US3826712A - Acrylic synthetic paper and method for producing the same acrylic fibers wet spun from a blend of hydrolyzed and unhydrolyzed acrylic polymers having at least 60 % acrylonitriles by weight and paper made from such fibers - Google Patents

Acrylic synthetic paper and method for producing the same acrylic fibers wet spun from a blend of hydrolyzed and unhydrolyzed acrylic polymers having at least 60 % acrylonitriles by weight and paper made from such fibers Download PDF

Info

Publication number
US3826712A
US3826712A US00320763A US32076373A US3826712A US 3826712 A US3826712 A US 3826712A US 00320763 A US00320763 A US 00320763A US 32076373 A US32076373 A US 32076373A US 3826712 A US3826712 A US 3826712A
Authority
US
United States
Prior art keywords
polymer
acrylic
fibers
paper
nitric acid
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 - Lifetime
Application number
US00320763A
Other languages
English (en)
Inventor
T Kobayashi
Y Terada
Y Masuda
H Sato
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Asahi Kasei Corp
Asahi Chemical Industry Co Ltd
Original Assignee
Asahi Chemical Industry Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from JP47006616A external-priority patent/JPS4875871A/ja
Priority claimed from JP47074663A external-priority patent/JPS4930607A/ja
Application filed by Asahi Chemical Industry Co Ltd filed Critical Asahi Chemical Industry Co Ltd
Application granted granted Critical
Publication of US3826712A publication Critical patent/US3826712A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H5/00—Special paper or cardboard not otherwise provided for
    • D21H5/12—Special paper or cardboard not otherwise provided for characterised by the use of special fibrous materials
    • D21H5/20—Special paper or cardboard not otherwise provided for characterised by the use of special fibrous materials of organic non-cellulosic fibres too short for spinning, with or without cellulose fibres
    • D21H5/205—Special paper or cardboard not otherwise provided for characterised by the use of special fibrous materials of organic non-cellulosic fibres too short for spinning, with or without cellulose fibres acrylic fibres
    • 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
    • D01F6/44—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from mixtures of polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds as major constituent with other polymers or low-molecular-weight compounds
    • D01F6/54—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from mixtures of polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds as major constituent with other polymers or low-molecular-weight compounds of polymers of unsaturated nitriles
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/10—Organic non-cellulose fibres
    • D21H13/12—Organic non-cellulose fibres from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H13/18—Polymers of unsaturated acids or derivatives thereof, e.g. polyacrylonitriles

