Thread made from poly(vinylidene sulfide), knitted mesh and a method for manufacture thereof
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
The invention relates to the technology for production and modification of chemical fibers and filaments, in particular PVDF (PVDF), and products from them, and can be used in chemical industry for production of filter materials and in medicine as a surgical suture thread and implants (implants) with biological activity and thromboresistant.
Known PVDF thread obtained by the method (copyright certificate №1120724, D 01 F 11/04), namely, that the polyolefin fibers grafted with grades of treated 20-25% solution of potassium hydroxide in ethanol-tetrahydrofuran at a ratio of from 10:90 to 90:10 on the air for 8-10 hours the disadvantages of the method are unsatisfactory performance in adhesion of platelets, a longer duration of treatment, use of bicomponent solvent, which complicates its regeneration, as well as the presence of the pre-grafted copolymerization of vinylidenechloride, which greatly complicates the process of obtaining material. In addition, the presence in the received thread grafted chains cannot provide solid kurbinovo coating, which negatively affects both the biocompatibility and thromboresistance and physico-mechanical properties of the obtained products.
A method of obtaining tremor sistemnogo material (journal proceedings of the Academy of Sciences, a series of chemical, 1993, No. 3, s), which lies in the fact that the poly (vinylidene fluoride) with the aim of obtaining kurbinovo coverage is affected by a mixture of saturated solution of potassium hydroxide in ethanol with acetone in the ratio 10:90. The disadvantage of this method is that the material obtained by this method has low thromboresistance and biocompatibility (insufficient for medical materials) due to the presence on the surface of 7% fluorine. In addition, regeneration of the solvent is difficult because of bicomponent composition, both components are flammable substances (flammable liquids), which increases the Flammability of the production.
Known knitted mesh fluoropolymer Teflon used as vascular prostheses (Lebedev L.V., Plotkin L.L., Smirnov A.D., Vavilov V.N., Lukyanov, Y., G. Gorbunov. The artificial blood vessels. SPb.: The Admiralty, 2001, p.46), with the density of the loops 20 to 1 cm, the number of pores of from 460 on 1 cm2and the permeability of the walls of the 1.04 l/min the Disadvantage of these vascular prostheses is that they have low thromboresistance and biocompatibility, which negatively affects the recovery process vessels.
The closest source for object "thread" is a thread made of PVDF with karbinovym the floor, going to a depth of do%, diameter of 50 μm, obtained by the method (patent RF №02115438, publ. 20.07.1998). How is that polyvinylidenechloride thread is treated with a saturated solution of potassium hydroxide in a mixture of methyl alcohol and acetone in their mass ratio 10:90 at a temperature of 18-20°for 20-50 min with simultaneous influence of ultrasonic field. Disadvantages obtained in this way threads are not sufficiently high strength properties and low enough values of the sorption of platelets. The disadvantages of the method are the need of the use of methyl alcohol, referred to particularly dangerous toxic substances, and acetone, both components are flammable (flammable liquids) substances, in addition, the use of bicomponent solvent makes its regeneration. And that for the implementation of the method requires additional equipment - ultrasonic generator, makes the production even more harmful because of the influence of ultrasonic field on the staff and on the strength characteristics of the fibers in the direction of their deterioration. Thus, there is a complex technological process of making yarn from carbin.
The closest analogue for the knitted mesh is a patent (U.S. No. 6638284, MCI And 61 F 002/00, from October 28, 2003), which describes the knitted mesh from PVDF, having from 40 to 80 rows per inch (16 to 31 rows 1 cm) with a triple combination of rows of twisted or monofilament thread with settings for the front row: 2/2, 2/1, 2/3, 2/1, 2/3, 1/0, 1/2, 1/0: medium range: 1/0, 2/3, 2/3, 1/0, 1/0, 2/3, 2/3, 1/0: rear series: 1/0, 1/2, 1/0, 1/2, 1/0, 2/3, 2/1, 2/3, content then from 55 to 68% and having satisfactory tensile strength from 100 to 140 inch pounds (from 0.67 to 0.94 MPa). The net gain on known equipment type knitting machines Tricot or Rasche and used as surgical implants. The disadvantage of the grid is low rates of thromboresistance due to the lack of surface monofilament kurbinovo coating, which can lead to complications in the postoperative period. In addition, the porosity values indicate a high content material of the filaments, which negatively affects the healing process. The use of mesh in chemical industry limited due to the low wettability of the surface of aqueous liquids.
