The method of producing polycarbosilane
(57) Abstract:Usage: upon receipt of inorganic fibers and other products consisting of silicon carbide. The inventive polycarbosilane get by thermal decomposition of polydimethylsilane at a gauge pressure of 1.5 - 6 ATM with shutter speed at 350 - 380oC for 2 to 10 h, the reset lehajtasa components and subsequent exposure at 390 - 450oWith over 30 - 80 hours 2 Il. , 1 table. The invention relates to methods of producing organosilicon polymer of polymer of the formula:
< / BR>(patent N 4220600, class C 07 F 7/08, 1980).Polycarbosilane (in pixels) of the formula (1) is used to obtain the inorganic fibers and other products, consisting mainly of silicon carbide.Structure and rheological characteristics of the polymer determines its ability to fiberizing and operational properties of SiC materials.A known method of producing polycarbosilane (1), partly containing siloxane links:
< / BR>(patent N 4159259, class C 07 F 7/60, 1979).The polymer is produced by heating a mixture of powdered polydimethylsilane (PDMS) and polypropyleneoxide in an inert atmosphere.Nedostatki and reduces oxidative and thermal stability of SiC fibers.The closest in technical essence of the present invention and adopted for the prototype is the way to get polycarbosilane formula (1) by thermal decomposition of polydimethylsilane at high temperature (470-500oC), a pressure of 95 - 100 ATM  for 15 - 20 hoursThe disadvantage of this method is the formation of large amounts of coke forming insoluble product, relatively low uniformity of polymer molecular mass composition, which leads to high breakage jet melt and stuck on filiere when the molding on the molding machine, as well as the complexity of the hardware design process.The task of the invention is to improve the quality of the product and the simplification of the apparatus registration process.The technical result is achieved due to the fact that polycarbosilane formula (1) obtained by step thermal decomposition of polydimethylsilane in an inert atmosphere. The process is carried out in three stages. In the first stage produce exposure at 350 - 380oC and a pressure 1.5 - 6 bar. In the second stage discharge boiling liquid components. The third stage is heated to a temperature of 390 the low temperature with the speed of its rise and a relatively small overpressure allows you to make this process more automated and to improve the quality of the PCB, that manifests itself in a more narrow molecular weight distribution polymer, a high content of Si - H groups, the regularity of the structure of the PCB, which is assessed according to the relative content of HSiC3groups, as well as the ability of the polymer to the formation, oxidation and strength characteristics of the SiC fibers.The difference of the proposed method is to conduct the process at a pressure of 1.5 to 6 ATM and heat treatment using manual mode (350 - 380oC for 2 to 10 h, and then 390 - 450oC for 30-80 h) and removal of boiling liquid fractions in the intermediate stages of polymerization.The invention is illustrated in Fig. 1, 2.The essence of the method consists in the following: polydimethylsilane load in an inert atmosphere in the reactor with a stirrer and heated with stirring to a temperature of 350 - 380oC. At this temperature the decomposition of polydimethylsilane with the formation of gaseous and liquid products, supporting the pressure in the reactor of 1.5 - 6 bar. After treatment for 2 to 10 hours to produce the reset boiling liquid components in the receiver and maintain the reaction mass under continuous stirring at 390 - 450oC for 30 - 80 hours temperature Below 350oaction consobrina components. The reaction products are dissolved in toluene, hexane or other non-polar solvents, insoluble part is separated by centrifugation and filtration. The filtrate is concentrated under atmospheric pressure and a temperature of 70 - 180oC, then a residual pressure of 1 mm RT.article and the temperature in the mass of up to 360oC. Yield of fibre-forming polycarbosilane from download PDMS is 40 - 50%, softening temperature under inert atmosphere - 180-200oC, the temperature of the fiberizing 210 - 2600oC, the content of hydrogen atoms linked to silicon atom, a certain method, synthesized, is 0.65 - 0.75 wt. % share links HSiC3determined by the method of IR-spectroscopy, of 0.68 to 0.75 (Fig. 1).The polymers have a narrow distribution of molecular weight (polydispersity of 1.6 to 2.5). The stable formation test data on the device Roscop" 220 - 260oC.Polycarbosilane obtained by the proposed method consistently are formed on a molding machine of the melt. After heat and heat treatment, the strength of the SiC fibers with a diameter of 8 to 12 microns 270 - 350 kg/mm2.The example for comparison. In a rocking autoclave V = 10 l, equipped with a thermocouple , manometrically, fill it with argon to Pwt.