HU214782B - Process elastomeric materials vulcanised by sulphur composition and recycleted elastomeric materials - Google Patents

Abstract

The present invention relates to a process for the recovery of elemental sulfur-vulcanized elastomeric materials without the use of hexamethylene tetramine. The crosslinked sulfur-crosslinked elastomeric elastomer is treated with one or more known bovine preservatives (A) and one or more known boom preservatives (B), of which the bamboo enhancer may be a carbamate zinc salt and a dialkyl dithionic brine, 2-mercaptobenzothiazole or a derivative thereof, a thiuram derivative, a guanidine derivative, a 4,4'-dithiomorpholine derivative and a sulphenamide derivative, and the thickeners (A) and (B) are used in a molar ratio of 1: 1 to 1:12, and optionally zinc oxime as an activator in combination with stearic acid as a fatty acid stone activator, and the resulting regenerated elastomeric material can be cured without further addition of curing agents. ŕ

Description

The present invention relates to a process for the regeneration of elastomeric materials cured with elemental sulfur without the use of hexamethylene tetramine. The vulcanized cross-linked sulfur vulcanized elastomeric material is treated with one or more known rubber accelerators (A) and one or more known rubber accelerators (B), wherein the rubber accelerator (A) can be thiocarbamate zinc and dialkyldithiophosphate zinc salt and (B) can be 2-mercaptobenzothiazole or derivative thereof, thiuram derivative, guanidine derivative, 4,4'-dithiomorpholine derivative and sulfenamide derivative, and accelerators (A) and (B) are used in a molar ratio of 1: 1 to 1:12. and optionally employing zinc oxide as an activator as a fatty acid co-activator together with stearic acid, and the resulting regenerated elastomeric material can be vulcanized without the addition of further rubber vulcanizers.

The scope of the description is 8 pages

HU 214 782 B

HU 214 782 Β

BACKGROUND OF THE INVENTION The present invention relates to a process for the regeneration of elastomeric products made of natural rubber or synthetic rubber, such as tires, extruded products, gloves and webbing, which were originally cured with a conventional sulfur accelerated vulcanization system to recycle the recovered elastomeric material.

Recycling of recycled rubber from used rubber products is known in the industry, with about 200,000 tons of recycled rubber being processed each year. Conventional rubber regeneration uses high temperatures and catalysts to disintegrate the elastomeric material for reprocessing, which results in high energy consumption and significant degradation of the elastomeric material for reprocessing. The rubber thus regenerated has poor physical properties for subsequent use. It has a tensile strength of up to 5-6 MPa and a composition containing similar natural rubber has a tensile strength of more than 20 MPa. Conventional procedures are labor intensive, difficult, and difficult to carry out.

Examples of rubber regeneration processes include 2-mercaptobenzothiazole (International Polymer Science and Technology, Vol. 7, No. 6, 1980), thiuram compound (US-PS 4211676) and mercaptobenzothiazole (SU-PS 1620454).

Conventional rubber processing involves crushing the vulcanized rubber, then mixing the crushed rubber with a catalyst and exposing the resulting mixture to a temperature above 170 ° C for at least 4-6 hours in a digester. The resulting material is then massaged and then formed into a sheet. The resulting rubber products are used in small amounts as processing aids or diluents in the manufacture of fresh rubber products. The presence of reclaimed rubber in the blend adversely affects the physical and dynamic properties of the final vulcanized product.

Used tires and other rubber products cause environmental pollution. There is therefore a need for a regeneration process that addresses the growing environmental problems. Used tire tips are highly flammable. Many attempts have been made to mitigate this environmental hazard. These include the use of tire surfaces made of shredded tires for road surfacing, or the burning of such shredded rubber to generate energy.

The known methods have not provided a solution to overcome this problem.

Therefore, there is a need for a process by which the used rubber products can be effectively regenerated, which is economical and in which the bonds of the vulcanized crosslinked structure in the shredded rubber used are opened or the bonds are broken without degradation of the polymer backbone. The more the regenerated rubber retains the original physical and dynamic characteristics of the original natural or synthetic rubber, the more it can be used to make additional rubber products.

We have developed a process for converting a used rubber product, preferably a shredded rubber product, into an elastomeric material whose properties are similar to those of a fresh elastomer in similar compositions. The procedure is simple, not energy intensive and labor intensive.