Technical problem on which the invention is directed, is the increase in the resulting products (filament and grid) physico-mechanical properties while simultaneously giving properties such as chemical inertness, thromboresistance, biocompatibility and catalytic activity.
The problem is solved is eat, that:
a thread made of PVDF, has kurbinovo floor and is characterized by the following parameters: diameter of 0.10-0.15 mm, the linear density from 13,81 to 31,09 Tex, durability node 621-640 MPa and tensile strength 632-648 MPa;
- knitted mesh made of PVDF monofilament thread, the grid structure is characterized by the density 12-13 stitch rows 1 cm and contains loops of the two systems of threads with the parameters of the first system: 6/7, 3/2, 4/5, 1/0, 4/5, 3/2 and the second system: 1/0, 2/3, 1/0, 2/3, 1/0, 2/3,
the method of obtaining the above-described knitted mesh is that you get the knitted material of PVDF monofilament yarn diameter of 0.10-0.15 mm, density 12-13 stitch rows 1 cm using two systems of threads with the parameters of the first system: 6/7, 3/2, 4/5, 1/0, 4/5, 3/2 and the second system: 1/0, 2/3, 1/0, 2/3, 1/0, 2/3, impregnate his dimethylsulfoxide (DMSO) or dimethylformamide (DMF) for 1-4 h and treated with 15-17% solution of potassium hydroxide in n-butanol or n-propanol at 60-80°C. the Optimal processing time is 0.5-4 hours
Technical problem on which the invention is directed, is to simplify the technology of knitted mesh of PVDF monofilament yarns of different diameters with karbinovym coated with thromboresistant properties and biological compatibility, higher rates on durable the STI on the gap (the ball) was 1.58 MPa and higher content of pores (76-83%). The result is achieved through the use of less material-intensive two-row grid, exceptions are very toxic and simultaneously flammable substances, when using a one-component high-boiling solvent, reduce the concentration of potassium hydroxide and exclude the application of ultrasonic fields.
The inventive method is implemented as follows.
Examples (thread). PVDF monofilament bursting strength 648-632 MPa and strength in the node 640-621 MPa 0.1 to 0.15 mm and a length of 20 meters placed in 30 ml of DMF or DMSO and incubated for 1-4 h, then the thread is immersed in 15-17% solution of potassium hydroxide in n-butanol or n-propanol at a temperature of 60-80°s With a duration of 0.5 to 4 hours After this monofilament washed from potassium hydroxide to a pH of 7.3. The properties of the yarn depending on the parameters of the method are presented in table 3.
Examples (grid). On dwuhstupencato car from PVDF monofilament yarn with a diameter of 0.1 mm get knitted mesh (implant-implant soft tissues) with a density of 1 cm 12 stitch rows with two systems of threads with the parameters of the first system: 6/7, 3/2, 4/5, 1/0, 4/5, 3/2 and the second system: 1/0, 2/3, 1/0, 2/3, 1/0, 2/3, which is subjected to preliminary swelling in dimethyl sulfoxide for 1.5 h, then spend processing a 15% solution of potassium hydroxide in n-propanol in those who tell 1 h at a temperature of 60° C. and Then washed off the grid potassium hydroxide to pH 6,0-6,9, dried. The result is a material with a porosity of 83%and a tensile strength bead of 2.86 MPa and the rate of adhesion of platelets to 1.00. Other examples are summarized in table 3.
Example 43. Medical-biological tests were carried out on 18 rabbits breed "Chinchilla", which is implanted on Newroz of recti mesh knitted graft of PVDF of monofilament with karbinovym coating, and the grid structure is characterized by the thread diameter of 0.10-0.15 mm, density 12-13 stitch rows 1 cm and contains loops of the two systems of threads with the parameters of the first system: 6/7, 3/2, 4/5, 1/0, 4/5, 3/2 and the second system: 1/0, 2/3, 1/0, 2/3, 1/0, 2/3. Histological examination of muscle-nevroticheskikh fragments of the abdominal wall with an implanted material was carried out on terms of 3, 7 and 14 days, 1, 2, and 6 months from the beginning of the experiment.
