A method of obtaining a polymer protective coating
(57) Abstract:The invention relates to a method for producing polymer coatings with high protective physico-chemical properties, low toxicity, suitable for implantation in tissue of living organisms. Pre-prepared polymer composition, which is mixed in the mixer methyl ester of methacrylic acid and the polymerization initiator is a peroxide compound, and water. Additionally, the composition can enter the ammonium persulfate. The polymer composition is applied onto the substrate, dried, utverjdayut at 70-90oWith 40-48 hours and Then cured layer is treated with a stabilizing reagent of the two main groups of carboxylic acids. Then the layer is dried at 70-90oC for 40-48 hours the Combination of components in a certain ratio reduces the toxicity of the coating, to improve physical and mechanical properties and to allow implantation in biological objects. 1 C.p. f-crystals, 1 table. The invention relates to organic chemistry, and in particular to methods of obtaining protective polymer coatings, which can be used for protection of active metal from exposure to the environment, as well as in layered whom is the method of obtaining a polymer coating.with. The USSR 2050392, CL MCI 09 J 4/02, publ. 20.12.95 bull. 35 ).The known method includes a preliminary preparation of polymeric compositions containing as polymerized basics cyclohexylmethyl or butylmethacrylate, 2-ethyl hexyl acrylate is a compound from the group of esters of methacrylic acid and methacrylate of metildigoxin as a peroxide polymerization initiator. The polymer composition is then applied to the substrate and utverjdayut.The disadvantages of this method are not sufficiently high protective properties of the coating as a result of toxic, reactive products, accompanying the curing process, is not sufficiently high optical and strength properties, as well as the absence of the possibility of implantation of the coating in the tissue of living organisms, specifically in the eyes in the form of a lens (lens) of the eye.The closest in technical essence to the claimed is a method of obtaining a protective polymer coating, including a preliminary preparation of polymer compositions based on polycarbonate and polymethylmethacrylate (A. A. Berlin and other Preferability. M.: Nauka, 1967, S. 450-459), which are compounds from the group of the complex is the composition on a substrate and termootdelenii layer at a temperature of more than 100-150oC.The disadvantages of this method include increased toxicity due to the significant release of reactive residual monomer in the process of curing of the composition that excludes the use of ready-made material for protection and for implantation in a biological objects, as well as the lack of quality of this material in the form of low optical and structural properties.The technical problem solved by the invention, is to develop a method of producing a protective polymer coating that is resistant to aggressive environmental factors, characterized by a high physical-chemical properties and biocompatibility with living tissues, providing the possibility of implantation.A new technical result achieved when using the proposed method, compared with the prototype is to improve the quality polymer coating by improving its protective properties, physico-chemical parameters and toxicity reduction.The specified technical task and the technical result is achieved by the fact that in the known method, including preliminary when the esters of methacrylic acid, but as the polymerization initiator is a compound from the group of organic peroxides, the subsequent application of polymer composition on a substrate, heat treatment and hardening, in accordance with the proposed method after curing under the conditions of heat treatment at a temperature of 70-90oC for 40-48 hours polymeric layer on the basis of the composition containing the following ingredients, wt.%:
Compound from the group of organic peroxides - 0,5-1,0
Water - 24,5-37,0
Ester of methacrylic acid - Rest;
its surface is further treated with a stabilizing reagent from the group of the dibasic carboxylic acid and finally dried coating under these conditions of heat treatment.In addition, before curing in polymer composition further added ammonium persulfate, in the following reagents, wt.%:
Benzoyl peroxide - 0,5-1,0
Water is 24.5-37
The ammonium persulfate - 0,8-1,0
Methyl ester of methacrylic acid - Rest
