KR102435385B1 - Polymer fiber with improved long-term dispersibility - Google Patents

Abstract

Polymer fibers with improved dispersibility. The present invention relates to a polymer fiber having improved long-term dispersibility, a method for producing the same, and a use thereof.
The polymer fiber according to the present invention comprises at least one synthetic polymer and an agent present on the surface of the fiber, wherein the agent is carboxymethyl cellulose (CMC), methyl cellulose (MC), ethyl cellulose (EC), hydroxyethyl Cellulose (HEC), hydroxypropyl cellulose (HPC), methylethyl cellulose (MEC), hydroxyethylmethyl cellulose (HEMC), hydroxypropyl cellulose (HPMC), ethylhydroxyethyl cellulose, carboxymethylhydroxyethyl cellulose, and two or more cellulose ethers selected from the group of mixtures thereof.
The polymer fibers according to the invention have improved dispersibility and are therefore suitable for preparing aqueous suspensions used, for example, in the formation of textile fabrics, for example nonwovens.

Description

Polymer fiber with improved long-term dispersibility

The present invention relates to a polymer fiber having improved long-term dispersibility, a method for preparing the same, and a use thereof.

Polymer fibers, for example fibers based on synthetic polymers, are industrially produced on a large scale. In this case, the basic synthetic polymer is produced by a melt spinning process. For this purpose, the thermoplastic polymer material is melted and guided in the liquid state by means of an extruder into a radiation beam. Molten material is fed from this beam of radiation into what are known as spinnertes.

The spinnerette generally comprises a spinneret plate provided with a number of apertures through which individual capillaries (filaments) of fibers are extruded.

In addition to melt spinning, wet or solvent spinning is used to produce staple fibers. In this case, instead of the melt, a high-viscosity synthetic polymer solution is extruded through dies with fine pores. Both methods are known by those skilled in the art as multi-position spinning methods.

Polymeric fibers produced in this way are used for textile and/or technical applications. Here, it is advantageous for the polymer fibers to have good dispersibility in aqueous systems, for example for the production of wet-laid nonwovens. In addition, if the polymer fiber has a good and soft grip, it is advantageous for textile applications.

Modification or finishing of polymeric fibers, for example stretching and/or crimping, for a specific final application or necessary intermediate treatment steps generally results in a suitable finish or layer applied to the surface of the treated final polymeric fiber or the polymeric fiber to be treated. This is achieved by applying

Other possibilities for chemical modification can be achieved in the polymer backbone itself, for example by incorporating compounds with flame action into the polymer backbone and/or side chains.

Additionally, additives such as antistatic agents or dye pigments may be incorporated into the molten thermoplastic polymer or into the polymer fibers during the multi-position spinning process.

The dispersion behavior of polymer fibers is influenced in particular by the properties of the synthetic polymer. Especially in the case of thermoplastic polymer fibers, the dispersibility in aqueous systems is therefore influenced and controlled by the finish or layer applied to the surface.

The dispersibility created or improved by suitable finishes or layers is already sufficient for many textile applications.

For food-related uses, however, other requirements apply; The substances and materials used are EU Reg. No. 231/2012, contact with food must be permitted. whether the provided polymeric fibers are provided in dispersed form for a relatively long period of time and/or in more extreme conditions, such as high pressure, strong shear, and high temperatures, in particular aggressive and acidic aqueous systems, and whether such dispersibility is relatively long Not maintained even after storage time is additionally needed.

Therefore, improved dispersibility, in particular long-term dispersibility, which has good dispersibility even after a relatively long-term storage, and EU Reg. No. The object is to provide a polymer fiber, which is approved for food contact according to 231/2012.

In addition, polymeric fibers can be subjected to extreme conditions, such as high pressures, severe shear forces and elevated temperatures, especially in aggressive aqueous systems optionally with pH<7 and/or electrolytes, in particular saline-based electrolytes, even after prolonged storage, It should easily maintain good dispersibility.

The object is one or more synthetic polymers, preferably fibers on the surface of carboxymethyl cellulose (CMC), methyl cellulose (MC, methyl cellulose), ethyl cellulose (EC, ethyl cellulose), hydroxyethyl cellulose (HEC) , hydroxyethyl cellulose), hydroxypropyl cellulose (HPC, hydroxypropyl cellulose), methylethyl cellulose (MEC, methylethyl cellulose), hydroxyethylmethyl cellulose (HEMC, hydroxyethylmethyl cellulose), hydroxypropylmethyl cellulose (HPMC, hydroxypropylmethyl cellulose), At least one characterized in that it has a preparation comprising at least one cellulose ether selected from the group of ethylhydroxyethyl cellulose, carboxymethylhydroxyethyl cellulose, and mixtures thereof This is solved by the polymer fiber according to the invention comprising a synthetic thermoplastic polymer.

polymer

The synthetic polymer according to the invention forming the dispersion medium is preferably a thermoplastic polycondensate based on a thermoplastic polymer, in particular a thermoplastic polycondensate, particularly preferably a so-called synthetic biopolymer, particularly preferably a so-called biopolymer. includes

In the present invention, the term "thermoplastic polymer" refers to a plastic that can be deformed (thermoplastic) in a specific temperature range, preferably in the range of 25°C to 350°C. This process is reversible, ie it can be repeated arbitrarily and frequently by cooling and reheating to the molten state, unless overheating initiates so-called pyrolysis of the material. This is the difference between thermoplastic polymers and thermoset plastics and elastomers.

