CS201142B1 - Rubber mixture for rubber objects with metal construction - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber composition for rubber articles having a metal skeleton.

The prior art methods of bonding metal to rubber achieve good strength between the chemically treated metal surface and the rubber in rubber-metal products, especially steel cord tires, steel cord conveyor belts, rubber-metal technical rubber and other dynamically lubricated products. Coating of brass, zinc or copper surfaces is commonly used. The surface treated in combination with a rubber composition based on a high content of natural rubber or polyisoprene rubber with a high cisreoregularity of 1.4 gives a high bond strength after vulcanization with good resistance to mechanical fatigue and thermal aging.

Another method of increasing the durability of rubber products with a textile or metal skeleton is to use the active substances in a rubber compound. This is mentioned, for example, in British Patent No. 1,317,166, which deals with increasing the durability of rubber products containing a textile or metal skeleton, or in U.S. Pat. No. 132,381, which addresses the increase in durability of rubber-textile products. In both cases, the active ingredients are used in a rubber composition, in particular hexansthylenesorzoin (so-called resotropin), which is a necessary component of the composition. These active substances form resins during vulcanization, which provide increased bond strength between the textile or metal surface and the rubber.

- 2 201 142 containing reactive groups, thereby increasing the service life of the products. The synergistic effect of active silica fillers is usually used to further increase the service life. The disadvantages of these methods are:

In the first case, it is necessary to import ever-increasing amounts of natural rubber, mainly in the context of β development of steel cord tires, which is prospectively unbearable.

In the latter case, the handling of the mixture is complicated and all of the existing truly effective systems utilize resorcinol, which is a scarce raw material worldwide, as one component.

These disadvantages are overcome by the use of the rubber composition according to the invention.

The present invention relates to a rubber composition for rubber articles having a metal backbone containing rubbers having polymerized RR ₁ monomers in the chain, wherein R is an aldehyde group and R 1 is a diene, preferably butadiene.

The rubber composition of the invention comprises reactive groups incorporated into the chain of one of the rubbers, such as a rubber with reactive aldehyde groups, prepared according to Art. No. 132,708. By using these special rubbers having aldehyde, epoxy or vinylpyridine groups or a combination of these groups in the chain, high bond strengths between the metal surface and the rubber, resistance to the dynamic stresses of these bonds, of which natural rubber is partly or wholly replaced by synthetic rubbers.

The application of the invention allows the use of synthetic rubbers, or domestic production, as a partial or complete substitute for imported natural rubber.

In the following, the invention is illustrated by way of example.

Example

A mixture of A was mixed from butadiene styrene rubber containing 6% aldehyde groups. The same mixture was prepared from butadiene styrene rubber and 30% styrene - mixture B. A mixture of the same composition was prepared in which the rubbers were replaced with 100% natural rubber - mixture C. The obtained mixtures were rubberized with a steel brass confcruk cord 7x3x0.175 + 1x0.15. Buffer belts of radial truck tires combined were made from this semi-finished product. The tires were tested for dynamic carcass fatigue at the drum test stand. The service life of tires made from mixture A and C was the same within the accuracy limits of the method, for the mixture Β 5% lower.

The composition of composition A was supplemented with active substances forming phenol-formaldehyde resin and active silica upon vulcanization. This mixture, hereinafter referred to as D in the table, was used in the same way to produce radial tires. The dynamic life of the skeleton of these combs, determined in the drum test room, was again equivalent to that of sheaths with a coating composition based on 100% natural rubber (Part C) and hence a blend of butadiene styrene rubber containing 6% aldehyde groups (mixture A).

The composition of mixtures A, B, C and D is shown in the following table:

201 142

mixture A (dsk) mixture B (dsk) mixture 0 (dsk) mixture D (dsk) Natural rubber type RSS-1 20.0 20.0 100.0 20.0 Polyieoprene cis rubber 1.4 (Europren IP 60) 60.0 60.0 60.0 Styrene-butadiene rubber (Kralex 010,400) 20.0 Aldehyde SBR 20.0 - - 20.0 Stearin 1.5 1.5 1.5 1.5 Plasticizer (Triumph) 2.5 2.5 2.5 2.5 ZnO 10.0 10.0 10.0 10.0 Carbon black type HAF Nigros K 40.0 40.0 40.0 35.0 Carbon black type MPC (DG-100) 20.0 20.0 20.0 15.0 SiOg (Siloxic) - - 15.0 Phenyl-naphthylamine (PBN) 1.0 1.0 1.0 1.0 N-isopropyl-N-phenyl- p-phenylenediamine (Santoflex IP) 1.5 1.5 1.5 1.5 2-morpholinobenzothiazole (Santocure MOOR) 0.8 0.8 0.8 0.8 Polymer sulfur, 80% (Structure SU 108) 4.6 4.6 4.6 4.6 Resotropin (condensation product re- sorcine) - - 2.5

Claims (1)

Rubber composition for rubber products with a metal skeleton, characterized by rubbers having polymerized monomers of the R-R? Type in the chain, wherein R is poultry and R? Denotes dlen, preferably butadiene.