RU2279448C1 - Method of production of rubber mix on base of chloroprene rubber for adhesive composition - Google Patents

Abstract

FIELD: rubber industry; methods of production of rubber mix on base of chloroprene rubber for preparation of cold-setting adghesives.

SUBSTANCE: chloroprene rubber of NYRIT KPHT grade is subjected to steam heating before mixing with zinc oxide and magnesium oxide; steam heating is continued for an hour at temperature of 100°C, after which mix is subjected to rolling till rubber sheet is formed. Then, diphenyl guanidine is introduced and mix is rolled, after which modifying agent is introduced; modifying agent is obtained preliminarily through interaction of epoxy diane resin and stillage waste of aniline process at mass ratio of 2:1 and content of aniline of 15-18 parts by mass. Rubber mix is used for making adhesive composition with the use of solvent and resin 101K. This adhesive composition enhanced quality of attachment of rubber to rubber and to metal.

EFFECT: utilization of petrochemical process waste - aniline.

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Description

The invention relates to the rubber industry, in particular to a method for producing a rubber mixture based on chloroprene rubber, which can then be used to produce cold cured adhesives.

A known method of producing a rubber mixture by mixing chloroprene rubber with a vulcanization accelerator, an antioxidant, a vulcanizing group, plasticizers, a dispersant, a modifier, active fillers and a fibrous filler in a rubber mixer with subsequent processing of the mixture on rollers and vulcanization (USSR Author's Certificate No. 1063809, class 08 J C 08 J 3/28; Publ. 30.12.83).

However, this method requires processing the rubber mixture on the rollers in the field of a pulsed electromagnetic discharge.

A known method of producing a rubber mixture by mixing chloroprene rubber with soot, followed by dilution of the resulting composition with a polymer and the introduction of the components of the rubber mixture (USSR Author's Certificate No. 979399; class 08 J 3/22; Publish. 07.12.82).

However, in this method, dilution of the mixture with styrene-butadiene thermoplastic elastomer is required, which makes the rubber compound more expensive.

A known method of obtaining a rubber mixture based on unsaturated rubber by mixing rubber with a modifier on the rollers and the introduction of target additives (USSR Author's Certificate No. 956498, class 08 J 3/20; Publish. 07.09.82).

However, in this method, energy costs are increased by grinding the mixture with a single pass through a hammer mill.

A known method of producing a rubber mixture for cable sheaths by mixing chloroprene rubber, mercaptobenzthiazole, stearic acid, paraffin, phenyl-β-naphthylamine, dibutyl phthalate, chalk, kaolin, carbon black, magnesium oxide and zinc oxide (USSR Copyright Certificate No. 1608198, class 08 08, class. C 08 J 3/28; Publ. 23.11.90).

However, in this method, it is necessary to process zinc oxide and magnesium oxide before mixing to process laser radiation.

The closest is a method of producing a rubber mixture based on chloroprene rubber for an adhesive composition (cold curing), including plasticizing the rubber, then mixing the rubber on rollers with magnesium oxide and zinc oxide at the specified ratio of components, followed by preparation of the adhesive composition with the addition of alkyl phenol formaldehyde resin and solvent ( USSR author's certificate No. 1279993, class C 09 J 3/12; Publ. 30.12.86).

However, with this method of producing a rubber mixture, the adhesive composition based on it has low strength characteristics.

Objective: to develop a method for producing a rubber mixture based on chloroprene rubber with utilization of petrochemical production waste (aniline), which can be used to produce adhesives.

The technical result is the development of a method of producing a rubber mixture based on chloroprene rubber, with the disposal of waste petrochemical production (aniline).

