RU2483085C1 - Polyboron-phenyl siloxanes and method for production thereof - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: disclosed are polyboron-phenyl siloxanes of general formula [(C₆H₅SiO_1.5)_x(BO_1.5)]_n, which contain repeating units:

, where x ranges 2.0 to 3.6; n≥17. Disclosed also is a method of producing said polyboron-phenyl siloxanes, involving reaction of an organosilicon compound with boric acid, characterised by that the organosilicon compound used is polyphenyl siloxane, and synthesis of end products is carried out by mechanochemical activation of a mixture of polyphenyl siloxane and boric acid in molar ratio Si/B from 1:1 to 3:1, frequency of mechanochemical activation of 10 Hz, ratio of the mass of the nozzle to the mass of the payload equal to 1.8, and activation time of 1-5 minutes, followed by separation of the formed polyboron-phenyl siloxanes.

EFFECT: obtaining novel polyboron-phenyl siloxanes with a given ratio and a cheap, environmentally friendly and fast method for production thereof is provided.

9 cl, 9 dwg, 1 tbl, 14 ex

Description

The invention relates to the chemistry of organosilicon compounds, and in particular to the chemistry of boron-containing organosilicon compounds and the method for their preparation; polyborphenylsiloxanes are widely used in various industries.

The increased interest in polyborphenylsiloxanes (PBFS) is due to the prospects for the practical use of these compounds, because the introduction of boron into the structure of polyorganosiloxanes significantly changes their properties.

From the prior art it is known the use of PBFS as modifiers of traditional polymers in order to increase their operational characteristics; upon receipt of anti-corrosion coatings; they are part of heat-resistant adhesives; are used as a binder for synthetic resins and a curing agent for epoxies. The introduction of boron atoms into the siloxane chain enhances the heat resistance and strength of polymers while maintaining high dielectric properties. Such electrical insulating materials, being mechanically strong and resistant to cold and water, can withstand heating in air up to 400 ° C.

The prior art various methods for producing PBFS, which can be divided into two groups:

1. The synthesis of PBFS is carried out in a homogeneous environment using organic solvents.

Known, for example, a method of producing borsiloxane polymers [US patent No. 4152509, publ. 05/01/1979], in accordance with which three moles of diphenyldichlorosilane and a mixture of two moles of boric acid in benzene are stirred for 24 hours in a nitrogen atmosphere at a temperature of 90 ° C. The resulting solution was neutralized with sodium carbonate, the organic layer was separated from the aqueous layer, dried and benzene was distilled off. The resulting white precipitate is heated for one hour under nitrogen at 400 ° C until a polymer forms. Get the product with the General formula [(Ph ₂ SiO) BO _1,5 ] _n and a molecular weight of from 500 to 10000.

A known method of producing polyborsiloxanes characterized by the following formulas [US 2011/0021736, publ. January 27, 2011]:

(ViMe ₂ SiO _0.5 ) _0.7 (BO _1.5 ) _0.25 (SiO ₂ ) _0.05 ,

(BO _1.5 ) _0.15 (MeSiO) _0.55 (PhSiO _1.5 ) _0.3 ,

(PhBO) _0.15 (PhBO _0.5 (OH)) _0.03 (PhSiO _1.5 ) _0.31 (PhSiO (OH)) _0.51 and others.

According to this method, a mixture of iron (III) chloride and dimethyldichlorosilane in a nitrogen atmosphere at 50 ° C. is added to trimethyl borate with stirring for 1 hour. Then, solutions of haloalkyl (aryl) silanes in toluene are added to the obtained intermediate product, followed by hydrolysis of the obtained compounds.

In the invention [patent US 6784270, publ. 08/31/2004] a method for producing polyborsiloxanes by the interaction of polyacetylenesiloxane with boric acid in various molar ratios in tetrahydrofuran medium is described.

