阅读说明：本技术 一种硫化橡胶再生胶及其制备方法 (Vulcanized rubber reclaimed rubber and preparation method thereof ) 是由 贾新江 李新强 刘刚 于 2020-12-18 设计创作，主要内容包括：本发明涉及一种硫化橡胶再生胶及其制备方法。硫化橡胶再生胶包括橡胶、硫化剂、防老剂以及再生剂,其中所述硫化剂包括硫磺,所述防老剂为N-环己基-N’-苯基对苯二胺、9,9-二甲基吖啶、2-巯基苯并咪唑中的一种或多种,所述再生剂包括3,6-二氧杂-1,8-辛烷二硫醇。本发明硫化橡胶再生胶可以在低温下选择性断裂硫化橡胶中的硫硫键,且用量少,成本低,而且得到的再生胶分子量高,实现在相对较低的温度下交联网络不会出现断链。而且显著提高了硫化橡胶再生胶的物理机械性能差、隔音性能。(The invention relates to vulcanized rubber reclaimed rubber and a preparation method thereof. The vulcanized rubber reclaimed rubber comprises rubber, a vulcanizing agent, an anti-aging agent and a regenerating agent, wherein the vulcanizing agent comprises sulfur, the anti-aging agent is one or more of N-cyclohexyl-N' -phenyl-p-phenylenediamine, 9-dimethylacridine and 2-mercaptobenzimidazole, and the regenerating agent comprises 3, 6-dioxa-1, 8-octane dithiol. The vulcanized rubber reclaimed rubber can selectively break sulfur-sulfur bonds in vulcanized rubber at low temperature, has low consumption and low cost, and the obtained reclaimed rubber has high molecular weight, so that the crosslinked network can not be broken at relatively low temperature. But also remarkably improves the poor physical and mechanical properties and the sound insulation property of the vulcanized rubber reclaimed rubber.)

1. The vulcanized rubber reclaimed rubber is characterized by comprising rubber, a vulcanizing agent, an anti-aging agent and a regenerating agent, wherein the vulcanizing agent comprises sulfur, the anti-aging agent is one or more of N-cyclohexyl-N' -phenyl-p-phenylenediamine, 9-dimethylacridine and 2-mercaptobenzimidazole, and the regenerating agent comprises 3, 6-dioxa-1, 8-octane dithiol.

2. The reclaimed vulcanized rubber according to claim 1, wherein the rubber comprises at least one of natural rubber, styrene-butadiene rubber, butadiene rubber and isoprene rubber.

3. The vulcanized rubber vulcanizate of claim 1, wherein the rubber comprises nitrile rubber or neoprene rubber.

4. The vulcanized rubber reclaimed rubber according to claim 1, further comprising a carbon black agent, wherein the carbon black agent is one or more of carbon black N219 and white carbon black.

5. The vulcanized rubber vulcanizate of claim 1, further comprising a catalyst, wherein the catalyst is one or more of tetramethylthiuram disulfide, ethylene thiourea, and 2, 2' -dithiodibenzothiazyl.

6. The vulcanized rubber reclaimed rubber according to claim 1, further comprising an active agent, wherein the active agent is one or more of stearic acid, zinc oxide and magnesium oxide.

7. The vulcanized rubber reclaimed rubber according to claim 1, further comprising a dispersant, wherein the dispersant comprises dioctyl ester.

8. The reclaimed vulcanized rubber according to claim 1, further comprising one or more of mica powder, hollow glass beads or montmorillonite.

9. A method for preparing a vulcanized rubber vulcanizate according to claim 1, comprising the steps of:

preparing vulcanized rubber, namely adding rubber into the vulcanizing agent to form vulcanized rubber; the rubber comprises at least one of natural rubber, styrene butadiene rubber, butadiene rubber and isoprene rubber; the vulcanizing agent comprises sulfur;

an anti-aging agent adding step, namely adding the anti-aging agent into the vulcanized rubber, wherein the anti-aging agent is one or more of N-cyclohexyl-N' -phenyl-p-phenylenediamine, 9-dimethylacridine and 2-mercaptobenzimidazole; and

a regenerant adding step, namely placing the vulcanized rubber added with the anti-aging agent in a solvent for full swelling, adding the regenerant, standing to obtain regenerated rubber sol, heating and preserving heat, and removing the solvent to obtain vulcanized rubber regenerated rubber; wherein, the regenerant comprises 3, 6-dioxa-1, 8-octane dithiol, and the solvent is at least one of toluene and xylene.