Definitions

  • Acrylic synthetic paper having an improved strength is provided.
  • Acrylic polymer was dissolved and hydrolyzed in a concentrated nitric acid to obtain a polymer with a swelling water content being not more than 200%; the thus hydrolyzed polymer was blended with up to 95% by weight of an unhydrolyzed acrylic polymer having an acrylonitrile content of at least 30% such that the total acrylonitrile content is at least 60% by weight, then the resulting blend was wet spun by nitric acid to obtain acrylic fiber; and further the resultant acrylic fiber was beaten, converted into a paper sheet and then dried to obtain the acrylic synthetic paper with an improved strength.
  • Japanese Patent Publication No. 20757/61 has proposed a method which uses un-collapsed fibers.
  • Japanese Patent Publication No. 2302/64 has proposed a method which uses gelled filaments stretched to reach the first breaking point and Japanese Patent Publication No. 19602/63 has proposed a method which comprises treating acrylic synthetic fibers with a strong mineral acid.
  • strength of acrylic synthetic paper has been improved to some extent.
  • fibrillating ability of the conventional acrylic synthetic fibers has been insutficient in comparison with that of natural pulp, the strength of the obtained acrylic synthetic paper is inferior to that of natural pulp paper.
  • use of paper strength increasing agents or heat press method have been employed for reinforcing adhesive ability.
  • these methods have not been satisfactory from economical and operational viewpoints.
  • acrylic synthetic fibers having highly fibrillating ability can be produced by wet spinning polymer blend consisting of (i) acrylic polymer having not more than 200 weight percent of swelling water content which polymer is obtained by copolymerizing acrylonitrile and hydrophilic ethylene series monomer and (ii) acrylic polymer other than the acrylic polymer mentioned in (i).
  • acrylic synthetic paper having sufficient properties for commercial and practical use can be obtained.
  • acrylic polymer having not more than 200 weight percent of swelling water content can be produced by dissolving and hydrolyzing the acrylic polymer in a concentrated nitric acid, and that acrylic synthetic paper for practical use can be obtained by wet spinning the hydrolyzed polymer and thereafter by mechanically treating, for example beating, the obtained acrylic fiber, thereby easily to produce acrylic synthetic paper having improved strength.
  • the swelling water content of the polymer can be controlled by selecting the hydrolysis condition such as the temperature of nitric acid, the concentration of nitric acid, the dissolving time, etc. Accordingly, the strength of the acrylic syn thetic paper can be optionally controlled.
  • the present invention relates an acrylic synthetic paper and method for producing the same, which method cornprises beating acrylic fiber, converting the beaten fibers into a paper sheet and drying thus obtained sheet.
  • the present invention is characterized by using, as the aforesaid acrylic fiber:
  • (l) acrylic fiber which is obtained by dissolving and hydrolyzing acrylic polymer in a concentrated nitric acid to give acrylic polymer (hereinafter referred to as A polymer) having not more than 200 weight percent of swelling water content; or
  • B polymer acrylic polymer having not more than 200 weight percent of swelling water content obtained by dissolving and hydrolyzing acrylic polymer in a concentrated nitric acid
  • C polymer acrylic polymer (hereinafter referred to as C polymer) other than B polymer; wherein the amount of B based on the total polymers (B+C) being not less than 5 weight percent.
  • FIG. 1 shows the correlation between the temperature of nitric acid and swelling water content of the polymer, when the acrylonitrile polymer (a polymer in Example 1) was dissolved and hydrolyzed in 65% nitric acid.
  • the abscissa shows polymer dissolving time and the ordinate shows swelling water content of the polymer.
  • FIG. 2 shows the correlation between the concentration of nitric acid and the swelling water content of the polymer, when the said acrylonitrile polymer was dissolved and hydrolyzed at 30 C. in a concentrated nitric acid.
  • the abscissa shows polymer dissolving time and the ordinate shows the swelling water content of the polymer.
  • FIG. 1 shows the correlation between the temperature of nitric acid and swelling water content of the polymer, when the acrylonitrile polymer (a polymer in Example 1) was dissolved and hydrolyzed in 65% nitric acid.
  • the abscissa shows polymer dissolving time and the ordinate
  • FIG. 3 shows the infrared absorption spectrum of the acrylonitrile polymer (a polymer).
  • FIG. 4 shows infrared absorption spectrum of the said a polymer after being dissolved and hydrolyzed in 65% nitric acid at 30 C. for 20 hours.