Within the scope of the present invention, the following polymers are preferably understood by the term "thermoplastic polymer":

acrylonitrile ethylene propylene (diene) styrene copolymer, acrylonitrile methacrylate copolymer, acrylonitrile methyl methacrylate copolymer ), acrylonitrile chlorinated polyethylene styrene copolymer, acrylonitrile butadiene styrene copolymer, acrylonitrile ethylene propylene styrene copolymer, aromatic poly ester (aromatic polyester), acrylonitrile styrene acryloester copolymer, butadiene styrene copolymer, cellulose acetate, cellulose acetobutyrate, cellulose acetopro Cypionate (cellulose acetopropionate), hydrated cellulose (hydrated cellulose), carboxymethyl cellulose (carboxymethyl cellulose), cellulose nitrate (cellulose nitrate), cellulose propionate (cellulose propionate), cellulose triacetate (cellulose triacetate), polyvinyl chloride ( polyvinylchloride), ethylene acrylic acid copolymer, ethylene butyl acrylate copolymer acrylate copolymer, ethylene chlorotrifluoroethylene copolymer, ethylene ethylacrylate copolymer, ethylene methacrylate copolymer, ethylene methacrylic acid copolymer, ethylene tetrafluoroethylene copolymer, ethylene vinylalcohol copolymer, ethylene butene copolymer, ethylcellulose, polystyrene, poly Fluoroethylene propylene, methylmethacrylate acrylonitrile butadiene styrene copolymer, methylmethacrylate butadiene styrene copolymer, methylcellulose, poly Amide 11 (polyamide 11), polyamide 12 (polyamide 12), polyamide 46 (polyamide 46), polyamide 6 (polyamide 6), polyamide 6-3-T (polyamide 6-3-T), polyamide 6 -Terephthalic acid copolymer (polyamide 6-terephthalic acid copolymer), polyamide 66 (polyamide 66), polyamide 69 (polyamide 69), polyamide 610 (polyamide 610), polyamide 612 (polyamide 612), polyamide 6I (polyamide) 6I), polyamide MXD 6 (polyamide MXD 6), polyamide PDA-T (polyamide PDA-T), polyamide, polyarylether, polyaryletherketone, polyamide imide, poly Arylamide, polyamino-bis-maleimide, polyarylate, polybutene-1, polybutylacrylate, polybenzimidazole (polybenzimidazole), poly-bis-maleimide (poly-bis-maleimide), polyoxadiazobenzimidazole (polyoxadiazobenzimidazole), polybutylene terephthalate, polycarbonate (polycarbonate), polychlorotrifluoro Ethylene (polychlorotrifluoroethylene), polyethylene (polyethylene), polyestercarbonate (polyestercarbonate), polyaryletherketone (polyaryletherketone), polyetheretherketone (polyetheretherketone), polyetherimide (polyetherimide), polyetherketone (polyetherketone), polyethylene oxide ( polyethylene oxide), polyarylethersulfone, polyethylene terephthalate, polyimide, polyisobutylene, polyisocyanurate, polyimide sulfone, Polymethacrylimide, polymethacrylate, poly-4-methylpentene-1, polyacetal (polyac) etal), polypropylene, polyphenylene oxide, polypropylene oxide, polyphenylene sulfide, polyphenylene sulfone, polystyrene, polysulfone (polysulfone), polytetrafluoroethylene, polyurethane, polyvinylacetate, polyvinylalcohol, polyvinylbutyral, polyvinylchloride, polyvinyl Polyvinylidene chloride, polyvinylidene fluoride, polyvinylfluoride, polyvinylmethylether, polyvinylpyrrolidone, styrene butadiene copolymer ), styrene isoprene copolymer, styrene maleic acid anhydride copolymer, styrene maleic acid anhydride butadiene copolymer, styrene methyl methacrylate copolymer ( styrene methylmethacrylate copolymer, styrene methylstyrene copolymer, styrene acrylonitrile copolymer, vinylchloride ethylene copolymer, vinyl chloride methacrylate copolymer (v inylchloride methacrylate copolymer, vinyl chloride maleic acid anhydride copolymer, vinyl chloride maleimide copolymer, vinyl chloride methylmethacrylate copolymer, vinyl chloride octylacrylic Vinylchloride octylacrylate copolymer, vinylchloride vinylacetate copolymer, vinylchloride vinylidene chloride copolymer, and vinylchloride vinylidene chloride acrylonitrile copolymer acrylonitrile copolymer).

Within the scope of the present invention, the term "thermoplastic polymer" is understood to be a polymer, preferably chemically and/or physically different from the cellulose ether used for its manufacture. The thermoplastic polymer forming the yarn preferably does not include any cellulose ethers.

Particularly suitable are hot melt thermoplastic polymers (Mp≧100° C.) which are very suitable for the production of spun fibers. Suitable hot melt thermoplastic polymers are, for example, polyamides, such as polyhexamethylene adipinamide, polycaprolactam, aromatic or partially aromatic polyamides ("aramids"). ") (polyamides ("aramide")), aliphatic polyamides such as nylon, partially aromatic or fully aromatic polyesters, polyphenylene sulfide (PPS) (polyphenylene sulfide (PPS)), polymers with ether and keto groups, such as polyetherketone (PEK) (polyetherketone (PEK)) and polyether etherketone (PEEK) (polyether etherketone (PEEK)) or polyethylene ) or polyolefins such as polypropylene.

In hot melt thermoplastic polymers, melt-spun polymers are particularly preferred.

Melt-spun polyesters are mainly composed of building blocks derived from aromatic dicarboxylic acids and aliphatic diols. Typical aromatic dicarboxylic acid building blocks are divalent radicals of benzene dicarboxylic acids, in particular terephthalic acid and isophthalic acid; Ordinary diols have 2 to 4 C atoms, where ethylene glycol and/or propane-13-diol are particularly suitable.

Particular preference is given to polyesters having at least 95 mol % polyethylene terephthalate (PET).

