JPS58186611A - Spinning method for polyester fiber - Google Patents

Abstract

PURPOSE:A polyester such as ethylene terephthalate polymerized together with a specific amount of polyether which is added at an arbitrary stage is subjected to high-speed melt spinning to produce the titled fiber with inhibition of crystallization on molecular orientation without yarn breakage and strength reduction. CONSTITUTION:When a polyester is subjected to melt spinning at a taking-up speed of higher than 2,000m/min, the polyester is prepared by polymerizing ethylene terephthalate units as a major component together with a polyether of the formula (n is integer of 2-5) such as triethylene glycol which is added at an arbitrary stage before the polymerization completion in an amount of 0.01-1.5mol%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for spinning polyester fibers, and more particularly to a method for melt-spinning a polyester fiber at a take-up speed of 2,000,111 per minute or more.

Polyester, represented by polyethylene terephthalate, has many excellent properties and is used for a variety of purposes.
It is especially widely used in fibers. Polyester fibers are
It is usually used by melt spinning, stretching, and heat setting. In recent years, due to advances in silk spinning technology, the take-up speed during melt spinning has increased from the conventional 1 ooo to 1 soo@/min to 2 ooom/min or more, and even 2500 to 40 G (1 m/min).
It has now become possible to significantly increase the temperature up to 1 minute. In particular, intermediately oriented undrawn yarn obtained at a take-up speed of 2,500 to 4,000 doors/min is usually directly subjected to stretching, false twisting, and crimping, and this application has been rapidly progressing in recent years and has become the mainstream of yarn spinning technology. is being achieved.

On the other hand, attempts have been made to further increase the take-up speed to 4000 m/min or higher. However, such ultra-high-speed spinning has the drawback that yarn breakage occurs frequently during spinning, and furthermore, the strength of the product yarn decreases. In order to eliminate this drawback, attempts have been made to optimize the spinning conditions, such as spinning temperature, cooling air volume, cooling air temperature and cape, and to improve the structure of the spinning tube and spinneret nozzle, but these measures have their limits. , no significant improvement can be expected.

The present inventor investigated the cause of the above-mentioned drawback and found that polyester has a property that it is difficult to crystallize compared to polyethylene, polyamide, etc., but the take-up speed during melt spinning is 200%.
When the speed exceeds 0 m/min, molecular orientation occurs and crystallization occurs as a result.This tendency becomes particularly noticeable when the speed exceeds 400 m/min, and the orientation of the spun yarn has not progressed sufficiently. Despite this, it was found that crystallization progressed significantly, which caused the above-mentioned drawbacks.

Based on this fact, we further investigated the crystallization behavior of polyester, which is highly oriented and has low crystallization during high-speed spinning, and found that the 7-inch hepamine compound used as a polymerization catalyst for polyester is the core of polyester. Although this antimony compound acts as an agent, it has been learned that it has the effect of suppressing crystallization during molecular orientation during high-speed spinning, although this is not sufficient.

Furthermore, as a result of studying various additives to suppress crystallization during molecular orientation, we found that using polyester obtained by adding a specific amount of triethylene glycol before the polyester manufacturing reaction is completed, 11 The present invention, in which the effects were found to be more effective, was completed as a result of further studies based on these findings.

That is, in the present invention, when polyester is melt-spun at a take-up speed of over 100%, ethylene terephthalate is used as the main constituent unit of the polyester, and at any stage before the polycondensation reaction is completed, the following general formula (1 ) Spinning of polyester fiber characterized by using a polyester obtained by adding 0.01 to 1.5 moles of polyether represented by the formula % (1) to the acid component constituting the polyester. It's a method.

In the present invention, 115 polyester mainly refers to polyethylene terephthalate consisting of a terephthalic acid component and an ethylene glycol component. It may be a substituted polyester, or a polyester in which a part (usually 20 moles or less) of the ethylene glycol component is replaced with another diol component. Furthermore, various additives, such as dyeing agents.

It may also be a polyester copolymerized or mixed with a flame retardant, an antistatic agent, a hydrophilic agent, a colorant, etc. as necessary.

