CA2216872C - Production of continuous filament fibers from melamine-formaldehyde condensation products - Google Patents
Production of continuous filament fibers from melamine-formaldehyde condensation products Download PDFInfo
- Publication number
- CA2216872C CA2216872C CA002216872A CA2216872A CA2216872C CA 2216872 C CA2216872 C CA 2216872C CA 002216872 A CA002216872 A CA 002216872A CA 2216872 A CA2216872 A CA 2216872A CA 2216872 C CA2216872 C CA 2216872C
- Authority
- CA
- Canada
- Prior art keywords
- melamine
- precondensate
- formaldehyde
- hydroxy
- alkyl
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G12/00—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen
- C08G12/02—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes
- C08G12/26—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic compounds
- C08G12/30—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic compounds with substituted triazines
- C08G12/32—Melamines
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Textile Engineering (AREA)
- Engineering & Computer Science (AREA)
- Medicinal Chemistry (AREA)
- Organic Chemistry (AREA)
- Polymers & Plastics (AREA)
- Health & Medical Sciences (AREA)
- Artificial Filaments (AREA)
- Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
- Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
- Phenolic Resins Or Amino Resins (AREA)
Abstract
A process is disclosed for producing filaments from a hydroxy- or aminoalkylmelamine-modified melamine/formaldehyde condensation product. The highly concentrated aqueous solution of a melamine/formaldehyde condensation product is filtered, extruded through a spinning nozzle, the extruded threads are dried in a dry shaft by means of hot air, and the dried threads are processed in a tempering furnace at temperatures that rise progressively up to a maximum temperature from 160 to 250 ~C, thus hardening the pre-condensed product.
Description
'~ 0050/45800 CA 02216872 1997-10-20 Production of continuous filament fibers from melamine-formalde-hyde condensation prodùcts 5 The present invention relates to a process for producing continu-ous filament fibers from melamine-formaldehyde (MF) condensation products by spinning a highly concentrated aqueous solution of the MF precondensate, evaporating the water and curing the pre-condensate.
The production of fibers from MF condensation products was first described in DE-B-23 64 091. In this process, the aqueou~ solu-tion of the precondensate is spun into a heated atmosphere in which, at one and the same time, the water evaporates and the 15 precondensate cures. Since the curing process takes a compara-tively long time, long piping is required downstream of the spin-neret if nontacky fibers are to be obtained. In addition, this process gives adequate spinning speeds only if the MF condensate is admixed with fiber-forming polymers, for example polyvinyl al-20 cohol. However, such polymers impair the flame resistance of thefibers and of textile materials produced therefrom.
EP-A-93 965 therefore proposes a~ ing MF precondensates (which may optionally contain N-alkyl-substituted melamines as cocon-25 densed unit~) with from 1 to 20~ by weight of alkali metal salts,preferably sodium metabisulfite, spinning the solution into a heated atmosphere, evaporating the water and curing the precon-densate at elevated temperature. The fibers obtained, however, have in consequence of their alkali metal salt content little hy-30 drolysis resistance.
EP-A-221 330, 408 947 and 523 485 describe hydroxyalkylmelamine-modified MF condensates which can likewise be spun into fibers.
Suitable spinning processes are said to be on the one hand the 35 "dry reaction spinning process" of DE-A-23 64 091 and, on the other, a centrifugal spinning process. However, the latter does not afford continous filament fibers, but only comparatively short fibers of nonuniform length.
40 It is an object of the present invention to provide a technically simple process for producing thin continuous filament fibers from MF condensation products which affords incombustible and infus-ible fibers of high strength and good hydrolysis resistance at high spinning speed.
0~50/45800 CA 02216872 1997-10-20 We have found that this object is achieved by the process of claim 1.
The process of the present invention starts from an MF preconden-5 sate. This MF precondensate comprises as a monomeric building block from 90 to 99.9 mol% of a mixture consisting essentially of (a) from 30 to 99, preferably from 50 to 99, particularly prefer-ably from 85 to 95, mol% of melamine and (b) from 1 to 70, pre-ferably from 1 to 50, particularly preferably from 5 to 15, mol%
10 of a substituted melamine I, or mixtures of substituted melamines I.
A preferred MF precondensate comprises as further monomeric building block (c) from 0.1 to 10 mol%, based on the total number 15 of moles of monomeric building block~ (a) + (b) + (c), of a phe-nol or of a mixture of phenols.
The condensation products of the present invention are obtainable by reacting components (a), (b) and optionally (c) with formalde-20 hyde or formaldehyde-supplying compounds in a molar ratio of me-lamines + phenols to formaldehyde within the range from 1:1.15 to 1:4.5, preferably from 1:1.8 to 1:3Ø
Candidate substituted melamines (b) of the general formula I
X
N ~ N
X~ ~
' N X'' are those in which X, X' and X'' are each selected from the group consisting of -NH2, -NHR and NRR', provided X, X~ and X'~ are not all -NH2, and R and R' are each selected from the group consisting 35 of hydroxy-C2-C1o-alkyl, hydroxy-Ca-C4-alkyl-(oxa-C2-C4-alkyl)n, where n is from 1 to 5, and amino-C2-C12-alkyl.