= 100 ATM and heated with stirring to 500oC. as a result of thermal degradation of polydimethylsilane pressure spontaneously increases to 100 ATM. At a temperature of 500oC and a pressure of 100 atmospheres, the reaction mass was kept for 20 hours After cooling, get polycarbosilane (0.8 kg), dissolved in toluene, the solution is lighten by centrifugation and filtration. The number cocoabased sludge amounted to 0.03 kg (3%).After removal of the solvent and low-boiling fractions allocate 0.38 kg (38%) of polycarbosilane with temperatures softening and fiberizing, respectively 190 and 230oC, the content of H atoms with Si atoms to 0.73 wt.% (according to the synthesized) and the relative content of HSiC3groups of 0.50 (according to IR-spectroscopy). The average molecular weight of 780, the number of links n = 6, the polydispersity of 4.0, but the curve of the molecular mass distribution of polycarbosilane obtained by the method of gel permeation chromatography (GPC) (Fig. 1, curve (a)) are high molecular weight components (Mz = 20000). The strength of SiC fibers with a diameter of 15 to 20 μm is 150 to 300 kg/mm2.Example 1. In a standard reactor, equipped with tarmac argon, and nitrogen), load 2 kg of polydimethylsilane and heated under stirring up to 370oC, kept at this temperature for 6 hours, then discharged into the receiver boiling liquid products. Then the temperature was raised to 425oC and kept under stirring for 60 hours the Mass is then cooled, dissolved in toluene, the solution to lighten. The amount of insoluble coke 0.02 kg (1%).After removal of the solvent and low-boiling components at atmospheric pressure and under vacuum at a residual pressure of 1 mm RT.article and the temperature in pairs to 280oC produce 1 kg (50% yield) of polycarbosilane with temperatures softening 190oC and fiberizing 230oC, the content of H atoms with Si of 0.68%, and the share of HSiC30,70. The polydispersity of the polymer is 1.7, Mn = 940, n = 7, Mz = 3100 (Fig. 2, curve b). The area of the molding according to the rheology 220 - 260oC.The formation occurs without breaks and gas. After oxidation and pyrolysis get SiC fibers with a diameter of 8 to 12 microns and an average strength of 270 - 350 kg/mm2.Other examples are given in the table.Thus polycarbosilane synthesized by the proposed method are soluble, fusible polymers that are easily n the C fibers.The method is simple, requires no special equipment and expensive initiating additives.Proceeding from the known views about the process of turning PDMS in the PCB, it was considered impossible to perform a complete thermal rearrangement otherwise than with the use of initiators or high pressure.Obtain this effect it is proposed should be considered by surprise, and the proposed solution meets the criterion of "inventive step". The method of receiving polycarbosilane by thermal decomposition of polydimethylsilane in an inert atmosphere, wherein thermal decomposition is carried out at a gauge pressure of 1.5 - 6 ATM in three stages: exposure at 350 - 380oC for 2 to 10 h, the reset boiling components and subsequent exposure at 390 - 450oWith over 30 - 80 hours
FIELD: chemical technology.
SUBSTANCE: invention describes a method for preparing metallopolycarbosilanes. Method involves interaction of polycarbosilanes with molecular mass above 200 Da and with the main chain consisting of links of the formula: [-(R)2Si-CH2-] wherein R means hydrogen atom (H), (C1-C4)-alkyl or phenyl groups with metalloorganic compounds of the formula MXz wherein M means transient metal of III-VIII group of Periodic system; z = 2-4; X means NR1 2 wherein R1 means (C1-C4)-alkyl group in organic solvent medium at temperatures from 20°C to 400°C under pressure from 5.05 MPa to 0.2 kPA. Method provides preparing fusible soluble polymers with homogeneous distribution of chemically bound metal atoms that elicit high capacity for fiber- and film-formation from solutions or melts that are hardened in thermochemical treatment and provides high yield of ceramic residue in pyrolysis (up to 85 wt.-%).
EFFECT: improved preparing method.
1 tbl, 9 ex
FIELD: organosilicon polymers.
SUBSTANCE: polydimethylsilane is obtained by reaction of dimethyldichlorosilane with sodium at 150-170°C followed by decomposition of unreacted sodium with methyl alcohol, isolation of desired polymer, washing on filter with distilled water, drying on air and the in vacuum. Process is characterized by that sodium reagent is added as deposited on water-soluble solid, incombustible, inorganic substrate.
EFFECT: reduced fire risk of synthesis process and labor intensity of polymer isolation stage.
2 dwg, 1 tbl, 5 ex
FIELD: organosilicon polymers.
