阅读说明：本技术 一种阻尼助剂、由该阻尼助剂制得的高性能橡胶材料及其制备方法 (Damping additive, high-performance rubber material prepared from damping additive and preparation method of high-performance rubber material ) 是由 李斌 张保生 唐军辉 王雪飞 黄良平 杨军 于 2019-11-05 设计创作，主要内容包括：本发明提供了一种阻尼助剂、由该阻尼助剂制得的高性能橡胶材料及其制备方法。该阻尼助剂包括以下重量份的原料：环氧化天然橡胶100份和受阻酚100-300份；环氧化天然橡胶中环氧基团的含量为25％-50％。该阻尼助剂的制备方法包括以下步骤：将环氧化天然橡胶和受阻酚在开炼机上混炼,混炼温度为90-120℃,混炼时间为5-10min,混炼完成后进行下片、冷却,得到所述阻尼助剂。该阻尼助剂分子量大、极性低,从根本上解决阻尼剂易析出的问题。添加该阻尼助剂后制得的橡胶材料,兼具良好的物理机械性能以及阻尼性能,设计理念顺应环保发展要求,长期使用或停放后的性能稳定,可广泛应用于铁路、桥梁、机车、建筑等领域。(The invention provides a damping additive, a high-performance rubber material prepared from the damping additive and a preparation method of the high-performance rubber material. The damping additive comprises the following raw materials in parts by weight: 100 parts of epoxidized natural rubber and 300 parts of hindered phenol; the epoxy group content of the epoxidized natural rubber is 25 to 50 percent. The preparation method of the damping additive comprises the following steps: mixing the epoxidized natural rubber and the hindered phenol on an open mill at the mixing temperature of 90-120 ℃ for 5-10min, and after mixing is finished, blanking and cooling to obtain the damping additive. The damping additive has large molecular weight and low polarity, and fundamentally solves the problem that the damping agent is easy to separate out. The rubber material prepared by adding the damping additive has good physical and mechanical properties and damping properties, the design concept conforms to the requirement of environmental protection development, the performance after long-term use or parking is stable, and the rubber material can be widely applied to the fields of railways, bridges, locomotives, buildings and the like.)

1. The damping additive is characterized by comprising the following raw materials in parts by weight: 100 parts of epoxidized natural rubber and 300 parts of hindered phenol; the epoxy group content of the epoxidized natural rubber is 25 to 50 percent.

2. The damping aid of claim 1, wherein the hindered phenol is at least one of hindered phenol AO-80, hindered phenol AO-60, hindered phenol AO-1024, hindered phenol AO-1076, and hindered phenol AO-1098.

3. The damping aid of claim 1, wherein the epoxidized natural rubber and hindered phenol are present in terms of (mass epoxidized natural rubber/molecular mass epoxidized natural rubber x epoxy degree): (hindered phenol mass/hindered phenol molecular weight) ═ 1: (0.1-0.6), wherein the epoxy group content in the epoxidized natural rubber is 40-50%.

4. The damping aid of claim 1, wherein the epoxidized natural rubber and hindered phenol are present in terms of (mass epoxidized natural rubber/molecular mass epoxidized natural rubber x epoxy degree): (hindered phenol mass/hindered phenol molecular weight) ═ 1: (0.6-1.5), wherein the epoxy group content in the epoxidized natural rubber is 25% -40%.

5. A method for preparing the damping aid according to any one of claims 1 to 4, comprising the steps of:

mixing the epoxidized natural rubber and the hindered phenol on an open mill at the mixing temperature of 90-120 ℃ for 5-10min, and after mixing is finished, blanking and cooling to obtain the damping additive.

6. The high-performance rubber material is characterized by comprising the following raw materials in parts by weight:

60-80 parts of natural rubber,

5-30 parts of damping additive,

1-5 parts of vulcanizing agent,

2-6 parts of anti-aging agent,

4-6 parts of zinc oxide,

1-3 parts of stearic acid,

30-60 parts of carbon black,

5-20 parts of naphthenic oil,

1-2.5 parts of an accelerator.

7. The high performance rubber material of claim 6, wherein the antioxidant is 2,2, 4-trimethyl-1, 2-dihydroquinoline polymer and/or N- (1,3 dimethylbutyl) -N' -phenyl-p-phenylenediamine; the vulcanizing agent is sulfur; the accelerator is N-cyclohexyl-2-benzothiazole sulfonamide.