Preferred hydroxy-C2-C10-alkyl includes hydroxy-C2-C6-alkyl such as 2-hydroxyethyl, 3-hydroxy-n-propyl, 2-hydroxyisopropyl, 40 4-hydroxy-n-butyl, 5-hydroxy-n-pentyl, 6-hydroxy-n-hexyl, 3-hydroxy-2,2-dimethylpropyl, preferably hydroxy-c2-cg-alkyl such as 2-hydroxyethyl, 3-hydroxy-n-propyl, 2-hydroxyisopropyl and 4-hydroxy-n-butyl, particularly preferably 2-hydroxyethyl and 2-hydroxyisopropyl.
Preferred hydroxy-c2-c~-alkyl(oxa-c2-cg-alkyl)n groups are those with n from 1 to 4, preferably those with n = 1 or 2, such as 5-hydroxy-3-oxapentyl, 5-hydroxy-3-oxa-2,5-dimethylpentyl, 5-hy-droxy-3-oxa-1,4-dimethylpentyl, 5-hydroxy-3-oxa-1,2,4,5-5 tetramethylpentyl, 8-hydroxy-3,6-dioxaoctyl.
Amino-C2-C12_alkyl is preferably amino-C2-Cg-alkyl such as 2-aminoethyl, 3-aminopropyl, 4-aminobutyl, 5-aminopentyl, 6-aminohexyl, 7-aminoheptyl and also 8-aminooctyl, particularly 10 preferably 2-aminoethyl and 6-aminohexyl, very particularly pre-ferably 6-aminohexyl.
Substituted melamines particularly suitable for the purposes of the present invention are the following compounds:
15 2-hydroxyethylaminomelamine such as 2-hydroxyethylaminomelamine, 2,4-di(2-hydroxyethylamino)melamine, 2,4,6-Tris(2-hydroxy-ethylamino)melamine, 2-hydroxyisopropylaminomelamine such as 2-(2-hydroxyisopropylamino)melamine, 2,4-di(2-hydroxyisopropyl-amino)melamine, 2,4,6-Tris(2-hydroxyisopropylamino)melamine, ao 5-hydroxy-3-oxapentylaminomelamine such as 2-(5-hydroxy-3-oxa-pentylamino)melamine, 2,4-di(5-hydroxy-3-oxa-pentyl-amino)melamine, 2,4,6-Tris(5-hydroxy-3-oxapentylamino)melamine and also 6-aminohexylaminomelamine such as 2-(6-aminohexylamino-pentylamino)melamine, 2,4-di(6-aminohexylamino)melamine, 25 2,4,6-Tris(6-aminohexylamino)melamine or mixtures thereof, for example a mixture of 10 mol-% of 2-(5-hydroxy-3-oxapentyl-amino)melamine, 50 mol-% 2,4-di(5-hydroxy-3-oxapentyl-amino)melamine and 40 mol-% of 2,4,6-Tris(5-hydroxy-3-oxa-pentylamino)melamine.
Suitable phenols (c) include phenols with one or two hydroxyl groups, such as unsubstituted phenols, phenols substituted by radicals selected from the group consisting of Cl-Cg-alkyl and hy-droxyl, and also Cl-C4-alkanes substituted by two or three phenol 35 groups, di(hydroxyphenyl) sulfones, and mixtures thereof.
Preferred phenols include phenol, 4-methylphenol, 4-tert-butyl-phenol, 4-n-octylphenol, 4-n-nonylphenol, pyrocatechol, resorci-nol, hydroquinone, 2,2-bis(4-hydroxyphenyl)propane, 4,4'-dihy-40 droxydiphenyl sulfone, particularly preferably phenol, resorcinoland 2,2-bis(4-hydroxyphenyl)propane.
Formaldehyde is typically used in the form of an aqueous solution having a concentration of, for example, from 40 to 50% by weight 45 or in the form of compounds that supply formaldehyde in the course of the reaction with (a) and (b), for example as CA 022l6872 l997-l0-20 oligomeric or polymeric formaldehyde in solid form, such as para-formaldehyde, l,3,5-trioxane or 1,3,5,7-tetroxocane.
A preferred MF precondensate is produced using from 1 to 50, pre-5 ferably 5 to 15, in particular from 7 to 12, mol% of the substi-tuted melamine and also from 0.1 to 9.5, preferably from 1 to 5, mol% of one of the above-recited phenols or mixtures thereof.
The precondensate is produced by polycondensing melamine, substi-10 tuted melamine and phenol together with formaldehyde or a formal-dehyde-supplying compound, either by having all components pres-ent from the start or adding them portionwise and gradually to the reaction and subse~uently adding further melamine, substi-tuted melamine or phenol to the precondensates formed.
The polycondensation is typically carried out in a conventional manner (see EP-A-355 760, Houben Weyl, Vol. 14/2, p. 357 ff).
The reaction temperatures used are generally within the range 20 from 20 to 150 c, preferably from 40 to 140 C.