  • the swelling water content of the acrylic polymer is an important key factor.
  • the fibrillating ability of acrylic fiber obtained by wet spinning by nitric acid the acrylic polymer having not more than 200 weight percent of swelling water content is superior, and by using the said fiber there can be obtained acrylic synthetic paper having improved strength for practical and commercial use.
  • percent in the present invention means weight percent.
  • Swelling water content means the ratio of the amount of the water to the weight of the Swelling Water Content (percent) the amount of swelling water in eoagulated product the Weight of dried coagulated product
  • the amount of the swelling water content in coagulated product was measured by the following procedure. The coagulated product was obtained and washed by water. About 1 g. of the sample was taken from thus obtained product containing ample 'Water, dehydrated by Kokusan Superior 1005 Type centrifuge at a rotation of 3500 -r.p.m. for .10 minutes and then the weight (A g.) was carefully measured.
  • the sample was dried for 2 hours by a hot drier maintained at a temperature of 105 C., and the weight (B g.) was measured. Finally, the amount of swelling water is calculated as (A-B) g. The value of B is used also for the dried weight of the coagulated product.
  • the acrylic polymer having not more than 200 weight percent of swelling water content is called as low swelling acrylic polymer and the acrylic polymer having not less than 200 weight percent of swelling water content is called as now-low swelling acrylic polymer.
  • hydrophilic radical group For the preparation of low swelling acrylic polymer by introducing hydrophilic radical group, two methods were known heretofore. The one is to copolymerize acrylonitrile with hydrophilic ethylene series monomer having a group for example sulphonic acid group, carboxylic acid group, amide group, polyethylene glycol group, etc. The other is to introduce amide group and/or carboxylic acid group into the polymer by hydrolyzing in the nitric acid the nitrile group in the acrylic polymer.
  • acrylic polymer is hydrolyzed so that the swelling water content of the polymer becomes less than 200 weight percent.
  • superior acrylic synthetic paper having an improved strength was obtained from the polymer.
  • the hydrolysis of acrylic polymer ' is influenced by the compositon of polymer, the temperature of nitric acid, the concentration of nitric acid, etc.
  • PIG. 1 shows the change of the swelling water content of acrylonitrile polymer (a polymer in Example 1) being dissolved in 65 nitric acid.
  • the abscissa shows the dissolving time of the polymer and the ordinate shows the swelling water content of the polymer. Since the polymer is hydrolyzed in 65% concentrated nitric acid, the swelling water content of the polymer decreases to below 200%, with the increase of dissolving time.
  • the polymer after being hydrolyzed in a concentrated nitric acid gives absorption at 1 680 cmf
  • the absorption is concurrent with the characteristic absorption of amide group. This will indicate the hydrolysis of nitrile group of the polymer to amide group.
  • the hydrolysis rate of the polymer increases, with the increase of the temperature of nitric acid.
  • the time needed to make the swelling water content of the polymer below 200% is approximately 30, 15, and 5 hours at 10, 30, and 50 C., respectively, of the temperature of nitric acid.
  • the temperature of nitric acid can be widely varied, according to the polymer composition and the concentration of nitric acid. Usually a temperature from 0 C. to 70 0, preferably 5 C. to 50 C. is suitable. If a too high temperature above 70 C. is employed, the hydrolysis reaction of acrylic polymer becomes vigorous and control of the reaction becomes difficult, thereby giving acrylic synthetic polymer having poor strength. On the other hand, if a temperature below 0 C. is employed, the hydrolysis reaction rate becomes too small.
  • FIG. 2 shows the increase of the hydrolysis rate of the polymer with the increase of the concentration of nitric acid.
  • the concentration of nitric acid to be employed is preferably from 55 to The concentration of nitric acid employed below 55%, is not desirable, since the solubility of acrylic polymer becomes insufiicient.
  • a O.D. R. is not less than 011.
  • a O.D.R. means the difference, before and after the hydrolysis, of O.D.R. (Optical Density Ratio) of the absorption of the acrylic polymer measured at 1680 GIL-'1 based on methylene absorption at 1460 cmr
  • O.D.R. Optical Density Ratio
  • low swelling acrylic polymer (B polymer) obtained by dissolving and hydrolyzing acrylic polymer in a concentrated nitric acid, and acrylic polymer C polymer) other than said acrylic polymer is blended to obtain a polymer blend, with B polymer being 5 weight percent of the total polymer; and then thus obtamed polymer blend is wet spun by nitric acid.