A new method has been developed to increase the efficiency of the proton transfer reaction, which is considered essential. In our process, hexamine, which is difficult to handle and chemically dangerous, is not used. Instead, materials already used in the conventional rubber processing process are used. The present invention is based on the discovery of the use of a novel chemical mixture which is capable of initiating a proton exchange reaction in a controllable manner at a temperature below 70 ° C, preferably below 50 ° C, that is, it opens or terminates the vulcanized network of the elastomeric material.

The present invention thus relates to a process for the regeneration of sulfur-vulcanized elastomeric materials without hexamethylene-tetramine, wherein the vulcanized cross-linked sulfur-vulcanised elastomeric material is treated with one or more known rubber accelerators (A) and one or more known rubber accelerators (B). thiocarbamate zinc salt and dialkyl dithiophosphate zinc salt, and the rubber accelerator (B) may be 2-mercaptobenzothiazole or a derivative thereof, a thiuram derivative, a guanidine derivative, a 4,4'-dithiomorpholine derivative and a sulfenamide derivative, and (A). and (B) accelerators are used in a molar ratio of 1: 1 to 1:12 and optionally zinc oxide is used as activator together with stearic acid as a fatty acid coactivator to form a vulcanizable regenerated elastomeric material and the resulting regenerated elastomeric material can be vulcanized with further gum vulcanizing agent. without.

The accelerator combination initiates a bond breaking reaction at temperatures below 70 ° C, thereby opening and curing the vulcanized crosslinked structure.

The invention also relates to a composition for removing the crosslinking structure of a sulfur vulcanized elastomeric material.

The new composition (hereinafter referred to as "dressing composition") is in the form of a masterbatch and contains the following composition:

one or more gum accelerators (A) and one or more gum accelerators (B), wherein the gum accelerator (A) is a thiocarbamate zinc salt and a dialkyl dithiophosphate zinc salt, and the gum accelerator (B) is 2-mercapto-benzothiazole or a derivative thereof; , a guanidine derivative, a 4,4'-dithiomorpholine derivative and a sulfenamide derivative and an accelerating molar ratio of (A) and (B) of 1: 1 to 1:12 and optionally containing zinc oxide as an activator as a fatty acid activator together with stearic acid, and comprising an elastomeric material, wherein the weight ratio of the accelerator plus activator to the elastomeric material is from 40:60 to 90:10.

HU 214 782 Β

Conventional rubber accelerators, together with one or more activators initiating a proton exchange reaction at temperatures below 70 ° C, are capable of opening or removing the crosslinking structure of the sulfur-vulcanized elastomeric material to obtain a sulfur-vulcanizable regenerated elastomeric material.

The compound that acts as a rubber accelerator may be a zinc salt of thiocarbamates such as zinc dimethyldithiocarbamate (hereinafter ZDMC) and 2-mercaptobenzothiazole (hereinafter MBT) or derivatives thereof in a 1: 1 to 1:12 molar ratio. Accelerators are activated by one or more activators, preferably stearic acid or zinc oxide. Sulfur may also be added to the mixture.

Preferred accelerators are ZDMC and MBT, and can be replaced by other, less effective accelerators. The following are non-limiting examples of accelerators that can be used to replace ZDMC or MBT.

ZDMC can be substituted in molar amounts with dithiocarbamate zinc salts such as zinc diethyl dithiocarbamate (ZDEC), zinc dipropyl dithiocarbamate, zinc dibutyl thiocarbamate (ZBDC) or zinc dibenzyl dithiocarbamate (ZBEC), -dibutyl dithiophosphate or another compound that acts as a rubber accelerator.

MBT may be substituted in molar amounts by other thiazole type accelerators such as benzothiazole disulfide (MBTS) or zinc-2-mercaptobenzothiazole (ZMBT) or sulfenamide type accelerators such as N-cyclohexyl-2-benzothiazole sulfenamide (CBS), or N-tert-butyl 2-benzothiazole sulfenamide (TBBS) or thiuram-type accelerators such as tetraethylthiuram disulfide (TETD), tetramethylthiuram disulfide (TMTD) or tetrabenzylthiuram disulfide (TBETD) or accelerators such as duanidines, Ν, Ν'-diphenylguanidine, d-ortho-tolylguanidine, and 4,4'-dithiomorpholine, or other rubber accelerators.

