A method of obtaining a hydrophilic polyacrylonitrile fiber
(57) Abstract:The invention relates to the field of finishing and modification of fibrous textile materials in the form of fibers, yarns, fabrics or knitted fabrics and can be used for manufacture of products for sanitary and technical purposes with high moisture absorption. Describes how to obtain hydrophilic polyacrylonitrile fiber by saponification of the original fiber sodium hydroxide solution, wherein the saponified fibers are first treated with 3-7% aqueous solution of calcium chloride within 10-20 min, and then impregnated with a 1-5% aqueous solution of sodium alginate. The technical result is the obtaining of acrylic fiber with high moisture absorption. table 1. The invention relates to the field of finishing and modification of fibrous textile materials in the form of fibers, yarns, fabrics or knitted fabrics and can be used for manufacture of products for sanitary and technical purposes with high moisture absorption.A method of obtaining hydrophilic polyacrylonitrile fiber-based copolymer of Acrylonitrile and methyl methacrylate. High g is. N 6. - S. 8). The disadvantages of this method include the use of non-conventional ternary copolymer, and double, as well as the difficulty of making a precipitation bath.The closest technical solution is the method of processing polyacrylonitrile fibers with sodium hydroxide. The treatment is carried out with 2.5% NaOH solution at a temperature of 95-98oC for 7-8 minutes the Disadvantage of this method is the relatively low moisture absorption (wolf L. A. and other Textile materials with antimicrobial properties. E. I. Textile industry. Domestic production method. - 1985. - N 3. - S. 7-13).The technical result is the obtaining of acrylic fiber with high moisture absorption.The technical result is achieved by the fact that ordinary commodity polyacrylonitrile fiber (ternary copolymer) successively treated with sodium hydroxide solution of a concentration of 3-5% at a temperature of 96-98oC, calcium chloride 3-7% at temperature (20 2)oC and sodium alginate 1-5% at temperature (20 2)oC.Treatment with solutions of calcium chloride and sodium alginate can be performed immediately after saponification of acrylic fiber, the single difference of the claimed method is the sequential processing of aqueous solutions of sodium hydroxide, calcium chloride and sodium alginate, which allows to obtain a fiber with high moisture absorption.In the proposed method sequential processing of aqueous solutions of sodium hydroxide, calcium chloride and sodium alginate leads to unexpected effect of obtaining fibers with high moisture absorption up to 1580%.It is known that the proposed connections are used in various industries and medicine. Calcium chloride (CaCl2) - upon receipt of calcium, for drying of gases and liquids, its solutions are used as a medicinal remedy for allergies and bleeding. Sodium alginate C5H4O2[(OH)2COONa] is a linear copolymer sodium salt D-mouronval and 2-guluronic acids associated 1,4--glucoside links - used in food, pharmaceutical and textile industries, in the manufacture of paper.The use of serial treatment of PAN fibers with aqueous solutions of sodium hydroxide, calcium chloride and sodium alginate to obtain fibers with high moisture absorption in the prior art by the authors was not found.The proposed method for processing PAN fiber is implemented as education is IDA sodium concentration of 3-5% at a temperature of 96-98oC (boiling water bath) for 15-25 minutes Then colout (0,0050,001 m solution of H2SO4) and washed with demineralized water. The processing solution of calcium chloride is carried out at a temperature of (202)oC for 10-20 min, the concentration of CaCl2- 3-7%, the volume of solution 250 ml calcium maintenanced POLYACRYLONITRILE fiber impregnated at a temperature of (202)oC solution of sodium alginate concentration of 1-5% and press management (pressed 150-200%) and dried.Similar technologies can be treated yarn, fabric or knitted fabric. Examples of specific performance and properties of the fibers treated by the proposed method are presented in the table.Table data - mapping POS. 15 (prototype) POS.2-5, 7-10, 12 (proposed method) to confirm the achievement of the technical result, i.e., in comparison with the prototype is a significant increase in moisture absorption upon contact with water: more than 2 times for 10 min (POS. 15 - 362% and POS. 2 - 758%) and more than 4 times for 60 min (POS. 15 -375% and POS.2 - 1580%). Normal (nesomyinae) POLYACRYLONITRILE fiber, treated with a solution of sodium alginate in the proposed conditions, has a moisture absorption 158% (10 min) and 205% (60 min) (Ref. 14), saponified POLYACRYLONITRILE fiber with sodium alginate has vlagopoulos the maximum moisture absorption at a concentration of calcium chloride 3% (Ref. 1): 570% at 10 min and 450% at 60 minutesFiber, processed by the proposed method is promising when creating dressings, manufacture various sanitary and technical water-absorbing means. A method of obtaining a hydrophilic polyacrylonitrile fiber by saponification of the original fiber sodium hydroxide solution, wherein the saponified fibers are first treated with 3 - 7% aqueous solution of calcium chloride for 10 to 20 min, and then impregnated with 1 - 5% aqueous solution of sodium alginate.