These polyesters, in particular polyethylene terephthalate, typically have a molecular weight corresponding to an intrinsic viscosity (IV) of 0.4 to 1.4 (dl/g) measured for a solution in dichloroacetic acid at 25°C.

The term "synthetic polymer" in the present invention refers to a material composed of a raw material of biological origin (renewable raw material). Thus, it is distinguished from conventional petroleum-based materials or plastics such as, for example, polyethylene (PE), polypropylene (PP) and polyvinylchloride (PVC).

According to the invention, particularly preferred synthetic biopolymers are so-called biopolymers comprising repeating units of lactic acid, hydroxybutyric acid, and/or glycolic acid, preferably repeating units of lactic acid and/or glycolic acid, in particular repeating units of lactic acid. It is a thermoplastic polycondensate based on Polylactic acid is particularly preferred in this case.

"Polylactic acid" herein is understood as a polymer constructed of lactic acid units. Such polylactic acid is usually prepared by condensation of lactic acid, but can also be obtained by ring-opening polymerization of lactide under suitable conditions.

According to the invention, particularly suitable polylactic acids are poly(glycolide-co-L-lactide), poly(L-lactide) (poly(L-lactide)) , poly(L-lactide-co-e-caprolactone)(poly(L-lactide-co-e-caprolactone)), poly(L-lactide-co-glycolide)(poly(L-lactide-co) -glycolide)), poly(L-lactide-coD,L-lactide)(poly(L-lactide-co-D,L-lactide)), poly(D,L-lactide-co-glycolide ) (poly(D,L-lactide-co-glycolide)) and poly(dioxanone)). Such polymers are obtained, for example, from the company Boehringer Ingelheim Pharma KG (Germany) under the trade names Resomer ^® GL 903, Resomer ^® L 206 S, Resomer ^® L 207 S, Resomer ^® L 209 S, Resomer ^® L 210, Resomer ^® L 210 S, Resomer® LC 703 S, Resomer ^® LG 824 S, Resomer ^® LG 855 S, Resomer ^® LG 857 S, Resomer ^® LR 704 S, Resomer ^® LR 706 S, Resomer ^® LR 708, It is commercially available as Resomer ^® LR 927 S, Resomer ^® RG 509 S and Resomer ^® X 206 S.

For the purposes of the present invention, particularly advantageous polylactic acids are in particular poly-D-, poly-L-, or poly-D,L-lactic acids.

In a particularly preferred embodiment, the synthetic polymer is a thermoplastic condensate based on lactic acid.

The polylactic acid used according to the invention is at least 500 g/mol, preferably at least 1,000 g/mol, preferably determined by means of gel permeation chromatography or by end-group titration against polystyrene standards with a narrow distribution, in particular a number average molecular weight (Mn) of preferably at least 500 g/mol, preferably at least 1,000 g/mol, particularly preferably at least 5,000 g/mol, expediently at least 10,000 g/mol, in particular at least 25,000 g/mol, determined indicates. On the other hand, the number average is preferably at most 1,000,000 g/mol, expediently at most 500,000 g/mol, more preferably at most 100,000 g/mol, in particular at most 50,000 g/mol. Number-average molecular weights in the range of at least 10,000 g/mol to 500,000 g/mol in the context of the present invention have proven quite particularly successful.

The weight average molecular weight (Mw) of a preferred lactic acid polymer, particularly poly-D-, poly-L-, or poly-D,L-lactic acid, is preferably determined by gel permeation chromatography against a polystyrene standard having a narrow distribution, , preferably in the range from 750 g/mol to 5,000,000 g/mol, preferably in the range from 5,000 g/mol to 1,000,000 g/mol, particularly preferably in the range from 10,000 g/mol to 500,000 g/mol, in particular 30,000 g /mol to 500,000 g/mol, and the polydispersity of these polymers is more preferably in the range from 1.5 to 5.

The inherent viscosity of a particularly suitable lactic acid polymer, in particular poly-D-, poly-L-, or poly-D,L-lactic acid, measured in chloroform at 25° C., 0.1% polymer concentration, is between 0.5 dl/g and 8.0 dl/g, preferably in the range from 0.8 dl/g to 7.0 dl/g, in particular in the range from 1.5 dl/g to 3.2 dl/g.

Further, the intrinsic viscosity of a particularly suitable lactic acid polymer, in particular poly-D-, poly-L-, or poly-D,L-lactic acid, measured in hexafluoro-2-propanol at 30° C., 0.1% polymer concentration, is 1.0 in the range from dl/g to 2.6 dl/g, in particular in the range from 1.3 dl/g to 2.3 dl/g.

Within the scope of the present invention, it is furthermore a polymer, in particular a thermoplastic polymer, having a glass transition temperature of more than 20 °C, more preferably more than 25 °C, preferably more than 30 °C, particularly preferably more than 35 °C and in particular more than 40 °C. is extremely advantageous In view of a fairly particularly preferred embodiment of the invention, the glass transition temperature of the polymer is in the range from 35°C to 55°C, in particular in the range from 40°C to 50°C.

Furthermore, polymers having a melting point of more than 50° C., more preferably of 60° C. or more, preferably more than 150° C., particularly preferably in the range from 160° C. to 210° C., in particular in the range from 175° C. to 195° C. are particularly suitable. .

In this case, the rate temperature and melting point of the polymer were determined by Differential Scanning Calorimetry; or, for short, preferably determined by DSC. In this regard, the following procedure has proven to be quite particularly successful:

performing DSC measurements under nitrogen on a Mettler-Toledo DSC 30S. Preferably, the calibration is performed with indium. The measurement is preferably carried out under dry oxygen-free nitrogen (flow rate: preferably 40 ml/min). Preferably the sample weight is selected from 15 mg to 20 mg. The sample is initially heated from 0° C. to a temperature preferably exceeding the melting point of the polymer to be studied, then cooled to 0° C. and again heated from 0° C. to this temperature at a heating rate of 10° C./min.