8. A method for preparing the high-performance rubber material according to claim 6 or 7, characterized by comprising the following steps:

(1) putting natural rubber, a damping auxiliary agent, an anti-aging agent, zinc oxide, stearic acid, carbon black and naphthenic oil into an internal mixer, mixing, and discharging and cooling after mixing to obtain master batch;

(2) and (3) putting the master batch into an open rubber mixing mill, adding a vulcanizing agent and an accelerator for mixing, standing, vulcanizing, and obtaining the high-performance rubber material after vulcanization.

9. The method as claimed in claim 8, wherein in the step (1), the mixing temperature is 110-120 ℃ and the mixing time is 8-12 min.

10. The preparation method according to claim 8, wherein in the step (2), the mixing temperature is 15-30 ℃, the mixing time is 4-6min, the mixture is left for more than 24h and then vulcanized, the vulcanization temperature is 150 ℃, and the vulcanization time is 15-20 min.

Technical Field

The invention belongs to the technical field of high polymer materials, and particularly relates to a damping additive, a high-performance rubber material prepared from the damping additive and a preparation method of the high-performance rubber material.

Background

With the development of modern science and technology and the continuous improvement of human living standard, people put forward higher requirements on the comfort of working and living environments, so that how to effectively treat various kinds of vibration and noise pollution becomes one of important subjects concerned by scientists. The polymer material has good damping effect due to the unique viscoelastic property, and is widely applied to the fields of rail transit, construction, machinery and the like. How to prepare a high-damping rubber material with high physical and mechanical properties and strong long-term service performance stability is an important problem which is concerned by rubber formula designers.

At present, the methods for improving the damping performance of rubber materials mainly comprise the following steps: firstly, rubber with excellent damping performance is adopted as main body rubber, such as butyl rubber, polynorbornene rubber and the like; secondly, hindered phenol damping agents are adopted, hydrogen bonds can be formed between molecules and in molecules of the damping agents, and chain breakage and secondary recombination are generated under the external action of the hydrogen bonds, so that the damping performance of the rubber material is improved; and thirdly, a resin tackifying technology is adopted, and the resin is utilized to increase the viscosity of the rubber material, so that the effect of improving the damping effect is achieved. Although the above methods can improve the damping performance of the rubber material to a certain extent, they all have some disadvantages, which limit their wide application in high damping rubber materials: 1. rubber with excellent damping performance is adopted as main body rubber, such as butyl rubber, polynorbornene rubber and the like, and the prepared rubber material has excellent damping performance, but is only suitable for rubber products with low performance requirements and high added value due to high price and poor physical and mechanical properties (tensile strength, elongation at break and the like); 2. hindered phenol damping agents are adopted, hindered phenol is a micromolecular and high-polarity substance, the polarity difference between the polarity and the polarity of a general rubber material is large, if nonpolar rubber (NR, SBR and the like) is used as main body rubber, the prepared high-damping rubber product is easy to separate out in the using process, and the damping performance change of the high-damping material is large after long-term use; if polar rubber (NBR) is adopted as main body rubber, the designed high-damping rubber material has lower mechanical property; if nonpolar rubber and polar rubber are used together (NR/NBR and the like), the physical and mechanical properties of the rubber material are reduced due to large polarity difference between the nonpolar rubber and the polar rubber, and meanwhile, the polarity difference between the nonpolar rubber and hindered phenol is large, so that the designed rubber product can not ensure that the hindered phenol is not separated out in the long-term use process, and the prepared rubber product still has the problem of large change of damping property in long-term use; 3. the resin is a non-environment-friendly material, so that along with the enhancement of environmental awareness of people, national environmental laws and regulations are sound, the use of the resin in the future is bound to be further limited. Therefore, the traditional process for preparing the high-damping rubber material has the problems that the physical mechanical property and the damping property are difficult to reconcile, and the whole stable structure of the matrix is not considered, so that the designed high-damping rubber material has large change of the damping property after long-term use, and even loses the damping property in the long-term use process.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome at least one of the defects and shortcomings mentioned in the background art, and provide a damping additive, a high-performance rubber material prepared from the damping additive and a preparation method thereof.

In order to solve the technical problems, the technical scheme provided by the invention is as follows:

a damping auxiliary agent comprises the following raw materials in parts by weight: 100 parts of epoxidized natural rubber and 300 parts of hindered phenol; the epoxy group content of the epoxidized natural rubber is 25 to 50 percent.

The damping additive of the invention has to control the adding proportion of the epoxidized natural rubber and the hindered phenol and the content of the epoxy group in the epoxidized natural rubber within the range of the invention, so that the epoxidized natural rubber and the hindered phenol can be ensured to fully generate the grafting reaction, and the hindered phenol is prevented from being filled in the rubber material, thereby preventing the hindered phenol from being separated out after the rubber product is used for a long time.

