SU1141096A1 - Esters of mono- and diphenyl-(4-hydroxy-3,5-di-tert-butylphenyl) methylphosphonic acid as thermal stabilizers of impact-proof polystyrene - Google Patents

Abstract

Mono- and diphenyl- (4-hydroxy-3, 5-di-tert-butylphenyl) methylphosphonic acid esters of the general formula Chead. t- P

Description

; O 0)

1I

 This invention relates to the chemistry of phosphorogropic intermediates with the C-P bond, namely, to new compounds, mono- and diphenyl- (4-hydroxy-3, 5-di-tert-butylphenyl) methyl phosphonic acid esters of the general formula

C (SNS).

C & H5

/ ch

sr (a) {s) 5

B

С (СНз)

-%

 R is phenyl; , R is methyl or ethyl; R-- hydrogen; R is methyl, which can be used as thermostabilizers of high impact polystyrene.

It is known to use tri (p-nonylphenyl) phosphite (phosphite NP) as a heat stabilizer for impact-resistant polystyrene ij.

However, this compound has a low thermostabilizing effect and is hydrolyzed during storage.

The structure closest to the invention is 4-hydroxy-355-di-tert-butylbenzylphosphonic acid dimethyl ester, which can be used to stabilize organic polymeric materials 2.

However, the known compound has a low thermostabilizing effect.

The aim of the invention is to increase the efficiency of heat stabilizers for high impact polystyrene.

This goal is achieved by new compounds - mono-di-1-sh- (4-hydroxy-3,5-di-tert-butylphenyl) methylphosphonic acid esters of the general formula II, which can be used as heat stabilizers for impact polystyrene.

These compounds have a high thermostabilizing activity and, however, of all their effectiveness, they are significantly superior to the known stabilizer phosphite PF.

Mononon diphenyl (4-hydroxy, 5-di-tert-butylphenyl) methylphosphonic acid esters () are obtained by the interaction of the corresponding methylenequinone

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with dialkylphosphite in the presence of a miner. acid as a catalyst.

The new compounds are 5 colorless crystalline substances with distinct melting points, insoluble in water, petroleum ether, and soluble in acetone, alcohols, and benzene. Structure

The 10 compounds obtained confirm that the IR and HMR spectroscopy data is unequivocally confirmed. In addition to the elemental analysis, the IR spectra of the compounds obtained contain absorption bands.

15 OH groups (3400-3600), РО. (1220-1250 cm) and СОР (10301070 cm), The position and intensity of proton signals in the PMR spectra of the described compounds corresponds to the given structural formulas. Example 1 Preparation of Diphenyl- (4-hydroxy3, 5-n-t-butylphenyl) methylphosphonic acid dimethyl ester,

5 In a flask with a capacity of 0.25 l, equipped with a mechanical stirrer and a reflux condenser, 24.8 g (0.067 mol1) of 4-diphenyl-methylene-2, 6-di-tert-butyl -2, 5-cyclohex0 sadien-1- are charged. she and 27.2 g (0.25 mol), dimethylphosphite. Upon completion of loading, stirring is included and the reaction mixture is heated until complete dissolution, melene quinone, and then 10-20 drops of condensed sulfuric acid are added through a reflux condenser. The mixture is maintained at a bath temperature of 130. 140 ° C until decolorization (6-8 hours) Q and cooled to. Excess phosphite is distilled off in vacuum. The residue is crystallized from petroleum ether and acetone. Get 21,3 dimethyl ether diphenyl- (4-hydroxy5 3,5 di-tert-butylphenyl) methylphosphonic acid (1, R - ,,), Yield 68%,

I- v and

IR spectrum (table, KBG, v, cm):

1050 (COP); 1240 (); 3480 (OH), 0 NMR spectrum (solution in B acetone;

SG, m, d,): 1.25, s, (C-CHj); 3.4 d, (O-CH-3), 1 (nsoR) 10.5 Hz; 4.9 m, (OH); 7.1 m, aromatic protons, T, mp, 187-187 ,, 5Found,%: C 71.88; And 7.18;

R 6.34,

Num,%: C, 72.48; IJ 7.76; P 6.44,

Example 2 Preparation of diphenyl- (4-hydroxn3, 5-di-tert-butylphenyl) methylphosphonic acid diethyl ester.

In the conditions of example 1 out of 25.9 g (0.07 mol) 4-difensh1metilen-25b-. di-tert-butyl-255-cyclohexadiene-1one and 20 g (0.3 mol) of diethylphosphite receive 25.0 g of diethyl ether diphenyl- (4-hydroxy-3, 5-di-tert-betsh1fergil) methylphosphonic acid (1, R CgHj , R C2H) in the form of colorless crystals with so pl. 213-214 ° C (from acetone). Yield 54%.

IR spectrum (table.KVg; cm): 1050 (COP); 1230 (P O); 3560 (OH)

PMR spectrum (solution in CC14, ppm): 0.99, t, (CN), 1 (nssn1, 7 Hz | 1.25, s, ((C11h) s –C); 3.72, m, (); .7,13, m, aromatic colors, tones.

Found,%: C 72.10; Ы 8.26; P 6.15.

Calculated,%: C, 72.20; H 8.12; R 6.08.

Example 3. Preparation of phenyl- (4-hydroxy-3, 5di-tert-butylphenyl) methylphosphonic acid dimethyl ester.

Under the conditions of Example 1, out of 3.0 g (0.01 mol) of 4-benzylidene-2,6-di-tert-butyl-2, 5-cyclohexadiene-1 and 3.3 g (0.03 mol) of dimethylphos (1) It gives 3.1 g of phenyl- (4-hydroxy-3, 5-di-tert-butylphenyl) methylphosphonic acid dimethyl ester (I, R H, R SPr as colorless crystals with mp 132 -. 133 C (from a mixture hexane: acetone 10: 1). 75% yield.

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IR spectrum (table.KVg-;

cm-m:

1040-1070 (COP) 1250 (); 3450 (OH).

PMR spectrum solution in D-acetone; s, ppm) 1 1.33, s, (C-CH); 3.4 d (0-CH3),) 10 Hz; 4.4 d, (PrCHj, 1 (HOP) 25 Hz; 6.0, s, (he); 7.2, m, aromatic protons. Found,%: C 67.82; H 8.03; P 8 , 00.

Calculated,%: C 68.29; H 8.22; R 7.66.

The synthesized compounds were tested as heat stabilizers of impact-resistant polystyrene of the USh1-0503 brand.

Prepare a composition consisting of UPM-0503 high impact polystyrene and a stabilizing additive in the amount of 0.5 parts by weight.

A 5% benzene solution is prepared from the resulting composition. After the polymer and stabilizer are completely dissolved in benzene, films are cast by pouring onto a cellophane substrate bounded by a glass circle.

Films with a thickness of 70 µm are subjected to thermal aging at air, followed by sampling and removal of the IR spectra, absorption in the region of 1600–1900 cm, the characteristic absorption band of the groups at I720 cm and in the region of 800–1000 cm (characteristic absorption band of the bonds at 967 cm).

The data obtained are shown in the table.

- cs 7 Thus, compared to the phosphite NF used in practice as a stabilizer, as well as the structural analogue of new compounds, the latter possess significantly more than 11,41096. 8 more high thermal stabilizing activity. Polymer films are not stained during the aging process and retain their original elasticity.