FIELD: sanitary and hygienic facilities.
SUBSTANCE: invention relates to technology of manufacturing chemisorption materials for use in municipal hygiene sphere. Method consists in treatment of chemisorption carboxyl-containing material in Na form with 0.5-1.0% aqueous acid solution, e.g. hydrochloric acid solution, at modulus (ratio of weight of chemisorption material to acid solution volume) 1:30 and treatment time 0.5-1.0 h to transfer material into H-form. Chemisorbent is then washed with softened water to pH 5-6, after which material in H-form is treated for 0.5-1.0 h with 0.5-1.0% potassium hydroxide solution, modulus 1:30. At the expiration of treatment time, material is washed with softened water to pH 5.0-6.5. Presence of three-dimensional lattice, both during treatment time of chemisorption material in the form of fibers or nonwoven material and upon use of products from this material, prevents dissolution of polymer in water or in aqueous solution of acid or potassium hydroxide. Owing to filtration, chemisorbent entraps in water heavy metal ions contained therein and water is saturated with potassium ions so that chemisorption material acquires at least 4 mmol/g of carboxyl groups in K-form.
EFFECT: optimized manufacture conditions.
SUBSTANCE: invention relates to technology for preparing sorbents with fibrous structure by using waste of industrial manufacture. Method involves treatment of fibrous matrix from waste of tanning leather chips with polyelectolyte an aqueous solution obtained by alkaline hydrolysis of polyacrylonitrile or copolymer based on thereof. Prepared sorbent shows the improved capacity for extraction of different components from different aqueous media.
EFFECT: improved preparing method, improved and valuable properties of sorbent.
2 cl, 1 tbl, 2 ex
FIELD: polymer materials.
SUBSTANCE: invention relates to manufacture of ion-exchange fibers with special properties, which can be used as sorbent or as a sorbent constituent for cleaning liquid media, largely natural and waste waters. Method consists in performing alkali hydrolysis of polyacrylonitrile fiber in presence of hydrazine at elevated temperature completed by treatment of fiber with active agent causing degradation of chromophore groups of fiber. Alternatively, ion-exchange fiber is manufactured via alkali hydrolysis of polyacrylonitrile fiber in presence of hydrazine at elevated temperature, hydrolysis reaction being effected in concentrated solution of salt of alkali metal with weak acid followed by treatment of fiber with active agent as above.
EFFECT: improved characteristics of fiber at lower consumption of reagents and stabilized manufacturing process to provide ion-exchange fiber with desired number of chelating sorption groups due to appropriate balance of acid and basic groups resulting from hydrolysis.
18 cl, 5 tbl, 16 ex
FIELD: optionally materials.
SUBSTANCE: invention relates to heat-resistant thread manufacture technology and can be utilized in manufacture of special materials for flak jackets, high-pressure containers, and in airplane construction. Thread is made from aromatic heterocyclic polyamide prepared via low-temperature polycondensation of a mixture composed of 25-70 mol % diamine of formula: , where X represents -NH, -S, -O, -N(CH3), and N(C2H5) and Z represents N or C, and 30-75 mol % of p-phenylenediamine with aromatic dicarboxylic acid chloride used in equimolar proportions in organic solvent and in presence of lithium or calcium chloride. Thus prepared solution is molded into water-dimethylacetamide precipitation bath. Thread is rinsed, dried, thermally treated for 10-30 min at 340-360°C, and then is drawn at 230-270°C at heating time 1-3 sec.
