Classifications

• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
  • D01F6/58—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolycondensation products
  • D01F6/76—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolycondensation products from other polycondensation products

Definitions

• the invention relates to continuous filaments according to the preamble of claim 1, which can be produced by melting aminoplast polymers containing oligo- and / or polytriazine ethers, and to a process for their production according to claim 9 and their use according to claim 41.
• continuous filaments are understood to mean filaments which are not subject to any restriction in length and whose length can be regarded as almost infinite in comparison to the cross section.
• a particular disadvantage of the melamine resin fibers described in DE-A 195 15 277 is that the crosslinking of such melamine resins takes place predominantly via dimethylene ether bridges, which have a considerable susceptibility to hydrolysis and thus cause an undesirable water swelling capacity of the fibers in the long term.
• a further disadvantage is that in these processes the curing catalyst for the crosslinking reaction has to be added before the melamine resin solution is spun. This means that the temperature and time parameters must be set and adhered to very precisely before spinning, because otherwise the hardening reaction starts even before thread formation begins.
• DE-C 2 364 091 describes flame-retardant textile fibers which contain a hardened aminotriazine-aldehyde resin.
• the fibers are also obtained by spinning a solution of an aminotriazine-aldehyde precondensate, it being possible for the solution to be spun to contain further components.
• additional components are, for example, fiber-forming aqueous polymers such as cellulose derivatives, polyvinyl alcohol or polyamides and boric acid or borate.
• the solution is spun in a high-temperature atmosphere in which the solvent evaporates and the aminotriazine cures.
• a disadvantage of the process described in DE-C 2 364 091 is that a sufficient spinning speed and elasticity and good mechanical properties of the fibers can only be achieved if the aminotriazine precondensate solution which has been spun additionally contains the fiber-forming polymers mentioned.
• these components have the disadvantage that they have a negative effect on the flame resistance of the fibers, since they have no flame-retardant properties.
• Another disadvantage is the fact that further additives such as boric acid or borates have to be added in order to have a good shelf life. If this is not the case, the aminotriazine precondensate solutions must be kept at temperatures below 40 ° C until they are spun. At higher temperatures, further condensation occurs prematurely and thus an increase in viscosity, which makes spinning impossible.
• the present invention relates to continuous filaments which can be produced by melting aminoplast polymers containing oligo- and / or polytriazine ethers. These filaments are characterized by high dimensional stability, hydrolysis resistance and flame resistance.
• Triazines are understood to mean aromatic nitrogen heterocycles of the empirical formula C 3 H 3 N 3 with three nitrogen atoms in the 6-ring.
• Triazine segments are understood here to mean parts of a network described here derived from the triazines.
• the triazine segments in the oligotriazine ethers are advantageously linked by bridge members to form 4 to 18-core oligotriazine ethers with a linear and / or branched structure.
• the bridge members preferably form at least one of types (I) to (III).
• the terminal nitrogen atoms shown correspond to the nitrogen atoms belonging to the triazine.
• the substituent R 3 in the triazine segments and / or oligotriazine ethers is almost exclusively C 1 -C 18 alkyl.
• the molar ratio of ether groups: triazine segments in the oligotriazine ethers is preferably 1: 2 to 4.5: 1.
• the proportion of the links between the triazine segments through the bridge members -NH-CHR 3 -OR 4 -O-CHR 3 -NH- is 5 to 95 mol%.
• the aminoplast polymers can optionally contain up to 20% by mass of further reactive polymers of the ethylene copolymer type, maleic anhydride copolymers, modified maleic anhydride copolymers, poly (meth) acrylates, polyamides, polyesters and / or contain polyurethanes.
• the aminoplast polymers contain up to 20% by mass of diols of the HO-R 3 -OH type and up to 2% by mass of stabilizers, UV absorbers and / or auxiliaries.
• the aminoplast polymers can be present as a molding compound, for example in the form of cylindrical, lenticular, pastille-shaped or spherical particles with an average diameter of 0.5 to 8 mm.
• the aminoplast polymers contain 4- to 8-core oligotriazine ethers which contain 4 to 8 triazine cycles in the macromolecule or 30 to 300 core polytriazine ethers which have 30 to 300 triazine cycles in the macromolecule.