Such polyesters are usually produced by esterifying terephthalic acid and ethylene glycol, by transesterifying a lower alkyl ester of terephthalic acid such as dimethyl terephthalate with ethylene glycol, or by reacting terephthalic acid with ethylene oxide. It is produced by producing a glycol ester of terephthalic acid and/or a low polymer thereof, and then heating this product under reduced pressure to cause a polycondensation reaction until a predetermined degree of polymerization is achieved.

In the present invention, a polyester obtained by adding a polyether represented by the following general formula (1) % formula % (1) before the polyester production reaction is completed is used. Such polyethers include diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol,
Among them, triethylene glycol and tetraethylene glycol are preferred.

If the amount of such polyether used is too small, the effect of suppressing oriented crystallization will not be obtained, while if it is too large, the softening point of the polyester obtained will decrease or the yellowish tinge will increase. The amount may be appropriately selected from the range of 0.01 to 1.5 molty, preferably from 0.05 to 1.0 molty, based on the functional carboxylic acid. Further, it may be added at any time until the polyester production reaction is completed, and may be added to other additives used in the polyester production, such as catalysts.

It may be added at the same time as the stabilizer. In addition, when adding, it may be added as is or after being dispersed or dissolved in a suitable solvent such as glycol.

When the polyester produced by the method of the present invention is melt-spun at a take-up speed of 2,000 m/min or higher, oriented crystallization is suppressed especially in the high-speed spinning range of 4,000 m/min or higher, so the yarn during spinning is In addition to significantly reducing breakage,
There is also a tendency for the strength of the yarn to increase. Note that as the spinning conditions, polyester melt spinning conditions can be arbitrarily adopted.

Next, the present invention will be explained in further detail by giving examples.

In the examples, parts are parts by weight, and [η] is the intrinsic viscosity determined from the value measured at 30° C. in an orthochlorophenol solvent. - The color tone and b value, which represent the color tone of the polymer, are values measured using a Hunter type colorimeter, and the larger the L value, the higher the whiteness, and the larger the b value, the stronger the yellowish tinge. It shows. In addition, thread breakage during spinning is 1
00 (2, sky winding) It is indicated by the number of threads that break during winding.

Example 1 970 parts of dimethyl naphthalate, 6 parts of ethylene glycol
40 parts and 0.3 manganese acetate as transesterification catalyst
One part (25 mmolti to dimethyl terephthalate) was charged into a reactor equipped with a stirrer, a rectification column, and a methanol distillation condenser, heated from 140°C to 230°C, and methanol produced as a result of the reaction was distilled out of the system. The transesterification reaction was carried out while The internal temperature was 230 3 hours after the reaction started.
°C and 320 parts of methanol were distilled off. Here, 0.18 parts (2 parts) of trimethyl phosphate was used as a stabilizer.
64 rimorti to dimethyl terephthalate) was added, and after reacting for 10 minutes, antimony trioxide (0,
44 parts (30 mjJ molti to dimethyl terephthalate) and 2.91 parts of titanium dioxide as a matting agent, and
3.7 s parts of triethylene glycol (o, s molyte to dimethyl terephthalate) was added and reacted for 20 minutes to complete the transesterification reaction.

Next, the obtained reaction product was transferred to a polycondensation reactor equipped with a stirrer and a glycol condenser, and heated from 230°C to 2°C.
The polycondensation reaction was carried out while gradually raising the temperature to 85°C and lowering the pressure from normal pressure to a high vacuum of 1 kg. At a polycondensation reaction time of 3 hours and 30 minutes, [η) was 0.64 and the softening point was 261.
9℃1 Hue value 72.0. A polymer with an L value of 7.5 was obtained. , this polymer was spun at a spinning temperature of 290°C and a discharge amount of 38 g/
minute, cooling wind linear velocity 15 m/min (26°C.

A 115 denier/36 filament intermediately oriented yarn was wound for 7 minutes at a relative humidity of 70% and a take-up speed of 5 ooo. This intermediate ship of the same type has △n (birefringence) 0.057 and hot water shrinkage rate (shrinkage rate after 30 minutes treatment in 60°C warm water) 62
The strength was 2.79/denier at 1%, the elongation was 1 as%, and there were no yarn breakages during spinning.