Polyesters, especially lactic acid polymers, are quite particularly preferred as thermoplastic polymers.

polymer fiber

The polymeric fibers according to the invention can exist as finite fibers, for example as so-called staple fibers, or as infinite fibers (filaments). For better dispersibility, the fibers are preferably present as staple fibers. The length of the staple fibers in the foregoing is not subject to any fundamental restrictions, but is generally from 1 to 200 mm, preferably from 2 to 120 mm, particularly preferably from 2 to 60 mm. In particular, short fibers can be cut well according to the present invention. A fiber length of 5 mm or less, in particular 4 mm or less, is thereby understood.

The individual titre of the polymer fibers according to the invention, preferably staple fibers, is 0.3 to 30 dtex, preferably 0.5 to 13 dtex. For some applications 0.3 to 3 dtex titers and fiber lengths of <10 mm, in particular <8 mm, particularly preferably <6 mm, particularly preferably <4 mm are particularly suitable.

The polymer fiber according to the invention is preferably produced from a thermoplastic polymer, in particular a thermoplastic organic polymer, particularly preferably a thermoplastic organic polycondensate, by a melt spinning process. In this case, the polymer material is melted in an extruder and processed by a spinneret to form polymer fibers. The polymeric fibers according to the invention generally do not comprise any fibers produced by spinning from solution, in particular by electrospinning.

Polymeric fibers may also exist as bicomponent fibers, wherein the fibers are composed of component A (core) and component B (shell). In a further embodiment, the melting point of the thermoplastic polymer in component A is at least 5° C., preferably at least 10° C. and particularly preferably at least 20° C. higher than the melting point of the thermoplastic polymer in component B. Preferably, the melting point of the thermoplastic polymer in component A is at least 100°C, preferably at least 140°C, particularly preferably at least 150°C.

The thermoplastic polymer used for the bicomponent fiber is the aforementioned polymer.

Ready

The polymer fiber according to the present invention is on the surface, carboxymethyl cellulose (CMC), methyl cellulose (MC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), methylethyl cellulose ( MEC), hydroxyethylmethyl cellulose (HEMC), hydroxypropylmethyl cellulose (HPMC), ethylhydroxyethyl cellulose, carboxymethylhydroxyethyl cellulose, and a formulation comprising one or more cellulose ethers selected from the group of mixtures thereof 0.1 to 20 wt.%, preferably 0.5 to 3 wt.%.

In a preferred embodiment, the formulation is carboxymethyl cellulose (CMC), methyl cellulose (MC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), methylethyl cellulose (MEC), hydroxy containing at least two cellulose ethers selected from the group of hydroxymethyl cellulose (HEMC), hydroxypropylmethyl cellulose (HPMC), ethylhydroxyethyl cellulose, carboxymethylhydroxyethyl cellulose, particularly preferably methyl cellulose (MC) and hydroxypropylmethyl cellulose (HPMC), which are present on the surface of the polymeric fibers according to the invention in an amount of 0.1 to 20 wt.%, preferably 0.5 to 3 wt.%.

The formulations according to the invention cover at least 99%, preferably at least 99.5%, in particular at least 99.9% and particularly preferably 100% of the total surface of the fibers. The coverage of the surface is determined by microscopic methods. The formulations according to the invention are preferably applied exclusively to fibers and not subsequently to textile fabrics made from fibers.

The formulations according to the invention generally have a thickness of 5 to 10 nm on the fibers. The thickness is determined by a microscopic method.

The cellulose ether(s) used according to the invention are, as additives, EU Reg. NO. 231/2012. Substances approved according to Substances of this kind are commercially available, for example, under the name VIVAPUR® or Methocel ^™ .

In a preferred embodiment, the formulation comprises a cellulose ether, but in particular carboxymethyl cellulose (CMC), methyl cellulose (MC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), methyl Ethyl cellulose (MEC), hydroxymethyl cellulose (HEMC), hydroxypropylmethyl cellulose (HPMC), ethylhydroxyethyl cellulose, carboxymethylhydroxyethyl cellulose are preferred, especially methyl cellulose (MC) and hydroxypropylmethyl It is preferably a formulation of cellulose (HPMC), and the gelation temperature is in the range of 35 °C to 90 °C, preferably in the range of 40 °C to 70 °C, especially in the range of 45 °C to 60 °C, particularly preferably in the range of 45 °C to 55 °C. have

The cellulose ether(s) used according to the invention generally have a degree of substitution (number of substituted hydroxyl groups per glucose molecule) in the range from 1.3 to 2.6, preferably from 1.6 to 2.0. The degree of substitution is generally determined by gas chromatography.

Cellulose ether(s) are used according to the invention, but in particular methyl cellulose preferably has a methoxy group fraction of from 26 % to 33 %, in particular from 27 % to 32 %.

The hydroxypropyl cellulose used according to the invention preferably has a fraction of hydroxypropyl groups of at most 5 %.

The hydroxypropyl cellulose used according to the invention preferably has a hydroxypropyl group fraction of 7% to 12%.

Cellulose ether(s) are used according to the invention, but in particular methyl cellulose preferably has a fraction of hydroxypropyl groups of 26% to 33%, in particular 27% to 32% and at most 5%.

The cellulose ether(s) used according to the invention, but in particular hydroxypropyl cellulose, preferably has a methoxyl group fraction of 26 % to 33 %, in particular 27 % to 32 % and a hydroxy group propyl of 7 % to 12 %. has a fraction.