Mixtures of MBT or MBT derivatives or other accelerators and ZDMC or ZDMC derivatives in molar ratios initiate a proton exchange reaction which may be facilitated by the presence of stearic acid and zinc oxide. Small amounts of sulfur may aid in vulcanization but do not require addition. The presence of walnuts in the powder dispersion is likely to activate the mixture, but its presence is not significant.

The new blend or debonding mixture may be mixed with shredded tire portions or other vulcanized elastomer shreds, preferably at a ratio of 6 parts by weight of decoupling composition to 100 parts by weight of rubber crumb on the roll, so that the vulcanized mesh structure will be curable. The total milling time is only 7-10 minutes and the process is preferably carried out at temperatures below 70 ° C. The binder and tire crumb can be first mixed in a mixer and subsequently processed in an open roller.

The dressing composition may be used in other ways, for example in the form of masterbatches. In this case, the binder composition is first mixed with fresh or vulcanized rubber, wherein the weight ratio of the binder composition to rubber is 90:10 to 40:60. This masterbatch may be blended with vulcanized rubber crumbs in a ratio such that the final ratio of rubber in the decoupling composition is 6: 100 parts by weight.

Some embodiments of the present invention are illustrated in the following Examples and Tables, and the properties of the formulations are illustrated to illustrate the practicability of the present invention.

Example 1

The following substances are mixed in the specified weight ratio:

2-mercapto-benzothiazole (MBT) 20.0 zinc dimethyl dithiocarbamate (ZDMC) 6.0 stearic 2.0 zinc oxide 2.0 sulfur 1.5 diethylene glycol 12.0 The powders are first thoroughly mixed with vigorous stirring.

stirring and then adding diethylene glycol to form a decoupling composition as a smooth paste.

500 grams of tire sponges are cured on a two-cylinder roller for 3 minutes and then 15 g of an antifoaming agent are added. After a further 2 minutes of grinding, an additional 15 g of a desiccant is added. A final milling of 2 minutes is then performed at a narrow opening. During this time, the composition can be turned into a sheet which is cured at 150 ° C for 15-30 minutes. The characteristics of the resulting vulcanized product obtained from tire fractures are shown in Table 1, showing products from Malaysia and Europe respectively.

Table 1

Characteristics of vulcanized products made from 100% natural rubber tire crumb

Song Country of Origin Malaysia Europe Features 1 2 3 4 First Size (mm) 0.1-0.5 0.1-0.5 0.1-0.5 > L o Second Amount of binder (part per 100 parts crumb) 6 6 6 6

HU 214 782 Β

Table 1 (continued)

Song Country of Origin Malaysia Europe Features 1 2 3 4 5th Voltage at 100% elongation (MPa) 3 3 3.5 5.5 6th Tensile strength (MPa) 12.1 12.7 14.5 16 7th Elongation at break 350 350 375 400 8th Residual elongation (%) 15 15 15 12 9th Relative concentration of chains, V _re i ^x 10 ⁴ (mol / cm ³ ) 1.1 1.2 1.2 1.3 10th High elasticity slip member, Α ^χ 10 ³ (MPa) (σ = 0.8 MPa) ** 0.5 0.5 0.4 0.4

* V _rel was calculated from the Mooney-Rivlin equation:

^rel RT (X-1A ² ) where

E is the voltage, 25 λ is the degree of elongation,

R is the gas constant and T is the temperature.

** The creep was calculated as follows:

D (σ, T) = D _o (σ, T) + A (σ, T) log _T + τ / η (σ, T) 30 where

D is the voltage (%), D _{o is} the initial voltage at τ = 1 minute (%)

A is the creep rate constant (1 / MPa) of the high elastic stress; 35 η is the viscosity (Pa's).

Example 2

The dressing composition of Example 1 is applied to a tire crumb and pelletized used glove pieces in a weight ratio of 6: 100 to the vulcanized crumb. The mastication and dressing release formulation was administered as in Example 1. The temperature of the roller chair shall not exceed 70 ° C. Total grinding time less than 10 minutes. Table 2 gives the characteristics of tire and glove crumb products. For comparison, the characteristics of products made from fresh rubber with filler (tire mix) and without filler (pure rubber mixture) are also given.

