RU2100360C1 - Products of oligomerization of 10-propenyl phenothiazine as stabilizing agent for polyolefins - Google Patents

Abstract

FIELD: production of stabilized polymer compositions. SUBSTANCE: products of oligomerization of 10-propenyl phenothiazine having common formula $$$ where n=1,2; m=1 are prepared by polymerization of origin monomer. The process is carried out at 20-25 C in organic solvent in the presence of catalyst, its quantity is (3-6)$$$ moles per 1 mole of origin monomer. Etherate of boron trifluoride is used as catalyst. EFFECT: higher efficiency. 4 tbl

Description

 The invention relates to the production of oligomerization products of 10-propenylphenothiazine, which can be used in the production of stabilized polymer compositions for various purposes.

Phenolic antioxidants are known to be used as thermal stabilizers for polyolefins, for example 2,2'-Thio-bis (4-methyl-6-tert-butylphenol) (Thioalkofen BP) or 4-hydroxy-3,5-di-tert-butylphenylpropionic acid ester and pentraerythritol (Tetraalkofen BPE) (Irganox 1010), as well as oligomeric stabilizers such as the condensation product of bis (2-hydroxy-5-methylphenyl) methane with divinylbenzene (polyphenol 12) [1]
In addition, aromatic and heterocyclic amines are widely used to stabilize polymers.

 The closest to the invention in technical essence and the achieved positive effect is the stabilization of low molecular weight ethylene polymers, where phenothiazine is used as an antioxidant [2] As for the use of phenothiazine and its various alkyl derivatives in the stabilization of other polyolefins or polymers of other classes, there are certain limitations of applicability data stabilizing additives. It is known that phenothiazine and its low molecular weight derivatives sweat to the surface of the stabilized polymer during processing and operation, which limits the use of their dosages in the polymer to an upper compatibility limit of about 1.5 parts by weight. for phenothiazine [3] In addition, phenothiazine and its low molecular weight derivatives do not adequately protect the polymers from a complex of aging factors from the effects of single-strain deformations, ozone, and heat.

 The purpose of the invention is the preparation of new phenothiazine derivatives having a high stabilizing effect for polyolefins, improving the physicochemical characteristics of the polymer compositions stabilized by them during processing and operation.

The goal is achieved in that oligomerization products of 10-propenylphenothiazine are obtained by polymerizing the starting monomer at a temperature of 20-25 ^° C in an organic solvent in the presence of a catalyst of boron trifluoride etherate in an amount of (3-6) • 10 ^-3 mol per 1 mol of the starting monomer.

Example 1. 2.4 g (0.01 M) cis-10-propenylphenothiazine (cis-10-PFT) dissolved in 10 ml of anhydrous organic solvent of ethyl acetate was added to a one-necked flask. 0.1 ml (0.00003 M) was added. a solution of boron trifluoride etherate in ethyl acetate. The synthesis is carried out at 20 - 25 ^o C until the complete conversion of CIS-10-PFT. The input of the reaction is monitored chromatographically (TLC, silofol, hexane: ether 6: 1). The synthesis time is 2 hours. In this case, 25-30 minutes after adding the catalyst to the reaction solution, the appearance of crystals of the substance is observed in the volume of the reaction mass, which then form a precipitate on the walls of the flask. Then, a noticeable increase in sediment volume was observed over 1.5 hours. At the end of the reaction, the catalyst is neutralized with a solution of KOH in methyl alcohol. The precipitate of material that has accumulated during the synthesis process is filtered off, washed successively with 10 ml of ethyl acetate, then with 50 ml of ethanol, and dried. Obtain 1.6 g (66.6%) of white small crystals with So pl. 210-211 ^o C, soluble in chloroform, benzene, poorly soluble in ethyl acetate, acetone, hexane.

IR (UR-20, KBr): 760 cm ^-1 (1,2-substituted benzene rings), 790, 740 cm ^-1 (1,2,3-substituted benzene rings), 1600, 1500, cm ^-1 (C = C aromatic rings). In addition, the absorption spectra of the free NH bond are absent in the IR spectra.

