Powder rubber (mixture) and the method of production thereof
The invention relates to powder rubbers containing other components to obtain vulcanizate rubber compound and method of production thereof. Superfine rubber powder contains (a) a rubber matrix and optionally (b) one or more white and/or black fillers, optionally modified with one or more organosilicon compounds of formula (I), (II) or (III): [R1n(RO)3-nSi(Alk)m-(Ar)p]q[V] (I), R1n(RO)3-nSi(Alk) (II), or R1n(RO)3-nSi(alkenyl) (III), where In denotes-SCN, -SH, -Cl, -NH2(if q=1) or-Sx- (if q=2), R and R1denote a branched or unbranched alkyl group with 1-4 carbon atoms, phenyl residue, and all residues R and R1can have in each case identical or different meanings, and preferably they mean alkyl group, R denotes a branched or unbranched C1-C4alkyl, C1-C4alkoxygroup, n denotes 0, 1 or 2, Alk denotes a divalent linear or branched hydrocarbon residue with 1-6 carbon atoms, m represents 0 or 1, AG - Allenby residue with 6 to 12 C-atoms, R represents 0 or 1 when y is a saturated hydrocarbon residue with 1-20 carbon atoms, preferably 2-8 carbon atoms, alkenyl is a monovalent linear or branched unsaturated hydrocarbon residue with 2 to 20 carbon atoms, preferably 2-8 carbon atoms. To add rubber) one or more known additives to obtain a vulcanizate. Fillers add in two stages. The solid precipitate is separated by known methods. If necessary, washed and dried. The technical result consists in increasing the flowability and ease of processing rubber and mixtures and improve their properties, 2 c. and 13 C.p. f-crystals. Description text in facsimile form (see graphic part).
Claims1. Superfine rubber powder containing (a) a rubber matrix and optionally (b) one or more well-known white and/or black fillers, optionally modified with one or more organosilicon compounds of the formula (I), (II) or (III)[R1n(RO)3-nSi(Alk)m-(Ar)p]q[In]; (I)R1n(RO)3-nSi(Alk); (II)or R1n(RO)3-nSi(alkenyl), (III)where denotes the-SCN, -SH, -Cl, -NH2(if q=1) or-Sx- (if q=2);R and R1denote razwell the>can have in each case identical or different meanings, and preferably they mean alkyl group;R denotes a branched or unbranched1-C4alkyl, -C1-C4alkoxygroup;n = 0, 1, or 2;Alk denotes a divalent linear or branched hydrocarbon residue with 1-6 carbon atoms;m = 0 or 1;AG indicates Allenby residue with 6 to 12 C-atoms;p = 0 or 1, provided that p and m do not simultaneously denote 0,x = 2-8;alkyl is a monovalent linear or branched unsaturated hydrocarbon residue with 1-20 carbon atoms, preferably 2-8 carbon atoms;alkenyl represents a monovalent linear or branched unsaturated hydrocarbon residue with 2 to 20 carbon atoms, preferably 2-8 carbon atoms;C) one or more known additives used in the preparation of rubber vulcanizates.2. Rubber powder under item 1, characterized in that it contains one or more of the following additives in the conventional processing to a vulcanizate quantities: (a) zinc oxide and/or zinc stearate; (b) stearic acid; polyhydric alcohols; g) polyamine; d) resin, the wax is whether vulcanization; and do not necessarily sulfur, in particular, a modified surface-active agent, and the particle size of solids present in the rubber powder is preferably50 ám.3. The method of obtaining fine rubber powders filled by deposition from aqueous mixtures containing optional modified organosilicon compounds superfine(s) filler(s), representing the carbon black and/or silica filler, a water-soluble salt of a metal of groups IIA, IIb, IIIa or VIII of the Periodic system of the elements and natural latex or aqueous emulsion of a rubber solution, optionally in the presence of an organic solvent in two stages, and a) in the first stage50 wt.%, but less than 100 wt.% envisaged number of fine filler, the total content of which in the rubber powder is from 20 to 250 wt.h. on 100 wt.h. rubber, preferably in the form of an aqueous suspension with a content of from 2 to 15 wt.% in water, optionally together with one or more provided for surface modification of filler organosilicon compounds of formula (I), (II) or (III), Okha is f">50 wt.%, but less than 100 wt.