  • B polymer low swelling acrylic polymer
  • acrylic polymer C polymer acrylic polymer
  • Acrylic fiber according to the present invention should contain at least 60% of polymerized acrylonitrile.
  • Acrylic synthetic paper obtained from acrylic fiber with less than 60% of acrylonitrile is poor in properties, such as hand touch, weather resistance, chemical resistance, electric resistance, etc.
  • polymer having at least 60% of acrylonitrile should be used for A polymer.
  • B polymer and C polymer should be selected so as to make acrylonitrile content in the fiber not less than 60%.
  • Polymerized acrylonitrile content in B polymer should be at least Below 30%, compatibility of B polymer and C polymer is poor and the obtained acrylic fiber is poor in physical properties. Similarly, blending ratio of B polymer to the total polymer should be at least 5%. Below 5%, fibrillating ability of the obtained acrylic fiber is insulficient. Further, acrylonitrilc content of C polymer is preferably at least 60%.
  • the known technique may be applied for producing the starting acrylic polymers.
  • the polymerization reaction is conducted with or without the catalyst in the presence of heat, light or radioactive rays. Either one of solution polymerization, emulsion polymerization, or suspension polymerization can be employed.
  • the starting acrylic polymer can be random polymer, block type polymer or graft type polymer. Among these, solution polymerization in a concentrated nitric acid is especially preferable, wherein polymerization and hydrolysis can be carried out simultaneously.
  • Acrylic fiber according to the invention can optionally contain ethylene series monomer as far as the specified condition of the composition, is satisfied.
  • Examples of the ethylene series monomers are alphasubstituted acrylonitrile such as methacrylonitrile and alpha-chloroacrylonitrile; alkyl (meth)acrylates such as methyl (meth)acrylate and ethyl (meth)acrylate; vinyl esters of unsaturated ketones such as vinyl acetate, methyl vinyl ketone and ethyl vinyl ketone; vinyl ethers such as vinyl methyl ethers; styrene and alkyl derivatives thereof such as methyl styrene; carboxylic acids and salts thereof such as acrylic acid, alpha-chloroacrylic acid, methacrylic acid, itaconic acid and maleic acid; halogenated vinyl such as vinyl chloride, vinyl bromide and vinylidene chloride; vinyl pyridines such as 2-vinyl pyridine and Z-methyl-S-vinyl pyridine; sulphonic acids and salts thereof such as allyl sulphonic acid, me
  • Acrylic polymer in the invention means the polymer which has acrylonitrile as a polymerization ingredient.
  • the method for obtaining acrylic fiber from acrylic polymer is wet spinning by nitric acid and the known technique is applied for the present invention. Namely, a viscous solution obtained by dissolving the polymer in a concentrated nitric acid is coagulated in an aqueous coagulation bath normally containing less than 40% of nitric acid; and then the coagulated filaments are washed with water and thereafter are stretched usually to more than 3 times in hot water, steam, heated air, etc.
  • acrylic fibers which have been dried or undried are subjected to mechanical treatment, such as beating, and then to sheet making treatment and dried to obtain an acrylic synthetic paper.
  • the production of acrylic synthetic paper from acrylic fibers according to the present invention may be carried out in the same manner as that of the conventional nat ural pulp paper. That is, the apparatus and technique for production of paper from natural pulp may also be used as it is in the present invention.
  • the degree of fibrillation of natural pulp can be controlled by the degree of beating
  • the degree of fibrillation of the acrylic fibers used in the present invention can also be controlled by changing the beating conditions such as beating time, beating load, dispersion concentration of fibers, etc. by a beater for paper making.
  • Acrylic synthetic paper of high strength and good quality can be produced from solely acrylic fibers according to the present invention. But sizing agents, fillers and other known additives may be added at the step of heating or sheet making in the present invention as in the production of the conventional natural pulp paper.
  • the fibrillated fibers obtained by beating the acrylic fibers in the present invention can be used as a reinforcing agent by mixing with natural pulp, fibrous organic or inorganic material or nonfibrous organic or inorganic material and making the mixture into a sheet.
  • the strength is conspicuously improved.
