RU2503700C1 - Adhesive composition - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: adhesive composition contains isoprene rubber and nefras solvent. The isoprene rubber in the composition is SKI-3 rubber which is pre-ozonised for 0.5-1.0 hour at room temperature.

EFFECT: invention increases strength of gluing vulcanised rubber to each other.

2 ex, 2 tbl

Description

The invention relates to adhesive compositions based on isoprene rubbers and can be used in the rubber industry for bonding vulcanized rubbers based on various rubbers to each other.

Known adhesive composition for electrical insulation tapes, including SKI-3 isoprene synthetic rubber in combination with natural rubber compound and rubber regenerate, as well as M-phenylnaphthylamine-2, natural chalk, mineral oil and oxidized atactic polypropylene (USSR Author's Certificate No. 1237693, class. C09J 107/00; publ. 15.07.94).

However, this adhesive composition has a complex formulation and is intended for the manufacture of adhesive tapes.

Known adhesive composition based on nitrile butadiene rubber, including chlorinated isoprene rubber, phenol-formaldehyde resin, zinc and magnesium oxides, organic solvent and filler (Pat. No. 2418026 Russia, CL 0909 109/02; publ. 10.05.2011).

However, this adhesive composition has a complex formulation and contains nitrile butadiene rubber as a base.

Known adhesive for adhesive tapes on a foam substrate containing isoprene and chloroprene rubbers, an adhesive additive and a solvent, characterized in that in order to increase water resistance and adhesive strength, it further comprises hexamethylenetetramine, hydrochloric acid hydrazine, zinc oxide, carbon black, altax and plasticizer (USSR Author's Certificate No. 1165701, class C09J 7/02; publ. 07.07.1985).

However, this glue has a complex composition and is intended for the manufacture of adhesive tapes.

Known adhesive composition for bonding vulcanized rubbers based on various rubbers with each other and when they are attached to a metal surface, including natural rubber, pine rosin, organic solvent - nefras, as well as epichlorohydrin and aniline as a modifier (Pat.2394866 Russia, C09J 107 / 00; published on July 20, 2010).

However, this adhesive composition has a complex formulation and contains natural rubber as the basis.

Closest to the invention in technical essence is an adhesive composition comprising 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 a solvent - nefras (Pat. No. 2322470 Russia, class C09J 109/00; publ. 04/20/2008).

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

Objective: to develop the composition of the adhesive composition based on ozonated synthetic isoprene rubber, which provides increased bonding strength of vulcanized rubber to each other at room temperature, simplifying the formulation.

The technical result is to increase the strength when bonding vulcanized rubber to each other.

The technical result is achieved by the fact that the adhesive composition comprising isoprene rubber and solvent nefras, and as isoprene rubber it contains rubber brand SKI-3, pre-ozonized for 0.5-1.0 hours at room temperature, in the following ratio of components wt.h .: specified isoprene rubber - 5.0; nefras - 95.0.

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 adhesive composition is prepared as follows. Initially, isoprene rubber is ozonized at room temperature 23 ° C for 0.5-1 hours in a special ozone chamber at an ozone concentration of 5 · 10 ^-5 . Then prepare a solution of ozonized isoprene rubber in nephras. The ozonized rubber and solvent are loaded into an adhesive mixer and mixed for 4 hours until a homogeneous composition is obtained.

An example of the preparation of the adhesive composition.

Example 1. In a glue mixer, isoprene rubber SKI-3 brand, solvent Nefras, pre-ozonized for 0.5 hours at room temperature 23 ° C, is loaded and the contents are mixed for 4 hours until a homogeneous mass is obtained.

Example 2 is similar to example 1, but the rubber is pre-ozonized for 1 hour.

Get adhesive compositions 1-2, the compositions of which are shown in table 1. The glue is a gray liquid. The glue is technological, it is well applied to the surface of rubber. Various ozonation times of isoprene rubber were investigated (Table 1).

The claimed time interval of ozonation of 0.5-1.0 hours is due to the fact that with an increase or decrease in the concentration of ozone, the adhesive strength during bonding decreases.

Comparative tests of the strength properties of adhesive compositions for all variants of the claimed composition and a control example for bonding vulcanized rubber based on isoprene rubber (SKI-3), ethylene propylene rubber (SKEPT-40), nitrile butadiene (SKN-18) and chloroprene rubber (Neoprene AC ) are given in table 2. For comparative tests, 2 variants of the compositions were prepared (according to the method described in examples 1 and 2) and the composition according to the control example presented in table 1. The proposed compositions were tested for the adhesive shear strength achieved when kept under a load of 2 kg at room temperature temperature for 24 hours. The data are presented in table 2.

Shear adhesion was determined using an MPC-250 tensile testing machine (RTM 1.2.126-88). The technology for bonding samples is as follows. Two-time application of the prepared adhesive on the prepared surface, drying of the adhesive film at room temperature for 10 minutes after applying the first layer and 1-2 minutes after applying the second, after which the glued surfaces were pressed tightly.

As can be seen from table 2, the proposed adhesive compositions provide an increase in the strength properties of adhesive joints compared with the control example. So, the shear strength of an adhesive joint when bonding vulcanized rubber based on SKEPT-40 with an adhesive composition in the control example is 0.31, and with the use of SKI-3 ozonized for 0.5 hours, it is 0.54 MPa (composition 1).

Thus, as can be seen from Table 2, when ozonized SKI-3 is used as the base of the adhesive composition, the strength when bonding products from vulcanized rubber based on various rubbers increases, which is due to the participation of reactive groups formed during ozonation in increasing the adhesive properties of the adhesive.

We found that the reason for the increase in the adhesive characteristics of the adhesive composition is the reactivity of macroradicals,

Table 1 The content of components, parts by weight Component Test case one 2 Ozonation time, hour 0 0.5 1,0 SKI-3 isoprene rubber 5,0 5,0 5,0 Nefras 95.0 95.0 95.0

table 2 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

The technical and economic effect obtained from the use of the adhesive composition is that its use allows to increase the strength of the fastening of vulcanized rubber products based on various rubbers formed during ozonation, which leads to hardening of the adhesive film.

Claims (1)

An adhesive composition comprising isoprene rubber and solvent Nefras, characterized in that as isoprene rubber it contains SKI-3 rubber, pre-ozonized for 0.5-1.0 hours at room temperature, in the following ratio, wt.h .:
the specified isoprene rubber is 5.0;
nefras - 95.0.