RU2559468C2 - Resin for increasing adhesiveness of rubber mixtures - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to obtaining resin for increasing adhesiveness of rubber mixtures and can be used in tyre and rubber industry. Resin contains, wt %: rosin - 55-70, eutectic melt of ε-caprolactam - 5-8 with N-isopropyl-N′-phenyl-n-phenylenediamine - 15-25 and zinc oxide - 7-15.

EFFECT: invention makes it possible to increase adhesiveness of rubber mixtures in duplicating and adhesion of rubber to metal, with resin-containing vulcanisates containing high protective action against thermooxidising and ozone ageing.

3 tbl, 7 ex

Description

The invention relates to the production of resins to increase the stickiness of rubber compounds and can be used in the tire and rubber industry.

Known resins for these purposes relate to products of synthetic and natural origin [Makhlis F.A., Fedyukin D.L. Rubber Terminology: Ref. Ed. - M.: Chemistry, 1989. - 400 p.].

Synthetic resins are known, mainly represented by alkyl-formaldehyde, alkylphenol-formaldehyde sulfide, xylene and terpene oligomeric products [Makhlis F.A., Fedyukin D.L. Rubber Terminology: Ref. Ed. - M .: Chemistry, 1989, 405 pp.].

They have a common drawback - when used in rubber compounds, they have a significant effect on the vulcanization of rubbers. For example, increasing or decreasing the start time of vulcanization due to inconsistent molecular weight, they require a fairly frequent adjustment of the vulcanizing group, which, accordingly, negatively affects the stability of the technological process for the production of tires and rubber products.

The most commonly used in the tire and rubber industries is the икар Picard ’hydrocarbon resin. The resin is a derivative of the unsaturated fraction of C ₅ and maleic anhydride. For the synthesis of ″ Picard ″ resin [TU 2451-010-54861661-2003], the interaction of by-products of the synthesis of isoprene from isobutylene and formaldehyde with maleic anhydride was used , products ″ / Ukr. Gos. University of Chemical Technology. Dnepropetrovsk, 2002. - p. 54-55].

The specified resin does not provide the necessary stickiness of the rubber compounds.

Natural resins include petroleum refining products - petroleum polymer resins, for example Piroplast resin [TU 220-00 / 505 18328-05].

These resins also do not provide the necessary adhesion to rubber compounds.

It is known that rosin is used in herbal compounds from herbal products [Rubber Handbook. Rubber production materials. M .: Chemistry, 1971, 608 pp.].

But the use of rosin to increase tack in the cold period of the enterprise becomes problematic due to the fact that it migrates to the surface and goes into a glassy state, losing its functional properties.

The most widely known type of rosin is pine gum [Komshilova N.F. Rosin, its composition and structure of resin acids. ″ Forest industry ″, 1980, p.17-18].

However, due to an increase in the cost of raw materials for producing pine resin, its production is constantly decreasing.

Along with pine gum rosin, modified products based on extraction rosin, in particular KEMON resin, which is a product of modification of the extraction rosin of alkyl phenolamine resin, are also used as a tackifier for rubber compounds [Romanina T.A. KEMON resin is a new type of modified extraction rosin. - Hydrolysis and wood chemical industry, 1989, No. 2, p. 11].

However, as shown by the practice of the tire industry and rubber products, this resin is heterogeneous in composition and sometimes it negatively affects the strength properties of rubber.

Also used in production is the modified extraction rosin EM-3 [Zykova N.P. Obtaining rosin EM-3 and its use in the production of tires and rubber products. Hydrolysis and forest chemical industry, 1979, No. 6, pp. 14-15], which is a product of the modification of extraction rosin with maleic anhydride and formaldehyde.

However, due to a sharp increase in the cost of production, the production of extraction rosin and products based on it (EM-3 rosin and KEMON resins) was discontinued.

In order to expand the range of tackifiers for rubber compounds, tall oil rosin modified with maleic anhydride and formaldehyde can be used when heated in the presence of 0.02-0.05% by weight of rosin of dimethylpolysiloxane with a viscosity of 200-400 m ² / s [RU patent No. 2130042 IPC C09F 1/04, published 05/10/1999].

But this resin does not provide the necessary level of stickiness of rubber compounds and is available in the form of a monolith. Moreover, the production method involves the use of solvents (xylene, toluene), which leads to a deterioration in the environmental parameters of the process of obtaining the product.

Known technological additive obtained on the basis of the product of distillation of tall oil - tall pitch, as well as tall pitch modified with HMT [Tall products and the possibility of their use in the formulation of rubber mixtures, "Forest chemistry and tapping", vol. 1, M., 1987].