The cellulose ether(s) used according to the invention usually have an average molecular weight Mn of 10,000 to 380,000 g/mol, preferably 10,000 to 200,000 g/mol, in particular 10,000 to 100,000 g/mol, particularly preferably 12,000 to 60,000 g /mol, particularly preferably from 12,000 to 40,000 g/mol. The average molecular weight Mn is usually determined by gel permeation chromatography (GPC).

The cellulose ether(s) used according to the invention generally have a degree of polymerization of 50 to 1000.

The cellulose ether(s) used according to the invention generally have a viscosity of 10 to 40 mPas, e.g. by Brookfield LVT at 20 °C (30 s after activation of the solution (rest), further 2 wt. % solution.

The formulations according to the invention are generally applied as aqueous formulations, the solids content of the cellulose ether(s) being from 0.1 to 5.0 g/l. Aqueous formulations may also contain additional ingredients such as antifoams and the like.

The polymer fiber finished according to the present invention exhibits very good dispersibility of the fiber in water.

On the one hand, the fibers according to the invention disperse very quickly and remain dispersed for a relatively long time, on the other hand, the polymer fibers finished according to the invention also demonstrate good storage stability, ie even after storage of the fibers. The fibers produced according to the present invention can be easily dispersed even after storage for at least one month (at room temperature 25° C. and in the range of 20 to 70% relative moisture), and exist very evenly distributed in the form of dispersed fibers. The polymeric fibers finished according to the invention are also suitable for stabilization of aqueous dispersions, wherein in addition to the fibers according to the invention solid particulate particles, for example mineral particles, are additionally present. The titre of the polymeric fibers is determined in this embodiment for polymeric fibers having a fiber length of 0.3 to 3 dtex and less than 10 mm, in particular less than 8 mm, particularly preferably less than 6 mm, particularly preferably less than 4 mm. Suitable.

The polymer fiber finished according to the present invention also stabilizes the aqueous dispersion with other polymer fibers not finished according to the present invention. The other polymeric fibers may be different or identical with respect to the fiber-forming polymer, and these other polymeric fibers may not be finished in accordance with the present invention. The fibers according to the invention may therefore be very suitable for use in the production of wetted fabrics. The addition of the polymer fibers finished according to the present invention may be performed in a pulper or a sheet former.

Polymeric fibers having a titre of 0.3 to 3 dtex and a fiber length of less than 10 mm, in particular less than 8 mm, particularly preferably less than 6 mm, particularly preferably less than 4 mm are suitable for this embodiment.

The synthetic polymer fiber according to the present invention is produced by a conventional method. If necessary, the synthetic polymer is first dried and fed into the extruder. The molten material is then spun by conventional apparatus with suitable corresponding dies. The exit velocity in the die exit area matches the spinning velocity, resulting in a fiber with the desired titre. The spinning rate is understood to be the rate at which the coagulated yarn is removed. The yarn removed in this way can be fed directly to drawing, or it can also be wound up and stored and drawn at a later time. Fibers and filaments drawn in a conventional manner may generally be fixed by conventional methods and cut to a desired length to form staple fibers. In this case, the fibers may or may not be crimped, and in the case of the crimped version the crimping should be configured for the wet laying method (low crimping).

The formed fibers may have circular, elliptical and other suitable cross-sections, or other shapes such as dumbbell-shaped, elongated, triangular, or trilobed or multilobed cross-sections. Hollow fibers are also possible. Fibers formed from two or more polymers may also be used.

The fiber filaments thus produced are combined to form a yarn, which in turn forms a tow. The tow initially accumulates in the can for further processing. A large tow is prepared by taking the tow stored in the can in the middle. Large tows, which typically exhibit 10-600 ktex, can then be drawn on a conveyor line using conventional methods, preferably at an entry speed of 10 to 110 m/min. Agents that promote stretching but do not adversely affect subsequent properties can be applied here.

The draw ratio preferably extends from 1.25 to 4, in particular from 2.5 to 3.5. The temperature during stretching is within the range of the glass transition temperature of the tow to be stretched, and in the case of polyester, it is, for example, 40°C to 80°C.

Stretching may be performed in a single-step or, if desired, using a two-step drawing process (see, eg, US Pat. No. 3,816,486 in this regard). One or more dressings may be applied prior to and during stretching using conventional methods.

For the crimping/texturing of the drawn fibers to be optionally carried out, it is possible to use the customary method of mechanical crimping using crimping machines known per se. Mechanical for crimping steam-assisted fibers such as stuffer boxes device is preferred. However, fibers crimped by other methods can also be used, so for example three-dimensional crimped fibers can be used. To carry out crimping, the tow is initially tempered to a temperature usually in the range from 50°C to 100°C, preferably from 70°C to 85°C, particularly preferably about 78°C, and from 1.0 to 6.0 bar, particularly preferably is a tow run-in roller pressure of about 2.0 bar, from 0.5 to 6.0 bar, particularly preferably from 1.5 to 6.0 bar with steam of 1.0 to 2.0 kg/min, particularly preferably 1.5 kg/min Treat with a pressure in the stuffer box of 3.0 bar.

If crimping is provided, the formulation according to the invention is applied a second time after stretching and before the crimping machine. The formulations according to the invention are generally heated and applied to the fibers at an application temperature in the range from 30 to 110° C. and dried.

It has been found that drying of the formulation according to the invention and all post-treatment of the fibers fitted with the formulation according to the invention are carried out at a temperature of at least 120° C. This is because higher temperatures adversely affect the dispersibility of the fibers. A very homogeneous and uniform preparation application is achieved at a temperature of at least 120° C. and practically no precipitation is observed. This application is advantageous with the dispersibility according to the invention.

Smooth or selectively crimped fibers relax and/or set in a furnace or hot air, which occurs at a temperature of at least 130° C., since higher temperatures adversely affect the dispersibility of the fibers. to be. The homogeneous and uniform application of the formulation first obtained at temperatures above 130° C. is impaired and the dispersibility according to the invention is reduced.