SUBSTANCE: novel polycyclic poly- and copolyorganocyclocarbosiloxanes with variable cycle size including structural motif of general formula: , wherein (1) x=3 or 4 and y=1, (2) x=2 and y=2, (3) x=3, and suitable as preceramic templates for manufacturing oxygen-free silicon carbide ceramics are prepared by Würtz reaction in toluene via interaction of chloro-derivatives of organocarbosilanes with metallic sodium in the form of suspension.
EFFECT: enlarged assortment of preceramic templates.
2 cl, 1 tbl, 3 ex
SUBSTANCE: invention relates to field of chemical technology of silicon-organic compounds. Technical task lies in synthesis of novel polyarylsilane links including dendrimers of large generations suitable for application as luminescent materials for organic electronics and photonics. Claimed are dendrimers of general formula (I) where R1 stands for substituent from group: linear or branched C1-C20alkyl groups; linear or branched C1-C20alkyl groups separated by at least one oxygen atom; linear or branched C1-C20 alkyl groups separated by at least one sulphur atom; branched C3-C20 alkyl groups separated by at least one silicon atom; C2-C20alkenyl groups; Ar represents, independently for each n and m, similar or different arylene radicals, selected from group: substituted or non-substituted thienyl-2,5-diyl of general formula (II-a) substituted or non-substituted phenyl-1,4-diyl of general formula (II-b) substituted or non-substituted 1,3-oxazol-2,5-diyl of general formula (II-c) substituted fluorene-4,4'-diyl of general formula (II-d) where R2, R3, R4, R5, R6 represent independently on each other H or said above for R1; R7 stands for said above for R1; K is equal 2 or 3 or 4; L is equal 1 or 3 or 7 or 15; m and n represent whole numbers from series from 2 to 6. Method of obtaining dendrimers lies in the following: monodendron of general formula (III) where X represents H or Br or I, first reacts with lithiumising agent of general formula R8Li, where R8 represents linear or branched C1-C10alkyl group, dialkylamide or phenyl group; then obtained compound reacts with functional compound selected from group of compounds of formula (CH3)4-KSiYK, where Y represents Cl, or Br, or -OCH3, or -OC2H5, or -OC3H7, or -OC4H9. Claimed method is technological, use of expensive catalysts is not required.
EFFECT: elaboration of technological method of synthesising novel polyarylsilane dendrimers which does not require use of expensive catalysts.
24 cl, 12 dwg, 1 tbl, 13 ex
SUBSTANCE: invention relates to novel branched oligoarylsilanes and their synthesis method. The engineering problem is obtaining branched oligoarylsilanes which contain not less than 5 functional arylsilane links and have a set of properties which enable their use as luminescent materials. The disclosed branched oligoarylsilanes have general formula where R denotes a substitute from: straight or branched C1-C20 alkyl groups; straight or branched C1-C20 alkyl groups separated by at least one oxygen atom; straight or branched C1-C20 alkyl groups separated by at least one sulphur atom; branched C3-C20 alkyl groups separated by at least one silicon atom; C2-C20 alkenyl groups; Ar denotes identical or different arylene or heteroarylene radicals selected from: substituted or unsubstituted thienyl-2,5-diyl, substituted or unsubstituted phenyl-1,4-diyl, substituted or unsubstituted 1,3-oxazole-2,5-diyl, substituted fluorene-4,4'-diyl, substituted cyclopentadithiophene-2,7-diyl; Q is a radical selected from the same group as Ar; X is at least one radical selected from the same group as Ar and/or a radical selected from: 2,1,3-benzothiodiazole-4,7-diyl, anthracene-9,10-diyl, 1,3,4-oxadiazole-2,5-diyl, 1-phenyl-2-pyrazoline-3,5-diyl, perylene-3,10-diyl; L equals 1 or 3 or 7 and preferably 1 or 3; n is an integer from 2 to 4; m is an integer from 1 to 3; k is an integer from 1 to 3. The method of obtaining branched oligoarylsilanes involves reaction of a compound of formula where Y is a boric acid residue or its ester or Br or I, under Suzuki reaction conditions with a reagent of formula (IV) A - Xm - A (IV), where A denotes: Br or I, provided that Y denotes a boric acid residue or its ester; or a boric acid residue or its ester, provided that Y denotes Br or I.
EFFECT: obtaining novel compounds distinguished by high luminescence efficiency, efficient intramolecular transfer of energy between molecule fragments and high thermal stability.