But it does not provide a sufficiently high level of stickiness and the necessary viscosity of rubber compounds. In addition, the high content of volatile components with a strong unpleasant odor in it sharply affects the consumer properties of the product and negatively affects the environmental conditions of production and the environment.

Also, to increase the stickiness, rosin resin is used, which is a mixture of tall oil rosin and tall pitch, taken in a mass ratio (10-90) :( 90-10) in an amount of 100 parts by weight, formalin or paraform, or fumaric as a modifying agent acid, or maleic acid, or maleic anhydride in an amount of 0.5-10 parts by weight, the resin obtained in the presence of calcium oxide in an amount of 1.0-10.0 parts by weight [Patent RU No. 2229491 IPC C09F 1/00, published May 27, 2004].

The disadvantage of this rosin resin is the lack of stickiness, a complex production process, requiring large energy costs and special equipment.

Closest to the claimed invention is a tackifying resin containing rosin - 30.00-40.00 wt.%, Eutectic melt of ε-caprolactam with N-isopropyl-N′-phenyl-n-phenylenediamine - 5.00-10, 00 wt.%, Oil-polymer resins - 30.00-40.00 wt.% And protective wax - 15.00-25.00 wt.% [Patent RU No. 2464291, IPC C09F 1/04, C09J 11/06, published 10/20/2012].

The disadvantage of this resin is the low adhesion tack of rubber compounds.

The objective of the invention is to obtain a resin that increases the stickiness when duplicating rubber compounds and when bonding rubber with metal, while maintaining the physico-mechanical properties of the vulcanizates.

The technical result is a resin having a high adhesive tack during duplication of rubber compounds and adhesion of rubber to metal. In addition, vulcanizates containing the inventive resin have a high protective effect against thermal oxidative and ozone aging.

The technical result is achieved in a resin to increase the stickiness of rubber mixtures containing rosin, a eutectic melt of ε-caprolactam with N-isopropyl-N′-phenyl-n-phenylenediamine, characterized in that the resin contains zinc oxide in the following ratio of components, wt. %:

Rosin 55.00-70.00 ε-caprolactam 5.00-8.00 N-isopropyl-N′-phenyl-n-phenylenediamine 15.00-25.00 Zinc oxide 7.00-15.00

The increased properties of confection stickiness in the proposed technical solution are achieved by introducing zinc oxide into the resin composition at the indicated mass ratio. The introduction of zinc oxide increases the thermal oxidative and ozone resistance of vulcanizates. This alloy does not crystallize and remains liquid according to Brookfield 450-700 cP at temperatures above minus 18 ° C.

In the process of obtaining the claimed resin, zinc oxide interacts with the fatty acids that make up the rosin. The zinc salts formed in this process form a molecular complex with ε-caprolactam in the ligand sphere [Puchkov AF, Talbi EV, Turenko SV // Rubber and rubber. 2008, No. 2, p. 23]. This ensures the stickiness of rubber compounds while maintaining technological properties (viscosity). Under the action of zinc oxide, rosin unsaturation is halved, which also contributes to an increase in resistance to thermooxidative and ozone aging of vulcanizates (unsaturation was determined by the method of iodine numbers and unsaturated hydrocarbon content [GOST 2070-82]).

The tackifying resin is prepared as follows:

- ε-caprolactam and N-isopropyl-N′-phenyl-n-phenylenediamine are loaded into a reactor heated to a temperature of 80 ° C and mixed with a paddle mixer for 25 minutes;

- after the formation of a double eutectic melt, the temperature is increased to 120-125 ° C and rosin is added in small portions. Each subsequent portion of rosin is introduced after the previous melting. In this case, a triple eutectic melt is formed.

- zinc oxide is added last, mixed for 40-60 minutes until the gas evolution stops.

The resin is a black viscous liquid that is discharged into a receiving container. When cooled to room temperature, the resin solidifies; this product is convenient for storage and transportation.

Rosin is used according to GOST 19113-84.

Σ-caprolactam - GOST 7580-86.

N-isopropyl-N′-phenyl-n-phenylenediamine - IPPD is a Chinese or Slovak product manufactured by Duslo.

Zinc oxide - GOST 10262-73.

 Table 1 shows the compositions of the resins.

Resins with the composition 1, 2, 4 do not meet the stated requirements or do not ensure the manufacturability of the product:

Composition 1 - the low content of zinc oxide does not provide sufficient resistance of the vulcanizates to thermal oxidative and ozone aging.

Compositions 2, 4 are not technologically advanced due to the excessive viscosity of the resin.