When examining histological preparations implanted endoprosthesis of PVDF monofilament strands found that on the 3rd day of the experiment material surrounded by a thin layer of loose fibrous connective tissue adjacent areas where friable, edematous and slightly infiltrated segmented cells and lymphoid-macrophage elements. In 3 animals (22,2%) showed inflammatory changes, to the which was swelling and hyperemia of the edges and the formation of a certain amount of serous-hemorrhagic discharge.
After 1 week between the threads of the implant appears thin layer of loose connective tissue. There have been isolated macrophages and leukocytes, but clear signs of inflammatory reactions are absent. In 4 animals of inflammatory changes are minimized. When revision of the RAS, otmecheno that the endoprosthesis is in a thin layer of connective tissue. After 2 weeks the threads of the implants in all animals around fine-fibrous connective tissue. To the surface of the filaments adjacent the fibroblast and cell grows young connective tissue rich in collagen fibers and blood vessels. Cellular markers of inflammation also not defined. After 1 month niti implants surrounds layered connective tissue capsule. Cells (fibroblast) of the inner layer are stretched and flattened. In the intercellular substance formed collagen fibers, indicating that further maturation of the connective tissue. After 2 months around the threads and loops of the endoprosthesis is a layer of Mature connective tissue, containing flattened fibroblasts and collagen fibers. After 6 months the histological pattern of the implanted endoprosthesis was similar to the previous one. Signs of inflammation were absent.
When implantation of the endoprosthesis of the PVDF monofilament yarns with karbinovym coated grey not abradale in any case, the timing of the formation of Mature connective tissue capsule was reduced from 2 to 1.5 months, which indicates a higher biocompatibility of the material.
Table 1 presents the properties of the PVDF monofilament threads for receiving the threads and knitted mesh with karbinovym coating (examples I-V).
Table 2 shows the characteristics of the prototype and the proposed materials for the mesh materials without kurbinovo coating (examples V-VI).
In table 3 shows the parameters of the process of obtaining kurbinovo coverage and characteristics of the products obtained (examples: 1-38 object "thread", 39-46 object "knitted mesh and 47, 48 application - filtering material). Used in medical practice as described in example 43.
The advantage of the present invention in comparison with the prototype is that getting carbin is carried out in a single solvent is n-butanol or n-propanol, which facilitates the regeneration of the solvent, thereby reducing the cost of products. In addition, the concentration of potassium hydroxide (15-17%) lower than in the prototype, this leads to reduced demands on the corrosion resistance of the equipment. The decrease in the concentration of potassium hydroxide allows to obtain materials for surgery with a higher strength values, namely 1,58 MPa against 0,94 MPa. High strength properties according to the claimed methods which have achieved by the structure of the mesh graft, education on the surface of the threads kurbinovo coverage in the complete absence of fluorine in the layer carbin, which is achieved due to the greater length and in more mild conditions of the process. It should also be noted that adhesion is a surface phenomenon (Chemical encyclopedia, vol. 1, M.: Soviet encyclopedia, 1988, p.54), and, accordingly, the degree of transformation of the whole of polyvinylidene fluoride in carbin has little effect on the adhesion interaction between the surface of the fibers with the environment, namely with platelets.
From the data presented in table 3, it is seen that in the whole range of proposed options (examples 3-38) for the thread diameter of 0.10 mm process strength higher than that of the prototype. The increase in the duration of swelling threads in dimethyl sulfoxide results in lower strength (examples 3-5). And reducing a time less than 2 hours and the rate of adhesion of platelets becomes equal to the value of the prototype (example 4, 13, 17, 20, 22, 26, 29, 35 and 38). The range of the claimed temperature is justified by the fact that the lower limit is determined by the solubility of potassium hydroxide sufficient to obtain kurbinovo cover, allowing to obtain an indication of the adhesion of platelets at the level of the prototype, and the upper limit is determined by the resistance kurbinovo cover and the realization of the stated strength characteristics of threads (example 7, 16, 25 and 34). About aiternate processing less than 1 hour results in adhesion of platelets at the level of the prototype (example 8, 17, 26 and 35), and the increase in time over 4 hours does not improve the rate of adhesion of platelets. The concentration range is determined by the solubility of potassium hydroxide in n-butanol and n-propanol when the claimed temperature processing, providing the properties of the obtained surgical materials in terms of adhesion of platelets (example 3-38).