The reaction pressure is typically uncritical. In general, the pressure employed is within the range from 100 to 500 kPa, pre-ferably from 100 to 300 kPa.
as The reaction can be carried out with or without solvent. Typical-ly, no solvent is added when aqueous formaldehyde solution is used. If formaldehyde bound in solid form is used, water is used as solvent, and the amount used is typically within the range 30 from 5 to 40, preferably from 15 to 25, % by weight based on the total amount of monomer used.
Furthermore, the polycondensation is generally carried out within a pH range above 7. Preference is given to the pH range from 7.5 35 to 10.0, particularly preferably from 8 to lO.
Moreover, the reaction mixture may contain small amounts of cus-tomary additives, for example amines and also aminoalcohols such as diethylamine, ethanolamine, diethanolamine or 2-diethylamino-40 ethanol.
Suitable further additives include fillers, for example metalpowders, metal salts or silicates, for example kaolin, talc, ba-ryte, quartz or chalk, and also pigments and dyes.
0050/45800 CA 022l6872 l997-l0-20 The polycondensation can be carried out batchwise or continuous-ly, for example in a stirred tank or in an extruder (see EP-A-355 760).
5 In an advantageous embodiment, first a precondensate solution is prepared in a continuous extruder or kneader and then passed into a heatable stirred tank where it is devolatilized at low viscos-ity and then further condensed to viscosities of 2000-50,000 Pas, preferably 3000-10,000 Pas. However, it is also possible to carry 10 out all the steps of mixing, condensing and devolatilizing in an extruder. It is further possible to prepare the solution com-pletely in a batchwise stirred tank.
The process of the present invention is then carried out in the 15 following successive steps:
A. First the aqueous solution of the precondensate with a water content of from 5 to 40, preferably from 10 to 25, % by weight is filtered, removing coarse particles and impurities.
This can be done using a depth filter, for example.
B The aqueous solution is then forced by means of a pump through a spinneret. This spinneret has from 500 to 5000 holes which each have a diameter from 40 to 400, especially from 50 to 200, ~m. Individual holes are preferably arranged in the form of a ring on a rectangular plate. The pressure drop in the spinneret in the case of hole diameters of 100 ~m, for example, is about 50 bar.
30 C. The individual filaments emerging from the spinneret are bathed for from 0.5 to 60 sec in dry air in a drying shaft.
The air is passed cocurrently to the emerging filaments and it has a temperature within the range from 20 to 200 C, pre-ferably from 50 to 150 C. This measure preferably removes from 10 to 90% of the water present in the filaments, so that their residual water content is less than 10, preferably less than 5, % by weight.
In a preferred embodiment of the present invention, from 0.1 to 3% by weight, based on the precondensate, of a curing cat-alyst are introduced into the drying shaft together with the , air. Preferred curing catalysts include organic acids, for example formic acid, acetic acid, sulfamic acid and amino acids.
0050/45800 CA 022l6872 l997-l0-20 On emerging from the drying cell the filament bundle can be drawn off by means of godets, twisted by means of a twisting nozzle through sideways blowing with air, laid down as a con-tinuous filament material, or cut directly to a certain sta-ple length. This is the point at which, if desired, surfaceauxiliaries, for example antistick agents and silicone oils, can be added.
D. The dried filaments are then treated for from 10 to 200, pre-ferably from 40 to 90, min in a tempering oven. It is essen-tial that the temperature in this oven gradually increase.
This can be achieved for example by successive temperature zones in the oven. In this way the oven can be kept compara-tively short. If desired, a further catalyst can be added to the warm circulating air. The r~xi lm temperature should be from 160 to 250 C, preferably from 200 to 230 C. The precon-densate i6 fully cured, so that nontacky continuous filament fibers are obtained.
20 E. These continuous filament fibers are finally wound up or cut.
The take-off speed can be varied within wide limits. It is customarily within the range from 200 to 250 m.min~1.
The continuous filament fibers produced according to the present 25 invention can be processed into incombustible and infusible wo-vens and nonwovens.
The drawing shows a preferred embodiment of the present inven-tion, the reference numerals of which are explained in the Exam-30 ple which follows.
Example:
The resin is prepared without bubbles in a stirred tank (1). The 35 water content at the start of the reaction is 18%. The viscosityof the resin to be spun is about 9000 Pas/25 C.
The resin is conveyed by a pump (2) and filtered with the aid of depth filters (3) made of metal and forced by means of a further 40 pump (4) through the spinneret orifices (6). The spinneret has 900 holes 100 ~m in diameter. The throughput of resin per hole is 6 g/h.
0050/45800 CA 022l6872 l997-l0-20 In the drying shaft (5) the fibers (8) are dried within 1.5 s by an air stream (7) with an air inlet temperature of 95 C and an air outlet temperature of about 125 C. The take-off speed is 200 m/
min.
The fibers are laid down as continuous filament material, tem-pered in a drying cabinet (9) in four temperature stages (100 C/130 C/160 C/220 C) each 20 min in length, and finally wound up at (10).
The individual fiber has a diameter of 17 ~m, a tenacity of 2.8 cN/dtex and a breaking exten~ion of 32%.