  • the content of the acrylic fibers in the obtained sheet-like material can be optionally determined depending upon the desired strength of the sheet-like material, but preferably is l50%..
  • the acrylic fibers of the present invention as a bonding agent, not only the strength of sheet-like material can be improved by its excellent bonding ability, but also the loss of the bonding agent on the paper making wire can be decreased at paper making.
  • the acrylic fibers are dried to cause firm bonding between the fibers or between fibers and other organic or inorganic material, thereby to impart a high strength to the resultant sheet-like material.
  • Examples of the natural pulp, fibrous organic or inorganic materials, non-fibrous organic or inorganic materials used in the present invention are as follows: Natural pulps such as softwood pulp, hardwood pulp, hemp, etc.; regenerated cellulose fibers such as viscose rayon fibers,
  • cuprammonium rayon fibers, acetate fibers, etc. synthetic fibers such as polyvinyl alcohol fibers, polyamide fibers, polyester fibers, polyester ether fibers, polyethylene fibers, polypropylene fibers, non-self bonding acrylic fibers, etc.; polyethylene and polypropylene synthetic pulps; inorganic fibers such as glass fibers, rock fibers, etc.; solid chips having a maximum diameter of 0.5-50 mm., preferably 1-25 mm., e.g., woody chips such as wood powders, wood chips, etc., powdery, granular and flaky resin chips obtained by crushing high molecular resins, mineral chips obtained by crushing natural minerals such as rocks, ores, micas, etc., glass chips obtained by shaping and crushing glass and other metallic chips, carbonaceous chips, etc.
  • synthetic fibers such as polyvinyl alcohol fibers, polyamide fibers, polyester fibers, polyester ether fibers, polyethylene fibers, polypropylene fibers, non-self bonding acrylic fibers, etc
  • the acrylic synthetic paper of the present invention can be obtained by the known shaping method. That is, heating can be carried out by beating machines such as beater, refiner, etc. and paper making can he carried out by paper making machines such as cylinder machine, Fourdrinier machine, etc. or wet non-woven fabric making machines such as hydroformer, jet former.
  • Example 1 Acrylonitrile polymer (a polymer; swelling water content 350%) was dissolved in nitric acid at the temperature and the concentration as shown in Table 1 to obtain viscous solution and then hydrolyzed for a time as shown in the Table 1. Swelling water content of the hydrolyzed polymer was shown in the Table 1. The viscous solution was cooled at C. On the other hand a polymer was dissolved in 65% nitric acid solution at 5 C., thereby substantially avoiding being hydrolyzed, to give unhydrolyzed a polymer.
  • hydrolyzed polymer and unhydrolyzed polymer were blended in a blending weight ratio being 50/50. Then the polymer blend was extruded into 30% aqueous nitric acid solution kept at 5 C., through spinneret. The resultant filaments were washed with water and then were stretched to 5 times in boiling water to obtain filaments with approximately 3 denier.
  • Example 2 Acrylic polymer (b polymer; swelling water content 280%) containing 98% of acrylonitrile and 2% of N,N- dimethyl acryl amide was dissolved in 70% nitric acid kept at 30 C. to obtain viscous solution and the viscous solution was hydrolyzed in nitric acid for hours. The swelling water content was 130% Then the viscous solution was cooled to 5 C.
  • the said hydrolyzed b polymer and unhydrolyzed b polymer were blended with a blending ratio as shown in Table 2. Thereafter, the polymer blend was extruded into 30% aqueous nitric acid solution at 5 C. through spinneret. The resultant filaments were washed with water and then were stretched to 5 times in boiling water to obtain filaments with approximately 3 denier.
  • Example 3 Acrylic polymer (c polymer; swelling water content 160%) containing of acrylonitrile and 15% of acrylic acid was dissolved in 60% aqueous nitric acid solution at 40 C. to obtain viscous solution.
  • the viscous solution was hydrolyzed in nitric acid at 40 C. for 10 hours.
  • the swelling water content was and 1680 cmt- A O.D.R. was 0.83.
  • the said hydrolyzed viscous c polymer solution and unhydrolyzed viscous d polymer solution were blended in a blending ratio being 50/50.
  • the spinning solution of the polymer blend was extruded into 30% aqueous nitric acid solution at -5 C.
  • the resultant filaments were washed with water and then were stretched to 5 times in boiling water to obtain filaments with approximately 3 denier.
  • the resultant fibers in undried state were beaten, formed into paper and dried to obtain paper having basis weight of 40 g./m. Breaking length of the paper was 9.2 km.
  • Control.c polymer in Example 3 was dissolved in 60% aqueous nitric acid solution at -2 C. to obtain the viscous solution.
  • the viscous solution was kept at 2 C. for 10 hours.