Table 2

Tire waste and glove waste product characteristics compared to fresh rubber products

Type of material Tire waste Gloves waste Fresh rubber (tire mix) Fresh rubber (rubber compound) Tensile strength (MPa) 13 14.5 18-21 21-23 Elongation (%) 300 600 300-500 700-800 Residual elongation (%) 10 15 - - Relative concentration of chains, V _re i ^x 10 (mol / cm ³ ) 1.4 0.6 - -

Example 3

In this example, the decoupling composition (Example 1) is mixed with fresh rubber, tire crumb and glove crumb to form a masterbatch containing 55 to 90% by weight of the decoupling composition and 50% by weight of the decoupling composition. The masterbatches are then introduced separately into the tire crumb and glove crumb according to Example 6Q of Example 1, except that for a masterbatch containing 90% wt. and, in the case of a 50% w / w master blend, 12 parts by weight are used, based on 100 parts by weight of the crumb. The properties of the products obtained are shown in Table 3.

HU 214 782 Β

Table 3

Characteristics of products made from masterbatches obtained using a decoupling composition

The type of masterbatch Fresh natural rubber: dressing 10: 901% Natural rubber: dressing 50: 501% Gloves: dressing 10: 901% Gloves: dressing 50: 501% Vulcanized waste tire- hoop glove tire- hoop glove tire- hoop glove tire- hoop glove Tensile strength (MPa) 11.5 17 11 10 10 13.5 12 10.5 Elongation at break (%) 250 860 250 610 250 780 320 600 Residual elongation (%) 5 10 6 15 10 10 6 15 Relative concentration of chains, V _re i ^x 10 ⁴ (mol / cm ³ ) 1.3 0.7 1.3 0.6 1.2 0.6 1.3 0.6

The foregoing examples demonstrate the versatility and effectiveness of the present invention in the preparation of rubber products recovered from natural or synthetic rubber vulcanizates or from a combination of natural and synthetic rubber vulcanizates.

The resulting reclaimed tires have appropriate physical and dynamic characteristics. Such formulations can be used directly in the manufacture of pressed products with fresh mixtures. By using regenerated elastomers, extrusion and vulcanization, such as tires, rugs, carpet mats, electrical insulating layers, industrial tires, hoses and new tires, can be made in conventional manner. 30

The process using the masterbatches can be further modified by using styrene-butadiene rubber instead of natural rubber. Controlling the process for incorporating the decoupling composition can improve the grinding process, improve the temperature used during the mastering process, and improve the physical and dynamic characteristics of the products recovered from the tire and glove waste formulation.

The following are examples of replacement of MBT with another accelerator.

Example 4

The following substances are mixed in the specified weight ratio:

Example 5 The following materials are mixed together the given weight ratio: 1. N-cyclohexyl-2-benzothiazole sulfenamide (CBS) 43.9 2. Zinc diethyl dithiocarbamate 7.6 3. Stearic acid 5.1 4. Zinc oxide 2.5 100 parts by weight of crumb tire and 12,5

To 10 parts by weight of crude natural rubber is added 10 parts of a decoupling composition as described in Example 1. The physical properties of the mixture are given in Table 5.

Table 5

Characteristics of the mixture using CGS when using raw natural rubber

Tensile strength (MPa) 11.1

Elongation at break (%) 369

300% elongation modulus (MPa) 7.9

Example 6

The following substances are mixed in the specified weight ratio of 40:

N-tert-butyl-2-benzothiazole sulfenamide

Benzothiazyl Disulfide (MBTS) 27.8 Zinc Diethyl Dithiocarbamate (ZDEC) 7.6 stearic 5.1 Zinc Oxide 2.5 100 parts by weight of crumb tire and

To 12.5 parts by weight of crude natural rubber is added 10 parts by weight of a decoupling composition as described in Example 1. The physical properties of the mixture are given in Table 4.

(TBBS) 39.8

2. Zinc Diethyl Dithiocarbamate (ZDEC) 7.6

3. Stearic acid 5.1

4. To zinc oxide 2.5 parts by weight of tire crumb and 12.5 parts by weight of raw natural rubber are added 10 parts by weight of a de-curing composition as described in Example 1. The physical properties of the mixture are given in Table 6.

Table 6

Characteristics of a mixture using TBBS when using raw natural rubber

Table 4

Characteristics of a mixture using MBTS when using raw natural rubber

Tensile strength (MPa) 10.0

Elongation at break (%) 336

300% elongation modulus (MPa) 5.6

Tensile strength (MPa) 12.0

Elongation at break (%) 353

Modulus of elongation at 300% (MPa) 9.3

In addition to the foregoing description of the invention, the process may be varied in various ways. These do not depart from the scope of the present invention.