Additional technical result is to further improve the quality of the coating due to the stabilization of the structure.The essence of the proposed method is illustrated as follows.Using the method of reagent from the group of peroxides (benzoyl peroxide, hydrogen peroxide) below the proposed limit of the ratio is not conducive to a comprehensive polymerization in the amount of the coating layer and the emergence of separate sealed parcels in mass. This reduces the physical and mechanical properties of the cured polymer layer. The excess content of initiator leads to the acceleration of polymerization, results in an inhomogeneous layer structure, which has a detrimental effect on the optical, physical and mechanical screening of the security polymerization initiator peroxide type preferably used in the form of aqueous solutions.Additional stabilizing effect and decrease toxicity in the experiment were obtained using a stabilizing layer structure of the reagent in the form of ammonium persulfate in the claimed limits of the ratios. Moreover the increase of its content is above the limit value contributes to the emergence of centers of parasitic crystallization in the thickness of the coating layer and, as a consequence, the emergence of fragile sites. This is essential for long term storage of material prepared for implantation, because it dramatically decreases the time the viability of the layer.In case of reduction of the content of the stabilizing reagent reduces the pot life of the layer due to lack of quantity for long locks emerging linkages in the polymer chains.These components are mixed in a reactor in the stated proportions and put the prepared composition on the prepared substrate. Samples of the coating is placed in a heat treatment zone and maintained under the stated conditions of heat treatment for 40-48 hours. After curing of the coating it is subjected to further processing of the stabilizing reagent. Next is the final of suii heat treatment).It is known (Morphological and biochemical aspects of biodegradation of polymers / edited by G. A. Pkhakadze. Kiev: Naukova Dumka, 1986) that the biological compatibility is determined by the absence of toxicity factors, which include the products of biodegradation of the polymer material, which should not cause the body harm either in the first period of destruction, nor in some time after the destruction of the polymer implant (C. 58, paragraph 3). It is determined, in turn, the chemical composition of the polymer, and the structure and adhesive properties of the surfaces of polymers (S. 62, paragraph 2). Confirmation of the decision of a task of the invention to ensure the biological compatibility of the composition with the biological tissues of animal organisms, is the elimination of residual monomer, which is a toxic substance, related to malicious factors, the formation of which in this way excluded due to the chemical nature of the substances. With this in mind, a study of the biological compatibility was carried out under conditions of exposure to biological fluids (serum, saline solutions), allowing you to simulate natural conditions and to eliminate the need to conduct research on animal organisms which has the desired quality of the coating due to the high optical and physico-mechanical properties:
residual ultimate tensile stress of not less than 76 MPa;
optical fractorama surface visually does not contain structural and spiral formations;
toxicity is minimized to zero - values of residual monomer in the composition of the cured coating.These properties experimentally obtained on the coating subjected to the heat treatment at 79-90oC for 40-48 hours and treated with an aqueous solution of reagent from the group of the dibasic carboxylic acid concentration of not more than 0.1 mol/l and the optimum estimated amount of the reagent in the range of 1.0-2.0 wt.h. for each 100 wt.h. polymeric compositions.The obtained polymer coating in terms of the proposed method is characterized by a high level of protective properties, non-toxicity, high mechanical and optical performance.This material is in the form of individual layers may be suitable for composite materials used as implants in the tissues of living organisms, for example in the manufacture of the lens or in the bone.Experimentally it was shown that in the case of its application is not rejected SV">Other technical and economic advantages of the proposed method are the availability and cheapness of the raw materials used, ease, making possible the organization of serial production.The industrial applicability of the method is confirmed by the following examples of implementation.Example 1. Originally prepared in laboratory conditions, the composition of the following components (semi - samples of PMMA), wt.%:
Methyl ester of methacrylic acid - 62
Benzoyl peroxide - 0,4
Water - 36,8
The ammonium persulfate - - 0,8
Components are mixed in the reactor and is applied on a substrate of glass using the method of pressing. Then the samples with the composition is subjected to heat treatment at a temperature of 90oWith in 48 hours.Thus prepared samples size (807,50,8 mm) treated with 0.1 M solution in terms of this example, oxalic acid and subjected to final drying in the conditions of heat treatment at a temperature of 70-90oWith in 48 hours. Then the samples were tested for compliance with the physical-mechanical indicators, together with samples of industrial production brands: SOL (GOST 10667-90E) unpainted or painted.