To produce staple fibers, the flat or optionally crimped fibers are taken, then cut and optionally cured and placed into compression bales as flocks. The staple fibers of the present invention are preferably cut on a mechanical cutting device downstream of the winding. To make the tow type, cutting can be omitted. These tow types are placed in bales in their uncut form and compressed.

In a crimped embodiment the fibers produced according to the invention are preferably at least 2 per cm, preferably at least 3 crimps (crimp arc), preferably from 3 arcs/cm to 9.8 arcs/cm, and particularly preferably represents a crimping degree of 3.9 arcs/cm to 8.9 arcs/cm. In applications for producing textile surfaces, values for crimp degrees of about 5 to 5.5 arcs/cm are particularly preferred. In order to produce a textile surface by a wet-laying method, the degree of crimping must be individually adjusted.

The above parameters spinning speed, stretching, stretching ratio, stretching temperature, setting, setting temperature, run-in rate, crimping/texturing, etc. are determined according to each polymer forming the dispersion medium. These are parameters that the person skilled in the art selects within the usual range.

It is possible to produce textile fabrics from the fibers according to the invention, which is also the subject of the invention. As a result of the good dispersibility of the fibers according to the invention, such textile fabrics are preferably produced by a wet-laid method.

In addition to the improved dispersibility of the fibers in water, the polymer fibers according to the present invention also exhibit good pump transport properties of the fibers dispersed in water, so that the polymer fibers according to the present invention can be used for textile fabrics using the wet laying method. It is particularly suitable for manufacturing. Since the fibers according to the invention promote the dispersibility of solid particulate particles, for example mineral particles, it is also possible to produce textile fabrics with a mineral finish. Polymeric fibers according to the invention having a titer of 0.3 to 3 dtes and a fiber length of <10 mm, in particular <8 mm, particularly preferably <6 mm, particularly preferably <4 mm, are suitable for this embodiment.

In addition to these wet laying methods, so-called melt-blowing methods (eg, "Complete Texile Glossary, Celanese Acetate LLC, 2000" or "Chemiefaser-Lexikon, Robert Bauer, 10th edition, 1993") as described in) are also suitable. This method of melt blowing is suitable, for example, for the production of fine-titer fibers or nonwovens for applications in the field of hygiene.

Therefore, the term "textile fabric" is to be understood in its broadest sense in the context of the present specification. It can include all structures containing fibers according to the invention produced by surface-forming techniques. Examples of such textile fabrics are nonwovens, in particular wetted nonwovens, based on staple fibers or nonwovens, preferably produced by the melt-blowing method.

The fibers according to the invention are characterized by a significant improvement in the persistence of dispersibility compared to fibers without the additives according to the invention. The fibers according to the invention, in the form of veils or similar structures, have very good dispersibility even after relatively long storage periods, for example weeks or months. In addition, the fibers according to the invention have improved long-term dispersion, i.e., in a state in which the fibers are dispersed in a liquid medium, for example water, the fibers remain dispersed for a longer time and begin to settle after a relatively long time.

In addition, the fibers according to the invention exhibit a reduced fiber fly, which improves the working stability as the product significantly increases the grip of the fiber composite. Reduced fiber flight is particularly important for forming textile fabrics, for example nonwovens.

The fabrics produced by the fibers according to the invention are in particular wet fabrics, in particular wet fabrics.

The fabric produced by the fiber according to the invention contains the polymer according to the invention, on its surface 0.1 to 20 wt.%, preferably 0.5 to 3 wt.% of a formulation is applied, the formulation being carboxymethyl Cellulose (CMC), Methyl Cellulose (MC), Ethyl Cellulose (EC), Hydroxyethyl Cellulose (HEC), Hydroxypropyl Cellulose (HPC), Methylethyl Cellulose (MEC), Hydroxyethylmethyl Cellulose (HEMC) , at least one cellulose ether selected from the group of hydroxypropylmethyl cellulose (HPMC), ethylhydroxyethyl cellulose, carboxymethylhydroxyethyl cellulose and mixtures thereof. The proportion of the polymer fibers according to the invention in the textile fabric is generally 10 wt. % or more, preferably 20 wt. % or more, in particular at least 30 wt.%, particularly preferably at least 50 wt. % or more In a particularly preferred embodiment, the fabric consists exclusively of polymer fibers according to the invention.

Test Methods:

The following measurement and test methods are used unless otherwise noted in the above description.

Titer:

The titre was determined according to DIN EN ISO1973.

Dispersibility:

To evaluate the dispersibility, the following test method has been developed and used in accordance with the present invention. The fibers according to the invention are cut to a length of 2-12 mm. The cut fibers are introduced into a glass container (dimensions: length 150 mm; width 200 mm; height 200 mm) at room temperature (25° C.) and filled with demineralized water (denormalization = complete desalination). The amount of fiber is 0.25 g per liter of desalination allowance. For improved evaluation, 1 g fiber and 4 liters of demineralized water are commonly used.

The fiber/unchlorinated water mixture was then stirred (rotational speed in the range of 750-1500 rpm) for at least 3 minutes using a conventional laboratory magnetic stirrer (e.g. IKAMAGRCT) and magnetic stirrer bar (80 mm) and the stirring device was turned on. turn off It is then evaluated whether all fibers are dispersed.

The dispersion behavior of the fibers was evaluated as follows:

not distributed (-)

Partially distributed (o)

Fully Distributed (+)

The evaluation was performed after a defined time interval.

The formulations according to the invention are not included, but otherwise the same fibers are used as a comparison.

Gelation temperature:

The gelation temperature was determined by an oscillation rheometer from Anton Paar, model Physica MCR 301.