PMR spectrum: (CDCl ₃ ) δ, ppm contains signals characteristic of the ethyl group: 1.02 (3H, t, J = 6 Hz), 1.28 (2H, d, J = 7 Hz), as well as signals in the region of 1.4 1.7 (2H, m,), 2.4-2.85 (1Н, m), 3.94 4.2 (1H, m), 4.8-5.1 (1H, d, J = 11 Hz) and signals of aromatic protons rings 6.5-7.2 (15H, m), M ⁺ = 478.

 These data allow us to identify the obtained cis-10-propenylphenothiazine oligomerization product as 2-methyl-1-ethyl-3- (10-phenothiazinyl) -2,3-dihydro-1H-pyrido [3,2,1-k, l] phenothiazine (POL-1).

Элементный анализ:
Найдено, C 76,70; H 5,69; N 5,43; S 12,99.

Elemental analysis:
Found, C, 76.70; H 5.69; N, 5.43; S 12.99.

 Calculated, C 75.31; H 5.43; N, 5.85; S 13.38.

 In addition to the main reaction product, POL-1, at a given duration of synthesis, oligomeric derivatives of cis-10-PFT (POL-2) are present in the reaction mixture. A likely structural formula is given in Examples 5-6.

Examples 2-4. The oligomerization product cis-10-PFT (POL-1) is obtained analogously to example 1, but the synthesis time varies from 0.67 to 3.2 hours. The precipitation of the precipitated POL-1 is analogous to example 1. Receive from 28.5 to 75.4 % POL-1 with So pl. 210-211 ^o C.

Examples 5-6. The oligomerization products of cis-10-propenylphenothiazine (POL-2) are obtained analogously to Example 1. The resulting precipitate POL-1 is left in the reaction solution. Monitoring the progress of the reaction is carried out by the TCX method. The duration of the synthesis is increased to 18-21 hours. During this time, the formed sediment POL-1 is almost completely dissolved. At the end of the reaction, the catalyst is neutralized with a solution of KOH in methanol. From the reaction mixture, the precipitate POL-1 precipitated after neutralization is filtered. The filtrate is planted in 450 ml of ethanol (methanol) and 20 ml of water. The precipitate formed is filtered off, washed with 100 ml of ethanol, and dried. Get a light gray powder oligomeric derivatives of cis-10-propenylphenothiazine POL-2 with a yield of 30-37.5% T. pl. 140-150 ^o C. M.M. 510-1030 (cryoscopy, naphthalene). POL-2 is highly soluble in most organic solvents except saturated hydrocarbons.

Предложенная структура продуктов олигомеризации (ПОЛ-2) удовлетворительно согласуется с данными элементного анализа:
Найдено, C 76,70; H 5,69; N 5,43; S 12,99.The infrared spectrum (UR-20, KBr) shows the presence of absorption bands of the free amino group (3370 cm ^-1 ), 1,2-substituted (760 cm ^-1 ), 1,2,3-substituted (790, 740 cm ^-1 ) 1,2,4 substituted (880, 820 cm ^-1 ) benzene rings. The structure of the synthesized oligomers can be represented by the following structural formula:

The proposed structure of oligomerization products (POL-2) is in satisfactory agreement with the data of elemental analysis:
Found, C, 76.70; H 5.69; N, 5.43; S 12.99.

 Calculated, C 75.31; H 5.43; N, 5.85; S 13.38.

 Example 7. The oligomerization process of cis-10-PFT is carried out analogously to example 5, but methylene chloride is used as a solvent. The synthesis time was 6 hours. Oligomerization products (POL-2) were obtained in 68.8% yield (Table 1).

 Example 8. The oligomerization process of cis-10-PFT is carried out analogously to example 5, but toluene is used as a solvent. The synthesis time was 6 hours. Oligomerization products (POL-2) were obtained in 90.8% yield (Table 1).

Thus, the proposed method allows to obtain oligomerization products of CIS-10-PFT POL-1 with yields of 28.5-75.4% and POL-2 with yields of 30-91%
POL-1 and POL-2 were used as thermal stabilizers of polyolefins in the following ratio of components, wt.