The disadvantages of these methods are the high temperature and duration of the synthesis, the need to use an inert atmosphere (for example, nitrogen), the use of organic solvents (including flammable and toxic), the preparation of compounds with a low boron content due to side processes of hydrolysis of the borsiloxane bond.

2. Methods for producing PBFS in a heterogeneous medium, followed by extraction of boron-containing organosilicon compounds.

The advantages of this group of methods are simplicity and short time of their implementation, the absence of solvents at the stage of synthesis.

The closest analogue to the claimed method for producing PBFS according to the set of essential features and the achieved result is a method for producing polybordiphenylsiloxanes, in which these compounds are obtained by the interaction of diphenylsilanediol and boric acid, taken in a molar ratio of Si / B equal to from 1: 2 to 2: 3 [patent US No. 4228270, publ. 10/14/1980]. The synthesis is carried out in the absence of solvent at a temperature of from 80 to 140 ° C. The mixture of diphenylsilanediol and boric acid in a predetermined ratio is triturated in an agate mortar and mixed; the mixture is placed in a flask, heated for 20 minutes to 100 ° C and maintained at this temperature for two hours. A white solid product is obtained with the following structural fragments: (-OBX-O-Si (Ph) ₂ -O-Si (Ph) ₂ -O-) n, where X is hydrogen or -Si (Ph) ₂ O (H) group, and an average molecular weight of from 500 to 5000.

The synthesis of polybordiphenylsiloxanes in accordance with the prototype is based on the dehydration reaction:

where Ph is phenyl.

A similar product was obtained in the solid phase in a nitrogen atmosphere at a temperature of from 250 to 400 ° C.

Despite the fact that the synthesis is carried out in the absence of solvents, this method has several disadvantages: the high cost of the starting diphenylsilanediol, high synthesis temperatures, the duration of the process, and the use of a nitrogen atmosphere. These disadvantages reduce the manufacturability and efficiency of the method.

The task of the invention is to expand the range of PBFS through the synthesis of new boron-containing organosilicon compounds, as well as the development of a method for their preparation.

The problem is solved by the synthesis of new PBFS with different Si / B ratios - new boron-containing organosilicon compounds are obtained:

[(PhSiO _1.5 ) _2.0 BO _1.5 ] _n ; [(PhSiO _1.5 ) _2.1 BO _1.5 ] _n ; [(PhSiO _1.5 ) _2.2 BO _1.5 ] _n ;

[(PhSiO _1.5 ) _2.3 BO _1.5 ] _n ; [(PhSiO _1.5 ) _3.2 BO _1.5 ] _n ; [(PhSiO _1.5 ) _3.4 BO _1.5 ] _n ;

[(PhSiO _1.5 ) _3.6 BO _1.5 ] _n ,

where Ph is C ₆ H ₅ , n≥17.

The problem is also solved by the proposed environmentally friendly and more economical way to obtain PBFS, including the interaction of polyphenylsiloxane (PPS) and boric acid under conditions of mechanochemical activation.

The problem is solved in the optimal way by preliminary obtaining PPS according to the standard method and the subsequent mechanochemical reaction of the interaction between polyphenylsiloxane and boric acid with an initial Si / B molar ratio varying from 1: 1 to 3: 1, activation time 1-5 minutes, and frequency of mechanochemical activation 10 Hz The synthesis of PBFS is carried out at room temperature, in the absence of solvents, with a ratio of the mass of the nozzle to the mass of the payload in the syntheses of 1.8.

Thus, the technical result of the claimed invention is the development of an environmentally friendly, economical and quick method for producing previously unknown organosilicon boron compounds of a given composition.

An analysis of the reaction products by various physicochemical methods showed that during the mechanochemical synthesis, the interaction of PPS and boric acid probably occurs according to the following scheme:

x (C ₆ H ₅ SiO _1,5 ) _n + nH ₃ BO ₃ → [(C ₆ H ₅ SiO _1.5 ) _x (BO _1.5 )] _n + 1.5nH ₂ O,

where x is from 2.0 to 3.6; n≥17.