• the oligo- and polytriazine ethers R 2 H.
• Oligotriazine ethers are understood here as molecules which contain between 4 and 18 triazine cycles in the macromolecule.
• Polytriazine ether refers to molecules that contain more than 18 triazine cycles in the macromolecule.
• Aminoplast polymers which contain mainly oligotriazine ethers or also those which mainly contain polytriazine ethers or also those which contain both oligo- and polytriazine ethers can be used for the production of the continuous filaments.
• the aminoplast polymers contain either mainly oligo- or mainly polytriazine ethers, which may contain triazine ethers with the same or different substituent R 1 .
• Aminoplast polymers with high molecular weights are used for the continuous filaments according to the invention.
• the molar masses are between 1000 and 15000 g / mol, in particular between 6000 and 7000 g / mol.
• the viscosity of the aminoplast polymers is higher, the higher the condensate sizes and thus the molar masses.
• Triazine derivative Melamine, acetoguanamine and / or benzoguanamine are used as the triazine derivative.
• Formaldehyde, acetaldehyde and / or trimethylolacetaldehyde is used as the aldehyde component.
• the molar ratio of triazine derivative: aldehyde is 1: 1 to 1: 5.
• Pre-condensates of melamine and formaldehyde with a molar ratio of melamine: formaldehyde of 1: 2.5 to 1: 3.5 are used in particular.
• the molar ratio of triazine derivative: aldehyde is usually 1: 1 to 1: 5.
• the triazine-aldehyde precondensate obtained is then completely or partially etherified with C 1 -C 18 alcohols, for example with C 1 -C 4 alcohols.
• the C 1 -C 8 -alkyl-oxa-C 1 -C 8 -alkylene-amino-substituted triazine derivatives obtained after the etherification are then partially re-etherified.
• the transetherification takes place with C 4 -C 18 alcohols and / or diols of the HO-R 5 -OH type and / or polyhydric alcohols.
• the molar ratio of the C 1 -C 8 -alkyl-oxa-C 1 -C 8 -alkylene-amino-substituted triazine derivatives / diol and / or bisepoxide is 20: 1 to 1.1: 1.
• the alcohols mostly used for etherification are methanol and / or butanol.
• the alcohols used for the transetherification are butanol, ethylhexanol, octyl alcohol, lauryl alcohol, stearyl alcohol and / or C 5 -C 18 amino alcohols.
• the diols used for the transetherification are polyethylene glycols, polypropylene glycols and / or polytetrahydrofurans with molecular weights of 500 to 5000, esters and / or polyesters of dicarboxylic acids and / or diols with sequences containing siloxane groups.
• the polyhydric alcohols used for the transetherification are glycerol and / or erythritol and / or their mixtures with dihydric alcohols.
• the bisepoxides used for the transetherification are ethylene glycol diglycidyl ether, octanediol diglycidyl ether, hydroquinone diglycidyl ether and / or diphenylol propane diglycidyl ether.
• C 5 -C 18 alcohols in the presence of which the transetherification is carried out, are amyl alcohol, hexenyl alcohol, octyl alcohol and / or stearyl alcohol.
• aminoplast polymers containing oligo- and / or polytriazine ethers are soluble in polar solvents of the type C 1 -C 10 alcohol, dimethylformamide or dimethyl sulfoxide in concentrations of up to about 60% by mass.
• the solubility of the aminoplast polymers in the abovementioned solvents is one of the reasons why conventional thread-forming processes, such as thread spinning from the resin solution which is customary in the case of hydrophilic aminoplast resins, do not make sense here in the case of the aminoplast polymers containing oligo- and / or polytriazine ethers, for economic reasons , because large amounts of the solvents would be released by evaporation during the thread formation process. In addition, the solvents released would rapidly decrease the thread-pulling ability of the aminoplast polymers.
• a decisive criterion for the continuous filaments according to the invention is their production from the aminoplast-polymer melt by a special melt spinning process.
• the aminoplast polymer can be present either as a molding compound or as an aminoplast melt.
• the aminoplast polymer is preferably present as a molding compound. Then it has to be melted for thread production.
• the melting points of the aminoplast polymers are preferably around 70 ° C to 130 ° C, in particular around 80 ° C to 120 ° C.
• the aminoplast polymer is already in the form of a melt.
• the concentration of the aminoplast polymer in the melt is preferably more than 90% by weight.
• the aminoplast melt is preferably processed at a temperature of approximately 70 ° C. to 150 ° C., in particular approximately 80 ° C. to 140 ° C. and a pressure of 0.1 bar to 200 bar, in a spinning device suitable for melt spinning.