The production of fibers from MF condensation products was first described in DE-B-23 64 091. In this process, the aqueou~ solu-tion of the precondensate is spun into a heated atmosphere in which, at one and the same time, the water evaporates and the 15 precondensate cures. Since the curing process takes a compara-tively long time, long piping is required downstream of the spin-neret if nontacky fibers are to be obtained. In addition, this process gives adequate spinning speeds only if the MF condensate is admixed with fiber-forming polymers, for example polyvinyl al-20 cohol. However, such polymers impair the flame resistance of thefibers and of textile materials produced therefrom.
EP-A-93 965 therefore proposes a~ ing MF precondensates (which may optionally contain N-alkyl-substituted melamines as cocon-25 densed unit~) with from 1 to 20~ by weight of alkali metal salts,preferably sodium metabisulfite, spinning the solution into a heated atmosphere, evaporating the water and curing the precon-densate at elevated temperature. The fibers obtained, however, have in consequence of their alkali metal salt content little hy-30 drolysis resistance.
EP-A-221 330, 408 947 and 523 485 describe hydroxyalkylmelamine-modified MF condensates which can likewise be spun into fibers.
Suitable spinning processes are said to be on the one hand the 35 "dry reaction spinning process" of DE-A-23 64 091 and, on the other, a centrifugal spinning process. However, the latter does not afford continous filament fibers, but only comparatively short fibers of nonuniform length.
40 It is an object of the present invention to provide a technically simple process for producing thin continuous filament fibers from MF condensation products which affords incombustible and infus-ible fibers of high strength and good hydrolysis resistance at high spinning speed.
0~50/45800 CA 02216872 1997-10-20 We have found that this object is achieved by the process of claim 1.
The process of the present invention starts from an MF preconden-5 sate. This MF precondensate comprises as a monomeric building block from 90 to 99.9 mol% of a mixture consisting essentially of (a) from 30 to 99, preferably from 50 to 99, particularly prefer-ably from 85 to 95, mol% of melamine and (b) from 1 to 70, pre-ferably from 1 to 50, particularly preferably from 5 to 15, mol%
10 of a substituted melamine I, or mixtures of substituted melamines I.
A preferred MF precondensate comprises as further monomeric building block (c) from 0.1 to 10 mol%, based on the total number 15 of moles of monomeric building block~ (a) + (b) + (c), of a phe-nol or of a mixture of phenols.
The condensation products of the present invention are obtainable by reacting components (a), (b) and optionally (c) with formalde-20 hyde or formaldehyde-supplying compounds in a molar ratio of me-lamines + phenols to formaldehyde within the range from 1:1.15 to 1:4.5, preferably from 1:1.8 to 1:3Ø
Candidate substituted melamines (b) of the general formula I
X
N ~ N
X~ ~
' N X'' are those in which X, X' and X'' are each selected from the group consisting of -NH2, -NHR and NRR', provided X, X~ and X'~ are not all -NH2, and R and R' are each selected from the group consisting 35 of hydroxy-C2-C1o-alkyl, hydroxy-Ca-C4-alkyl-(oxa-C2-C4-alkyl)n, where n is from 1 to 5, and amino-C2-C12-alkyl.
Preferred hydroxy-C2-C10-alkyl includes hydroxy-C2-C6-alkyl such as 2-hydroxyethyl, 3-hydroxy-n-propyl, 2-hydroxyisopropyl, 40 4-hydroxy-n-butyl, 5-hydroxy-n-pentyl, 6-hydroxy-n-hexyl, 3-hydroxy-2,2-dimethylpropyl, preferably hydroxy-c2-cg-alkyl such as 2-hydroxyethyl, 3-hydroxy-n-propyl, 2-hydroxyisopropyl and 4-hydroxy-n-butyl, particularly preferably 2-hydroxyethyl and 2-hydroxyisopropyl.
Preferred hydroxy-c2-c~-alkyl(oxa-c2-cg-alkyl)n groups are those with n from 1 to 4, preferably those with n = 1 or 2, such as 5-hydroxy-3-oxapentyl, 5-hydroxy-3-oxa-2,5-dimethylpentyl, 5-hy-droxy-3-oxa-1,4-dimethylpentyl, 5-hydroxy-3-oxa-1,2,4,5-5 tetramethylpentyl, 8-hydroxy-3,6-dioxaoctyl.
Amino-C2-C12_alkyl is preferably amino-C2-Cg-alkyl such as 2-aminoethyl, 3-aminopropyl, 4-aminobutyl, 5-aminopentyl, 6-aminohexyl, 7-aminoheptyl and also 8-aminooctyl, particularly 10 preferably 2-aminoethyl and 6-aminohexyl, very particularly pre-ferably 6-aminohexyl.