The method of synthesis of new PBFS is as follows. Initially, according to a known method [Andrianov K.A., Khananashvili L.M. Technology of organoelement monomers and polymers. - M .: Chemistry, 1973. - 400 S.] get polyphenylsiloxane. Next, solid-state synthesis of PBFS is carried out; for this purpose, the specified amounts of PPS and boric acid are placed in the Pulverisette 6 planetary mill mill, with the initial Si / B molar ratio varying from 1: 1 to 3: 1. Mechanochemical activation is carried out at a frequency of 10 Hz, the activation time from 1 to 5 minutes and the ratio of the mass of the nozzle to the mass of the payload in the synthesis of 1.8.

The resulting products are gray powders from which the desired PBFS is recovered using their good solubility in organic solvents, in particular toluene. Extraction is carried out in a Soxhlet apparatus; the end of the extraction is judged by the termination of the reduction in the mass of the soluble fraction. Next, the solvent is distilled off from the soluble fraction, first dried in air for 2 hours, and then in a vacuum oven at a temperature of 75 ° C to constant weight.

New polymer products are obtained that are readily soluble in organic solvents and are glassy substances of white and pale yellow color with a molecular weight of ≥5000, and the structural formula of fragments of polyphenylsiloxanes:

The General formula obtained according to the claimed invention PBFS - [(C ₆ H ₅ SiO _1,5 ) _x (BO _1,5 )] _n , where x is from 2.0 to 3.6; n≥17.

The resulting new organosilicon boron compounds were studied by IR spectroscopy, gel permeation chromatography, and also by means of x-ray phase and elemental analysis; research data are presented in figures 1-9 and in the table.

IR spectra were recorded on a HEWLETT PACKARD Series 1110 MSD spectrometer in the region of 4000-400 cm ^-1 in potassium bromide.

X-ray phase analysis was performed on a Bruker-AXS "D8" Advanced instrument.

Gel permeation chromatography was performed on a column 980 mm long, 12 mm in diameter, filled with a copolymer of polystyrene and 4% divinylbenzene with a grain diameter of 0.08-1 mm and a flow rate of 1 ml / min; toluene served as eluent.

Data gel permeation chromatography (figure 1) indicate that the resulting substances are polymers, because the composition of the soluble fractions of syntheses 2-14 do not include low molecular weight compounds; the molecular weight of the obtained polymers is> 5000.

The structure and structure of the synthesized polymers are confirmed by the data of IR spectroscopy, elemental and x-ray phase analysis. The IR spectra of the soluble fractions of all the syntheses (examples 2-14) contain signals in the region of 1430 cm ^-1 corresponding to the vibration of the Si - C ₆ H ₅ bond in siloxanes and 1130 cm ^-1 corresponding to the vibration of the Si - C ₆ H ₅ bond in silsesquioxanes (figure 2, 4, 6, 8). The band in the region of 1000-1100 cm ^-1 corresponds to vibrations of the Si-O-Si bond (FIGS. 2, 4, 6, 8). The> B-O bond in the B-O-Si fragment manifests itself in the region of 1360 cm ^-1 , while the characteristic band becomes more intense with an increase in the boron content in polyborphenylsiloxanes from 0.3 to 4.1 (examples 2-7, 9-14 2, 4, 6, 8). In addition, in the IR spectra there are bands corresponding to stretching vibrations of CH bonds in the region of 3100-3000 cm ^-1 and vibrations of the C = C bond of the benzene nucleus in the region of 1595 cm ^-1 . All experimental data of physical and chemical studies are in good agreement with published data.

Information about the popularity of new PBFS of the above composition from the prior art is not revealed.

It was experimentally established that the proposed mechanochemical method for producing new PBFS can be implemented at different molar Si / B ratios, different activation times, and different ratios of nozzle mass to payload mass at a mechanochemical activation frequency of 10 Hz and at room temperature.