% at least partially modified on the surface by one or more organosilicon compounds of formula (I), (II) or (III) the filler is mixed primarily in the presence of the emulsifier with natural latex or aqueous emulsion of a rubber solution and reduce the pH of the mixture to a value ranging from 7.5 to 6.5; (b) in the second stage adds the residual part of the above-mentioned finely dispersed fillers, optionally together with intended for surface modification of filler residual amount of organosilicon compounds of formula (I), (II) or (III) in the form of a suspension, reduce the pH to a value in the range of less than 6.5 to about 5, resulting in a mixture of rubber completely precipitates together with a filler; C) after which the precipitated solid precipitate is separated by known methods; d) if necessary, wash and d) is dried.4. The method according to p. 3, characterized in that in the first stage, reducing the pH of the mixture is carried out by adding a Lewis acid.5. The method according to any of the preceding paragraphs, characterized in that in the second stage the pH of the mixture is reduced to values around 5.5.6. The method according to any of the preceding paragraphs, characterized is that the number added in the form of a residual part of the second stage.7. The method according to p. 6, characterized in that when the total content of filler80 parts per 100 parts of rubber, 10 to 20 parts of this quantity is added in the form of a residual part of the second stage.8. The method according to any of the preceding paragraphs, characterized in that add carbon black with an average particle size of from 1 to 9 microns.9. The method according to any of the preceding paragraphs, wherein the white filler, which represents a precipitated silicic acid, used at least partially in the form of fully washed from salt precipitate on the filter.10. The method according to any of the preceding paragraphs, characterized in that before the deposition of the rubber powders in suspension/emulsion add the usual technological and/or vulcanizing additives specified in paragraph 2, subparagraphs (a)), provided that the particle size of the added solid components is <50 μm, preferably <10 μm.11. The method according to p. 10, characterized in that the suspension of a filler containing one or more of the above-mentioned technological and/or vulcanizing additives before adding the rubber component is passed through the apparatus for grinding.12. The method according to p. 10, characterized in that the suspension of the filler Ave the stage.13. The method according to any of the preceding paragraphs, characterized in that one or more of the components identified in paragraph 2, subparagraphs (a)) is mixed with an emulsion latex, respectively, the rubber solution or suspension of the filler and then the thus obtained emulsion latex, respectively, the solution of rubber mix in the first stage with the thus obtained suspension of the filler.14. The method according to any of the preceding paragraphs, characterized in that the accelerator (accelerator) vulcanization is mixed with rubber powder containing the above-mentioned additives (a-g), or suspended or dissolved in compatible with rubber oil and spray on rubber powder.15. The method according to p. 14, characterized in that together with the vulcanization accelerator is additionally applied sulfur.
FIELD: polymers, chemical technology.
SUBSTANCE: invention relates to the continuous method for preparing polytetrafluoroethylene (PTFE) or modified PTFE finely divided powders. The continuous method for preparing PTFE or modified PTFE finely divided powders involves the following steps: (a1) dilution of PTFE-latex of modified PTFE-latex prepared in polymerization in the dispersion-emulsion to the concentration from 5 to 25 wt.-% of PTFE or modified PTFE with possible filtration of the prepared diluted latex; (b1) molding latex with inert gas to the relative pressure with respect to atmosphere pressure in the range 3-40 kg/cm2 (0.3-4 MPa); (c1) addition of acid electrolyte solution to latex in the line-flow mixer at pH value 1-4; (d1) feeding the latex flow from the mixer through capillary tube under condition of turbulent current with the Reynolds number above 3000; (e1) gel prepared at step (d1) is coagulated onto granules at mechanical stirring with the specific power 1.5-10 kWt/m3 and stirring is maintained up to flotation of finely divided powder; (f1) below water is separated from the finely divided powder. PTFE of modified PTFE finely divided powders that can't be processed by thermal method prepared by abovementioned method show the following indices: apparent density is ≥ 470 g/l; average diameter of particles (D50) is above 200 mcm; distribution of particles by diameter determined as ratio between particles mass with diameter from 0.7 to 1.3 times with respect to average particles diameter and the total particles mass above 50%. Invention provides preparing powders without using the complex and expensive equipment, and powders possess the improved fluidity and show the apparent density and narrow distribution of particles by the diameter index.
EFFECT: improved preparing method.
9 cl, 1 tbl, 1 dwg, 6 ex
FIELD: polymer production.
