RU2434031C2 - Adhesive composition - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: adhesive composition contains the following (pts.wt): polychloroprene rubber nairit DP 90.0, butylphenol formaldehyde resin 101K 90.0, water 3.0, zinc oxide 5.0, magnesium oxide 11.0, organic solvent 800.0, which is a mixture of ethyl acetate and nefras, a modifier obtained at room temperature from methylphosphite borate and silica filler Rosil R-175 in ratio of 7-3:1.

EFFECT: invention increases strength when gluing together vulcanised rubber based on different types of rubber.

2 tbl, 10 ex

Description

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

Known adhesive composition comprising chloroprene rubber, thiuram, zinc oxide, as a resin, the product of the joint condensation of phenol of acetaldehyde and acetanaphthene and a solvent (USSR Author's Certificate No. 1579920, class C09J 111/00; Publ. 23.07.90). As a solvent, a mixture of ethyl acetate and gasoline is used.

However, this adhesive composition does not provide a sufficiently high strength when bonding products from vulcanized rubber.

Known adhesive composition comprising polychloroprene rubber, epoxy resin, low molecular weight butadiene nitrile rubber, tertiary amine, solvent (USSR Author's Certificate No. 685673, class C08L 11/00; Publ. 15.09.79).

However, this adhesive composition has low strength when bonding rubber products based on various rubbers.

Known adhesive composition comprising polychloroprene rubber, butylphenol formaldehyde resin, a copolymer of styrene and piperylene, rosin esterified with glycerol; pine rosin, diphenylguanidine, 2,2-dibenzothiazole disulfide, zinc oxide, magnesium oxide, organic solvent (Pat. 2028358 Russia, MKI ⁶ C09J 111/00; Publish. 09.02.95).

However, the specified adhesive composition, although it has a similar composition, is intended for bonding products from ferrites.

Closest to the invention in technical essence is adhesive 88CA (TU 381051760-89), which includes (parts by weight): polychloroprene rubber Nairit DP - 90.0, butylphenol formaldehyde resin 101K - 90.0, zinc oxide - 5, 0, magnesium oxide - 11.0, water - 3.0, organic solvent - 800.0. A mixture of nefras and ethyl acetate in a percentage ratio of 50:50 is used as an organic solvent.

However, the specified adhesive composition (although it is widely used because of its low cost) does not provide a sufficiently high strength when bonding vulcanized rubber (the achieved shear strength when bonding vulcanized rubber based on polyisoprene rubber (SKI-3) does not exceed 1.02 MPa )

Objective: the development of the composition of the adhesive composition having increased strength when bonding vulcanized rubbers to each other.

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

The technical result is achieved in that the adhesive composition comprising polychloroprene rubber Nairit DP, butylphenol-formaldehyde resin 101K, water, zinc oxide, magnesium oxide, an organic solvent, which is a mixture of ethyl acetate and nefras, and it additionally contains a modifier previously obtained by interaction with room temperature borate methylphosphite and silica filler Rosil grade R-175 with a ratio of 7-3: 1, in the following ratio of components, parts by weight: polychlorine Nairit DP oprenic rubber - 90.0, butylphenol formaldehyde resin 101K - 90.0, water - 3.0, zinc oxide - 5.0, magnesium oxide - 11.0, the indicated organic solvent - 800.0, methyl phosphite borate - 8, 75-2.25, silica filler Rosil grade R-175 - 2.5-0.37.

Polychloroprene rubber Nairit DP (TU-6-01-1319-85) is the main film-forming in adhesive adhesives.

Butylphenol formaldehyde resin 101K (TU-60004691277193-97).

Vulcanizing group: zinc oxide (zinc white GOST 202-84), magnesium oxide (burnt magnesia GOST 844-79) were previously used in adhesive compositions (Kardashov D.A., Petrova A.V. Polymer adhesives. M: Chemistry, 1983 )

Organic solvent: a mixture of ethyl acetate (GOST 8981-78) and nefras (GOST 3840167109-92).

Methylphosphite borate is a viscous unpainted liquid, readily soluble in water, dimethylformamide, acetone, alcohols (US Pat. No. 2190697). Widely known as a combustion inhibitor.

Silica filler Rosil grade R-175 (Rosil-175) (TU 2168-038-00204872-2001), is a fine precipitated silicon dioxide. It is used for the production of tires, rubber products, artificial leather, in the paint and varnish, oil industry.

The modifier is obtained by direct interaction of methylphosphite borate and Rosil silica filler grade P-175 at a ratio of 7-3: 1, at room temperature for 1 hour. The modifier is a viscous mass of white.

When using the specified modifier, the adhesive properties of the adhesive composition are significantly increased. This is due to an increase in the content of functional groups in the adhesive composition. As a result of the interaction of this modifier with a polychloroprene rubber macromolecule, an increase in the concentration of polar groups and the formation of additional chemical bonds, which increases the mobility of the polychloroprene macromolecule and a deeper diffusion of its sections deeper into the surface of the vulcanizate. This explains the increase in strength when bonding vulcanized rubbers to each other.

The adhesive composition is prepared as follows. First, the rubber mixture 31С-1-ДП is prepared - a mixture of Nairite DP, magnesium oxide, zinc oxide (ЕТР 8857-91) in a rubber mixer for 10 minutes, while the temperature of the mixer gradually rises (as the components of the mixture are introduced) from 50 ° C to 85 ° C. After unloading the mixture at a temperature of 105 ° C, it is paged for 5 minutes. Then the heated rubber mixture with a part of the solvent (about 0.1 part of the total amount of solvent) is loaded into the glue mixer. The remaining amount of solvent, together with other ingredients of the adhesive composition, with butylphenol formaldehyde resin, water, a modifier, are loaded in portions into the adhesive mixer as the rubber mixture swells. The total adhesive mixing time is 4.5-5 hours, while the introduction of the modifier can be carried out after preparation of the adhesive composition based on the remaining components.