• the aminoplast melt is preferably pressed through a nozzle or a family of nozzles, which is arranged at one end of the spinning device, whereby aminoplast melt threads are generated.
• the diameter of the melt threads generated is, depending on the nozzle, preferably approximately 0.1 to 3 mm and the temperature of the melt threads approximately 70 ° C. to 150 ° C., in particular approximately 100 ° C. to 140 ° C.
• the spinning is usually done in a vertical direction from top to bottom. However, it can also be done in any other direction.
• the not yet hardened aminoplast melt threads are advantageously warped with cooling, whereby as Cooling medium can serve any inert gas.
• the ambient air is preferably used; primarily for economic reasons.
• the cold cooling medium is blown into the thread drawing section.
• the blowing can take place both parallel and perpendicular to the thread pulling direction.
• the continuous threads according to the invention are warped until the desired thread diameter is reached.
• the diameter of the threads decreases continuously during the drawing of the melt threads.
• the warping is advantageously carried out up to a thread diameter of 0.01 to 0.5 mm.
• a preparation in particular containing aliphatic hydrocarbons, is advantageously applied to the threads after and / or during warping.
• substances that are surface-active and / or form a protective layer and / or catalyze the curing reaction are dissolved and / or suspended and / or emulsified in the preparation. This leads to a better thread closure and prevents sticking. It also speeds up pre-curing.
• Pre-curing of the aminoplast is preferably carried out after or during the thread-pulling process. This pre-curing is advantageously carried out under the action of curing catalysts.
• the advantage of pre-curing the aminoplast is that a hard outer layer forms around the aminoplast threads, which prevents the individual threads of the fiber strand from sticking together during further processing.
• Hardening catalysts used with preference are gaseous HCl, gaseous HBr, maleic anhydride, acetic acid vapors, formic acid vapors or mixtures of these components.
• the warping and / or the precuring takes place advantageously in a tempered tube or shaft. It is particularly advantageous to bring the surface of the threads or the family of threads into contact with gaseous and / or finely divided liquid and / or solid, in particular in a carrier gas and / or a non-polar solvent, curing catalysts or mixtures of curing catalysts.
• the temperature during pre-curing depends on the throughput speed, the curing catalyst used and its concentration.
• the pre-hardening is carried out by slowly heating the threads kept free of tension to 130 ° C.
• a further advantageous embodiment of the pre-hardening consists in the pre-hardening being carried out with hardeners activated by light.
• the curing catalysts are activated by irradiation with a suitable light source, such as a point light source or a flat radiator.
• the curing catalysts are advantageously introduced into the aminoplast melt in an amount of approximately 0.1 to 2% by weight, in particular approximately 0.5 to 1% by weight, before spinning.
• Such light-activatable hardeners are those which contain sulfonic acid groups substituted as acid generators as well as halogen-substituted triazine derivatives and onium salts.
• the irradiation and thus the start of the activation of the curing catalysts can take place directly after exiting the nozzle.
• the pre-hardened aminoplast threads can be wound up and / or bundled into a strand and / or deposited to form a flat structure.
• the pre-curing is followed by a final curing of the aminoplast threads by increasing the temperature in the absence or presence of at least one curing catalyst.
• the final curing of the aminoplast advantageously takes place at a temperature of approximately 110 ° C. to 250 ° C., in particular a temperature of approximately 160 ° C. to 190 ° C.
• the final curing can take place in a continuous as well as in a discontinuous procedure.
• An advantageous embodiment of the method is the so-called “continuous mode of operation", in which the final temperature is reached by continuously increasing the temperature.
• the final curing is advantageously carried out in a shaft.
• This shaft is divided into different temperature zones and is usually continuously traversed from top to bottom in the vertical direction.
• a further advantageous embodiment of the method is the so-called "discontinuous mode of operation".
• the pre-hardened aminoplast filaments are advantageously cured by means of a discontinuous increase in temperature, that is to say a gradual increase in temperature, for example in a heating cabinet.