HU 214 782 Β

Using the novel features of the present invention, a preferred method may be employed. It is noted that methacrylic acid may be used in addition to or instead of stearic acid. Alternatively, propylene glycol, dipropylene glycol or triethylene glycol or other suitable nuts can be used instead of diethylene glycol, which can be determined by a simple experiment.

Other compounds known to those skilled in the art may be used in place of the compounds which exemplify the foregoing rubber accelerators, and mixtures of such accelerators are within the scope of the present invention.

Other embodiments of the present invention will be described below whether or not they are specifically stated in the claims. For example, the "paste" of Example 1 can be varied by plus or minus 20%, preferably plus or minus 10%. Accordingly, the decoupling composition may comprise (a) ZDMC in an amount of 4.8-7.2 parts by weight and (b) MBT in an amount of 16-24 parts by weight. Preferably, the decoupling composition comprises both stearic acid and zinc oxide, in each case in an amount of 1.6 to 2.4 parts by weight. In addition, sulfur may be present in an amount of 1.2 to 1.8 parts by weight, and nuts, such as diethylene glycol, may be present in an amount of 9.6 to 14.4 parts by weight.

It is noted that the present invention includes the composition described above and may be a paste or a masterbatch.

PATENT CLAIMS

Claims (18)

PATIENT INDIVIDUAL POINTS A method for recovering elemental sulfur vulcanized elastomeric materials without the use of hexamethylene tetramine, characterized in that the vulcanized crosslinked sulfur vulcanized elastomeric material is treated with one or more known (A) rubber accelerators and one or more known (B) rubber accelerators, wherein (A ) rubber accelerator is thiocarbamate zinc salt and dialkilditiophosphate zinc salt, and the rubber accelerator (B) is 2-mercaptobenzothiazole or a derivative thereof, a thiuram derivative, a guanidine derivative, a 4,4'-dithiomorpholine derivative and a sulfenamide derivative; accelerators (A) and (B) are used in a molar ratio of 1: 1 to 1: 12, and optionally zinc oxide is used as an activator as a fatty acid co-activator with stearic acid, and the regenerated elastomer material thus obtained can be vulcanized without the addition of additional rubber vulcanizing agents. (Priority: 03/03/1995) 2. A method for regenerating elemental sulfur vulcanized elastomer materials without the use of hexamethylene tetramine, characterized in that the vulcanized cross-linked sulfur vulcanized elastomeric material is treated with one or more known (A) rubber accelerators and one or more known (B) rubber accelerators, wherein (A ) rubber accelerator is thiocarbamate zinc salt and dialkilditiophosphate zinc salt, and the rubber accelerator (B) is 2-mercaptobenzothiazole or a derivative thereof, a thiuram derivative, a guanidine derivative, a 4,4'-dithiomorpholine derivative and a sulfenamide derivative; accelerators (A) and (B) are used in a molar ratio of 1: 1 to 1: 12, and optionally zinc oxide is used as an activator as a fatty acid co-activator with stearic acid, and the regenerated elastomer material thus obtained can be vulcanized without the addition of additional rubber vulcanizing agents. (Topic 25/25/1994) 3. The method of claim 1, wherein (a) thiocarbamate zinc salt is zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dipropylthiocarbamate, zinc dibutyldithiocarbamate or zinc dibenzyldithiocarbamate and dialkyldithiophosphate. zinc dibutyldithiophosphate, (b) 2-mercaptobenzothiazole or a derivative of zinc mercapto-benzothiazole or benzothiazyl disulfide, (c) sulfenamid-2-benzothiazole sulfenamide or N-tert-butyl 2- (c) as zinc salt. benzothiazole sulphenamide, (d) teturethylthiuram disulfide, tetramethylthiuram disulfide or tetrabenzylthiuram disulfide as the thiuran derivative. (Priority: 03/03/1995) 4. The method of claim 2, wherein (a) the thiocarbamate zinc salt is zinc dimethyldithiocarbamate and (b) 2-mercaptobenzothiazole. (Topic 25/25/1994) 5. The method of claim 1, wherein the accelerators of the following two groups are used as accelerators (A) and (B): (A) zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dipropyldithiocarbamate, zinc dibutyldithiocarbamate or zinc dibenzyldithiocarbamate, and (B) 2-mercaptobenzothiazole, zinc