament fibers with spinning temperature 290% and winding conditions as shown in Table 1 in the present apparatus.

Example 1

DMT 194g, ethylene glycol 112g, 4-di (β-hydroxyethyl) benzene [compound of formula (I)] 16.6g, 4-hydroxy benzoic acid methyl ester [compound of formula (II)] 22.8 in an autoclave g, calcium acetate 0.19g, antimony oxide 0.12g was added and the temperature was raised to 240 ° C, methanol was distilled out while stirring, 0.1g of phosphoric acid was added and stirred for about 10 minutes, and the temperature was raised to 290 ° C over 90 minutes and at the same time, at atmospheric pressure. After the pressure was reduced to 0.1 mmHg and continued to prepare a polyester of IV 0.64, fibers were prepared in the same manner as in Comparative Example 2 according to the winding conditions shown in Table 1.

Example 2

Performed in the same manner as in Example 1, except that 24.9 g of 4-di (β-hydroxyethyl) benzene [compound of formula (I)] and 4-hydroxybenzoic acid methyl ester [compound of formula (II)] 22.8 After adding g to prepare a polyester of IV 0.63, the fiber was prepared in the same manner as in Comparative Example 2 according to the winding conditions shown in Table 1.

Example 3

The procedure was carried out in the same manner as in Example 1, except that 33.2 g of 4-di (β-hydroxyethyl) benzene [compound of formula (I)] and 4-hydroxy benzoic acid methyl ester [compound of formula (II)] 15.2 After the g was added to prepare a polyester of IV 0.65, the fiber was prepared in the same manner as in Comparative Example 2 according to the winding conditions shown in Table 1.

TABLE 1

Claims (1)

In preparing a polyethylene terephthalate copolymer by adding terephthalic acid (TPA) or dimethyl terephthalate (DMT) by polymerization of a polyethylene terephthalate homopolymer, the following general formulas for terephthalic acid or dimethyl terephthalate when A method for producing a polyethylene terephthalate copolymer, characterized in that the compound of formula (I) and (II) is added simultaneously by 5 to 30 mol%, the composition of which satisfies the following formula (A).

In the above formula, R represents H or an alkyl group having 1 to 3 carbon atoms.

Here, [I], [II], [TPA or DMT] represents the number of moles of each component.

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