Substituted melamines particularly suitable for the purposes of the present invention are the following compounds:
15 2-hydroxyethylaminomelamine such as 2-hydroxyethylaminomelamine, 2,4-di(2-hydroxyethylamino)melamine, 2,4,6-Tris(2-hydroxy-ethylamino)melamine, 2-hydroxyisopropylaminomelamine such as 2-(2-hydroxyisopropylamino)melamine, 2,4-di(2-hydroxyisopropyl-amino)melamine, 2,4,6-Tris(2-hydroxyisopropylamino)melamine, ao 5-hydroxy-3-oxapentylaminomelamine such as 2-(5-hydroxy-3-oxa-pentylamino)melamine, 2,4-di(5-hydroxy-3-oxa-pentyl-amino)melamine, 2,4,6-Tris(5-hydroxy-3-oxapentylamino)melamine and also 6-aminohexylaminomelamine such as 2-(6-aminohexylamino-pentylamino)melamine, 2,4-di(6-aminohexylamino)melamine, 25 2,4,6-Tris(6-aminohexylamino)melamine or mixtures thereof, for example a mixture of 10 mol-% of 2-(5-hydroxy-3-oxapentyl-amino)melamine, 50 mol-% 2,4-di(5-hydroxy-3-oxapentyl-amino)melamine and 40 mol-% of 2,4,6-Tris(5-hydroxy-3-oxa-pentylamino)melamine.
Suitable phenols (c) include phenols with one or two hydroxyl groups, such as unsubstituted phenols, phenols substituted by radicals selected from the group consisting of Cl-Cg-alkyl and hy-droxyl, and also Cl-C4-alkanes substituted by two or three phenol 35 groups, di(hydroxyphenyl) sulfones, and mixtures thereof.
Preferred phenols include phenol, 4-methylphenol, 4-tert-butyl-phenol, 4-n-octylphenol, 4-n-nonylphenol, pyrocatechol, resorci-nol, hydroquinone, 2,2-bis(4-hydroxyphenyl)propane, 4,4'-dihy-40 droxydiphenyl sulfone, particularly preferably phenol, resorcinoland 2,2-bis(4-hydroxyphenyl)propane.
Formaldehyde is typically used in the form of an aqueous solution having a concentration of, for example, from 40 to 50% by weight 45 or in the form of compounds that supply formaldehyde in the course of the reaction with (a) and (b), for example as CA 022l6872 l997-l0-20 oligomeric or polymeric formaldehyde in solid form, such as para-formaldehyde, l,3,5-trioxane or 1,3,5,7-tetroxocane.
A preferred MF precondensate is produced using from 1 to 50, pre-5 ferably 5 to 15, in particular from 7 to 12, mol% of the substi-tuted melamine and also from 0.1 to 9.5, preferably from 1 to 5, mol% of one of the above-recited phenols or mixtures thereof.
The precondensate is produced by polycondensing melamine, substi-10 tuted melamine and phenol together with formaldehyde or a formal-dehyde-supplying compound, either by having all components pres-ent from the start or adding them portionwise and gradually to the reaction and subse~uently adding further melamine, substi-tuted melamine or phenol to the precondensates formed.
The polycondensation is typically carried out in a conventional manner (see EP-A-355 760, Houben Weyl, Vol. 14/2, p. 357 ff).
The reaction temperatures used are generally within the range 20 from 20 to 150 c, preferably from 40 to 140 C.
The reaction pressure is typically uncritical. In general, the pressure employed is within the range from 100 to 500 kPa, pre-ferably from 100 to 300 kPa.
as The reaction can be carried out with or without solvent. Typical-ly, no solvent is added when aqueous formaldehyde solution is used. If formaldehyde bound in solid form is used, water is used as solvent, and the amount used is typically within the range 30 from 5 to 40, preferably from 15 to 25, % by weight based on the total amount of monomer used.
Furthermore, the polycondensation is generally carried out within a pH range above 7. Preference is given to the pH range from 7.5 35 to 10.0, particularly preferably from 8 to lO.
Moreover, the reaction mixture may contain small amounts of cus-tomary additives, for example amines and also aminoalcohols such as diethylamine, ethanolamine, diethanolamine or 2-diethylamino-40 ethanol.
Suitable further additives include fillers, for example metalpowders, metal salts or silicates, for example kaolin, talc, ba-ryte, quartz or chalk, and also pigments and dyes.
0050/45800 CA 022l6872 l997-l0-20 The polycondensation can be carried out batchwise or continuous-ly, for example in a stirred tank or in an extruder (see EP-A-355 760).
5 In an advantageous embodiment, first a precondensate solution is prepared in a continuous extruder or kneader and then passed into a heatable stirred tank where it is devolatilized at low viscos-ity and then further condensed to viscosities of 2000-50,000 Pas, preferably 3000-10,000 Pas. However, it is also possible to carry 10 out all the steps of mixing, condensing and devolatilizing in an extruder. It is further possible to prepare the solution com-pletely in a batchwise stirred tank.
The process of the present invention is then carried out in the 15 following successive steps:
A. First the aqueous solution of the precondensate with a water content of from 5 to 40, preferably from 10 to 25, % by weight is filtered, removing coarse particles and impurities.
This can be done using a depth filter, for example.
B The aqueous solution is then forced by means of a pump through a spinneret. This spinneret has from 500 to 5000 holes which each have a diameter from 40 to 400, especially from 50 to 200, ~m. Individual holes are preferably arranged in the form of a ring on a rectangular plate. The pressure drop in the spinneret in the case of hole diameters of 100 ~m, for example, is about 50 bar.