Examples (2-7) show the effect of the composition of synthesized PBFS depending on the Si / B ratio. The data obtained allow us to conclude that the most optimal initial Si / B molar ratio is 2: 1. It is with this ratio that the products of a given composition are obtained, with a rather high boron content (examples 5, 6, 7). With an initial Si / B molar ratio of 1: 1, part of the boric acid does not react; thus, an inappropriate expenditure of the starting boric acid occurs (examples 2, 3, 4).

The selection of the optimal ratio of nozzle mass to payload mass is also based on experimental results. It was shown that a change in this parameter from 1.8 to 3.04 with the same other factors of the proposed method for the synthesis of PBFS leads to a decrease in the boron content in the polymer chain, increasing the proportion of unreacted boric acid (examples 12, 13, 14). According to published data, this may be due to partial destruction of products with an increase in load (EA Talashkevich. Preparation of polymetallorganosiloxanes by the method of mechanochemical activation and study of their properties. Diss. For the degree of candidate of chemical sciences, Vladivostok, 2000 - 136 p.) .

The optimal time of mechanochemical activation was determined experimentally, namely 3-5 minutes (examples 3, 4, 6, 7, 10, 11). An increase in activation time of more than 5 minutes (up to 7 minutes) is impractical because leads to the extraction of boron from the polymer chain (example 8).

The inventive mechanochemical method for producing PBFS with a given Si / B ratio has the following significant distinguishing features in comparison with the prototype:

- synthesis is carried out in the absence of solvents, namely, by means of mechanochemical activation of the starting reagents at room temperature;

- the method allows to obtain new, previously not known from the prior art PBFS with a given ratio of Si / B;

- significantly reduced synthesis time;

- affordable and inexpensive starting compounds are used.

Distinctive features, together with the known ones, provide the claimed solution with a new technical property, which consists in intensifying the synthesis method of PBFS of the general formula [(C ₆ H ₅ SiO _1.5 ) _x (BO _1.5 )] _n , where x is from 2.0 to 3.6; n≥17.

The proposed method allows to obtain organosilicon boron compounds of a given composition, as well as to reduce the process time, increase its environmental friendliness and economy due to the lack of the need for organic solvents, high temperatures and expensive starting compounds.

Based on the foregoing, it can be concluded that the set of essential features of the claimed invention has a causal relationship with the achieved technical result, and the above distinguishing features are not found in available sources of information.

The possibility of carrying out the claimed invention is confirmed by examples.

Example 1

Obtaining the original polyphenylsiloxane.

The synthesis was carried out according to the known method [Andrianov K.A., Khananashvili L.M. Technology of organoelement monomers and polymers. - M .: Chemistry, 1973. - 400 p.].

A solution of 100.75 g (0.5 mol) of phenyltrichlorosilane in 150 ml of sulfuric ether was added dropwise to a mixture of 150 ml of sulfuric ether and 250 ml of distilled water in a 1 L flask equipped with a mechanical stirrer and reflux condenser. The synthesis was carried out with constant cooling of the flask to minus 20 ° C and vigorous stirring for one hour.

The organic ether layer was separated on a separatory funnel, washed with distilled water until neutral, and dried over anhydrous sodium sulfate (20 g Na ₂ SO ₄ ) for a day. The ether was distilled off by heating the mixture in a water bath, and at the final stage a vacuum was created using a water-jet pump. The product was dried in a vacuum oven at 80 ° C.

Received 56.5 g of PPS (86.8%). Identification and purity of the product is confirmed by data of elemental and x-ray phase analysis, data of infrared spectroscopy. Received PPS [C ₆ H ₅ SiO _1.5 · 0.17H ₂ O] _n , found: Si 21.2%, C 54.5%; calculated: Si 21.2%, C 54.5%.

In Examples 2-14, pre-prepared toluene and boric acid were used. For this, toluene was preliminarily dried with sodium, distilled and a fraction was taken at temperatures of 110-111 ° С; boric acid was recrystallized from water (t _PL = 171 ° C).