The technical result achieved is achieved in that a method for producing a rubber mixture based on chloroprene rubber for an adhesive composition, comprising mixing rubber with zinc oxide and magnesium oxide, characterized in that rubber NIRIT KRNT is used as chloroprene rubber and before mixing with magnesium oxide and oxide zinc is steamed rubber at 100 ° C for 1 hour, then rolling to the formation of the skin, then enter diphenylguanidine followed by rolling, after which modificato p, previously obtained by the interaction of the epoxy Dianova resin ED-20 with bottoms waste production of aniline in a mass ratio of 2: 1 at 150 ° C for 5 hours, while bottoms waste contains 15-18 wt.h. aniline, in the following ratio of the components of the rubber mixture, parts by weight: chloroprene rubber Nairit KRNT - 100, diphenylguanidine - 0.5, zinc oxide - 5, magnesium oxide - 12, epoxy Dianova resin ED-20 - 3.33-10, 0, bottoms waste from the production of aniline - 1.67-5.0.

Chloroprene rubber Nairite KRNT (TU 6-01-1297-86).

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

Diphenylguanidine is an effective chemical plasticizer for chloroprene rubbers (Koshelev F.F. et al. General technology of rubber. M: Chemistry, - 1978).

The modifier is obtained by direct interaction of the ED-20 epoxy diane resin with bottoms from aniline production in a mass ratio of 2: 1, at 150 ° C for 5 hours. The modifier is fragile granules of irregular shape and is a cheap substance, since KPA are waste generated during the production of aniline (TP production of aniline, ZAO "Orgsintez" Volzhsky, stage of separation of commodity aniline). KPA are (mass parts): aniline - 15-18, cyclohexylamine - 0-10, toluidine (solvent) - 2-4, sodium hydroxide (filler) - 1-3, diphenylamine - 3-20, metaphenyldiamine - 1 -3, o-, n-aminophenol - 1-6, high molecular weight resinous substances (reagents interacting with rubber) - 6-45.

When using ED-20 epoxy resin and modifier waste aniline as a modifier in a mass ratio of 2: 1, the adhesive properties of the rubber compound, which can be used to obtain an adhesive composition, increase. When the ratio of modifier components changes, it becomes viscous, which makes it difficult to introduce it into the rubber mixture, while the adhesive properties of the rubber mixture are reduced.

The rubber mixture is prepared as follows. First, the rubber is steamed for 60 minutes at a temperature of 100 ° C. Then prepare the rubber mixture (a mixture of Nairite KRNT, diphenylguanidine, pre-obtained modifier, magnesium oxide, zinc oxide) on the rollers for 90 minutes.

An example of the preparation of a rubber compound.

Steaming crystallized rubber of Nairite KRNT for 60 minutes at a temperature of 100 ° C. Cooling steamed rubber to 50-60 ° C. Rolling rubber for 20 minutes (until skin is formed). Administration of diphenylguanidine and rolling for 10 minutes. The introduction of the previously obtained modifier and rolling for 10 minutes. The introduction of magnesium oxide and rolling for 10 minutes. The introduction of zinc oxide and rolling for 10 minutes. Rolling the finished rubber compound for 30 minutes.

Get rubber mixture 1-3, the compositions of which are shown in table 1.

After preparation, the rubber mixtures are crushed and with a part of the solvent (about 0.1 part of the total amount of solvent) are loaded into the glue mixer. The remaining amount of solvent, together with butylphenol formaldehyde resin 101 K, is loaded in portions into the glue mixer as the rubber mixture swells. The total adhesive mixing time is 4.5-5 hours.

Recipes of adhesive compositions 1-3 are presented in table 2.

Table 3 shows the strength properties of adhesive compositions based on the proposed rubber compounds for bonding vulcanized rubber based on SKI-3. The proposed compositions were tested for adhesive shear strength, achieved when kept under a load of 2 kg, at room temperature (20 ° C) for 24 hours. The data are presented in table 3, which shows that the best results were obtained using the composition of composition 2.

The declared limits of the components that make up the ED-20 modifier are 3.33-10.0; KPA 1.67-5.0, due to the fact that with an increase or decrease in these dosages, the adhesive strength during bonding decreases.