  • the swelling water content of the hydrolyzed polymer was and 1680 crnr' A O.D.R. was 0.05. Then, the viscous solution was further cooled at -5 C.
  • Example 3 d polymer in Example 3 was dissolved in 60% aqueous nitric acid solution at 5 C., thereby avoiding hydrolysis.
  • the resultant fibers in undried state was beaten, formed into paper and dried to obtain paper having basis weight of 40 g./m. Breaking length of the paper was 6.4 km.
  • Example 4 Acrylic polymer (e polymer; swelling water content 140%) containing 40% of acrylonitrile and 60% of methoxy polyethylene glycol acrylate (CH CHCO OCH CH OCH was dissolved in 65 aqueous nitric acid solution at 5 C. to obtain viscous solution. The viscous solution was kept at 5 C. for 50 hours for hydrolysis. The swelling water content of the hydrolyzed polymer was 80% and 1680 cm.- A O.D.R. was 1.10.
  • the resultant fibers were dried at 100 C. Then, the dried fibers were beaten, formed into paper and dried to obtain paper having basis weight of about 40 g./m. Breaking length of the paper was 8.4 km.
  • Example 5 Acrylic polymer (g polymer; swelling water content being 370%) containing 90% of acrylonitrile and 10% of methyl acrylate was dissolved in 70% aqueous nitric acid solution at 30 C. to obtain viscous solution. The viscous solutions were kept at 30 C. for 15 hours and 30 hours for hydrolysis and the swelling water content of thus obtained hydrolyzed polymers were 150% and 110%, respectively.
  • the resultant fibers in undried state was beaten, formed into paper and dried to obtain paper having basis weight of 40 g./m. Breaking length of the paper was 7.5 km.
  • Acrylic polymer (h polymer) was prepared by polymerizing acrylonitrile and acryl amide (with ratio being 80/20) in the presence as catalyst of ammonium persulfate, acetyl acetone and ferric nitrate in 65% aqueous nitric acid solution at 25 C. for 25 hours.
  • the swelling water content of the obtained polymer was 110% and O.D.R. at 1680 cm. was 2.20.
  • the polymer was cooled to 5" C.
  • a polymer was dissolved in 65% aqueous nitric acid solution at 5 C. to obtain the viscous solution avoiding thereby hydrolysis.
  • the resultant fibers in undried state was beaten, formed into paper and dried to obtain paper basis weight of approximately 40 g./m. Breaking length of the paper was 6.8 km.
  • Control 2.-Polymer (i polymer) was prepared by polymerizing acrylonitrile and acryl amide (with ratio being 75/25) in the presence as catalyst azobis-isobutyronitrile in dimethyl sulfoxide at 50 C. for 20 hours.
  • the swelling water content of the obtained polymer was 130% and O.D.R. at 1680 cm? was 2.15.
  • the resultant fibers in undried state was beaten, formed into paper and dried to obtain paper having basis weight of about 40 g./m. Breaking length of the paper was 3.6 km.
  • An acrylic fiber of improved fibrillating characteristics prepared by the steps comprising (a) subjecting an acrylic polymer containing up to 60% by weight acrylonitrile to hydrolysis in nitric acid having a concentration weight unhydrolyzed acrylic polymer having an acrylonitrile content of at least 30%; said amount being such that the total acrylonitrile content is at least by weight; and (0) wet spinning the resultant polymer by nitric acid to form a fiber.
  • An acrylic synthetic paper prepared by the steps comprising (a)' subjecting an acrylic polymer containing up to 60% by weight acrylonitrile to hydrolysis in nitric acid having a concentration of at least 55 by weight at a temperature of O C. for a period of time suflicient to reduce the swelling water content to less than 200% by weight; (b) blending the hydrolyzed polymer with an amount of up to by weight unhydrolyzed acrylic polymer having an acrylonitrile content of at least 30%, said amount being such that the total acrylonitrile content is at least 60% by Weight; and (c) wet spinning the resultant polymer by nitric acid to form fibers; (d) beating the thus obtained acrylic fibers; (e) converting the beaten acrylic fibers into a paper sheet and (f) drying the thus obtained sheet.
  • a sheet-like material comprising acrylic synthetic fibers of Claim 3 further comprising at least one additional fibrous or non-fibrous material, the acrylic fiber content being 1-50% by weight.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Paper (AREA)
  • Artificial Filaments (AREA)
US00320763A 1972-01-18 1973-01-03 Acrylic synthetic paper and method for producing the same acrylic fibers wet spun from a blend of hydrolyzed and unhydrolyzed acrylic polymers having at least 60 % acrylonitriles by weight and paper made from such fibers Expired - Lifetime US3826712A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP47006616A JPS4875871A (enrdf_load_stackoverflow) 1972-01-18 1972-01-18
JP47074663A JPS4930607A (enrdf_load_stackoverflow) 1972-07-27 1972-07-27

