CS231042B1 - Rubber compound - Google Patents

Abstract

This is a composition of a special rubber mixture that allows cleaning of vulcanization molds from settled rubber mixture residues and impurities. High cleaning ability is achieved by using the active chemical substance 1,6 hexanediamine, which is mixed with 8 other additives into the respective elastomer or into a combination of elastomers. The cleaning rubber mixture according to the invention can be used in particular for cleaning vulcanization molds in injection molding machines, but also for cleaning vulcanization molds during classic pressing on hydraulic stacking presses. It is therefore used in the rubber industry in the production of technical rubber.

Description

(54) Rubber compound

It is a composition of a special rubber compound, which allows the vulcanization molds to be cleaned of settled rubber compound residues and impurities. High cleaning performance is achieved by using the active substance 1,6 hexanediamine, which is mixed together with 8 other additives into the respective elastomer or a combination of elastomers. The cleaning rubber compounds according to the invention can be used in particular for cleaning vulcanizing molds in injection molding machines, but also for cleaning vulcanizing molds in conventional pressing on hydraulic deck presses. It is therefore an application in the rubber industry in the production of technical rubber.

The object of the invention is a special rubber compound based on elastomers such as butedienacrylonitrile, butedienstyrene and combinations thereof, which after removal and vulcanization remove the deposited residues of rubber mixtures and impurities from the surface of the vulcanization molds. ‘

In the manufacture of technical rubber, vulcanization molds become contaminated, at least by the deposition of rubber compound residues. Once the contamination reaches the degree that residual contaminants cause defects on the products, contaminants must be removed from the vulcanization molds. This is done mechanically using a metal pile brush, or chemically by elevated temperature caustics, a combination of the above methods, or rubber mixtures.

The method in which a cleaning rubber composition is used is the most economical and laborious process. In this process, however, the rubber composition used is highly dependent on the cleaning performance of the rubber composition, and the cleaning effect can then be influenced positively or negatively by the composition of the rubber composition and the type of active substance used to remove impurities.

Until now, the polyglycolamine active substance in an amount of about 30 parts by weight per 100 parts by weight of rubber is used in the mold cleaning compositions of ethylene-propylene rubber molds. For cleaning purposes, a cleaning composition based on ethylene-propylene rubber with 30 parts by weight of 2-amino-2-methyl-1-propanol per 100 parts by weight of rubber is recommended. However, these cleaning compositions cannot be applied to all elaetomers, and furthermore, their cleaning effects are not at such a level that only the above method could be used to clean the molds.

The above drawbacks are eliminated by using the rubber cleaning composition of the present invention which is prepared on butadiene acrylonitrile, hutedlenathylene rubber, or a combination thereof, and 1,6-hexanediamine or hexamethylenediamine CgHggNg in an amount of from 15 to 50 parts by weight per 100 parts by weight is used. rubber parts. This amia aa is applied to the vulcanization mold at a vulcanization temperature in the range of from 150 to 200 ° C and after its vulcanization and removal from the mold, the impurities deposited on the surface of the vulcanization mold are completely removed. The use of the composition according to the invention is not limited to the type of elastomer which contains the impurities.

He did

From the following elestomers, a mixture of the following composition was mixed:

Butadiene acrylonitrile rubber

Butadiene styrene rubber

Zinc oxide

Atearic acid

Silica

Calcium carbonate - ground

Titanium dioxide Sulfur ground

Dicumyl peroxide 1,6-hexanediemine wt. parts 40 h. parts 2 wt. parts 40 wt. parts 10 wt. parts 10 wt. »parts 0.5 wt. parts 3.5 wt. parts 20 wt. parts

Of the following elaetomers, a mixture of the following composition was mixed:

Butedlenacrylonitrile rubber 70 wt. parts Butadiene styrene rubber 30 ha. parts Zinc oxide 5 wt. parts Stearic acid 1.5 wt. parts Silica 40 wt. parts Calcium carbonate - ground 10 wt. parts Titanium dioxide , 0 wt. parts Sulfur ground 0.5 wt. parts Dikumylperoxid 3 wt. parts 1,6-hexanediamine 20 wt. parts

In general, a large number of longer variations of these recipes can be used, so the examples are not to be construed as limiting the choice of their composition.

Furthermore, two comparative mixtures based on ethylene propylene rubber of the following composition were mixed:

Ethylene-propylene rubber 100 wt. d. 100 wt. d. Zinc oxide 5 wt. d. 5 wt. d. Stearic acid 1 wt. d. 1 wt. d. Silica 20 wt. d. 20 wt. d. Titanium dioxide 10 wt. d. 10 wt. d. Sulfur ground 0.3 wt. d. 0.3 wt. d. Dikumylperoxid 9 wt. d. 9 wt. d.

Polyglycolamine 30 wt. d.

2-amino-2-methyl-1-propanol - 30 wt. d.

Plates of 150 x 150 x 2 mm were prepared from the blends, placed in a four-print laboratory mold contaminated by vulcanization of blends with different elastomers, and cured at 170 ° C. By using a four-printing mold, a presumption of the same level of contamination was created in the inhalation of vulcanization chambers. After removal of the vulcanized plates of the cleaning compositions, the coating of the plates was visually evaluated for residual impurities corresponding to the degree of cleaning of the respective vulcanization chamber. In the composition of the invention shown in Examples 1 and 2, 90-95% of the impurity coverage of the plate was achieved. For the blend with 2-amino-2-methyl-1-propanol, 75-80 $ of the plate coverage was achieved, and for the blend and polyglycolamine around, 60 $ of the plate coverage was obtained.

The invention can be used in the field of the production of technical rubber for cleaning, in particular, vulcanizing molds on injection molding machines, and also for cleaning molds in conventional stamping on hydraulic deck presses.

Claims (1)

OBJECT OF THE INVENTION High purifying rubber composition for removing sediment on vulcanizing molds based on butadiene acrylonitrile, butadiene styrene rubber or a combination thereof, containing conventional additives, fillers and vulcanizing agents, characterized in that it contains 15 to 50 parts by weight hexanediamine per 100 parts by weight of rubber.