Next, this intermediately oriented yarn was stretched with a high-speed false twisting machine using a urethane disk at a stretching ratio of 1.53 times, a heater temperature of 220°C,
A processed yarn of 75 denier/36 filaments was wound at a yarn speed of 7 ooms/min. No processing yarn breakage was observed.

Separately, the above polymer was spun at a spinning temperature of 290°C and a discharge amount of 40 g.
/min, cooling air closing speed 15m/min (26℃, relative humidity 70
%), the 75 tenier/24 filament was wound at a drawing speed of 5000 @/min.

This filament is △no, to9. Elongation is 60 inches.

Strong &3.91i'/denier and strong order are sufficient,
Furthermore, there were no yarn breakages during spinning.

Comparative Example 1 Example 1 except that triethylene glyfur was not added.
I did the same thing. The obtained polymer was [da] 0.6
4, Softening point: 262.5°C, Hue value: 71.0. b value 8
．． It was 0.

The intermediately oriented yarn obtained at a take-up speed of 3000 @/min has △n 0.
04 B, hot water shrinkage rate 411 strength 2. sti/denier and elongation of 120 inches, and five yarns were broken during spinning. When this intermediately oriented yarn was false-twisted, the number of broken yarns was 15, which was poor.

In addition, the filament obtained at a take-up speed of 5ooo*/min is △
no, 085. The elongation ro% and strength were low, 3.21/denier, and the number of yarn breakages during spinning was 20, which was extremely poor.

Example 2 The same procedure as in Example 1 was carried out, except that 4.85 parts of tetraethylene glycol (O,S molti to dimethyl terephthalate) was used in place of the triethylene glycol used in Example I. The first polymer is [η)f
l, 64. Softening point 261.7℃ 9 Hue value? 1.9. b
It was 7.7.

Pick-up [Intermediately oriented yarn obtained at 3000@/min is △no, o
I5g, #l water shrinkage rate 63cm 1 strength 2. ty/tenier and elongation of 136%, and there were no yarn breakages during spinning. When this intermediately oriented yarn was false-twisted, the number of broken yarns was zero, which was good.

In addition, the filament obtained at a drawing speed of 3000@/min is △
nO was 110, elongation was 61 cm, strength was 3.9 g/tenier, and there were no yarn breakages during spinning.

Example 3 860 parts of terephthalic acid and 390 parts of hyethylene glycol were charged into a pressure-resistant autoclave, and 3 kg/kg was charged with N.
The esterification reaction was carried out at 220 to 260° C. for 3 hours under a pressure of . After about 180 parts of water was distilled off, 0% trimethyl phosphate was added as a stabilizer.
．． Add 0.4 parts (5 mmol of terephthalic acid) and
°min MKi [antimony trioxide 0.45 as condensation catalyst]
(30 mmol to terephthal IN) and 3.8 e parts (o, s mole to terephthal IN) and 3.8 e parts (o, s mole to terephthal IN) and 2.5 parts titanium dioxide as a matting agent.
8 parts were added and reacted for 10 minutes to complete the esterification reaction. Next, a condensation reaction was carried out in the same manner as in Example 1, and the total polycondensation reaction time was 3 hours, and [η) 0.64,
Softening point: 260.1°C.

Hue value 68.0. Polyethylene terephthalate with a b value of 4.5 was obtained. Then, in the same manner as in Example 1, lli!
The intermediate oriented yarn obtained by melt spinning is △nO,05G
, hot water shrinkage rate 63% 9 strength 2.811/denier, elongation F
Length was 134 cm, there were no yarn breakages during spinning, and no yarn breakage was considered.

Further, the filament obtained at a take-up speed of 3000@/min was △no, 116. The elongation was 5S%, the strength was 4.211/denier, which was sufficient, and the number of yarn breakages during spinning was very good, with no breakage.

Claims (1)

[Scope of Claims] 111 When polyester is melt-spun at a take-up speed of 2000 k/min or more, ethylene terephthalate is the main constituent unit of the polyester, and at any stage before the production reaction is completed, the general formula F is used. (1) A polyester characterized by using a polyester obtained by adding 0.01 to 1.5 mol% of polyether represented by the formula % (11) to the acid component constituting the polyester. (2) The method for spinning polyester fibers according to item 1, wherein the polyether is triethylene glycol and/or tetraethylene glycol.