Example 2

Synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _2.1 BO _1.5 ] _n at a molar ratio Si / B equal to 1: 1.

0.05 mol (6.6 g) of polyphenylsiloxane and 0.05 mol (3.1 g) of boric acid were placed in the Pulverisette 6 planetary mill. Mechanochemical activation was carried out at a frequency of 10 Hz for 1 minute and the ratio of the mass of the nozzle to the mass of the payload equal to 1.8. A gray powder was obtained, from which the synthesized polyborphenylsiloxane was recovered by toluene extraction in a Soxhlet apparatus. The end of the extraction was judged by the termination of the reduction in mass of the insoluble fraction. Then, toluene was distilled off from the soluble fraction, dried in air for two hours, and then in a vacuum oven at a temperature of 75 ° C to constant weight.

Received PBFS with the general formula [(PhSiO _1.5 ) _2.1 BO _1.5 ] _n , where n = 21 (Mr = 6500); the yield of the target product was 6.59 g (67.9%). The density of PBFS is 1.23299 g / ml, d ₁ = 11.30 Å (2Θ = 8.3), d ₂ = 4.57 Å (2Θ = 19.4). The IR spectrum and x-ray phase analysis are presented in figures 2, 3, respectively; the table shows the data of elemental analysis.

Example 3

The synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _2.1 BO _1.5 ] _n at a molar ratio Si / B of 1: 1 was carried out according to Example 2, but with an activation time of 3 minutes.

Received PBFS with the general formula [(PhSiO _1.5 ) _2.1 BO _1.5 ] _n , where n = 21 (Mr = 6500); the yield of the target product was 6.83 g (70.4%). The density of PBFS is 1,2007 g / ml, d ₁ = 11.44 Å (2Θ = 8.3), d ₂ = 4.64 Å (2Θ = 19.0). The IR spectrum and x-ray phase analysis are presented in figures 2, 3, respectively; the table shows the data of elemental analysis of the obtained PBFS.

Example 4

The synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) ₂ BO _1.5 ] _n at a molar ratio Si / B of 1: 1 was carried out according to examples 2, 3, but with an activation time of 5 minutes.

Received PBFS with the general formula [(PhSiO _1.5 ) ₂ BO _1.5 ] _n , where n = 17 (Mr = 5000); the yield of the target product was 6.9 g (71.2%). The density of PBFS is 1.1845 g / ml, d ₁ = 11.55 Å (2Θ = 8.3), d ₂ = 4.72 Å (2Θ = 18.8). The IR spectrum and x-ray phase analysis are presented in figures 2, 3, respectively; data of elemental analysis of the obtained PBFS are presented in the table.

Example 5

Synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _2.3 BO _1.5 ] _n at a molar ratio Si / B of 2: 1.

Obtaining the target product was carried out as in example 2, but with a Si / B ratio of 2: 1. 0.05 mol (6.6 g) of polyphenylsiloxane and 0.025 mol (1.55 g) of boric acid were placed in the Pulverisette 6 planetary mill. Received PBFS with the general formula [(PhSiO _1.5 ) _2,3 BO _1.5 ] _n , where n = 20 (Mr = 6500); the yield of the target product was 7.1 g (87.1%). The density of PBFS is 1.2807 g / ml, d ₁ = 11.55 Å (2Θ = 8.3), d ₂ = 4.595 Å (2Θ = 19.4), d ₃ = 3.169 Å (2Θ = 28.2) . The IR spectrum and x-ray phase analysis are presented in figures 4, 5, respectively; the table shows the data of elemental analysis of the target product.

Example 6

The synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _{2, .2} BO _1.5 ] _n at a Si / B molar ratio of 2: 1 was carried out according to Example 5, but with an activation time of 3 minutes.