• the continuous filaments according to the invention obtained after the final curing advantageously have a round cross section of approximately 0.005 to 0.5 mm, in particular approximately 0.01 to 0.1 mm. on.
• the continuous filaments according to the invention have excellent resistance to hydrolysis.
• the three-dimensional crosslinking in the continuous filaments according to the invention made of aminoplast polymers containing oligo- and / or polytriazine ether is preferably carried out by the formation of hydrolysis-resistant methylene bridges.
• Another advantage of the continuous filaments according to the invention is their high dimensional stability with excellent flame resistance, since the filaments can be produced unexpectedly without the addition of components such as polyvinyl alcohol.
• Such components which often have to be added in the production of conventional aminoplast fibers, also with regard to processability, improve the mechanical properties, but influence the flame resistance in a negative sense.
• thermoplastic processability as is possible with thermoplastic polymers, is not to be expected
• the hitherto known aminoplast resin threads are produced exclusively by spinning from the aminoplast resin solution, with additions usually still being necessary both to ensure sufficient solution stability up to their processing and to achieve a satisfactory spinning speed.
• aminoplast threads according to the invention can be produced starting from an aminoplast melt. It is not necessary to add additives that stabilize the melt or increase the spinning speed.
• thermoplastic processing area enables greater flexibility in the choice of processing conditions, in particular the temperatures.
• the curing catalyst does not have to be in front of the Thread formation process are added, which allows only very limited processing temperature ranges before spinning in the conventional solution spinning processes.
• the continuous filaments according to the invention are very versatile. Possible applications are the production of hydrolysis-resistant and flame-retardant fabrics, knitted fabrics and nonwovens as well as the use as reinforcing material for the production of composite materials.
• the melt thread generated is drawn off at a speed of 120 m / min and wound onto a spool, the circumference of which is 1 m. Due to the distortion that occurs during the spinning process, the thread diameter is reduced to approx. 40 ⁇ m.
• the bundle of threads formed is exposed in a pre-curing chamber for 3 hours at 55 ° C. in a dry N 2 atmosphere, which contains 0.003% HCl gas, and is thereby pre-cured. Subsequently, the thermal curing takes place in a discontinuous procedure by heating the threads in steps of 10 ° C and a dwell time of 2 hours per temperature setting from 60 ° C to 160 ° C. After hardening, stable threads with a round cross-section and a titer of 15 dtex are obtained, whose elongation is approx. 4% and whose fineness-related tensile strength is approx. 9 cN / tex.
• the melt thread generated in this process is drawn off at a speed of 180 m / min and wound onto a spool, the circumference of which is 1 m. Due to the distortion that occurs during the spinning process, the thread diameter is reduced to approx. 27 ⁇ m.
• the bundle of threads formed is placed in a paraffin oil containing 2% calcium stearate and exposed to the radiation of a mercury vapor lamp until the threads show a clear yellow color and are thus precured.
• the curing then takes place by heating the threads inserted in the paraffin bath in steps of 20 ° C. and a residence time of 1 hour per temperature setting from 40 ° C. to 120 ° C.
• the melt thread generated is drawn off at a speed of 600 m / min and, after the nozzle emerges, a preparation consisting of petroleum, which contains 0.2% hexadecylamine hydrochloride and 0.2% HCl, is applied.
• the thread diameter is reduced to approx. 20 ⁇ m.
• the threads generated in this way, kept tension-free, are slowly heated to 80 ° C and thereby pre-hardened.
• the thermal curing is then carried out in a discontinuous mode of operation by heating the threads in steps of 20 ° C. and a dwell time of 1 hour per temperature setting from 80 ° C. to 160 ° C.
• After washing out the paraffin oil with petroleum ether and rinsing for 1 hour with 40 ° C warm, wetting agent-containing water, stable threads with a round cross-section and a titer of 2.7 dtex are obtained, their elongation approx. 12% and their fineness-related tensile strength approx Is 18 cN / tex.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Artificial Filaments (AREA)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

Country Status (2)

Cited By (4)

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• 2002
  • 2002-09-27 DE DE2002146472 patent/DE10246472A1/de not_active Ceased
• 2003
  • 2003-09-04 EP EP03090284A patent/EP1403405A3/fr not_active Ceased

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