DE1760293A1 - Continuous process for spinning and drawing polycaproamide threads - Google Patents

Description

patent attorney
Munich s

REICHENBACHSTR. 51 TEL 16 3i 51

Polio 12 218

Allied Chemical Corporation, Ncvr York, N.I., USA

Continuous process for spinning and drawing polyoaproaznide filaments.

The invention relates to the melt spinning of polycaproamide threads and in particular multi-ply yarns with subsequent Drawing the chilled thread or gaois without the interposition of a winding ...

Usually Polyoaproamidfädeü in © ine cooling zone, for example a vertical tower in which they go through Air cooled, extruded and then at the outlet end der'Kühlzone wound up under low tension. Immediately prior to winding, a sight sealing means is used in the form of an aqueous etoulsion on the Jädan

209817/1091

applied to facilitate their further processing. The wound threads are kept in an atmosphere of constant humidity ("lagged") and later stretch out, ma to orientate the molecules and the Improve the tenacity of the thread (measured by the tear strength). Such procedures are in the USA Patents 2,282,860, 2,918,347 and 3,113,363. .

The process would, of course, be greatly simplified if one could omit the winding up of the undrawn yarn and the exit end of the cooling laon, the keeping of the yarn in the atmosphere of constant humidity and the unwinding of the yarn for drawing. Processes including continuous spinning and drawing without these measures are described for threads and yarns made from Pclyhoxeijothylenadiparaid, ie nylon-66, for example in the USA patents 3,090,997 and 3,093,581. In the vast majority of these patent specifications, only one example (XIV) mentions polycaproamide and according to this example the tuner-stretched yarn is wound up ("packaged ^11" ) and pre-stretched in a separate process stage, i.e. not continuously extruded and stretched.

BATH ORIGINAL

209117/1091

The continuous extrusion and drawing of foil polycaproaaid encounters particular difficulties such as the breakage of filaments to form soles from the drawing rolls, although the tenacity (tear strength) is at least 4 g / denier based on the dimensions of the undrawn yarn. These difficulties can be attributed to the fact that folyeaproamide is able to exist in three different crystal fora which can transform into one another (TgI, Rolldan & Kaufman, Journal of Polymer Science, Seil B, Volume 1 (1963) (Polymer letters). Pages 603-60 «*).

Sin in the VSK Patent 3,053,611 described a method for overcoming the difficulties of the continuous spinning and drawing of Polyeaproaaidgarn is that the threads are still hot stretched in the Spinnkaomer place in a cooled state, "but Siesee method brings its own ^one difficulties" it eich because it places very high demands on the equipment used, so that the tension, thread running speed and efthl speed remain as uniform as is necessary for good uniformity of the yarn. The devices used do not easily meet these requirements, especially when

209817/1091

-H

the yarn consists of a large number of single threads, for example 30 or more single threads.

The invention relates to a process for the continuous spinning and subsequent stretching (molecular orientation) of a poly- caproaild yarn by extruding a number of individual threads into a sasktthlsone from a melt containing al0 the main constituent poly- ^ - cafroamid, cooling the threads in this zone and then * the drawing of the cooled threads. Bas method is characterized in that the swath kg continuously at a rate of 11.34 / extndiert h, the temperature of the filaments duroh · seen up to not more than 55 ⁰ O, called a standing with the threads in Eontakt resistance thermometer, lowers and the yarn emerging from the cooling zone is continuously fed into a veretreckeono:. » which it is drawn at a spread ratio of at least 3.5: t.

A3 it was found that a poly - ^ - caproaoid yarn including a high denier yarn per thread, for example 40 to 100 denier per thread (undrawn) _; continuously at a high speed of at least 11.34 kg / h and with a rapid exit speed from the cooling zone ~ νοτ * ;;, # 05 m / min, extrid; Urt and

BATH ORIGINAL

7 "

this yarn can be stretched continuously without being wound up, "at a stretching ratio of 3.5: 1 if the extruded threads are intensively cooled" before they are stretched. The birefringence of the undrawn threads is no more than 0.005. In particular, when the invention is lost, a relatively large number of strong single threads, namely at least about 60 single threads with a denier of about 40 to 100 (undrawn), are eroded into a single cooling zone, and these broken threads are cooled with cooling air, with a flow rate of about 6.2 to 18.7 3i per kg incoming threads (standard temperature and pressure) and does not enter at an inlet temperature of preferably above 35 ⁰ O in Kühlscbacht. The cooling air in the Kühlsono is expediently directed in different directions. A small portion, in particular 1 to 25 #, of the total incoming air flows up and is discharged next to the spinneret, while the main part is further divided by having it for a week with two air inlets * of which the first is at least 1.52 ° above the main outlet zone and the others are at least 1.5 2 m below this main exit & zone.

The drawing is a flow chart showing the main features of the invention. The yarn 1 is in the

209817/1091

The form of threads is extruded from a spinning block 4 into a cooling duct 2. Era upper end of the cooling shaft there is an air distributor 6 and above a collecting space for monomer 8. From the air entering the ■ distribution chamber S a little 'flows Part up to SaumeIraum 8 and from there to outside, while the main part of the incoming air in the same direction as extruding threads downwards flows and is drained to the outside via a collecting space 10. More air flows from the lower end of the dee

Chute 12 at the exit point of the threads into the chute and flows in the opposite direction to the thread path into the collecting chamber 10 and from there outwards another Yertell chamber can be provided. Be ¹ such an allocation and supply of the cooling air ^let it possible to control the temperature and humidity regardless of the air of the environment.

Sound the lower end of the outlet 12 deodorant Kühlschaohtes the threads run over a standard thread cleaner 1 * and then via a standard equipment scale 16. From there

209817/1091 bad original

the yarn runs around the first Streokwalse 18 and becomes between this and the sv / sitsn stretch orphan 20 stretched. A third roller 22 can be provided * if the δοτή still through a v / eitero treatment zone, "for example a heat treatment zone

Boll. By means of a dishwasher 24, the yarn is either directly from the second drafting roll or after it has the mentioned further treatment zone, for example a heat treatment zone equipped with a heating device 26 has passed through, wound up by the third draw roller 22.

The temperature of the O-arnes immediately after its exit from the ducts "ff voltage 12 can be measured by placing it in Eontakt with a resistance thermometer 30 performs. According to the invention this should S.saperatur 55 ⁰ O or less", respectively.

In the following examples, the numerical values in the table are zueammengestellt, preferred embodiments of a de traversed the invention are compared Vergleiehöbeispielen to illustrate ¹ that dia compliance with the claimed conditions is essential for the success of the process,

209817/1091

For example, a spinning apparatus with a smooth spinning block, customary for melt spinning, with a spinning plate with 136 spinning nozzles, each 0.457 mm in diameter, was used. Under the spinning plate there was a vertical shaft with an air distribution channel 0.30 m underneath the spinning plate, a collecting space for cones above the air distribution chamber and a main air supply chamber, about 3.66 m below the distribution chamber for the incoming air , 4 m above the lower end of the shaft. The G & nse shaft was about 6.71 m long. The structure of such a shaft is illustrated in detail in US Pat. No. 3,257.

Dia temperature of the incoming air was 2Q ⁰ C and i hro relative humidity at this temperature for 65 #. This air was when the 7erf akran of the invention was carried out at a speed of 1.133 m / min. (Level, temperature and pressure) sucked into the shaft through the air distribution chamber 6, where the air flow rate varied in the other approaches, given in table ai). When * carrying out the Terfahrenp of the SrfJ.udung tvab άϊο air kit a Geechwindig-P; oit of 2.263 m / min. durcl · die HauptteenrmeJJcttmracr au β »ά in aliofl An & lilzcm vv.rdi ¹ .- '. about d.?o

7 0 Π η 1 11- Γ) 9

^ 9 "

at the upper end of the shaft 0.425 Ms 0.56 6 n ^ / min. Air and MonoEier &üKipx'ß sucked out. Differences between incoming and outgoing G-aoen and Dampfen were due to the lower end of the shaft, where the threads emerge from it. " xarbev the KauptluftearnmelTcainrier entering or exiting! calls balanced.

The temperature of the shrimp before extrusion through the nozzles "was about 257 ⁰ O and the rate of extrusion 18.1 kg / h or (Example 2} 13.6 kg / h"

The room temperature at the outlet end ds ε. The shaft was measured by means of a resistance thermometer, i.e. a commercially available temperature-sensitive semiconductor encapsulated in glass atie sintered metal oxides with a resistance of about 100,000 ohms at 20 ⁰ C, the resistance of which has a negative temperature coefficient, measured, the yarn in contact but the resistance thermometer running _o

After the yarn emerges from the cooling shaft, it is placed on a finishing roller with a non-aqueous one Equipment provided and then runs in three turns over a stretching shaft (eiu.s Vialr «e and oinsio Tronnstift),

BATH ORIGINAL

2 0 9 8 1 7/1 Γι 9 1

so that the yarn is treckt before. "then in three turns on a second, calibration with higher Ümfang3g3sciiwindi3keit rotating as the first stretch roller, and then in a usual Parallelspuj.maüchine _f by which it is wound under a slight gesteusrcen train. The stretching reserves given below are the ratios of the circumferential speeds of the second and first stretching rollers.

The conditions used in Examples 1 and 2 according to the invention and the comparative examples and the phyeikalsohen properties of the obtained stretched Yarn (measured on the Loetron tensile tester) are given in the table. All conditions except those given in the table were the same.

Tabel

Cool-

out-

air

5inla3 Auelaß ⁰ C

Comparative BessiG-Ie

example

B.
C.

0.566 H2

1.70 1.1 »75

2.85 2.266 65

1.155 2,266 52

Example _χΛ ^

Double Kazi- Physi- Own

refraction 3 & I03 kali- schcf

of not being aware of it

stretched-σtrek- tear- tear-

ten Ga? nc 3a «33- deh- feetis

holding wedge

nis f> g / den.

0.50

0, over 25
0.0! 5
0.004

0.002

5.05 70.1

5.85 56.0

4.00 50.4 BATH

4.8

The yarn of Example 1, which has not been subjected to any heat treatment, worien had shrinkage in boiling water of about $ 20, this value could be obtained by heat treatment be considerably belittled and this belittling the shrinkage was accompanied by an increase ^ the elongation at break with little or no change the tear strength.

Εε "not the Kühlsohaoht a temperature above 55 ⁰ G has, at a draw ratio υ on at least 3» striking da3 the yarn as ec au at its outlet 5 can be drawn while the Reißdehzmng of the yarn is not more than 60 ^ .

In particular, when high denier threads, for example 4-0 to 100 denier per undrawn thread, are to be processed, it is essential to use a draw ratio of at least 3-5. Less stretched threads generally have one relatively low tensile strength and one relatively high elongation at break. Außerdezi siiehan Aich them continuously spun yarns and verntreckten b <?. standing up "considerably cusaumen again. Ι'ρ.5ι · το" ί ^ ea u can a 7erfonrimg of aufgeepulton yarn ^ aKetB koiTimen nivl the Wiiiduü mm ^ ot) dsf. Qi ^a .i: <H? k'drvjGp. nioh v.ntarej.rn * idor v

· '■ «" ⁽ⁱ ''' ¹ »'« ¹ BAD OR ₁ Q ₁ NAt

41-

can. Wexra a large package is spooled tight enough to adhere to axa core, through such a contraction dee vex * stretched yarn even blasted the core be o

According to the invention, the yarn can have a sufficient Dimensional stability can be given so that packages of 0.9 kg and more can be wound on / earthed. This dimensional accuracy can be achieved by subjecting the yarn to a heat treatment or by subjecting it to a lesser one than the maximum applicable draw ratio stretched (i.e. with a lower stretch ratio as the highest, at which no more than 0.13 in total resulting from broken threads Loops on the rollers and tears of the green in the Verstreekungssone (\ <raps and breaks) per kg spooled Yarn occur). The heat treatment can be done by running the yarn through a heating zone either keeping its length constant or allowing a limited contraction. Suitable heat treatments are described, for example, in TJSA patents 2,199,411, 2,803,108 and 2,859,472. If desired the heat required for the heat treatment can be fed directly to the second stretching drum,

209817/1091 bad

for example v / Ir described in aer ¹ USA Ρε.ΐanfcschrift 2 611 923i

The high shrinkage of Ri 3am produced according to the c-sm method of the invention came about, for various well-known Sworko. been exploited _e example twisted scanning a yarn with a high shrinkage yarn having a low shrinkage, to be swallowed or in other konbinisrt Wgj.3G, εο that when such Mehrkismponentengarn Schrampftaigebedingungen, beispielswelpo dry heat or a hot aqueous Bai auBgesetst is, the difference of the Shrinkage causes puckering or folding of the yarn. A yarn of such high Schrrnrpfuug can too! Duroh looks different Y ^ ixmeEie-vhoden, such as the famous 919 known Heißkantenkräuselimg and & vs the üSü Patent 2 391 97Λ from the US PafcantBchriften 2,875,502 and 2 HeißatiftkrauGGluni ;, kräueoln.

The above 7 similar versions have been made with one major made of polycaproamid, poljxiar diarcfcge " leads. Dfti3 '/ experience of the invention can also be applied to Threads, which are a larger part of polyeapcoaroid, can be applied. For example, there can be patterns of

BAD ORIGINAL 2 0 9817 / »091

Polyca; Roamid with a compatible polymer or dispersions of an incompatible polymer in polycaprolactam in the same way as described in the examples ", and with the same or similar results. Examples of such mixtures are mixtures"; of polycaprolactam with a smaller proportion other polyamides, such as Nyloa-66 or Kylon-6,10 or a polyamide of a diacid and a diamine containing a ring, for example a diamine, since it contains an aromatic or cycloaliphatic ring; or a polycaproamide in which a polyester, such as polyethylene terephthalate; or a polyolefin or a polyvinyl compound such as poly & Thylen, polypropylene, or polyvinyl chloride Polyotyrol; or Bin Acrylpolyner such as polyacrylonitrile or Polyisetaylmüi; hacrylat; or a copolymer, · or a GremiBch such polymers dispergiort i.3t.

Others can also be present in the material to be spun Modifiers, such as pigments, stabilizers and Lubricants, such as for example in the USA patents 2,705,227 and 3,242,134, 'be present.

BAD ORIQiNAU

209817/1091

Claims (3)

P a teat a η ε ρ r ü C ₁ Ji ₁ c 1 “Process for the continuous spinning and subsequent drawing (molecular orientation) of a poly capoamide yarn3 by extruding a number of threads into a gas cooler from a melt containing poly capricide as the main component, cooling the threads in this Zone and subsequent stretching of the cooled threads »ά ad, ur ο hge lce'iinseichnet that the melt is continuously extruded at a rate of 11.34 kg / h» the temperature of the? Ädöa up to not above 55 ⁰ C, measured by means of a resistance thermoiaa fcer in contact with the filaments, and the yarn emerging from the cooling zone is continuously fed into a drawing zone , in which it is drawn to a draw ratio of at least 3.5: 1, 2. Procedure nacl ?. Claim!, Characterized in that vronigetene 6C single threads at the same time · in the ITÜhlzone extrudiort., v? ol? ei each pad has a denier in the undrawn state in the range of 40 Με 100, and the thus obtained BATH ORIGINAL 509817/1091 Yarn continuously at a speed of at least 305 ra / min. be led to a Verctreckungsssone. 3. The method according to claim 1 or 2, characterized in that the Teaperaturoenken of the extruded threads "is effected by the fact that one Threads with air with a temperature of not more than 35 ⁰ O, which enters at a speed of 6.2 to 18 * 7 m / per kg of intretende threads (standard temperature and pressure), comes into contact and brings a small part of these into contact Air leads upwards in the vicinity of the jpinnplatte, while the greater part is discharged via a main air collection zone between two air inlet zones, one of which is at least 1.52 m above the main collection zone and the other at least 1.52 meters below this saramel zone. BATH 209017/1091