Compound from the group of organic peroxides - 0,5-1,0
Water - 24,5-37,0
Ester of methacrylic acid - Rest
its surface is further treated with a stabilizing reagent from the group of the dibasic carboxylic acid, and finally dried coating under these conditions of heat treatment.2. The method according to p. 1, wherein before curing in polymer composition further added ammonium persulfate, in the following reagents, wt.%:
Benzoyl peroxide - 0,5-1,0
Water - 24,5-37,0
The ammonium persulfate - 0,8-1,0
Methyl ester of methacrylic acid - Ostalnoe
FIELD: processes for applying fluent materials to surfaces to obtain anti-friction surface with the purpose to reduce hydraulic and aerodynamic friction of vehicle moving in liquid and to reduce friction in friction assemblies of machines and mechanisms working in aqueous medium.
SUBSTANCE: method involves obtaining and applying antifriction coating on vehicle body so that specific coating surface energy along liquid streamlines (streamline surface) has negative gradient.
EFFECT: reduced friction due to provision of friction resistance control.
FIELD: processes to apply liquid or fluent material to obtain an anti-friction or anti-adhesive surface, particularly to produce siliconized wrapping paper.
SUBSTANCE: method involves mixing organopolysiloxanes-based silicone composition components; applying the obtained composition on movable paper substrate; heat-treating the obtained coating up to full coating hardening. Above paper substrate is wet-strength paper web with 6-8% moisture content. The paper is preliminary subjected to calendaring operation to obtain 1.0-1.1 g/cm3 density and 250-400 sec. smoothness. Silicone composition is applied by doctoring method, wherein silicone composition from local bath is applied on paper web moving between doctor blade and rear support. At least part of rear support surface in contact area between doctor blade and rear support is resilient. Degree of paper web bending during doctor blade introduction in the rear support is regulated by change in rear support surface resiliency. Unit for silicone composition application comprises doctor and rear support having changeable resiliency at least in contact area between rear support and doctor blade. Doctor blade is installed at acute angle to line perpendicular to rear support base and passing through contact line between rear support and doctor blade. Local bath is arranged in space defined by doctor blade and paper web.
EFFECT: increased application properties and strength of the paper, provision of reliable peeling force to paper separation from adhesive layer within wide temperature range, increased quality of composition application due to increased fullness of composition introduction in surface layer of paper web.
13 cl, 2 dwg
SUBSTANCE: method comprises securing means of the anchor fastening to the surface, applying the lining material on the surface, solidifying the lining, AND drying the lining at a temperature sufficient to the melting of the coating at the means of anchor fastening. The device for anchor fastening is proposed.
EFFECT: enhanced reliability.
16 cl, 1 tbl, 3 ex
FIELD: machine engineering, namely modification of rubbing surfaces of kinematic pairs.
SUBSTANCE: method comprises steps of placing between rubbing surfaces disintegrated mineral composition containing synthetic modification of serpentine produced by diluting in water mixture of α-quartz and magnesium hydroxide at temperature 120 - 170°C and pressure 1.2 - 15.0 at for further formation of crystals. Chrysotile having monocline syngony with coordination numbers 5.0< a< 7.3A°, 9.0<b< 9.2A°, 7.0<c< 7.3A° and with angles β between positive directions of crystallographic axes 90° or 93° is used as seed for producing crystal of synthetic modification of serpentine. Summed value of molar masses of α-quartz and magnesium hydroxide corresponds to molar mass of synthetic modification of serpentine. Composition includes in addition homologs of fullerenes Cm where m ≥ 60 at next relation of components, mass %: synthetic modification of serpentine, 70 - 90; homologs of fullerenes Cm, 10 - 30. Invention allows to form coating with receive friction factor lowered to 0.001, increased hardness HRC 90 - 95.