10. The method of claim 9, wherein in the step of adding the recycling agent, after the heating and the holding, methanol is added to the solution for flocculation, and flocs are taken out and dried at 50-70 ℃ for 1-2 days to remove the solvent.

Technical Field

The invention belongs to the technical field of rubber composite material preparation, and particularly relates to vulcanized rubber reclaimed rubber and a preparation method thereof.

Background

As is well known, China is a large rubber using country, and is also the largest waste tire generating country in the world, the generation amount of waste tires in China in 2017 is about 3.4 hundred million, and a large amount of waste tires in China are accumulated for a long time, so that not only is the resource waste caused, but also a large amount of land is occupied, and the serious environmental pollution is caused. Therefore, it is very important to find a comprehensive utilization mode of the waste tires, reduce the external dependence of rubber resources, improve the utilization degree of the waste rubber and realize high-quality recovery.

A method for continuously preparing reclaimed rubber by a double-stage double-screw extruder is provided, and the method for desulfurizing and regenerating vulcanized rubber by the double-screw extruder is a physical and chemical method combined recovery method. The high-temperature high-shear of the double screw rod replaces a high-temperature high-pressure dynamic devulcanizer to realize the devulcanization regeneration of the rubber. The double-screw extrusion regeneration process has the characteristics of continuity, tightness, no pollution and the like, but the content and the molecular weight of the regenerated collosol produced by the process are lower.

The research shows that dithiothreitol has better selective reduction activity at lower temperature, can better selectively break sulfur-sulfur bonds, and shows better selective breaking performance at lower temperature, and through the function, the decrosslinking of vulcanized rubber at low temperature can be effectively realized. However, dithiothreitol is expensive and not suitable for industrialization.

And the existing vulcanized rubber reclaimed rubber also has the technical problems of poor physical and mechanical properties and poor sound insulation performance.

Disclosure of Invention

The invention aims to provide vulcanized rubber reclaimed rubber and a preparation method thereof, which are used for solving the technical problems that the existing vulcanized rubber has broken chains in a cross-linked network at a lower temperature and the existing vulcanized rubber reclaimed rubber has poor physical and mechanical properties and poor sound insulation properties.

In order to achieve the above object, the present invention provides a vulcanized rubber reclaimed rubber, comprising rubber, a vulcanizing agent, an anti-aging agent and a reclaiming agent, wherein the vulcanizing agent comprises sulfur, the anti-aging agent is one or more of N-cyclohexyl-N' -phenyl-p-phenylenediamine, 9-dimethylacridine and 2-mercaptobenzimidazole, and the reclaiming agent comprises 3, 6-dioxa-1, 8-octane dithiol.

Further, the rubber comprises at least one of natural rubber, styrene-butadiene rubber, butadiene rubber and isoprene rubber.

Further, the rubber includes nitrile rubber or chloroprene rubber.

Further, the vulcanized rubber reclaimed rubber also comprises a carbon black agent, wherein the carbon black agent is one or more of carbon black N219 and white carbon black.

Further, the vulcanized rubber reclaimed rubber also comprises a catalyst, wherein the catalyst is one or more of tetramethylthiuram disulfide, ethylene thiourea and 2, 2' -dithiodibenzothiazyl.

Further, the vulcanized rubber reclaimed rubber also comprises an active agent, wherein the active agent is one or more of stearic acid, zinc oxide and magnesium oxide.

Further, the vulcanized rubber reclaimed rubber also comprises a dispersing agent, and the dispersing agent comprises dioctyl phthalate.

Further, the vulcanized rubber reclaimed rubber also comprises one or more of mica powder, hollow glass beads or montmorillonite.

The invention also provides a preparation method of the vulcanized rubber reclaimed rubber, which comprises the following steps:

preparing vulcanized rubber, namely adding rubber into the vulcanizing agent to form vulcanized rubber; the rubber comprises at least one of natural rubber, styrene butadiene rubber, butadiene rubber and isoprene rubber; the vulcanizing agent comprises sulfur;

an anti-aging agent adding step, namely adding the anti-aging agent into the vulcanized rubber, wherein the anti-aging agent is one or more of N-cyclohexyl-N' -phenyl-p-phenylenediamine, 9-dimethylacridine and 2-mercaptobenzimidazole; and

a regenerant adding step, namely placing the vulcanized rubber added with the anti-aging agent in a solvent for full swelling, adding the regenerant, standing to obtain regenerated rubber sol, heating and preserving heat, and removing the solvent to obtain vulcanized rubber regenerated rubber; wherein, the regenerant comprises 3, 6-dioxa-1, 8-octane dithiol, and the solvent is at least one of toluene and xylene.