An example of the preparation of the adhesive composition. Into an adhesive mixer containing 88CA nairite adhesive (TU 381051760-89) prepared in a known manner, including polychloroprene rubber Nairit DP, 101 K butylphenol formaldehyde resin, zinc oxide, magnesium oxide, water and the indicated organic solvent, the calculated amount of the specified modifier is introduced and the mixture is introduced and the mixer 5-10 minutes until a homogeneous mass.

Get the adhesive composition 1-9, the compositions of which are shown in table 1. The glue is a beige liquid. The glue is technological, it is well applied to the surface of rubber. Various contents of the specified modifier were investigated (Table 2).

The stated ratio of the modifier Borate methylphosphite: Rosil-175 7-3: 1 due to the fact that with an increase or decrease in these dosages, the adhesive strength during bonding decreases.

Comparative tests of the strength properties of adhesive compositions for all variants of the claimed composition and prototype when bonding vulcanized rubber based on polyisoprene rubber (SKI-3) and ethylene-propylene rubber (SKEPT-40) and chloroprene rubber (Neoprene) are given in table 2. For comparative tests, 9 variants of the compositions were prepared (according to the method described in the example) and the composition of the prototype presented in table 1. The proposed compositions were tested for adhesive shear strength, achieved when kept under a load of 2 kg, at room temperature (20 ° C) within 24 hours.

The data are presented in table 2, which shows that the proposed composition is superior to the control example in terms of shear strength.

Shear adhesion was determined using an MPC-250 tensile testing machine (RTM 1.2.126-88). The technology for bonding samples is as follows. One-time application of the prepared glue on the prepared surface, drying of the adhesive film at room temperature (20 ° C) for 1-2 minutes, after which the adhesive surfaces were tightly pressed.

As can be seen from table 2, the proposed adhesive compositions provide an increase in the strength properties of adhesive joints in comparison with the prototype. So the shear strength of the adhesive joint when bonding vulcanized rubber based on SKI-3 according to the prototype is 1.02 MPa, and using the proposed modifier 1.65 MPa.

Thus, when used in the proposed adhesive composition, the specified strength increases when bonding vulcanized rubber products based on various rubbers, which is due to the participation of this modifier in improving the adhesive properties of the adhesive.

We found that the reason for the increase in the adhesive characteristics of the adhesive composition is not only an increase in the concentration of polar groups when a modifier is introduced into the composition, but also the formation of additional chemical bonds during the interaction of this modifier with mobile allylic chlorine atoms in polychloroprene rubber macromolecules, which leads to an increase in the density of the spatial network and, apparently, to hardening the adhesive film.

Table 1 Component The content of components in the composition, parts by weight one 2 3 four 5 6 7 8 9 Test Case Adhesive 88CA Polychloroprene rubber Nairit DP 90.0 90.0 90.0 90.0 90.0 90.0 90.0 90.0 90.0 90.0 Butylphenol formaldehyde resin 101K 90.0 90.0 90.0 90.0 90.0 90.0 90.0 90.0 90.0 90.0 Water 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 Zinc oxide 5,0 5,0 5,0 5,0 5,0 5,0 5,0 5,0 5,0 5,0 Magnesium oxide 11.0 11.0 11.0 11.0 11.0 11.0 11.0 11.0 11.0 11.0 Organic solvent (a mixture of ethyl acetate and nefras in a percentage of 50:50) 800,0 800,0 800,0 800,0 800,0 800,0 800,0 800,0 800,0 800,0 Methyl Phosphite Borate 2.63 4.38 8.75 2,50 4.17 8.33 2.25 3.75 7.50 - Rosil brand R-175 0.37 0.62 1.25 0.50 0.83 1,67 0.75 1.25 2,50 -

table 2 Substrate Type Shear Strength, MPa Metric for composition Test Example Adhesive 88CA one 2 3 four 5 6 7 8 9 SKI-3 1.31 1.15 1,08 1.23 1.65 1.43 1.15 1.44 1.10 1,02 SKEPT-40 0.97 0.98 0.91 0.98 1,04 1.20 1.00 1.20 0.97 0.70 Neoprene 1.23 1.27 1.20 1,07 1,62 1,60 1.26 1.43 1.35 1.00

The technical and economic effect obtained from the use of the adhesive composition is that its use can significantly improve the quality of fastening of vulcanized rubber products based on various rubbers.

Claims (1)

An adhesive composition including polychloroprene rubber Nairit DP, butylphenol formaldehyde resin 101K, water, zinc oxide, magnesium oxide, an organic solvent, which is a mixture of ethyl acetate and nefras, characterized in that it additionally contains a modifier previously obtained by reacting methylphosphite borate at room temperature and silica filler Rosil grade R-175 with a ratio of 7-3: 1, in the following ratio of components, parts by weight:
polychloroprene rubber nairit DP 90.0 101K butylphenol formaldehyde resin 90.0 water 3.0 zinc oxide 5,0 magnesium oxide 11.0 specified organic solvent 800,0 methyl phosphite borate 8.75-2.25 silica filler Rosil brand R-175 2.5-0.37