Selected component ratio range:

ε-caprolactam - 5-8 wt.%, N-isopropyl-N′-phenyl-n-phenylenediamine - 15-25 wt.% in this case is optimal, since it allows you to create a dispersion medium with the required viscosity, in which it is distributed homogeneously rosin. The system as a whole, consisting of the eutectic melt of ε-caprolactam - N-isopropyl-N′-phenyl-n-phenylenediamine in the stated ratio and rosin, has the necessary viscosity for the synthesis of the resin.

When the content of zinc oxide is less than 5 wt.%, The resistance to aging of the resin is not enough. When the content of zinc oxide is more than 15 wt.% - the reaction mass is excessively viscous, which is unacceptable due to problems encountered in unloading the product from the reactor.

A decrease in rosin (less than 55 wt.%) Leads to a decrease in the stickiness of the rubber blanks, and, conversely, an increase in the rosin content in the resin (more than 70 wt.%) Leads to a significant increase in the viscosity of the mixture, which complicates the process.

The compositions of the rubber compounds are presented in table. 2. Control rubber mixture - a mixture containing rosin used in the tread of an agricultural tire, prototype - a rubber mixture using a resin to increase the tack of the rubber compounds of the prototype, experimental 3, 5, 6 and 7 rubber compounds - which include the inventive resin to increase the tack obtained according to the recipes of the resin 3, 5, 6 and 7, respectively (see table 1).

In experimental rubber mixtures, rosin and prototype were replaced with the claimed resin of compositions 3, 5, 6 and 7.

The property of rubber compounds and vulcanizates - stickiness was evaluated according to the method proposed by Moncanto, on the device "Tel-Tak". The property of vulcanizates according to GOST 270-74 and GOST 270-75.

From the table. 3 shows that the use of the claimed resin has a significant effect on the stickiness of the rubber compounds. The increase in the stickiness of the rubber compounds experienced 3, 5, 6 and 7 compared with the rubber mixture of the prototype can reach 53% when duplicating mixtures. Experimental mixtures 3, 5, 6, and 7 also increase the adhesion of rubber to metal compared to a rubber composition containing rosin by 83%. Also, in comparison with the control rubber compound, the experimental 3, 5, 6 and 7 mixtures have a higher degree of thermo-oxidative and ozone resistance.

Example 1. In a stirred reactor at a temperature of 80 ° C, ε-caprolactam 61.5 g and N-isopropyl-N′-phenyl-n-phenylenediamine 30.8 g are charged. After the formation of a double eutectic melt, the temperature is raised to 120-125 ° Rosin 200.0 g is added with small portions. When preparing the resin, the ε-caprolactam alloy with N-isopropyl-N′-phenyl-n-phenylenediamine should be collected in an amount sufficient to completely immerse the first portion of rosin. Each subsequent one is introduced after the previous one is melted. The last introduced zinc oxide is 15.4 g. The composition is mixed, after cooling it is discharged from the reactor.

Example 2. Analogously to example 1, with the difference that the component downloads contain ε-caprolactam 31.8 g, N-isopropyl-N′-phenyl-n-phenylenediamine 63.7 g, rosin 200 g, zinc oxide 22.9 g.

Example 3. Analogously to example 1, characterized in that they contain ε-caprolactam 22.9 g, N-isopropyl-N′-phenyl-n-phenylenediamine 45.8 g, rosin 200 g, zinc oxide 21.2 g

Example 4. Analogously to example 1, with the difference that the component downloads contain ε-caprolactam 55.9 g, N-isopropyl-N′-phenyl-n-phenylenediamine 111.9 g, rosin 300 g, zinc oxide 40.7 g.

Example 5. Analogously to example 1, characterized in that they contain ε-caprolactam 27.3 g, N-isopropyl-N′-phenyl-n-phenylenediamine 136.3 g, rosin 300 g, zinc oxide 81.8 g

Example 6. Analogously to example 1, characterized in that they contain ε-caprolactam 40 g, N-isopropyl-N′-phenyl-n-phenylenediamine 125 g, rosin 300 g, zinc oxide 35 g.

Example 7. Analogously to example 1, characterized in that they contain ε-caprolactam 21.4 g, N-isopropyl-N′-phenyl-n-phenylenediamine 64.3 g, rosin 300 g, zinc oxide 42.9 g.

Thus, the inventive resin increases the confectionary tack of rubber compounds and can be used as an antioxidant of the vulcanizate.

Claims (1)

Resin for increasing the stickiness of rubber compounds containing rosin, eutectic melt of ε-caprolactam with N-isopropyl-N′-phenyl-n-phenylenediamine, characterized in that the resin contains zinc oxide in the following ratio, wt.%:
rosin 55-70 ε-caprolactam 5-8 N-isopropyl-N′-phenyl-n-phenylenediamine 15-25 zinc oxide 7-15