RU2503701C1 - Method of gluing rubber - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: vulcanised rubber is glued to each other by applying an adhesive based on isoprene rubber solution in nefras onto the surfaces to be glued. The surfaces are then dried and brought into contact. The isoprene rubber in the adhesive is SKI-3 rubber which is pre-ozonised for 0.5-1.0 hour at room temperature. The adhesive is applied in two steps while drying the adhesive film at room temperature for 10 minutes after applying the first layer and for 1-2 minutes after applying the second layer.

EFFECT: invention provides high strength of the adhesive joint when gluing vulcanised rubber to each other and simplifies the gluing technique.

2 ex, 1 tbl

Description

The invention relates to a method for attaching vulcanized rubbers to each other and can be used in the rubber industry.

There is a method of attaching rubbers based on various rubbers to each other by applying glue based on natural rubber onto the glued surfaces and then contacting the surfaces, and before applying to the surface, a modifier selected from the range of N-nitrosodiphenylamine, orthophenylenediamine or paraoxydiphenylamine is additionally introduced into the adhesive (Pat. RF №2408640, C09J 107/00; publ. 10.01.2011).

However, in this method, natural rubber is contained as the basis of the adhesive composition.

A known method of bonding vulcanized rubbers to each other, which consists in a one-time application of the prepared glue on the prepared rubber surface, drying the adhesive film at room temperature (20 ° C) for 1-2 minutes and tightly pressing the glued surfaces, and chlorinated is used as the adhesive composition natural rubber brand CR-20 in toluene, epoxy diane resin ED-20 in an amount of 5-15 wt.h. and additionally as an FBM modifier in an amount of 3-10 parts by weight (Pat.RF No. 2435818, C09J 115/02; publ. 10.12.2011).

However, in this method, natural rubber is contained as the basis of the adhesive composition, and the method itself requires the preliminary preparation of a modifier and the use of a more complex formulation.

The closest is the method of producing a self-adhesive material, which consists in applying an adhesive composition to an aluminum substrate, including 3,4-isoprene rubber with a vinyl content of 83-88%, as well as a plasticizer - paraffin oil or low molecular weight polybutadiene, terphenolic resin as an adhesive additive and the solvent is nefras (Pat. RF №2322470, CL C09J 109/00; publ. 20.04.2008).

However, this method is intended for bonding aluminum foil and aluminum alloys.

Objective: to develop a method of attaching rubbers to each other, providing increased bonding strength of vulcanized rubbers to each other.

The technical result is to provide increased strength of the adhesive joint when attaching vulcanized rubbers to each other, as well as simplifying the bonding method.

The technical result achieved is achieved in that the method of fixing vulcanized rubbers to each other by applying glue based on a solution of isoprene rubber in nefras to the surfaces to be bonded, followed by drying and contacting the surfaces, is characterized in that it contains SKI-3 rubber, previously ozonized for 0.5-1.0 hours at room temperature, and the application of glue is carried out in two stages with drying of the adhesive film at room temperature for 10 minutes after nan Oran first layer and within 1-2 minutes after the application of the second layer.

Synthetic isoprene rubber brand SKI-3 (TU 2294-037-48158319-2003) is the main film-forming in adhesive adhesives.

Nefras is an organic solvent (TU 38.401-67-108-92).

When ozonation of the specified rubber significantly increases the adhesive properties of the adhesive composition. This is due to an increase in the content of functional groups in the adhesive composition that exhibit high adhesive activity. This explains the increase in strength when bonding vulcanized rubber to each other.

The stated time limits for ozonation are due to the fact that, with a decrease in the time of ozonation, preliminary degradation of rubber macromolecules occurs, as a result of which the adhesion strength during bonding of rubbers to each other decreases, the increase in ozonation time does not lead to an increase in adhesive strength.

The method of attaching rubbers to each other is as follows.

Before applying glue based on a solution of isoprene rubber and nefras on glued surfaces, this rubber was preliminarily ozonized at room temperature 23 ° C in an ozone chamber at an ozone concentration of 5 · 10 ^-5 . This method was used for fixing vulcanized rubbers based on isoprene rubber. (SKI-3), ethylene propylene rubber (SKEPT-40), nitrile butadiene rubber (SKN-18M) and chloroprene rubber (Neoprene AC) to each other. Two-time application of the prepared adhesive on the prepared surface, drying of the adhesive film at a temperature of 23 ° C for 10 minutes after applying the first layer and 1-2 minutes after applying the second, after which the glued surfaces were pressed tightly and held under a load of 2 kg for 24 hours .

Shear adhesion was determined using an MPC-250 tensile testing machine (RTM 1.2.126-88). Various ozonation times of isoprene rubber were investigated (Table 1).

The method is illustrated by the following example.

Example 1. Before applying glue based on a 5.% solution of SKI-3 brand isoprene rubber in nefras on glued surfaces, this rubber was pre-ozonated for 0.5 hours at room temperature 23 ° C in an ozone chamber at an ozone concentration of 5 · 10 ^{- 5} .

Example 2. Obtain adhesive compounds as described in example 1, but the rubber is pre-ozonized for 1 hour.

This method was used for fixing vulcanized rubbers based on SKI-3, SKEPT-40, SKN-18M and Neoprene AC to each other. Two-time application of the prepared adhesive on the prepared surface, drying of the adhesive film at room temperature 23 ° C for 10 minutes after applying the first layer and 1-2 minutes after applying the second, after which the glued surfaces were pressed tightly and held under a load of 2 kg for 24 hours. After that, shear strength was determined.

As can be seen from table 1, the proposed method of attaching vulcanized rubbers to each other provides high strength properties of adhesive joints. Thus, the shear strength of an adhesive joint when gluing vulcanized rubber based on SKEPT-40 with adhesive based on a 5% solution of SKI-3 isoprene rubber according to the control example is 0.31, and using SKI-3-0 ozonized for 0.5 hours , 54 MPa (composition 1).

Table 1 Substrate Type Metric for composition Test case one 2 Ozonation time, hour 0 0.5 1,0 Shear Strength, MPa SKI-3 0.36 - 0.39 SKEPT-40 0.31 0.54 0.53 SKN-18 0.26 0.27 - Neoprene speaker 0.27 0.45 0.28

We found that the reason for the increase in the adhesive characteristics of the adhesive composition is the reactivity of the macroradicals formed during ozonation, which leads to hardening of the adhesive film.

The technical and economic effect obtained from the application of the fastening method lies in the fact that its application allows to increase the strength of the adhesive joint when bonding vulcanized rubbers to each other, as well as to simplify the bonding technology.

Claims (1)

A method of attaching vulcanized rubbers to each other by applying glue based on a solution of isoprene rubber in nefras to the glued surfaces, followed by drying and contacting the surfaces, characterized in that as isoprene rubber it contains SKI-3 rubber, previously ozonized for 0.5 -1.0 hours at room temperature, and the application of glue is carried out in two stages with drying of the adhesive film at room temperature for 10 minutes after applying the first layer and for 1-2 minutes after applying the second layer.