EFFECT: improved performance characteristics of thread.
1 tbl, 7 ex
SUBSTANCE: invention relates to technology for preparing and modification of chemical fibers and threads, in particular, to polyvinylidene fluoride (PVDF) fibers and threads. Method for preparing thread with carbine cover involves preliminary impregnation of PVDF thread of diameter 0.07-0.90 mm with dimethylformamide or dimethylsulfoxide for 1-4 h and the following treatment with 15-17% potassium hydroxide solution in n-butanol or n-propanol medium at temperature 60-80°C. Optimal treatment time is 0.5-4 h. Invention provides simplifying technology in preparing PVDF thread with carbine cover of different diameter and possessing higher physical-mechanical indices, among them, unit strength based on simultaneous elimination of highly toxic and highly inflammable substances, using a single-component highly boiling solvent, decreasing the potassium hydroxide concentration and elimination the ultrasonic field using. Invention can be used chemical industry, in particular, in manufacturing filtering and fettling materials and in medicine as suture biocompatible surgery threads showing the enhanced resistance to thrombosis.
EFFECT: improved preparing method, enhanced and valuable properties of cover.
2 cl, 1 tbl, 41 ex
FIELD: polymer materials.
SUBSTANCE: invention relates to technology of fabrication and modification of man-made fibers and threads, in particular poly(vinylidene sulfide) threads, and can be used in chemical industry for manufacture of filter materials and in medicine as novel surgical threads and implants (endoprostheses) showing biological activity and thrombosis resistance. Thread made from poly(vinylidene sulfide) with carbine coating has diameter 0.10-0.15 mm, linear density from 13.81 to 31.09 tex, knot strength 621-640 MPa, and rupture strength 632-648 MPa. Knitted mesh is made from monofilament poly(vinylidene sulfide) thread and its structure is characterized by density 12-13 courses per 1 cm and contains loops from two thread systems with first system parameters: 6/7, 3/2, 4,5, 1/0, 3/2 and second system parameters: 1/0, 2/3, 1,0, 2/3, 1/0, 2/3. Method of manufacturing knitted mesh comprises making indicated knitted material from indicated thread with density 12-13 course/cm and two indicated thread systems, impregnating the mesh with dimethylsulfoxide or dimethylformamide during 1-4 h, and treating it with 15-17% n-butanol or n-propanol solution of potassium hydroxide. Optimal treatment time is 0.5 to 4 h.
EFFECT: improved physico-mechanical characteristics of articles, to which such properties as chemical stability, thrombosis resistance, biocompatibility, catalytic activity are imparted.
4 cl, 1 tbl, 48 ex
FIELD: polymer materials.
SUBSTANCE: invention relates to manufacture of polymer materials and, in particular, micro- and nanofibers showing elevated strength and durability, which can be employed in a variety of technical fields, including their use in various filters. Composition of fine fiber having diameters between 0,001 and 2 μm contains addition or condensation polymer and aromatic-nature resinous additive with molecular weight 500 to 3000, which additive may be disposed on the surface of fiber. Preparation method comprises exposure of polymer solution to electric field to form accelerated solution strands. Subsequent vaporization of solvent provides formation of fine fiber. Fibers are collected on a substrate and subjected to heat treatment at temperature not superior to melting point of polymer. From thus obtained fiber, fine-fiber material is manufactured.
EFFECT: manufacture of high-durability and high-strength fibers.
31 cl, 21 dwg, 5 tbl, 18 ex
FIELD: chemistry; production methods of composition for thread coating.