SUBSTANCE: invention relates to production of polymeric binders for toner and can be used for copying appliances and printers. Process comprises separate preparation via emulsion polymerization of (i) low-molecule weight copolymer of styrene (α-methylstyrene), 2-ethylhexyl acrylate (or butyl acrylate) and methacrylic acid at monomer weight ratio (88-91.5):(8-11):(0.5-1.0) with intrinsic viscosity in toluene 0.08-1.2 dL/g and (ii) high-molecule weight copolymer of styrene (α-methylstyrene) and 2-ethylhexyl acrylate (or butyl acrylate) at monomer weight ratio (88-92):(8-12) with intrinsic viscosity in toluene 1.0-1.28 dL/g. In both cases, polymerization is carried out at 60-70% to monomer conversion close to 100%. Resulting latexes of low- and high-molecule weight copolymers are supplemented by stopper and antioxidant and then mixed with each other at "dry" weight ratio between 70:30 and 75:25 and coagulated intrinsic viscosity in toluene 1.0-1.28 dL/g. with electrolyte solutions to form polymer characterized by intrinsic viscosity in toluene 0.4-0.45 dL/g and polydispersity Mw/Mn, which ensures bimodal molecular weight distribution of copolymer. The latter has melting (spreading) point 125-137°C and softening temperature 70-75°C.
EFFECT: improved quality of electrographic printing.
2 cl, 1 tbl, 4 ex
SUBSTANCE: scope of invention covers stabilized water dispersions of curing agent suitable for coating preparation. Dispersion dispersed in water contains the following components: A1) at least one organic polyisocyanate with isocyanate groups connected in aliphatic, cycloaliphatic, araliphatic and/or aromatic manner, A2) ionic or potentially ionic and/or non-ionic substance, A3) blocking agent, B) stabilizer containing a) at least one amine with structural element of common formula (I) without any hydrazide group, b) substance with formula (IV) .
EFFECT: resistance to thermal yellowing increases.
6 cl, 5 tbl, 11 ex
SUBSTANCE: described is a fluoropolymer latex which contains a fluoropolymer and fluorine-containing emulsifier of formula (1): F(CF2)4OCF2CF2OCF2COOA, where A is a hydrogen atom, alkali metal or NH4. A method is also described for producing such latex, and a fluoropolymer, which is obtained by coagulating fluoropolymer latex. The fluoropolymer latex can be used as an agent for coating different materials, such as metallic substrates, inorganic oxide substrates, polymer substrates, synthetic fibre, glass fibre, carbon fibre or natural fibre.
EFFECT: fluoropolymer is useful as material with excellent heat resistance, oil resistance, chemical resistance, weather resistance, non-stickiness, anti-overgrowth properties, water-repellent properties, oil-repellent properties, solvent-repellent properties.
7 cl, 2 tbl, 14 ex
SUBSTANCE: invention relates to processes of separating polydisperse systems through vibroacoustic effect. The method of separating polydisperse solution of distillery stillage involves coagulation of colloidal and dissolved substances of a dispersed phase and subsequent separation of the solid fraction of the formed product from the solution with separation of the liquid fraction of the dispersed medium. The dispersed phase is coagulated in two steps by applying energy of acoustic vibrations on the solution in at least two spectra in the 1-18 kHz range, providing weakening of surface tension of colloidal and dissolved substances, and in the 80-400 Hz range, increasing their amplitude of vibration. Before coagulation of the dispersed phase from the solution through evacuation, volatile aromatic substances are separated in form of a condensate, and before the second step for applying energy of acoustic vibrations the solution is dehydrated by 20-50% in vacuum drying conditions with extraction of the water condensate.
EFFECT: invention provides environmentally safe non-waste technology of processing distillery stillage and widens the range of processed products.
SUBSTANCE: method is realised through granulation by stirring in water in the presence of a liquid organic solvent which is partially soluble in water. A polytetrafluoroethylene emulsion is added, as well as a coagulant for coagulation of the polytetrafluoroethylene emulsion in form of a surface layer of polytetrafluoroethylene granules containing filler.
EFFECT: obtaining granules with high looseness with low separation of filler, which prevents release of the polytetrafluoroethylene emulsion into liquid wastes.
12 cl, 1 tbl, 5 ex
SUBSTANCE: invention relates to a novel aqueous polytetrafluoroethylene emulsion obtained using a special fluorinated emulsifying agent, and to fine polytetrafluoroethylene powder and porous material produced from said powder. Described is a porous material produced from polytetrafluoroethylene via extrusion of a paste of fine polytetrafluoroethylene powder which is obtained through coagulation of aqueous polytetrafluoroethylene emulsion obtained during emulsion polymeristion of tetrafluoroethylene in an aqueous medium using a fluorinated emulsifying agent of formula (I): CF3CF2OCF2CF2OCF2COOA, in which A is an alkali metal atom or an NH4 group taken in amount of 1500-20000 parts per million relative the final output of polytetrafluoroethylene, followed by stretching.
EFFECT: obtaining porous material with excellent various characteristics, made from polytetrafluoroethylene, having excellent processability during extrusion of the paste.
5 cl, 3 ex, 1 tbl, 1 dwg