Polyolefin 99.7 99.9
POL-1 or POL-2 0.1 0.3
Example 9. A composition based on high pressure polyethylene (LDPE) is prepared by mixing 998 g of LDPE with 2 g (0.2 wt.) Of POL-1 on rollers at 160 ^o C. Evaluation of the stabilizing effect is carried out by changing the melt flow rate (MFR) during the exposure of the polymer in air at 200 ^o C for two hours, as well as the time the pH of the electrolyte solution changes as volatile products of polymer degradation accumulate during aging at 180 ^o C in an oxygen stream (τ _pH ) according to TU 301-05- 91. The results are presented in table.2.

 Example 10, 11. Compositions based on LDPE are prepared and tested analogously to example 9, but the stabilizer is added at a concentration of 0.1 wt. and 0.3 wt.

 Examples 12 14. Compositions based on LDPE with additives of 0.1-0.3% POL-2 are prepared and tested analogously to example 9 (table 2).

 Example 15. A composition based on LDPE is prepared and tested analogously to Example 9, but Irganox-1010 (a product of Ciba-Geigy) is used as a heat stabilizer (Table 2).

Examples 16-18. Compositions are prepared on the basis of Sevilen grade 11306-075, which contain 0.1-0.3% POL-1 as a stabilizer. The polymer with the additive was mixed in a high-speed mixer at room temperature for 10 minutes. Then the mixture was extruded on a single screw worm extruder with a ratio of the length of the worm and the diameter of 20: 1 at temperatures of 100-110-120 ^o C in zones. Discs of 1 mm thickness were cast from granules at 130-140 ^° C and a pressure of 80 MPa.

Assessment of the thermostabilizing effect of additives in compositions based on sevilen is carried out according to TU 301-05-91 according to the time the pH of the electrolyte solution changes as volatile products of polymer degradation accumulate during aging at 180 ^o C in an oxygen stream τ _pH , as well as a change in the yield index melt (MFR) during the exposure of the composition in air at 200 ^o C for two hours. MFR was determined according to GOST 11645-73. The composition and results are shown in table.3.

 Examples 19-21. Prepare and test compositions based on Sevilen grade 11306-075, which contain 0.1-0.3% POL-2 as a stabilizer (Table 3).

 Example 22. A composition based on sevilen is prepared and tested analogously to Example 17, but Irganox-1010 is used as thermostabilizer (Table 3).

Examples 23 and 24. Compositions based on polypropylene are prepared by displacement (polypropylene and thermostabilizer) in a high-speed mixer at room temperature for 10 minutes, followed by extrusion on a single screw worm extruder at a temperature of 170-160 ^o C in the zones of the cylinder. The stabilizing effect of the additives is assessed by the time the pH of the electrolyte solution changes as acidic products of polymer degradation accumulate in it in an oxygen stream at 180 ^o C and 160 ^o C τ _pH , as well as according to GOST 26996-86 “Polypropylene and propylene copolymers”, paragraph 5.12 at 150 ^o C (τ _ocher. ) (table 4).

 Example 25. A composition based on PP is prepared and tested analogously to examples 23, 24, but Irganox 1010 is used as a stabilizer.

 From the data given in Tables 2-4, it can be seen that the proposed compositions based on polyolefins containing POL-1 and POL-2 as thermostabilizers according to the stabilizing effect (according to the determination of the induction period of pH changes) are at the level of the well-known industrial stabilizer Irganox 1010 or superior to him. According to the determination of the change in MFI, both products are superior to Irganox 1010, which allows them to be used as stabilizers for polyolefins.

Literature:
1. Chemical additives to polymers. / Ed. I.P. Maslova. M. Chemistry, 1973 p. 70, 75, 118.

 2. Murphy C.M. Sanders C.E. Petroleum Refiner, Vol. 26, P. 479, 1947.

 3. Copyright certificate 1027177, C 08 L 9/00, C 08 K 5/46. Vulcanizable rubber compound based on carbochain rubber. S.S. Nikulin, Yu.F. Shutilin, M.I. Cherkashin, V.M. Misin, A.P. Zvonkova, M.P. Parinova. Claim 03/04/82. Publ. 07/07/83. Bull. N 25.

 4. Skvortsova G.G. Shostakovsky M.F. and Kurov G.N. Zhurn. Org chemistry. 1972, v. 8, p. 382-387.

Claims (1)

Oligomerization products of 10-propenylphenothiazine of the general formula
where n 1, 2;
m 1
as stabilizers for polyolefins.

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