SUBSTANCE: composition includes x) = 10-50 mass.% of polyethylene wax with melting temperature from 110 to 150°C, y) = 10-50 mass.% compound ether compositions of conjoint polymer produced from α-olefine containing from 10 to 24 carbon atoms and unsaturated dicarboxylic acid selected from maleinic acid, fumaric acid, itaconic acid and citraconic acid z) = 100-(x+y) mass.% of silicon oil composition with 100 to 100- MPa-c viscosity at 20°C. Threads, fibres or filaments produced by spinning, stretching and texturing, if necessary, are subject to treatment with the specified composition.
EFFECT: items are ensured with high resistance property.
17 cl, 2 tbl, 3 ex
SUBSTANCE: invention can be used for extracting metal ions, purifying waste and industrial solutions from toxic metal ions. The method of obtaining anion-exchange fibre material involves reacting activated polyacrylonitrile fibre nitron and 30-70 wt % modifying agent - mixture of diethanolamine with 10-30 wt % hexamethylenediamine in an aqueous 5% solution of dimethylformamide. Nitron is activated in a 3-6% aqueous alkaline solution for 3-5 minutes at 90-95°C.
EFFECT: invention makes it easier to obtain fibrous anionite and can be used for effective purification waste water from leather industry and electroplating plants from chromium (VI) ions, and for concentrating and separating chromates from industrial solutions.
1 tbl, 4 ex
SUBSTANCE: monofilament contains conducting material and binding agent. The fabric that dissipates static charge includes polymer monofilaments containing conducting material containing metal particles and binding agent, which is attached in the form of solid coating in longitudinal direction of the above monofilaments or solid film in longitudinal direction, which is applied to them. The above monofilaments have static charge dissipation properties.
EFFECT: invention provides creation of threads to be used in industrial fabrics, for which static charge dissipation is compulsory.
21 cl, 5 dwg
FIELD: production of fire resistant polyacrylonitrile textile fibers.
SUBSTANCE: claimed method includes continuous thermal treatment of continuous fiber in air media, exothermal heat discharge and pyrolysis product extraction. Continuous tows of 30-40 ktex in thickness with tows of 0.1-0.4 tex in length are heated in four steps: at 150-190°C; at 200-215°C, at 220-240°C, and 250-280°C while fiber draft is 5-30 %. Then fiber is formed to produce crimpiness of 3-7 crimps/cm. Continuous fiber may be cut on sections of 20-125 mm in length.
EFFECT: fire resistant fiber with high strength and elastic characteristics.
3 cl, 6 ex
FIELD: production of fibers from polyacrylonitrile and its copolymers ; textile industry; production of industrial fibers.
SUBSTANCE: proposed method includes dissolving of polyacrylonitrile or its copolymer, molding polymer solution in form of fiber by passing it through spinneret, directing the solution in form of fiber to receiving member which is movable relative to spinneret in such way that fibers are not get in contact followed by gelling the solution, replacement of solvent in gel by polymer precipitating agent and removal of precipitating agent at subsequent extraction. Proposed method makes it possible to obtain fibers from polyacrylonitrile or its copolymers at molecular mass of 6*104 g/mole possessing rupture strength no less than 0.9 HPa and elasticity modulus not below 17 HPa.
EFFECT: enhanced efficiency.
SUBSTANCE: invention relates to using zinc sulfide in articles possessing N antibacterial and antifungal activity. In particular, it can be used in preparing any product able to interact with microorganisms and/or fungi, such as dress, carpets, curtains, bed affiliations and textile materials used for medicinal aims.
EFFECT: valuable properties of articles.
6 cl, 8 tbl, 7 ex
SUBSTANCE: polymer is soluble in a polar organic solvent and is modified in said solvent by an amine-based compound and an oxidising agent. The polymer has a structure which gives signals in the region of 150-200 h/million, determined via 13C-NMR, where the orientation of molecules according to measurement results obtained via wide-angle diffraction of X-ray radiation is 65% or higher, and specific weight is equal to or greater than 1.35.
EFFECT: fibre has high fire-resistance and strength retention value.
2 cl, 5 dwg, 30 ex