SU1634674A1 - Method of producing polysiloxane urethanes - Google Patents

Description

(21) 4367931/05

(22) 01.22.88

(46) 03/15/91. Bul Number 10

(71) Moscow Institute of Chemical Technology. D.I. Mendeleeva and the State Research Institute of Chemistry and Technology of Elemental Organizations

(72) A.R.Korigodsky, V.M. Kopylov, D.F. Kutepov, O.V. Arinushkina,

M.I. Shkolnik, A.F. Fedotov, A.V.Tara-.

owls, S.I. Smirnov, V.M.Sydorenko,

N.P. Bessonova, Yu.K.Godovskii,

V.D. Sheludov and G.V.Sin

(53) 678.664 (088.8)

(56) USSR author's certificate

No. 998469, cl. C 08 G 18/61, 1981.

(54) METHOD OF OBTAINING POLYLILOXANE URETHANES

(57) The invention relates to the production of polysiloxanurethanes (PPS) suitable for use as a material in the manufacture of gas separating membranes (GM), and can be used in various industries. The invention makes it possible to increase the gas permeability of GM through the use of a low molecular weight diol and oligodimethylsiloxane diol and an aromatic diisocyanate in the synthesis of PSP as a low molecular weight diol 1,3-bis (hydroxymethyl) tetramethyl disiloxane. Synthesis is carried out. in the medium of an aprotic solvent at 50-90 ° C, tin dibutyldilurinate is used as a catalyst for the reaction. 3 tab.

J

(L

The invention relates to the technology of producing silicon-containing polymers, in particular, to a method for producing polysiloxanurethanes, which are suitable as materials for gas separation membranes, and can be used in various industries.

CHi and he np

i 6 i and i i c

-OCH2StOSiCH7OCN-R-NC

CH3 CH3

The aim of the invention is to increase the gas permeability of polysipoxanurethane-based membranes.

According to the invention, polysiloxanurethanes of the general formula are obtained:

CH, CH3OH BUT

I 3 IIII and

-0 (CH2) tnSi (OSi) n (CH2) mOCN-R-NCo

WITH

-U

about

vj

four

x1

CH3 CH-j

yJ

sn3;

where r

m is equal to n

x is 1-2;

y is 1-2.

Carbo-functional oligodimethylsiloxane diols (ODS), - (, CO-bis (hydroxymethyl) - and #, 03 -bis (3-hydroxypropyl) oligodimethylsiloxane are used in the synthesis of polysiloxane urethanes. Their molecular weight is 790-1500.

According to this method, 1,3-bis (hydroxymethyl) -tetramethyldisiloxane is used as a low molecular weight diol for the synthesis of polysiloxane urethanes - starting material for the preparation of the first of the mentioned oligomers. This diol has a high reactivity when interacting with diisocyanates and is an affordable product.

 The isolation of the polymer from the reaction medium is carried out by evaporation of the solvent or by precipitation in a precipitant, for example, in water.

The synthesized polysiloxanurethanes have good solubility in a wide range of organic solvents (chlorinated hydrocarbons, ketones, esters, amide solvents). Elastic film materials are obtained from their solution in volatile solvents.

The structure and composition of the synthesized polysiloxanurethanes is confirmed by the data of elemental analysis, PMR and IR spectroscopy. In the IR spectra, the characteristic swallowing bands are identified, corresponding to the vibrations of the CN (1350, 1300), M – H (3340–3320), (1730), C-0 (1080– 1060 cm – 1) bonds urethane group; С-Н in apifatic groups (2960, 2870); C-H in aromatic groups (770 cm); 51-0 (1050-1020), Si-C (1260, 820-810 cm) in dimethylsiloxane groups.

Example. In a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a tube for injecting argon, 0.737 g (3.800 10 emols) of 1,3-bis (gndroxymethyl) tetramethyl disiloxane are placed; 6.005 g

(7,601 1SG3 mol) oligodimethylsiloxane diol (t 1; n 9; MM 790), 2,850 (P, 40210 mol) 4,4-dtenilmetanedi-isocyanate and 12 ml of freshly distilled dioxane. The reaction mixture is heated to 80 ° C, a solution of 0.0017 g of tin dibutyldyl laurinate dissolved in 3 ml of dioxane is added to it and kept at this temperature for 3 hours. After completion of the reaction, the contents of the flask are cooled, diluted with dioxane h and planted in distilled water The polymer obtained is filtered and dried in vacuo at 50 ° C until constant weight. The polymer yield is 9.2 g (96.1% of theoretical yield); reduced viscosity

pr 0.38 dl / r. Elemental analysis data (Si).

Calculated,%: 24.40.

Found,%: 24.01.

Tables 1 and 2 show examples of syntheses and the main characteristics of polysiloxanurethanes (examples 1-4) according to a method similar to the one given.

Film samples for testing were prepared by pouring from a solution (10% solution of polymers in chloroform) and are 80 µm thick.

Table 3 presents the results of tests of gas separation membranes based on the proposed polysiloxanurethanes containing silicone fragments in rigid and elastic blocks. The gas permeability coefficients are determined by the chromatographic method at 25 ° C.

Claims (1)

Invention Formula A process for preparing polisiloksanuretanov by reacting a mixture of a low molecular weight diol and oligodi- metilsiloksandiola with an aromatic diisocyanate in an aprotic solvent medium at 50-90 ° C prisust- Corollary dibutildilauritana tin, characterized in that, in order to increase the gas permeability through membranes fabricated polisiloksanuretanov as low molecular weight diol is used 1,3-big (hydroxymethyl) tetramethyldisiloxane. Determined for a 0.5% solution in dioxane at 25 ° C. Calculated Table 3 Table 1 7.601 6.005-CH2- - 402., 850 13,970 3,492 8,204 2,051  6,400 2,853 eggs 2