Further, in the regenerant addition step, after the heat-retention, methanol is added to the solution for flocculation, and flocs are taken out and dried at 50-70 ℃ for 1-2 days to remove the solvent.

The invention has the beneficial effects that the novel vulcanized rubber reclaimed rubber and the preparation method thereof are provided, sulfur-sulfur bonds in the vulcanized rubber can be selectively broken at low temperature, the consumption is low, the cost is low, and the molecular weight of the reclaimed rubber is high. According to the invention, vulcanized rubber and the regenerant are mixed, and the regenerant permeates into the vulcanized rubber network for decrosslinking through solvent swelling and maintaining the decrosslinking temperature, so that the sulfur-sulfur bond in the waste rubber can be well and selectively broken, and the crosslinked network can not be broken at a relatively low temperature. But also remarkably improves the poor physical and mechanical properties and the sound insulation property of the vulcanized rubber reclaimed rubber.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a flow chart of a method of preparing a vulcanized rubber vulcanizate as described in the examples of the present invention.

Detailed Description

The following detailed description of the preferred embodiments of the present invention is provided to enable those skilled in the art to make and use the present invention in a complete manner, and is provided for illustration of the technical disclosure of the present invention so that the technical disclosure of the present invention will be more clearly understood and appreciated by those skilled in the art how to implement the present invention. The present invention may, however, be embodied in many different forms of embodiment, and the scope of the present invention should not be construed as limited to the embodiment set forth herein, but rather construed as being limited only by the following description of the embodiment.

The invention provides a vulcanized rubber reclaimed rubber, which comprises rubber, a vulcanizing agent, an anti-aging agent and a regenerating agent, wherein the vulcanizing agent comprises sulfur, the anti-aging agent is one or more of N-cyclohexyl-N' -phenyl-p-phenylenediamine, 9-dimethylacridine and 2-mercaptobenzimidazole, and the regenerating agent comprises 3, 6-dioxa-1, 8-octane dithiol.

The regenerant can selectively break sulfur-sulfur bonds in vulcanized rubber at low temperature, the dosage is small, the cost is low, and the molecular weight of the obtained regenerated rubber is high. According to the invention, vulcanized rubber and the regenerant are mixed, and the regenerant permeates into the vulcanized rubber network for decrosslinking through solvent swelling and maintaining the decrosslinking temperature, so that the sulfur-sulfur bond in the waste rubber can be well and selectively broken, and the crosslinked network can not be broken at a relatively low temperature.

In this embodiment, the rubber includes at least one of natural rubber, styrene-butadiene rubber, and isoprene rubber.

In this embodiment, the rubber comprises nitrile rubber or neoprene rubber. The invention adopts the nitrile rubber and the chloroprene rubber as basic materials, the molecular chain of the nitrile rubber has polar side cyano-CN, the molecular chain of the chloroprene rubber contains side group chlorine atom group-Cl, the damping performance is good, and the intermolecular force is strong, so that the sound energy can be converted into heat energy more quickly, and the sound insulation performance is improved.

In this embodiment, the vulcanized rubber reclaimed rubber further includes a carbon black agent, and the carbon black agent is one or more of carbon black N219 and white carbon black. The carbon black agent can improve the mechanical property of the matrix rubber and simultaneously improve the aging resistance and the tearing resistance of the rubber material.

In this embodiment, the vulcanized rubber reclaimed rubber further comprises a catalyst, wherein the catalyst is one or more of tetramethylthiuram disulfide, ethylene thiourea and 2, 2' -dithiodibenzothiazyl. The catalyst can promote the activation of the vulcanizing agent, so that the crosslinking reaction of the vulcanizing agent and rubber molecules is accelerated, and the effects of shortening the vulcanizing time and reducing the vulcanizing temperature are achieved.

In this embodiment, the vulcanized rubber reclaimed rubber further includes an active agent, and the active agent is one or more of stearic acid, zinc oxide, and magnesium oxide. The activator can activate a vulcanization system, improve the crosslinking density of vulcanized rubber and improve the aging resistance of the vulcanized rubber.

In this embodiment, the vulcanized rubber reclaimed rubber further includes a dispersant, and the dispersant includes dioctyl ester. The dispersing agent can improve the dispersion degree of the compounding agent in rubber, shorten the mixing time, improve the production efficiency and simultaneously improve the physical and mechanical properties of the rubber compound.

In this embodiment, the vulcanized rubber reclaimed rubber further includes one or more of mica powder, hollow glass beads or montmorillonite. The mica powder, the hollow glass beads and the montmorillonite are used as fillers, so that the sound insulation performance of the material can be improved.