mercaptobenzothiazole or benzothiazyl disulfide . (Priority: 03/03/1995) Method according to any one of claims 1, 3 or 5, characterized in that the smear is added to the other materials prior to the initiation of the initiation process. (Priority: 03/03/1995) Method according to any one of claims 1, 3, 5 or 6, characterized in that the accelerators (A) and (B) together with the zinc oxide are contacted with the sulfur-vulcanized elastomeric material in the form of a masterbatch comprising: a mixture of rubber accelerators and zinc oxide together with the elastomeric material, wherein the weight ratio of accelerators to zinc oxide to elastomeric material is 40: 60-90: 10. (Priority: 03/03/1995) 8. Method according to one of Claims 1 to 3, characterized in that the accelerator and activator mixture with the elastomeric material is 6 parts by weight The mixture is mixed in a ratio of 100 parts by weight of elastomeric material. (Priority: 03/03/1995) Method according to claim 8, characterized in that the masterbatch is used and the weight ratio of the masterbatch to the elastomeric material is 6: 100. (Priority: 03/03/1995) 10. Method according to any one of claims 1 to 3, characterized in that a material used as a vulcanized elastomeric material is used and the elastomeric material is derived from natural rubber, synthetic rubber or a mixture thereof. (Priority: 03/03/1995) 11. Method according to any one of claims 1 to 3, characterized in that the sulfur-vulcanized elastomeric material is used in shredded form. (Priority: 03/03/1995) 12. The method of claims 1, 3 or 5 to 11. Process for producing a product from a regenerated material according to any one of claims 1 to 5, characterized in that the regenerated elastomeric material is formed by mixing, pressing and / or vulcanizing, for example, a tire, carpet, carpet, electrical insulating parts or layers, industrial tires, hoses or new tires. (Priority: 03/03/1995) 13. A composition suitable for opening or curing a crosslinked structure of a sulfur-vulcanized elastomeric material in the form of a masterbatch comprising the following mixture: one or more known (A) rubber accelerators and one or more known (B) rubber accelerators; (A) rubber accelerator thiocarbamate zinc salt and dialkildithiophosphate zinc salt, and rubber accelerator (B) 2-mercaptobenzothiazole or a derivative thereof, a thiuram derivative, a guanidine derivative, a 4,4'-dithiomorpholine derivative and a sulfenamide derivative, and the accelerator molar ratio of (A) and (B) is from 1: 1 to 1:12, and optionally contains zinc oxide as an activator as a fatty acid co-activator with stearic acid and contains an elastomeric material, wherein the weight ratio of accelerator plus activator to elastomer material is 40: 60-90: 10th (Topic 25/25/1994) 14. A composition according to claim 13, wherein (a) thiocarbamate zinc salt is zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dipropyldithiocarbamate, zinc dibutyldithiocarbamate or zinc dibenzyldithiocarbamate and dialkyl. dithiophosphate zinc zinc dibutyldithiophosphate, (b) 2-mercaptobenzothiazole or its derivative zinc mercaptobenzothiazole or benzothiazyl disulfide, (c) the sulfenamide derivative is N-cyclohexyl-2-benzothiazole sulfenamide or N-tert-butyl-2 benzothiazole sulfenamide, (d) the thiuram derivative is tetraethylthiuram disulfide, tetramethylthiuram disulfide or tetrabenzylthiuram disulfide. (Topic 25/25/1994) 15. The composition of claim 13, wherein the accelerators (A) and (B) comprise accelerators of the following groups: (A) zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dipropyldithiocarbamate, zinc dibutyldithiocarbamate or zinc dibenzyldithiocarbamate, and (B) 2-mercaptobenzothiazole, zinc mercaptobenzothiazole or benzothiazyl disulfide . (Priority: 03/03/1995) 16. The composition of claim 11, wherein the accelerators (A) and (B) comprise the following accelerators: (A) zinc dimethyldithiocarbamate, and (B) 2-mercaptobenzothiazole. (Topic 25/25/1994) 17. References 13-16. Composition according to one of Claims 1 to 3, characterized in that the elastomeric material is fresh rubber or shredded material from a vulcanized product. (Topic 25/25/1994) A regenerated elastomeric material from elemental sulfur vulcanized elastomer material, characterized in that it is produced by the method of claim 2. (Topic 25/25/1994)