24 cl, 12 dwg, 1 tbl, 11 ex
SUBSTANCE: invention relates to macromolecular compounds with a nucleus-shell structure. The invention discloses macromolecular compounds with a nucleus-shell structure, whereby the nucleus has a macromolecular dendritic and hyperbranched structure based on carbon or based on silicon and carbon is bonded to at least three, in particular at least six external atoms through a carbon-based coupling chain (V) which is selected from a group consisting of straight and branched alkylene chains with 2-20 carbon atoms, straight or branched polyoxyalkylene chains, straight or branched siloxane chains or straight or branched carbosilane chains, with straight chains based on carbon oligomeric chains (L) with conjugated double bonds on the entire length. Conjugated chains (L) in each separate case are bonded at the end opposite the coupling chain (V) to one more, specifically, aliphatic, arylaliphatic or oxyaliphatic chain (R) without conjugated double bonds. The chains (V), (L) and (R) form the shell. The invention also discloses a method for synthesis of the said compounds.
EFFECT: novel organic compounds which can be synthesised using conventional solvents and have good semiconductor properties.
16 cl, 2 ex
SUBSTANCE: invention relates to methods of producing polycarbosilanes. Disclosed is a method of producing polycarbosilane via thermal decomposition of polydimethylsilane in the presence of zirconium tetrachloride in an inert atmosphere at excess pressure of 0.4-0.5 MPa in three steps: holding at 350-380°C for 2-10 hours, releasing low-boiling point components and then holding at 350-420°C for 20-30 hours.
EFFECT: method of producing polycarbosilane which enables to cut time and lower temperature of the process.
1 cl, 1 tbl, 1 ex
SUBSTANCE: invention relates to chemical engineering of organosilicon compounds. Disclosed are novel dendronised polyarylsilanes of general formula
, where R denotes a substitute from: linear C1-C12 or branched C3-C20 alkyl groups; linear C1-C12 or branched C3-C20 alkyl groups, separated by at least one oxygen atom; linear C1-C12 or branched C3-C20 alkyl groups, separated by at least one sulphur atom; branched C3-C20 alkyl groups, separated by at least one silicon atom; C2-C20 alkenyl groups; Ar denotes identical or different arylene or heteroarylene radicals selected from: substituted or unsubstituted thienyl-2,5-diiyl; substitured or unsubstituted phenyl-1,4-diiyl, substituted fluorene-4,4'-diiyl. X denotes identical or different arylene or heteroarylene radicals selected from said group for Ar and/or a radical from 2,1,3-benzothiodiazole-4,7-diiyl, anthracene-9,10-diiyl; L equals 0 or a an integer from 1, 3, 7, 15; k is an integer from 1 to 6; m is an integer from 1 to 6; t is an integer from 2 to 10; n is an integer from 5 to 10000. A method of producing said compounds is also disclosed.
EFFECT: synthesis of novel chemical compounds, characterised by high efficiency of luminescence, high molar absorption coefficient and high thermal stability.
SUBSTANCE: invention relates to organic light-emitting diode (OLED) solid-state light sources used to make colour information screens and colour display devices with high consumer properties, as well as cheap and efficient light sources. Disclosed is an OLED, having a base in form of a transparent substrate having a transparent anode layer and a metal cathode layer with a light-emitting layer in between, which is based on a dendronised polyaryl silane of general formula (I) or (II) , where n is an integer from 5 to 1000.
EFFECT: wide range of OLEDs with high operational characteristics, particularly in the radiation range of 400-700 nm, which enables use thereof as light sources.
7 cl, 3 dwg, 6 ex
SUBSTANCE: disclosed are novel branched oligoarylsilanes of general formula (I) , where R denotes a substitute selected from: linear or branched C1-C20 alkyl groups; including separated by at least one oxygen or sulphur atom; branched C3-C20 alkyl groups, separated by at least one silicon atom; C2-C20 alkenyl groups; Ar denotes identical or different arylene or heteroarylene radicals selected from: substituted or unsubstituted thienyl-2,5-diiyl, substituted or unsubstituted phenyl-1,4-diiyl, substituted or unsubstituted 1,3-oxazole-2,5-diiyl, substituted fluorene-4,4'-diiyl, substituted cyclopentadithiophene-2,7-diiyl; Q denotes a radical selected from the series for Ar; X denotes at least one radical selected from the series for Ar and/or a radical selected from: 2,1,3-benzothiiodiazole-4,7-diiyl, anthracene-9,10-diiyl, 1,3,4-oxadiazole-2,5-diiyl, 1-phenyl-2-pyrazoline-3,5-diiyl, perylene-3,10-diiyl; n is an integer from 2 to 4; m is an integer from 1 to 3; k is an integer from 1 to 3. Also disclosed is a method of producing said compounds.
EFFECT: obtaining novel compounds characterised by high luminescence efficiency, efficient intramolecular energy transfer from some molecule fragments to others and high thermal stability.
20 cl, 5 dwg, 1 tbl, 15 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