The invention blends the nitrile rubber and the chloroprene rubber which have better damping performance and larger glass-transition temperature difference, and adds the fillers such as mica powder, hollow glass beads, montmorillonite and the like, thereby obviously improving the sound insulation performance and enhancing the physical and mechanical properties. The maximum sound insulation amount and the average sound insulation amount of the vulcanized rubber reclaimed rubber added with the mica powder, the hollow glass beads and the montmorillonite are improved to a certain extent.

And after the anti-aging agent is added into the vulcanized rubber reclaimed rubber, the oxidation chain scission is reduced, so that the decrosslinking degree of the reclaimed rubber is lower than that of reclaimed rubber without the anti-aging agent. In the embodiment of the invention, the reclaimed rubber obtained by using 3, 6-dioxa-1, 8-octane dithiol as a regenerant has lower crosslinking density and higher decrosslinking degree. In the regeneration process, the decrosslinking degree directly reflects the breaking degree of the crosslinked network in the regeneration reaction, and the lower the crosslinking density after the reaction is, the more obvious the decrosslinking effect is.

The invention also provides a preparation method of the vulcanized rubber reclaimed rubber, which particularly comprises the following steps of S1-S3:

s1, preparing vulcanized rubber, namely adding rubber into the vulcanizing agent to form the vulcanized rubber; the rubber comprises at least one of natural rubber, styrene butadiene rubber, butadiene rubber and isoprene rubber; the vulcanizing agent comprises sulfur;

s2, an anti-aging agent adding step, wherein the anti-aging agent is added into the vulcanized rubber, and is one or more of N-cyclohexyl-N' -phenyl-p-phenylenediamine, 9-dimethylacridine and 2-mercaptobenzimidazole; and

s3, adding a regenerant, namely, placing the vulcanized rubber added with the anti-aging agent in a solvent for full swelling, adding the regenerant, standing to obtain regenerated rubber sol, heating and preserving heat, and removing the solvent to obtain vulcanized rubber regenerated rubber; wherein, the regenerant comprises 3, 6-dioxa-1, 8-octane dithiol, and the solvent is at least one of toluene and xylene.

In this example, in the regenerant addition step S3, after the heat-retention step, methanol was added to the solution to flocculate the solution, and the flocculate was taken out and dried at 50 to 70 ℃ for 1 to 2 days to remove the solvent.

The preparation method provided by the invention has low de-crosslinking reaction temperature, can selectively de-crosslink vulcanized rubber at the temperature of 80-140 ℃, and selectively breaks sulfur-sulfur bonds in the vulcanized rubber; the preparation method provided by the invention has high de-crosslinking degree, effectively improves the de-crosslinking efficiency under corresponding temperature and conditions, and the obtained reclaimed rubber has the highest de-crosslinking degree of 100 percent; the preparation method provided by the invention has good de-crosslinking selectivity, has good de-crosslinking selectivity under corresponding temperature and conditions, and the molecular weight of the obtained reclaimed rubber sol can reach over 65000, preferably 70000-120000, thereby effectively retaining the main chain of the rubber molecule; the regenerant used in the invention has low cost and small dosage, and is suitable for industrial production.

The invention has the beneficial effects that the novel vulcanized rubber reclaimed rubber and the preparation method thereof are provided, sulfur-sulfur bonds in the vulcanized rubber can be selectively broken at low temperature, the consumption is low, the cost is low, and the molecular weight of the reclaimed rubber is high. According to the invention, vulcanized rubber and the regenerant are mixed, and the regenerant permeates into the vulcanized rubber network for decrosslinking through solvent swelling and maintaining the decrosslinking temperature, so that the sulfur-sulfur bond in the waste rubber can be well and selectively broken, and the crosslinked network can not be broken at a relatively low temperature. But also remarkably improves the poor physical and mechanical properties and the sound insulation property of the vulcanized rubber reclaimed rubber.

The vulcanized rubber reclaimed rubber and the preparation method thereof provided by the invention are described in detail above. It should be understood that the exemplary embodiments described herein should be considered merely illustrative for facilitating understanding of the method of the present invention and its core ideas, and not restrictive. Descriptions of features or aspects in each exemplary embodiment should generally be considered as applicable to similar features or aspects in other exemplary embodiments. While the present invention has been described with reference to exemplary embodiments, various changes and modifications may be suggested to one skilled in the art. It is intended that the present invention cover the modifications and variations of this invention provided they come within the spirit and scope of the appended claims and their equivalents and improvements made thereto.