The following other parameters, which are not yet specified in the above description, are measured by a measurement or test method according to the document “Methylcellulose, a Cellulose Derivative with Original Physical Properties and Extended Applications” of Polymer 2015, 7(5), 777-803. became

The invention is illustrated by the following examples, which are not limited in scope.

Yes

During processing on a conveyor line, a methyl cellulose solution was applied to the melt-spun PLA fibers and then dried. The resulting PLA fiber thus has a formulation comprising at least one methyl cellulose (MC) on its surface.

The raw PLA fiber contains the formulation according to the present invention on at least 99% of the entire surface of the fiber.

PLA fibers according to the present invention were cut to a length of 6 mm, and 1 g of the cut PLA fibers were dispersed and tested at room temperature (25° C.) as previously described.

For comparison, 1 g PLA fibers did not contain additives according to the invention, but were dispersed and evaluated at room temperature (25° C.) as described above.

The fibers according to the invention, in contrast to the comparative fibers (without the finish according to the invention), demonstrate a much improved long-term dispersion after several weeks of storage, and a much improved permanence of dispersibility.

Claims (25)

A polymer fiber comprising one or more synthetic polymers, wherein the fiber is on the surface, carboxymethyl cellulose (CMC), methyl cellulose (MC), ethyl cellulose (EC), hydride hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), methylethyl cellulose (MEC), hydroxyethylmethyl cellulose (HEMC), hydroxypropyl Preparation comprising at least one cellulose ether selected from the group of methyl cellulose (hydroxypropylmethyl cellulose (HPMC)), ethylhydroxyethyl cellulose, carboxymethylhydroxyethyl cellulose, and mixtures thereof ), wherein the cellulose ether has a gelation temperature in the range of 35°C to 90°C and the formulation covers at least 99% of the total surface of the fiber.
According to claim 1,
A polymer fiber, characterized in that the synthetic polymer is a thermoplastic polymer, a thermoplastic polycondensate, or a thermoplastic polycondensate based on a biopolymer. According to claim 1,
Synthetic polymer is acrylonitrile ethylene propylene (diene) styrene copolymer, acrylonitrile methacrylate copolymer, acrylonitrile methyl methacrylate copolymer methyl methacrylate copolymer, acrylonitrile chlorinated polyethylene styrene copolymer, acrylonitrile butadiene styrene copolymer, acrylonitrile ethylene propylene styrene copolymer , aromatic polyester, acrylonitrile styrene acryloester copolymer, butadiene styrene copolymer, cellulose acetate, cellulose acetobutyrate, Cellulose acetopropionate, hydrated cellulose, carboxymethyl cellulose, cellulose nitrate, cellulose propionate, cellulose triacetate, poly Vinyl chloride (polyvinylchloride), ethylene acrylic acid copolymer (ethylene acrylic acid copolymer), ethylene butyl acrylate copolymer (ethylene b) utylacrylate copolymer, ethylene chlorotrifluoroethylene copolymer, ethylene ethylacrylate copolymer, ethylene methacrylate copolymer, ethylene methacrylic acid acid copolymer, ethylene tetrafluoroethylene copolymer, ethylene vinylalcohol copolymer, ethylene butene copolymer, ethylcellulose, polystyrene, poly Fluoroethylene propylene, methylmethacrylate acrylonitrile butadiene styrene copolymer, methylmethacrylate butadiene styrene copolymer, methylcellulose, poly Amide 11 (polyamide 11), polyamide 12 (polyamide 12), polyamide 46 (polyamide 46), polyamide 6 (polyamide 6), polyamide 6-3-T (polyamide 6-3-T), polyamide 6 -Terephthalic acid copolymer (polyamide 6-terephthalic acid copolymer), polyamide 66 (polyamide 66), polyamide 69 (polyamide 69), polyamide 610 (polyamide 610), polyamide 612 (polyamide 612), polyamide 6I (polyamide) 6I), polyamide MXD 6 (polyamide MXD 6), polyamide PDA-T (polyamide PDA-T), polyamide, polyarylether, polyaryletherketone, polyamide imide, poly Arylamide, polyamino-bis-maleimide, polyarylate, polybutene-1, polybutylacrylate, polybenzimidazole (polybenzimidazole), poly-bis-maleimide (poly-bis-maleimide), polyoxadiazobenzimidazole (polyoxadiazobenzimidazole), polybutylene terephthalate, polycarbonate (polycarbonate), polychlorotrifluoro Ethylene (polychlorotrifluoroethylene), polyethylene (polyethylene), polyestercarbonate (polyestercarbonate), polyaryletherketone (polyaryletherketone), polyetheretherketone (polyetheretherketone), polyetherimide (polyetherimide), polyetherketone (polyetherketone), polyethylene oxide ( polyethylene oxide), polyarylethersulfone, polyethylene terephthalate, polyimide, polyisobutylene, polyisocyanurate, polyimide sulfone, Polymethacrylimide, polymethacrylate, poly-4-methylpentene-1, polyacetal (polyacetal), polypropylene, polyphenylene oxide, polypropylene oxide, polyphenylene sulfide, polyphenylene sulfone, polystyrene, Polysulfone, polytetrafluoroethylene, polyurethane, polyvinylacetate, polyvinylalcohol, polyvinylbutyral, polyvinylchloride, Polyvinylidene chloride, polyvinylidene fluoride, polyvinylfluoride, polyvinylmethylether, polyvinylpyrrolidone, styrene butadiene copolymer (styrene) butadiene copolymer, styrene isoprene copolymer, styrene maleic acid anhydride copolymer, styrene maleic acid anhydride butadiene copolymer, styrene methyl methacrylate copolymer styrene methylmethacrylate copolymer, styrene methylstyrene copolymer, styrene acrylonitrile copolymer, vinylchloride ethylene copolymer, vinyl chloride methacrylate copolymer (vi nylchloride methacrylate copolymer, vinyl chloride maleic acid anhydride copolymer, vinyl chloride maleimide copolymer, vinyl chloride methylmethacrylate copolymer, vinyl chloride octylacrylic copolymer Vinylchloride octylacrylate copolymer, vinylchloride vinylacetate copolymer, vinylchloride vinylidene chloride copolymer, and vinylchloride vinylidene chloride acrylonitrile Polymer fiber, characterized in that it is selected from the group of polymers containing copolymer). According to claim 1,