Examples 39 and 40 of the characteristics of the grafts mesh of monofilament yarn diameter of 0.10 and 0.15 mm (13,81-31,09 Tex). As can be seen from examples 39 and 40, the number of loops 1 cm does not affect the adhesive properties with respect to platelets.
Examples 47 and 48 show that the diameter of the filaments does not affect the electrical resistance of the filter media.
Thus, the claimed combination of signs in General provides the technical result of the increase in the resulting products (filament and grid) physico-mechanical properties while simultaneously giving properties such as chemical inertness, thromboresistance, biocompatibility and superior properties of filter materials.
Properties of PVDF monofilament threads for receiving the threads and knitted mesh with karbinovym coating
|No.||Diameter/linear density, mm/Tex||Strength||Strength in the site|
|III (prototype for thread)||0,05/of 3.46||603/0,34|
|IV (prototype for the grid)||0,10-0,25/13,81-88,08|
Characteristics of the prototype and the proposed materials without kurbinovo cover
|No.||Machine for receiving an implant||The first system||The second system||Porosity, %||Tensile strength, MPa||The number of stitch rows 1 cm||The diameter or linear density yarn|
|V||The prototype mesh material||Triggerevent machine||Front row: 2/2, 2/1, 2/3, 2/1, 2/3, 1/0, 1/2, 1/0||The average number of 1/0, 2/3, 2/3, 1/0, 1/0, 2/3, 2/3, 1/0||Back row 1/0, 1/2, 1/0, 1/2, 1/0, 2/3, 2/1, 2/3|| |
0,25 the m
|VI||Declare mesh material||Dukhrana machine||6/7, 3/2, 4/5, 1/0, 4/5, 3/2||1/0, 2/3, 1/0, 2/3, 1/0, 2/3||76-83||2,16 -|
1. The thread is made of PVDF and having kurbinovo coating, characterized in that it has a diameter of from 0.1 to 0.15 mm, the linear density from 13,81 to 31,08 Tex, durability node 640-621 MPa and tensile strength 648-632 MPa
2. Knitted mesh made of PVDF monofilament yarn according to claim 1, which structure is characterized by the density 12-13 stitch rows on 1 cm2and containing loops of the two systems of threads with the parameters of the first system 6/7, 3/2, 4/5, 1/0, 4/5, 3/2 and the second system 1/0, 2/3, 1/0, 2/3, 1/0, 2/3.
3. A method of obtaining a knitted mesh under item 2, characterized in that of the PVDF thread get knitted material density 12-13 stitch rows on 1 cm2and DV of the two systems of threads with the parameters of the first system 6/7, 3/2, 4/5, 1/0, 4/5, 3/2 and the second system 1/0, 2/3, 1/0, 2/3, 1/0, 2/3, impregnate his dimethylformamide or dimethylsulfoxide within 1-4 h and treated with 15-17%solution of potassium hydroxide in n-butanol or n-propanol at 60-80°C.
4. The method according to claim 3, characterized in that the processing of 15-17%potassium hydroxide solution is conducted for 0.5-4 hours
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: 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
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
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: 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.
FIELD: organic chemistry, chemical technology.
SUBSTANCE: invention relates to chemical modification of dioxane alcohols and their mixture with their esters and formals that are waste in manufacturing isoprene and used, in particular, as a secondary plasticizing agent in manufacturing polyvinyl chloride compositions. As a modifying agent method involves using at least one substance taken among the group including cyclic anhydride (preferably maleic anhydride, phthalic anhydride, phosphoric anhydride, succinic anhydride, waste in manufacturing phthalic anhydride) or cyclic amide (preferably caprolactam, butyrolactam) taken in the mass ratio alcohol (or mixture of alcohols with esters and formals):modifying agent = (0.56-400):1. Treatment is carried out at temperature 100-180°C for 2-6 h. Invention provides increasing yield of product, replacing high-expensive raw for inexpensive and more available raw, reducing temperature of the process, reducing acid number and the content of volatile impurities in the end product.
EFFECT: improved modifying method.
3 cl, 4 tbl, 12 ex