30 C. The individual filaments emerging from the spinneret are bathed for from 0.5 to 60 sec in dry air in a drying shaft.
The air is passed cocurrently to the emerging filaments and it has a temperature within the range from 20 to 200 C, pre-ferably from 50 to 150 C. This measure preferably removes from 10 to 90% of the water present in the filaments, so that their residual water content is less than 10, preferably less than 5, % by weight.
In a preferred embodiment of the present invention, from 0.1 to 3% by weight, based on the precondensate, of a curing cat-alyst are introduced into the drying shaft together with the , air. Preferred curing catalysts include organic acids, for example formic acid, acetic acid, sulfamic acid and amino acids.
0050/45800 CA 022l6872 l997-l0-20 On emerging from the drying cell the filament bundle can be drawn off by means of godets, twisted by means of a twisting nozzle through sideways blowing with air, laid down as a con-tinuous filament material, or cut directly to a certain sta-ple length. This is the point at which, if desired, surfaceauxiliaries, for example antistick agents and silicone oils, can be added.
D. The dried filaments are then treated for from 10 to 200, pre-ferably from 40 to 90, min in a tempering oven. It is essen-tial that the temperature in this oven gradually increase.
This can be achieved for example by successive temperature zones in the oven. In this way the oven can be kept compara-tively short. If desired, a further catalyst can be added to the warm circulating air. The r~xi lm temperature should be from 160 to 250 C, preferably from 200 to 230 C. The precon-densate i6 fully cured, so that nontacky continuous filament fibers are obtained.
20 E. These continuous filament fibers are finally wound up or cut.
The take-off speed can be varied within wide limits. It is customarily within the range from 200 to 250 m.min~1.
The continuous filament fibers produced according to the present 25 invention can be processed into incombustible and infusible wo-vens and nonwovens.
The drawing shows a preferred embodiment of the present inven-tion, the reference numerals of which are explained in the Exam-30 ple which follows.
Example:
The resin is prepared without bubbles in a stirred tank (1). The 35 water content at the start of the reaction is 18%. The viscosityof the resin to be spun is about 9000 Pas/25 C.
The resin is conveyed by a pump (2) and filtered with the aid of depth filters (3) made of metal and forced by means of a further 40 pump (4) through the spinneret orifices (6). The spinneret has 900 holes 100 ~m in diameter. The throughput of resin per hole is 6 g/h.
0050/45800 CA 022l6872 l997-l0-20 In the drying shaft (5) the fibers (8) are dried within 1.5 s by an air stream (7) with an air inlet temperature of 95 C and an air outlet temperature of about 125 C. The take-off speed is 200 m/
min.
The fibers are laid down as continuous filament material, tem-pered in a drying cabinet (9) in four temperature stages (100 C/130 C/160 C/220 C) each 20 min in length, and finally wound up at (10).
The individual fiber has a diameter of 17 ~m, a tenacity of 2.8 cN/dtex and a breaking exten~ion of 32%.
Claims (4)
1. A process for producing continuous filament fiber from condensation products of (a) from 30 to 99 mol% of melamine and (b) from 1 to 70 mol% of a substituted melamine of the general formula I
I
where X, X' and X'' are each selected from the group consisting of -NH2, -NHR and -NRR', and X, X' and X'' are not all -NH2, and R and R' are each selected from the group consisting of hydroxy-C2-C4-alkyl, hydroxy-C2-C4-alkyl-(oxa-C2-C4-alkyl)n, where n is from 1 to 5, and amino-C2-C12-alkyl, or mixtures of melamines I, with formaldehyde or formaldehyde-supplying compounds in a molar ratio of melamines to formaldehyde within the range from 1:1 to 1:4.5 by spinning a highly concentrated aqueous solution of the melamine-formaldehyde precondensate, evaporating the water and curing the precondensate, which comprises the following steps:
A. filtering an aqueous solution of the precondensate with a water content of from 5 to 40% by weight to remove coarse particles and impurities, B. forcing the bubble-free aqueous solution through a spinneret having from 500 to 5000 holes each from 40 to 400 µm in diameter, C. bathing the extruded filaments in a drying shaft with a cocurrent stream of dry hot air at from 20 to 200°C for from 0.5 to 60 sec to reduce the residual water content to less than 10% by weight, D. converging the dried filaments into fiber bundles to treat them in a tempering oven for from 10 to 200 min at temperatures which gradually increase to a maximum temperature within the range from 160 to 250°C and fully cure the precondensate, and E. winding up or cutting the fiber.