Received PBFS with the general formula [(PhSiO _1.5 ) _2.2 BO _1.5 ] _n , where n = 20 (Mr = 6500); the yield of the target product was 7.47 g (91.6%). The density of PBFS is 1.2563 g / ml, d ₁ = 11.28 Å (2Θ = 8.3), d ₂ = 4.599 Å (2Θ = 19.4), d ₃ = 3.174 Å (2Θ = 28.2). The IR spectrum and x-ray phase analysis are presented in figures 4-5, respectively; the table shows the data of elemental analysis of the synthesized PBFS.

Example 7

The synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _2.2 BO _1.5 ] _n at a molar ratio of Si / B equal to 2: 1 was carried out according to examples 5, 6, but with an activation time of 5 minutes.

Received PBFS with the general formula [(PhSiO _1.5 ) _2.2 BO _1.5 ] _n , where n = 20 (Mr = 6500); the yield of the target product was 7.36 g (90.3%). The density of PBFS is 1.2422 g / ml, d ₁ = 11.00 Å (2Θ = 8.3), d ₂ = 4.533 Å (2Θ = 19.4), d ₃ = 3.174 Å (2Θ = 28.2) . The IR spectrum and x-ray phase analysis are presented in figures 4, 5, respectively; the table shows the data of elemental analysis of the synthesized PBFS.

Example 8

The synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _23.8 BO _1.5 ] _n at a molar ratio of Si / B equal to 2: 1 was carried out according to examples 5, 6, 7, but with an activation time of 7 minutes.

Received PBFS with the General formula [(PhSiO _1.5 ) _23.8 BO _1.5 ] _n ; the yield of the target product was 6.78 g (83.1%). For PBFS: d ₁ = 11.47 Å (2Θ = 8.3), d ₂ = 4.44 Å (2Θ = 19.4). The IR spectrum and x-ray phase analysis are presented in figures 4, 5, respectively; the table shows the data of elemental analysis of the target product.

Example 9

Synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _3.6 BO _1.5 ] _n at a molar ratio Si / B of 3: 1.

The preparation of the target product was carried out as in Example 2, but 0.15 mol (19.8 g) of polyphenylsiloxane and 0.05 mol (3.1 g) of boric acid were placed in the Pulverisette 6 planetary mill; the molar ratio of Si / B was 3: 1. Received PBFS with the general formula [(PhSiO _1.5 ) _3.6 VO _1.5 ] _n , where n = 17 (Mr = 8500); the yield of the target product was 21.1 g (92.0%). The density of PBFS is 1.2557 g / ml, d ₁ = 11.73 Å (2Θ = 8.3), d ₂ = 4.72 Å (2Θ = 19.0). The IR spectrum and x-ray phase analysis are presented in figures 6, 7, respectively; the table shows the data of elemental analysis of the obtained PBFS.

Example 10

The synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _3.2 BO _1.5 ] _n at a molar ratio Si / B of 3: 1 was carried out according to example 9, but with an activation time of 3 minutes. Received PBFS with the general formula [(PhSiO _1.5 ) _3.2 BO _1.5 ] _n , where n = 19 (Mr = 8500); the yield of the target product was 21.48 g (93.8%). The density of PBFS is 1.2327 g / ml, d ₁ = 11.62 Å (2Θ = 8.3), d ₂ = 4.66 Å (2Θ = 19.0); The IR spectrum and x-ray phase analysis are presented in figures 6, 7, respectively; the table shows the data of elemental analysis.

Example 11

The synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _3.4 BO _1.5 ] _n at a molar ratio Si / B of 3: 1 was carried out according to examples 9, 10, but with an activation time of 5 minutes. Received PBFS with the general formula [(PhSiO _1.5 ) _3.4 BO _1.5 ] _n , where n = 18 (Mr = 8500); the yield of the target product was 21.2 g (92.5%). The density of PBFS is 1.2630 g / ml, d ₁ = 11.72 Å (2Θ = 8.3), d ₂ = 4.44 ((2Θ = 19.0); The IR spectrum and x-ray phase analysis are presented in figures 6, 7, respectively; the table shows the data of elemental analysis.