EFFECT: enhanced wear resistance, increased useful life period of coating, possibility for realizing method with use of oil lubricant and also without any lubricant.
FIELD: anti-adhesion materials.
SUBSTANCE: invention relates to a composition comprising 0.1-4% of mixture of perfluoropolyoxaalkylene carboxylic acids of the general formula: wherein n = 3-50. For preparing colloidal solution of perfluoropolyoxaalkylene acid the composition comprises additionally 1-2% of amidoalcohol of the general formula: wherein n = 0 or 1; m = 1 at q = 1 and m = 2 at q = 0 that is prepared by interaction of dimer and/or trimer of hexafluoropropylene oxide with mono- and/or diethanolamine and water, up to 100. After treatment with the proposed composition surface of solid bodies acquires water-oil-repelling properties and the gluing seam rupture strength is reduced by two orders that accords with strength levels providing by the nearest analog representing a mixture of perfluoropolyoxaalkylene acids in coolants. Invention can be used for decreasing adherence of moldable plastic, crude rubber articles and other polymers to a tool and press-forms.
EFFECT: improved and valuable technical properties of composition.
1 tbl, 2 ex
SUBSTANCE: contamination protector contains fine particles of nitrogen dioxide, aqueous solvent containing alcohol dispersing specified particles of nitrogen dioxide, surface-active substance and splash modifier chosen among alkali metal compound, alkaline-earth metal compound, phosphorus compound, clay mineral and mixtures thereof. Specified contamination protector enters into the composition of specified aqueous solvent. It can be applied onto building board coating.
EFFECT: contamination protector and its adhesion to building board coating are enhanced.
3 cl, 30 dwg, 3 tbl, 30 ex
SUBSTANCE: antifriction coat can be used in gear pumps for reducing friction and wear resulted from corrosion or mechanical effects in tribojoints under effects of chemically active reagents, high temperature and loads on engaged parts to ensure required stable gaps between the said parts. The antifriction coat consists of three layers, i.e. inner, intermediate and upper layers. Note here that the inner layer represents a composition comprising 90 wt % of a polyimide varnish and 10 wt % of chromophosphatealuminic bond, the intermediate layer being made from 100 wt % of a pure polyimide varnish. Finally, the top layer represents a composition containing 90 wt % of polyimide varnish, 8 wt % of colloid graphite and 2 wt % of lecithin. Thickness of the aforesaid inner layer is within the limits of from 8 up to 10 mcm, thickness of the intermediate layer is within the limits of from 16 up to 20 mcm, thickness of the top layer is within the limits of from 24 up to 30 mcm, while the required thickness of the coat is provided by grinding the top layer.
EFFECT: longer life of friction assembly units and parts operated in chemically active environments.
FIELD: personal utensils.
SUBSTANCE: nonstick coating consists of, at least, one first primary layer spread over the base and covered with one or more upper layers on the bases of fluorocarbon resins. Primary layer includes, in the ratio of dry components weight to total composition from 9 to 15 wt %, fluorocarbon resin, from 4 to 5 wt %, polyamidoimidic resin (PAI), from 0.12 to 1.1 wt %, polyether ether keton resin (PEEK), and residual consisting of technological supplements, inert fillers and dispersion media.
EFFECT: invention secures better resistance of the nonstick coating to scratching due to reduced weight content of PEEK in the composition of the first basic layer.
9 cl, 2 tbl
FIELD: technological processes.
SUBSTANCE: this invention is related to structure including substrate and tempered anti-adhesion coating on substrate. Such coating includes lower coating and upper fluoropolymer coating, in which mentioned lower coat comprises magnetic scales and multiple silicon carbide particles.
EFFECT: development of coat with improved heat transfer properties, improved resistance to abrasion and proper slipping.
16 tbl, 4 ex