I
where X, X' and X'' are each selected from the group consisting of -NH2, -NHR and -NRR', and X, X' and X'' are not all -NH2, and R and R' are each selected from the group consisting of hydroxy-C2-C4-alkyl, hydroxy-C2-C4-alkyl-(oxa-C2-C4-alkyl)n, where n is from 1 to 5, and amino-C2-C12-alkyl, or mixtures of melamines I, with formaldehyde or formaldehyde-supplying compounds in a molar ratio of melamines to formaldehyde within the range from 1:1 to 1:4.5 by spinning a highly concentrated aqueous solution of the melamine-formaldehyde precondensate, evaporating the water and curing the precondensate, which comprises the following steps:
A. filtering an aqueous solution of the precondensate with a water content of from 5 to 40% by weight to remove coarse particles and impurities, B. forcing the bubble-free aqueous solution through a spinneret having from 500 to 5000 holes each from 40 to 400 µm in diameter, C. bathing the extruded filaments in a drying shaft with a cocurrent stream of dry hot air at from 20 to 200°C for from 0.5 to 60 sec to reduce the residual water content to less than 10% by weight, D. converging the dried filaments into fiber bundles to treat them in a tempering oven for from 10 to 200 min at temperatures which gradually increase to a maximum temperature within the range from 160 to 250°C and fully cure the precondensate, and E. winding up or cutting the fiber.
2. A process as claimed in claim 1, wherein the melamine-formaldehyde precondensate (c) contains from 0.1 to 10 mol%, based on a+b+c, of substituted or unsubstituted phenols as cocondensed units.
3. A process as claimed in claim 1, wherein, in stage C, from 0.1 to 3% by weight, based on the precondensate, of a curing catalyst is introduced into the drying shaft together with the air.
4. The use of the fibers and filaments produced as claimed in claim 1 for producing incombustible and infusible wovens and nonwovens.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19515277.8 | 1995-04-26 | ||
| DE19515277A DE19515277A1 (en) | 1995-04-26 | 1995-04-26 | Process for the production of continuous fibers from melamine / formaldehyde condensation products |
| PCT/EP1996/001677 WO1996034133A1 (en) | 1995-04-26 | 1996-04-22 | Process for producing filaments from melamine/formaldehyde condensation products |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2216872A1 CA2216872A1 (en) | 1996-10-31 |
| CA2216872C true CA2216872C (en) | 2003-07-08 |
Family
ID=7760374
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002216872A Expired - Fee Related CA2216872C (en) | 1995-04-26 | 1996-04-22 | Production of continuous filament fibers from melamine-formaldehyde condensation products |
Country Status (10)
| Country | Link |
|---|---|
| EP (1) | EP0822997B1 (en) |
| JP (1) | JPH11504084A (en) |
| KR (1) | KR19990008069A (en) |
| CN (1) | CN1070937C (en) |
| AT (1) | ATE195155T1 (en) |
| CA (1) | CA2216872C (en) |
| DE (2) | DE19515277A1 (en) |
| ES (1) | ES2149476T3 (en) |
| MX (1) | MX9707736A (en) |
| WO (1) | WO1996034133A1 (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE29619737U1 (en) * | 1996-11-13 | 1997-01-09 | Rheinische Filztuchfabrik GmbH, 52222 Stolberg | Press pad with a textile yarn |
| US5830574A (en) * | 1997-04-24 | 1998-11-03 | Basf Corporation | Dyeing articles composed of melamine fiber and cellulose fiber |
| EP1088918A1 (en) * | 1999-09-29 | 2001-04-04 | Basf Corporation | Thermoset/thermoplastic fibers and process for producing the same |
| DE102005013420A1 (en) * | 2005-03-21 | 2006-09-28 | Ami-Agrolinz Melamine International Gmbh | Process for the production of thermoset Feinstfaservliesen with high flame, thermal and sound insulation effect |
| DE102006027760A1 (en) * | 2006-02-23 | 2007-08-30 | Ami-Agrolinz Melamine International Gmbh | New melamine formaldehyde condensation product obtained by a reaction of formaldehyde with melamine derivative, useful as e.g. binding agent in laminates |
| DE102008038943A1 (en) | 2008-08-11 | 2010-02-18 | Borealis Agrolinz Melamine Gmbh | New crosslinkable acrylate resins, useful e.g. to produce crosslinked semi-finished or molded materials for highly stressed parts in automotive, mechanical-, electrical-engineering and electronics, and as crosslinkers in coating resins |
| JP6701733B2 (en) * | 2013-12-20 | 2020-05-27 | 日産化学株式会社 | FIBER, COMPOSITION FOR PRODUCING THE FIBER, AND BIOCOMPATIBLE MATERIAL CONTAINING THE FIBER |
| CN104831373B (en) * | 2015-06-04 | 2017-01-18 | 四川金象赛瑞化工股份有限公司 | Melamine fiber dry spinning method |
| CN107090661A (en) * | 2017-05-22 | 2017-08-25 | 海安国洋机械科技有限公司 | The crush cutting of Self-spraying metallic fiber spreads felt machine |