Publications (1)

Publication Number Publication Date
US3826712A true US3826712A (en) 1974-07-30

Family

ID=26340804

Family Applications (1)

Application Number Title Priority Date Filing Date
US00320763A Expired - Lifetime US3826712A (en) 1972-01-18 1973-01-03 Acrylic synthetic paper and method for producing the same acrylic fibers wet spun from a blend of hydrolyzed and unhydrolyzed acrylic polymers having at least 60 % acrylonitriles by weight and paper made from such fibers

Country Status (4)

Country Link
US (1) US3826712A (enrdf_load_stackoverflow)
FR (1) FR2168504B1 (enrdf_load_stackoverflow)
GB (1) GB1408465A (enrdf_load_stackoverflow)
IT (1) IT981955B (enrdf_load_stackoverflow)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3928496A (en) * 1973-07-19 1975-12-23 Toray Industries Synthetic fiber for paper and method for producing the same
US4038452A (en) * 1975-05-07 1977-07-26 Asahi Kasei Kogyo Kabushiki Kaisha Bulky non-woven fabric
US4392861A (en) * 1980-10-14 1983-07-12 Johnson & Johnson Baby Products Company Two-ply fibrous facing material
US4425126A (en) 1979-12-28 1984-01-10 Johnson & Johnson Baby Products Company Fibrous material and method of making the same using thermoplastic synthetic wood pulp fibers
EP0141146A1 (en) * 1983-09-12 1985-05-15 American Cyanamid Company Reinforced metal substrate
EP0144553A1 (en) * 1983-09-12 1985-06-19 American Cyanamid Company Non-woven activated carbon fabric
EP0199150A1 (en) * 1985-04-23 1986-10-29 American Cyanamid Company Non-woven activated carbon fabric
US4904343A (en) * 1985-04-23 1990-02-27 American Cyanamid Company Non-woven activated carbon fabric
US20050039872A1 (en) * 2003-05-08 2005-02-24 Dynax Corporation High torque capacity wet paper friction member

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2831601C2 (de) * 1977-07-25 1982-12-16 Asahi Kasei Kogyo K.K., Osaka Wildlederartiges Kunstleder mit einer Flordecke aus Acrylfasern, sowie Verfahren zur Herstellung der letzteren
GB2323392B (en) * 1997-03-21 2001-08-22 Courtaulds Fibres Ltd Fibrillated acrylic fibre

