SU734230A1 - Unsaturated low-molecular weight rubber-based rubber mixture - Google Patents

Description

The invention relates to the rubber industry, in particular to the development of a rubber mixture based on unsaturated rubber. A well-known rubber mixture based on HeHacbnueHHotxa low molecular weight rubber, comprising a vulcanizing agent-sulfur and the product of the interaction of equimolecular amounts of triethylamine, propylene oxide and ethyl alcohol. Rubber from this mixture have a low elongation. The purpose of the invention is to increase the relative elongation of rubber from a rubber mixture based on unsaturated rubber. The goal is achieved with the fact that a rubber mixture based on low molecular weight unsaturated rubber, including a vulcanizing agent and a vulcanization accelerator, as a vulcanizing agent contains the product of propyl oxide and sulfur interaction with a sulfur content of 3050% by weight, obtained in the presence of a tertiary amine (TA ) (for example, triethylamine - TEA, dimethylbenzyl on - DMBA) and water or alcohol, for example, ethyl with a molar ratio of propylene oxide, sulfur, tertiary amine and water or alcohol, respectively 1: 1.7-3: 0.1-1 : 0.1-1, and The components of the mixture are taken up in the following amount, parts by weight: Unsaturated low molecular weight rubber 100 Specified product 4-30 Vulcanization accelerator O, 5-5 Production conditions and characteristics of oligomeric polysulfides (OPS) obtained from propylene oxide (S) and sulfur (S) in the presence of TA and the proton of the donor (PD) are presented in tabl.1. These products of the interaction of propylene oxide with sulfur are completely codified with rubber and have a special property (1 1) to create a more flexible (labile) mesh, playing the role of a cross-linking plasticizer. An unsaturated, low-molecular-weight rubber, for example, palibutadien, polyisoprene, and their copolymer, polyisoprene, and their copolymer rubber are used as the basis for the composition. etc. As a vulcanizadia accelerator, it is used by any known accelerator or group of accelerators belonging to classes such as thiazoles.

sulfenamides, dithiocarbamates, thiurams,. Xanthates, guanidines, aldehydamines, etc.

Additives are added to the composition, for example, zinc oxide, stearic acid, etc.

The invention is illustrated by the following examples. The results of the physico-mechanical properties of the tests are given in table 2.

Example 1 (control). 100 g of cis-1,4-polybutadiene (M 35000), 0.5 g of diphecylguanidine (DFG), 1.2 g of methyl cymate (Y), 1.0 g of zinc oxide, 4.0 g of sulfur are swept on rollers during 15 minutes. The mixture is boosted for 40 min at a residual pressure of 10 mm Hg. to remove air and vulcanized in closed forms in a thermostat at.

Example 2 (control). Volcanic acid is prepared according to the method of Example 1, but sulfuric recipe is proportional to but halved, i.e. per 100 g of polymer take 2 g of sulfur, 0.6 g of MC, 0.5 g of zinc oxide, 0.25 g of DFG.

Example 3 (control). Vulcanizates are prepared according to the method of Example 1, but an additional BO of g transformer oil is added to the mixture as a plasticizer.

Example 4 control). Vulcanizates were prepared according to the method of Example 1, but 4.4 g DAS of the product of the interaction between equimolar amounts of gfopilen oxide, triethylamine and ethyl alcohol were additionally added to the mixture simultaneously with sulfur.

Examples 5-10. Vulcanizates are prepared as in Example 1, but instead of sulfur, one of the samples is supplied with the product of the interaction of propylene oxide with sulfur (OPS) in an amount to ensure that the same 4 g of sulfur is present in the system.

Example 11. A mixture is prepared as in Examples 5-10, but vulcanized for 60 minutes in a press at 105c.

Example 12. Vulcanizates are prepared as in Example 11, but DFG is absent in the formulation.

Example 13. Vulcanizates are prepared as in Example 12, but an OPS is added in an amount to provide 2 parts by weight in the system. sulfur.

Example 14. Vulcanizates are prepared as in Example 12, but an OPS is added in an amount that provides 12 parts by weight in the system. sulfur. five

As follows from the comparison of the examples given, Vulcanizates obtained in the presence of the proposed product, the interaction of propylene oxide 0 and sulfur with a sulfur content of 30-50 wt.% (Examples 5-10) have such a high relative elongation that was not achieved in any from known compositions (reference examples 5 1,2,3,4) while maintaining tensile strength 4-5 kgf / cm.

The use of the proposed product of the interaction of propylene oxide and sulfur instead of powdered sulfur provides, thanks to good compatibility with rubber and plasticizing ability, a better distribution of vulcanizing cHcTeivM in rubber, and allows for reducing the preparation of mixtures, the number and number of ingredients to improve the recipe. properties of mixtures, as well as significantly increase the relative elongation of rubber from these mixtures.

Table 1

470,659,92270

34,952.72-10,45,44, 00,899,549 .051,011,5230 42,40,910,15265

41.60,5710,7260 42,81,3310,05229

Table 2

Claims (1)

Claim Rubber mixture based on unsaturated low molecular weight rubber, including a vulcanizing agent and a vulcanization accelerator, characterized in that, in order to increase the relative elongation of rubber from this mixture, the latter as a vulcanizing agent contains the product of the interaction of propylene oxide and sulfur with a sulfur content of 30-50 weight. %. obtained in the presence of a tertiary amine and water or alcohol at a molar ratio of propylene oxide, sulfur, tertiary 45 50 amine and water or alcohol, respectively, 1: 1.7 - 3: 0.1 - 1: 0.1-1, and the components of the mixture are taken in the following quantity, parts by weight: Unsaturated low molecular weight rubber The specified product Vulcanization accelerator 100 4-30 0.555