The mechanochemical synthesis of PBFS described in examples 12-14 was carried out analogously to examples 5-7, i.e. with a Si / B ratio of 2: 1, but the ratio of nozzle mass to payload mass was 3.04.

Example 12

Synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _8.5 BO _1.5 ] _n at a Si / B molar ratio of 2: 1 and an activation time of 1 minute.

The synthesis of the target product was carried out analogously to example 5, i.e. with a molar ratio of Si / B equal to 2: 1, activation time equal to 1 minute; but the ratio of nozzle mass to payload mass was 3.04. Received PBFS with the General formula [(PhSiO _1.5 ) _8.5 BO _1.5 ] _n ; the yield of the target product was 6.77 g (83.1%). The density of PBFS is 1.0217 g / ml, d ₁ = 11.33 Å (2Θ = 8.3), d ₂ = 4.6680 Å (2Θ = 19.4); The IR spectrum and x-ray phase analysis are presented in figures 8, 9, respectively; elemental analysis data are given in the table.

Example 13

Synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _28.3 BO _1.5 ] _n at a Si / B molar ratio of 2: 1 and an activation time of 3 minutes.

The synthesis of the target product was carried out analogously to example 12, but the activation time was 3 minutes. A compound of the composition [(PhSiO _1.5 ) _28.3 BO _1.5 ] _n ; the yield of the target product was 4.99 g (61.18%); the density of PBFS is 0.7236 g / ml, d ₁ = 11.77 Å (2Θ = 8.3), d ₂ = 4.6312 Å (2Θ = 19.4); The IR spectrum and x-ray phase analysis are presented in figures 8, 9, respectively; the data of elemental analysis of the target product are given in the table.

Example 14

Synthesis of polyborphenylsiloxane [(PhSiO _1.5 ) _24.3 BO _1.5 ] _n at a Si / B molar ratio of 2: 1 and an activation time of 5 minutes.

The synthesis of the target product was carried out analogously to examples 12, 13, but the time of mechanochemical activation was 5 minutes. Received PBFS with the General formula [(PhSiO _1.5 ) _24.3 BO _1.5 ] _n ; the yield of the target product was 5.92 g (72.7%); the density of PBFS is -1.2557 g / ml, d ₁ = 11.83 Å (2Θ = 8.3), d ₂ = 4.5917 Å (2Θ = 19.4); The IR spectrum and x-ray phase analysis are presented in figures 8, 9, respectively; elemental composition data are given in the table.

Claims (6)

1. Polyborphenylsiloxanes with the general formula [(C ₆ H ₅ SiO _1.5 ) _x (BO _1.5 )] _n , containing repeating units of the formula:

where x is from 2.0 to 3.6; n is ≥17. 2. The method of producing polybiphenylsiloxanes according to claim 1, comprising reacting an organosilicon compound with boric acid, characterized in that polyphenylsiloxane is used as an organosilicon compound, and the synthesis of the target products is carried out by mechanochemical activation of a mixture of polyphenylsiloxane and boric acid at a Si / B molar ratio in the range from 1: 1 to 3: 1, the frequency of mechanochemical activation of 10 Hz, the ratio of the mass of the nozzle to the mass of the payload equal to 1, 8, and the activation time of 1-5 minutes, followed by isolation polyborphenylsiloxanes formed. 3. The method according to claim 2, characterized in that the polyphenylsiloxane is pre-synthesized by hydrolysis of phenyltrichlorosilane and subsequent polycondensation of the hydrolysis product. 4. The method according to claim 2, characterized in that the mechanochemical activation is carried out at room temperature in the absence of organic solvents. 5. The method according to claim 2, characterized in that the separation of polyborphenylsiloxanes and by-products of the solid-phase reaction is carried out by extraction of the target products with an organic solvent, in particular toluene, after which the solvent is distilled off and the products are dried to constant weight. 6. The method according to claim 5, characterized in that the products are dried at the beginning in air for two hours, and then in a vacuum oven at a temperature of no higher than 75 ° C.

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