It has been established that the content of modifier components is the most optimal: epoxy resin ED-20 - 6.67 and KPA - 3.33, with the introduction of which the best results were obtained.

In further studies, composition 2 was used.

Tests of adhesive compositions were carried out by bonding vulcanized rubber samples based on SKI-3, SKEP, SKN to each other. Shear adhesion was determined on an MPC-250 tensile testing machine (GOST 16971-71). 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. Tests of adhesive compositions were also carried out when attaching rubber based on SKI-3, SKEP and SKN to steel (Art. 3). Adhesion was determined by peeling. Strength at uniform separation was determined on the adhesion meter PSO MG4 (TU 4271-005-12585810-01).

Comparative tests of the strength properties of the composition of compositions 2 are presented in table 4, which shows that the adhesive composition 2 provides an increase in the strength properties of adhesive joints. So the strength of the adhesive joint in shear when bonding vulcanized rubber based on SKI-3 using the proposed modifier of 1.2 MPa.

We found that the reason for the increase in adhesive performance of the adhesive is not only an increase in the concentration of polar groups when introduced into the composition of the modifier, but also the formation of additional chemical bonds during the interaction of the amino-containing modifier with mobile allylic chlorine atoms in the macromolecules of chloroprene rubber. Which leads to an increase in the density of the spatial grid and, apparently, to hardening of the adhesive film.

Table 1 Mixture components The content of the components of the mixture in the compositions, parts by weight one 2 3 Chloroprene rubber Nairite KRNT 100.00 100.00 100.00 Zinc oxide 5.00 5.00 5.00 Magnesium oxide 12.00 12.00 12.00 Diphenylguanidine 0.50 0.50 0.50 Epoxy resin ED-20 3.33 6.67 10.00 KPA 1,67 3.33 5,0

table 2 Component The content of components, mass. hours in composition one 2 3 Chloroprene rubber nairit KRNT one hundred one hundred one hundred Butylphenol formaldehyde resin 101 K 110 110 110 Diphenylguanidine 0.5 0.5 0.5 Zinc oxide 5 5 5 Magnesium oxide 12 12 12 Organic solvent (a mixture of ethyl acetate and nefras in a percentage of 50:50) 960 960 960 ED-20 3.33 6.67 10.00 KPA 1,67 3.33 5,0

Table 3 Shear Strength, MPa Metric for composition one 2 3 24 h 1,1 1,2 1,1

Table 4 Substrate Type Metric for composition The proposed composition Shear Strength, MPa SKI-3 1,2 SKEP 1,6 SKN 1.3 Tear strength, MPa SKI-3-St.3 1.4 SKEP-St.3 2.7 SKN-St.3 0.9

The technical and economic effect obtained from the application of the method of producing a rubber mixture based on chloroprene rubber for an adhesive composition is that its application can significantly improve the quality of fastening products from vulcanized rubber based on various rubbers and when it is attached to a metal surface, to improve technological bonding process parameters. In addition, its use allows the use of a by-product (waste) of petrochemical production (aniline).

Claims (1)

A method of producing a rubber mixture based on chloroprene rubber for an adhesive composition, comprising mixing rubber with zinc oxide and magnesium oxide, characterized in that rubber NIRIT brand is used as chloroprene rubber, and before mixing with magnesium oxide and zinc oxide, the rubber is steamed at a temperature of 100 ° C for 1 h, then rolling to the formation of a skin, then diphenylguanidine is introduced, followed by rolling, after which a modifier, previously obtained by the interaction of ep ksidnoy bisphenol resin ED-20 production waste vat aniline in a weight ratio of 2: 1 at 150 ° C for 5 hours, the vat waste contains 15-18 parts by weight aniline, in the following ratio of components of the rubber mixture, parts by weight: Chloroprene rubber Nairite KRNT one hundred Diphenylguanidine 0.5 Zinc oxide 5 Magnesium oxide 12 Epoxy Dianovy resin ED-20 3.33-10.0 VAT waste aniline production 1.67-5.0