| CN114622298B (en) * | 2020-12-10 | 2023-08-25 | 中原工学院 | Method for preparing thermosetting melamine fiber through dry spinning |
| CN115467044B (en) * | 2021-06-10 | 2024-06-14 | 中国科学院成都有机化学有限公司 | Preparation method of melamine fiber and obtained melamine fiber |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3216927A1 (en) * | 1982-05-06 | 1983-11-10 | Basf Ag, 6700 Ludwigshafen | METHOD FOR THE PRODUCTION OF THREADS AND FIBERS THAT ARE AT LEAST 80% BY WEIGHT OF MELAMINE FORMALDE HYDROCONDENSATES |
| US4497934A (en) * | 1984-05-02 | 1985-02-05 | American Cyanamid Company | Method for the production of melamine/aldehyde filaments |
| DE4123050A1 (en) * | 1991-07-12 | 1993-01-14 | Basf Ag | MODIFIED MELAMINE FORMALDEHYDE RESINS |
| AT405288B (en) * | 1994-09-21 | 1999-06-25 | Chemie Linz Gmbh | FLAME-RESISTANT, GLASS FIBER-REINFORCED POLYAMIDE RESIN WITH MELAMINE OR MELEM-PHOSPHORIC ACID CONVERSION PRODUCTS AS A FLAME-RETARDANT |
| DE4440491A1 (en) * | 1994-11-12 | 1996-05-15 | Basf Ag | Fire protection blankets made from melamine-formaldehyde resin fibers |
-
1995
- 1995-04-26 DE DE19515277A patent/DE19515277A1/en not_active Withdrawn
-
1996
- 1996-04-22 CN CN96193499A patent/CN1070937C/en not_active Expired - Fee Related
- 1996-04-22 MX MX9707736A patent/MX9707736A/en not_active Application Discontinuation
- 1996-04-22 JP JP8532151A patent/JPH11504084A/en not_active Ceased
- 1996-04-22 EP EP96914971A patent/EP0822997B1/en not_active Expired - Lifetime
- 1996-04-22 AT AT96914971T patent/ATE195155T1/en not_active IP Right Cessation
- 1996-04-22 CA CA002216872A patent/CA2216872C/en not_active Expired - Fee Related
- 1996-04-22 KR KR1019970707593A patent/KR19990008069A/en active IP Right Grant
- 1996-04-22 WO PCT/EP1996/001677 patent/WO1996034133A1/en active IP Right Grant
- 1996-04-22 DE DE59605682T patent/DE59605682D1/en not_active Expired - Fee Related
- 1996-04-22 ES ES96914971T patent/ES2149476T3/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| CN1182461A (en) | 1998-05-20 |
| MX9707736A (en) | 1997-12-31 |
| CA2216872A1 (en) | 1996-10-31 |
| EP0822997B1 (en) | 2000-08-02 |
| JPH11504084A (en) | 1999-04-06 |
| WO1996034133A1 (en) | 1996-10-31 |
| ATE195155T1 (en) | 2000-08-15 |
| EP0822997A1 (en) | 1998-02-11 |
| DE19515277A1 (en) | 1996-10-31 |
| CN1070937C (en) | 2001-09-12 |
| KR19990008069A (en) | 1999-01-25 |
| DE59605682D1 (en) | 2000-09-07 |
| ES2149476T3 (en) | 2000-11-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2216872C (en) | Production of continuous filament fibers from melamine-formaldehyde condensation products | |
| JP3594624B2 (en) | Melamine-formaldehyde polycondensation composition | |
| AU685271B2 (en) | Inherently light- and heat-stabilized polyamides | |
| CA2123177C (en) | Production of fibers by centrifugal spinning | |
| US3716317A (en) | Pack for spinning heterofilament fibers | |
| CN111676528B (en) | Preparation method of melt direct-spun polyester-nylon composite superfine fiber | |
| CA2087167A1 (en) | Amide-imide resin for production of heat resistant fiber | |
| US5716568A (en) | Method for producing polyester bi-component fibers and filaments | |
| US4138445A (en) | Flame retardant fiber | |
| US5916999A (en) | Process for producing filaments from melamine/formaldehyde condensation products | |
| US4110277A (en) | Nylon modified phenolic resin fibers | |
| US5939515A (en) | Modified melamine-formaldehyde resins | |
| US5530031A (en) | Water-insoluble melamine-formaldehyde resins | |
| US20010049421A1 (en) | Thermoset/thermoplastic fibers and process for producing the same | |
| US4361674A (en) | Amino fibres | |
| US6031064A (en) | Condensation products based on triazines and formaldehyde | |
| WO1995004174A1 (en) | A process for preparing wholly aromatic polyamide filaments | |
| CA1050690A (en) | Fire-retardant fiber of aminoplast and polyvinyl alcohol | |
| US5017641A (en) | Preparation of aqueous nonwoven binders of low formaldehyde emission on curing based on urea, formaldehyde and glyoxal | |
| KR100567687B1 (en) | Utilization of Melamine Resin Fibers and Insulating Materials Based on Melamine Resin Fibers and PolyAlkylene Terephthalate Fibers | |
| US20020060012A1 (en) | Use of melamine resin fibers and insulating materials based on melamine resin fibers and polyalkylene terephthalate fibers | |
| US8722779B2 (en) | Thermoplastically processible aminoplastic resin, thermoset microfibre non-wovens, and process and plant for their production | |
| JPS5949330B2 (en) | Flame retardant resin fiber | |
| MXPA00005273A (en) | Utilization of melamine resin fibers and insulating materials based on melamine resin fibers and poly(alkylene terephthalate) fibers |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |