DE1504110A1 - Process for the production of a fine fiber product - Google Patents

Description

C 34 535 X / 39a Courtaulds Ltd ·.

DA-4O3

Description of the patent application

of the company

COURTAULDS 'LIMIiED
18 ,. Hanover Square,
London W. 1, England

concerning

Process for the production of a fine fiber Product

The invention relates to the manufacture of products or articles from mixtures of polymers and in particular on the production of articles with fiber-like properties,

It is known that mixtures of mutually incompatible Polymers and then the polymer

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New documents (article 7 SI Aba 2 No, sentence 3 dea change ",, * v 4. ₉₁₉₆ -.....,

Spinning mixtures to produce fibers with novel properties. The properties of the fibers depend of course on the polymers used and also on their properties in the mixture, the degree of. Compatibility and other properties. The threads produced up to now from different polymer mixtures have properties such as high volume or »shaking elasticity, toughness and low brittleness temperature. In British Patent 580,764, a method is described ben W, according to which two different polymers alongside stu a bicomponent fiber are extracted, so that the two components adhere to each other along one side. When this fiber is shrunk, the two components shrink to different degrees and the fiber curls.

It is also known "ultrafine fibers made from threads, which their turn from incompatible Polymergamischsn have been tet, by mechanical treatment of oriented threads so that the individual fibers are completely separated from the monofilament threads. (See. canadian. Patent 631 395) »Such fine fibers can be incorporated into paper.

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The process of making a fine fiber product, a mixture of at least awei with each other not Compatible or only limitedly compatible polymers is prepared, according to the invention, that one from the mixture a heterogeneous product with a polyfibril Structure forms and then the cohesion of the fibrils is reduced to such an extent that the greater part of the fibrils can perform an independent movement.

These fibril-like or fine-fiber products are in similar in many ways to the fibrous products that have been manufactured by conventional methods.

The products can be continuous threads with any cross-sectional shape or staple fibers made from them: they can be strips, rods, films or molded bodies which are manufactured in a known manner, e.g. by extrusion have been. As mentioned above, the polymers used as starting materials should not be compatible with one another so that at least two phases are present in the products formed from the mixture. So included the heterogeneous products usually particles of one or more polymers that are formed in a continuous

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! Phase of another polymer are dispersed. At least the greater proportion of the particles in the discontinuous phase must be inherently fibrin or become fibrin Let shape by weakening the material after the formation of the objects transferred, so that the objects a Get a polyfibril structure “This is how the polymeric continuous phase in the form of a network all around the fibrils of the discontinuous phase. The reduction in the cohesion between the polymers Particles, which di® coherent polyfibril structure form »then leads according to the invention to the objects dssi fiber properties, with a larger part of the fibrils can perform independent movements. Ss 1st not necessary that each fibril be completely different from others FlbrlHen remains unaffected when it has independent movements can perform. Preferably should be at least half ■ & ej? Piferules or very fine fibers independent movements can perform.

A particular interest is the fibrous Flächeng @ bilänn to, which have been prepared by the novel process from movies. Such products can be used in those fields in which the usual textiles are too expensive.

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Even if the products accessible according to the invention are relatively coarse compared to normal textiles that are processed into items of clothing, there are several areas of application where this property does not exist. occurs, e.g. when using underlay material and textile laminates. The yarn-like products made according to the invention from threads and tapes can be used like conventional yarns. Fibrous tapes are suitable for making cordage, ropes, bale wrapping material and twine. The advantage in the production of textiles, yarns and fiber ribbons is that many of the previously necessary or customary processing steps are no longer necessary. No special spinning and twisting process is necessary in the production of yarns or fiber ribbons, whereas weaving is not required in the production of textiles.

For normal purposes it is not necessary to have more than sv / ei polymers. Components in the. Present mixture to have (but of course can also Ansahl each of components used v / ground. Examples of particularly suitable mixtures lylon and polypropylene, nylon and polyester and polypropylene UNAE polyethylene.

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The initial mixture of polymers can be produced in liquid or solid state, the latter being preferred

is given. In this case, the polymers can be granulated or powdered form. It is advisable, however, that at least some of the mixture be preformed becomes »while the polymers are in the molten state, because a particularly intimate mixture, which which brings the best results, is most easily achieved in this way.

After mixing, the articles are made from the polymer blends manufactured. It is generally easy and economical to use directly from the molten mixture Help © a process, a. B. melt spinning or extrusion, to manufacture these items. Other methods, such as dry spinning from a solution of the polymer, can can also be used.

The methods of reducing cohesion between the Fibrils and to produce the fibril-like properties the products can be done in a variety of ways. The liature of treatment becomes natural largely dictated by the physical form of the opposing

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stands and on the properties of the Polymerisate · Ss therefore consider, for example, the treatment of a thread; it is possible to wholly or a component of the thread to be partially detached, whereby a structure is obtained that has numerous very fine, interlocking fibers for example obtained in the same way as a yarn which has been spun from staple fibers. The! Results give way of course, depending on the removed phase and the extent the distance from each other. Under certain ^ circumstances one can use a swelling agent rather than a solvent, for example if one of the polymers is very strongly hydrophilic and the others are hydrophobic. When one of the polymers in the blend has a melting point that is considerably lower than the melting point of one or the other components in the Hi-3c!: ü: - , the threads can be subjected to a heat treatment be, causing the fibrils or the agitation of low melting polymer melts and those of the high melting point Binding polymers together. This treatment is easier to carry out when the melting of the low melting polymer is brought about by shrinkage. Under extreme shrinkage conditions it is even possible to make a bulk yarn. A heat treatment

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does not necessarily have to include the actual melting, if the shrinkage itself is sufficient. Other treatments can be of a purely mechanical nature on the incompatibility of the polymers under the influence of a mechanical anti-sag treatment or another Treatment to separate the individual fibrils from the polymers to the extent required. Other methods are readily known to those skilled in the art.

Films made by the process of the present invention can take many forms, for example they can have a cellular structure when the polymer making up the discontinuous phase has been leached out; they can also take the form of a non-woven or non-knitted textile of the type in which a layer of substantially parallel fibers are bonded together.

It is not necessary to have the fibril-like properties of the objects directly after their manufacture from the polymer mixture to evoke? on the contrary, the objects can also be subjected to other procedures before this evocation.

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'This is how' threads 'can' films and similar extruded objects are advantageously stretched after extrusion. On the other hand, or in addition, the threads can become textiles interwoven or forfeited, which is followed by treatment to produce the fibril-like properties be subjected.

Manufactured from extruded films in accordance with the invention Products have greater strength in a straight * direction, i.e. in the direction in which the fibrils are oriented than in the other direction. If this property is undesirable, you can have two or more such ■ Films before or after the development of the fibril-like Connect properties with one another in a laminate-like manner, in which case it is desirable that the directions of orientation of the films are at right angles to each other.

Optionally, in the mixtures Zusätss gageben- advertising λ, modifisieren the au to the properties of the products obtained therefrom. Thus, "k iva. Emulsifier to admit herabausetzen the Telleiifjngrö'ße the components in -3er Scihmeiss'. .This has the effect that the fibrils in the finished product become smaller. Also, dyes may gegebenen-

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if "are incorporated into the weld pool," so can for example only one of the components "will be colored in the mongrel is present, making a speckled one Appearance "in the finished yarn results in» depending on how the Properties of the components vary »" '"

The invention also relates to eyeglass-like arrangements nungen- * which have fibrous properties and after the ancestors described above.

The following examples, in which the ropes are weight parts are, "-" explain the method according to the invention,

Equal parts of nylon 6 and polypropylene chips vairdan mixed together and heated to 2 ° 10 ° C. The melted mixture was ^ by a Sohra-ubenstrangpreÖToiTichtimg with a circular punch of diameter 6.35, ram _r hindurchgeaehiclct. The receptivity ivar ger ^ d., E _i; ^ ^ sufficient to strain the squeezed product on Walaeji without, zn stretch ",

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The monofilament material produced therefrom appeared homogeneous be nice, but a passage between calender rolls showed that it was composed of numerous individual fibers if the desired fibril-like properties were caused.

Example 2

Equal parts of nylon 6 and polypropylene were mixed as in Example 1 and heated together.

The garrison was made through a slit 3 »175 wide extruded and drawn into take-up rolls without being stretched at this point. The cooled product was then stretched lengthways to about three times its original length, followed by through mechanical vibration of the oriented film was broken into a web of pibrils.

Example 3

Two mixtures, a and b, were once made from equal parts Nylon 6 and low density polyethylene and in the other case made from three parts of the former and part of the latter substances.

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Honofile were spun from the two mixtures and in the case of mixture a using a punch with a diameter of 2.286 mm and in the case of mixture b using a 6,762 mm diameter punch. The stretching of the filaments resulted in a 300 # increase in length and a decrease in the diameter of the

Threads from 1.143 mm to 0.381 ram.

The threads were contiguous until they were subjected to mechanical impact treatment in which the fibrils were separated from each other.

example A.

The procedure of Example 3 was repeated using nylon 66 and polypropylene. The threads developed a fine fibrous texture during mechanical treatment Structure. .

Example 5

Three mixes were made using equal parts of the following components:

a) Nylon 6 and low density polyethylene

b) 6 nylon and high density polyethylene

c) nylon 6 and polypropylene.

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Films were made from each mixture by putting them through a nozzle with a width of 0.508 mm was squeezed out. The PiIm from the mixture a was in a water bath with a squeezed out such a recording speed that gave a film 0.127 iara thick. The films from the mixes b and c, which are picked up by a chilled roller were 0.127 mm thick.

The films developed a highly oriented, fibrous appearance

Structure with repeated turns, ™

Claims

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Claims (3)

Claims rU. _; · Sum method of producing a fine fibrous product, wherein a mixture of at least two mutually incompatible or only "limited compatible polymer is produced, characterized ge Jc e η η - - characterized in that from the mixture a hetero- forms a natural product with a polyfibril structure and then reduces the cohesion of the fibrils to the extent that that the greater part of the fibrils are independent Can perform movement. 2. The method according to claim 1, characterized in that the heterogeneous product by Extrusion "forms. ^ 3. Method according to claim ? _t characterized in that the product is pressed out as a continuous film. 4. The method according to claim 2, characterized in that the extruded product is formed as a film. - 14 -90 9833/12 58 New. Documents (Art. 7 SI Paragraph 2 No. 1 Clause 3 of AuftrunwM. V, 4.9.196. 1604110 TS 5. The method according to claim t to 4, characterized in that the product is stretched »before 6B is made into a fibril-like product. 6. The method according to claim 1 to 5 »characterized» that a mixture with two polymers is used · 7. Method according to claim 6, characterized in that J ε ei ch η e t that the two polymers are a polyamide, polyethylene, polypropylene and / or a polyester used. 8. The method according to claim 1 to 7, characterized in that the cohesion of the fibrils by mechanical impact reduced. 9. The method according to claim 1 to 7 * thereby g e k e η η - a e i c h η e t that one can make the cohesion of the pibrils through a heat treatment decreases. 10. The method according to claim 1 to 7ι g β k e η η -zeichne t that the cohesion of the pibrils through Reduced exposure to a solvent - 15 - 90 ** 33/12 58 ■ original bad _Β draw t, one DAFL oils EohUsilon the Pibrillen by combining a Viärmelceh ^ Mliiog and a mechanical JSinv / MPACT reduced - 11. The process "i oh hi claim 1 β 7» dae.urch geke η η BATH ORIGINAL 16 - 909833/12 58