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2579451A (en) * 1948-12-31 1951-12-18 Du Pont Polymeric materials
CH339318A (de) * 1955-08-18 1959-06-30 Halbig Paul Ing Dr Verfahren zur Herstellung von Gespinsten aus Acrylnitrilpolymerisaten

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3928496A (en) * 1973-07-19 1975-12-23 Toray Industries Synthetic fiber for paper and method for producing the same
US4038452A (en) * 1975-05-07 1977-07-26 Asahi Kasei Kogyo Kabushiki Kaisha Bulky non-woven fabric
US4425126A (en) 1979-12-28 1984-01-10 Johnson & Johnson Baby Products Company Fibrous material and method of making the same using thermoplastic synthetic wood pulp fibers
US4392861A (en) * 1980-10-14 1983-07-12 Johnson & Johnson Baby Products Company Two-ply fibrous facing material
EP0141146A1 (en) * 1983-09-12 1985-05-15 American Cyanamid Company Reinforced metal substrate
EP0144553A1 (en) * 1983-09-12 1985-06-19 American Cyanamid Company Non-woven activated carbon fabric
EP0199150A1 (en) * 1985-04-23 1986-10-29 American Cyanamid Company Non-woven activated carbon fabric
US4904343A (en) * 1985-04-23 1990-02-27 American Cyanamid Company Non-woven activated carbon fabric
US20050039872A1 (en) * 2003-05-08 2005-02-24 Dynax Corporation High torque capacity wet paper friction member

Also Published As

Publication number Publication date
DE2302077B2 (de) 1977-03-24
FR2168504B1 (enrdf_load_stackoverflow) 1976-04-30
IT981955B (it) 1974-10-10
DE2302077A1 (de) 1973-07-19
GB1408465A (en) 1975-10-01
FR2168504A1 (enrdf_load_stackoverflow) 1973-08-31

Similar Documents

Publication Publication Date Title
US3047455A (en) Paper manufacture from synthetic non-cellulosic fibers
US3047456A (en) Manufacture of paper products from fibers wet spun from polymer blends
US3826712A (en) Acrylic synthetic paper and method for producing the same acrylic fibers wet spun from a blend of hydrolyzed and unhydrolyzed acrylic polymers having at least 60 % acrylonitriles by weight and paper made from such fibers
US3402231A (en) Process for preparing synthetic fibers for paper products
US2277782A (en) Crimping materials containing synthetic textile fibers
US3912581A (en) Non-woven web structures and method for making the same
US3502607A (en) Art of making dyeable polyacrylonitrile products
US4383086A (en) Filaments and fibers of acrylonitrile copolymer mixtures
US3104154A (en) Graft copolymer containing spinnable solution and method for preparing and spinning thereof
US2972560A (en) Method of manufacturing paper
US3269891A (en) Fixing dry strength resin on fibers by alum in the presence of a buffer
US3733386A (en) Process for producing acrylic synthetic fibers improved in the hydrophilicity
US2784135A (en) Process for the manufacture of polyacrylonitrile films and laminates
US4246066A (en) Method for producing fibrous sheet
US3180845A (en) Method of preparing void free fibers from acrylonitrile polymers
US4913870A (en) Process for preparing polyacrylonitrile filaments having high tensile strength and modulus
US3560318A (en) Fibrous pulp containing partially hydrolyzed polyvinyl acetate
US2899351A (en) Thermoplastic paper
US4332749A (en) Process for the production of polyolefine-based fibrids, and the fibrids obtained
US3828014A (en) High shrinkage threads,yarn and fibers from acrylonitrile polymers
US2654671A (en) Paper product and process for its preparation
US4164522A (en) Vinylidene chloride polymer microgel powders and acrylic fibers containing same
CN113832719B (zh) 一种pbt弹力纤维的制备方法
US3098786A (en) Paper making process
US4719150A (en) Monofils and bristles of homopolymers or copolymers of acrylonitrile, and a process for their manufacture