Polymer fiber, characterized in that the synthetic polymer is polyester. According to claim 1,
A polymer fiber, characterized in that the synthetic polymer is a synthetic biopolymer or a synthetic biopolymer from polylactic acid. 6. The method of claim 5,
Polylactic acid polymer fiber, characterized in that it has a number average molecular weight (Mn) of 500 g / mol or more, 1,000 g / mol or more, 5,000 g / mol or more, 10,000 g / mol or more, or 25,000 g / mol or more. 7. The method of claim 5 or 6,
A polymer fiber, characterized in that the polylactic acid has a number average molecular weight (Mn) of at most 1,000,000 g/mol, at most 500,000 g/mol, at most 100,000 g/mol, or at most 50,000 g/mol. 7. The method of claim 5 or 6,
The polylactic acid has a weight average molecular weight (Mw) ranging from 750 g/mol to 5,000,000 g/mol, from 5,000 g/mol to 1,000,000 g/mol, from 10,000 g/mol to 500,000 g/mol, or from 30,000 g/mol to 500,000 g/mol. ), characterized in that it has a polymer fiber. 7. The method of claim 5 or 6,
Polymeric fiber, characterized in that the polylactic acid has a polydispersity in the range of 1.5 to 5. 7. The method of claim 5 or 6,
Polymeric fiber, characterized in that the polylactic acid is poly-D-, poly-L- or poly-D,L-lactic acid. 6. The method according to any one of claims 1 to 5,
Polymeric fibers, characterized in that the fibers are in the form of staple fibers or staple fibers having a length in the range of 1 to 200 mm. 6. The method according to any one of claims 1 to 5,
A polymer fiber, characterized in that the fiber has a titre of between 0.3 and 30 dtex, or between 0.5 and 13 dtex. 6. The method according to any one of claims 1 to 5,
wherein the fiber is a bicomponent fiber, wherein the fiber consists of component A (core) and component B (shell), and wherein the melting point of component A is at least 5°C, at least 10°C, or at least 20°C higher than the melting point of component B; Characterized by polymer fibers. 6. The method according to any one of claims 1 to 5,
A polymer fiber, characterized in that 0.1 to 20% by weight, or 0.5 to 3% by weight of the formulation is applied to the surface of the fiber. 6. The method according to any one of claims 1 to 5,
The formulation is carboxymethyl cellulose (CMC), methyl cellulose (MC, methyl cellulose), ethyl cellulose (EC, ethyl cellulose), hydroxyethyl cellulose (HEC, hydroxyethyl cellulose), hydroxypropyl cellulose (HPC, hydroxypropyl cellulose) ), methylethyl cellulose (MEC, methylethyl cellulose), hydroxyethylmethyl cellulose (HEMC, hydroxyethylmethyl cellulose), hydroxypropylmethyl cellulose (HPMC, hydroxypropylmethyl cellulose), ethylhydroxyethyl cellulose, carboxymethyl hydroxy It contains two or more cellulose ethers selected from the group of ethyl cellulose (carboxymethylhydroxyethyl cellulose), or the formulation is a formulation from methyl cellulose (MC, methyl cellulose) and hydroxypropylmethyl cellulose (HPMC, hydroxypropylmethyl cellulose) polymer fiber. 6. The method according to any one of claims 1 to 5,
A polymeric fiber, characterized in that the formulation covers at least 99% of the total surface of the fiber, or at least 99.5%, at least 99.9%, or 100% of the total surface of the fiber. 6. The method according to any one of claims 1 to 5,
Polymeric fibers, characterized in that the formulation has a thickness of 5 to 10 nm. 6. The method according to any one of claims 1 to 5,
A polymer fiber, characterized in that the cellulose ether has a gelation temperature in the range of 40°C to 70°C, 45°C to 60°C, or 45°C to 55°C. 6. The method according to any one of claims 1 to 5,
A polymer fiber, characterized in that the cellulose ether has a degree of substitution (number of substituted hydroxyl groups per glucose molecule) in the range of 1.3 to 2.6 or 1.6 to 2.0. 6. The method according to any one of claims 1 to 5,
A polymer fiber, characterized in that the cellulose ether is methyl cellulose, or methyl cellulose having a methoxy group fraction of 26% to 33% or 27% to 32%. 6. The method according to any one of claims 1 to 5,
A polymer fiber, characterized in that the cellulose ether is hydroxypropylcellulose having a hydroxypropyl group fraction of at most 5% or a hydroxypropyl group fraction of 7% to 12%. 6. The method according to any one of claims 1 to 5,
A polymer fiber, characterized in that the cellulose ether has a fraction of methoxy groups of 26% to 33% or 27% to 32% and a fraction of hydroxypropyl groups of up to 5%. 6. The method according to any one of claims 1 to 5,
A polymer fiber, characterized in that the cellulose ether has a methoxy group fraction of 26% to 33% or 27% to 32% and a hydroxypropyl group fraction of 7% to 12%. A textile fabric containing polymer fibers as defined in any one of claims 1 to 5. An aqueous dispersion containing polymer fibers as defined in any one of claims 1 to 5.