The damping assistant preferably contains a hydroxyl group in the hindered phenol, and the hindered phenol is at least one of hindered phenol AO-80, hindered phenol AO-60, hindered phenol AO-1024, hindered phenol AO-1076, and hindered phenol AO-1098. More preferably, the hindered phenol is hindered phenol AO-80 and/or hindered phenol AO-60.

The damping aid, preferably, the epoxidized natural rubber and the hindered phenol are mixed in the following ratio (mass of epoxidized natural rubber/molecular mass of epoxidized natural rubber x epoxy degree): (hindered phenol mass/hindered phenol molecular weight) ═ 1: (0.1-0.6), wherein the epoxy group content in the epoxidized natural rubber is 40-50%. The damping additive is prepared by controlling the proportion of the epoxidized natural rubber and the hindered phenol and the content of the epoxy group in the epoxidized natural rubber within the range, and then the prepared damping additive is added into the rubber material, so that the high-tensile-strength high-damping rubber material can be obtained.

The damping aid, preferably, the epoxidized natural rubber and the hindered phenol are mixed in the following ratio (mass of epoxidized natural rubber/molecular mass of epoxidized natural rubber x epoxy degree): (hindered phenol mass/hindered phenol molecular weight) ═ 1: (0.6-1.5), wherein the epoxy group content in the epoxidized natural rubber is 25% -40%. The damping additive is prepared by controlling the proportion of the epoxidized natural rubber and the hindered phenol and the content of the epoxy group in the epoxidized natural rubber within the range, and then the prepared damping additive is added into the rubber material, so that the rubber material with high elongation at break and high damping can be obtained.

As a general inventive concept, the present invention also provides a preparation method of the damping aid, comprising the steps of:

mixing the epoxidized natural rubber and the hindered phenol on an open mill at the mixing temperature of 90-120 ℃ for 5-10min, and after mixing is finished, blanking and cooling to obtain the damping additive.

According to the preparation method of the damping additive, the mixing temperature and the mixing time are controlled within the range of the invention, so that the epoxy group in the epoxidized natural rubber and the hydroxyl group in the hindered phenol can be subjected to grafting reaction fully, and the novel damping additive with large molecular weight and low polarity is prepared, so that the problem that the damping agent is easy to precipitate is fundamentally solved, and the stability of the performance of a rubber product in the long-term use or standing process is ensured. If the mixing temperature and the mixing time are lower than the range of the invention, the grafting reaction cannot occur, and if the mixing temperature and the mixing time are beyond the range of the invention, the ENR molecular chain is broken, the molecular weight of the prepared damping additive is reduced, and the precipitation phenomenon still occurs when the damping additive is used in rubber materials.

According to the preparation method of the damping additive, an epoxy group in epoxidized natural rubber and a hydroxyl group in hindered phenol are subjected to ring-opening reaction, and the hindered phenol is grafted on a molecular chain of the epoxidized natural rubber to form the novel damping additive with high molecular weight and low polarity; the damping additive can be directly added into a natural rubber formula without being limited by the hardness range in a basic formula, can keep good physical machinery while greatly improving the damping characteristic of a rubber material, can improve the damping performance of the rubber material when added into a non-natural rubber formula, and basically keeps the physical mechanical performance unchanged, so that the rubber material has certain universality. Taking the hindered phenol AO-80 as an example, the mechanism of the grafting reaction between the epoxidized natural rubber and the hindered phenol is shown as the formula (1):

as a general inventive concept, the invention also provides a high-performance rubber material, which comprises the following raw materials in parts by weight in order to ensure the comprehensive performance and the service performance of the rubber material:

60-80 parts of natural rubber,

5-30 parts of damping additive,

1-5 parts of vulcanizing agent,

2-6 parts of anti-aging agent,

4-6 parts of zinc oxide,

1-3 parts of stearic acid,

30-60 parts of carbon black,

5-20 parts of naphthenic oil,

1-2.5 parts of an accelerator.

The above high-performance rubber material is preferably, in order to improve the overall performance of the rubber material, the antioxidant is 2,2, 4-trimethyl-1, 2-dihydroquinoline polymer (antioxidant RD) and/or N- (1,3 dimethylbutyl) -N' -phenyl-p-phenylenediamine (antioxidant 6 PPD); the vulcanizing agent is sulfur; the accelerator is N-cyclohexyl-2-benzothiazole sulfonamide (accelerator CZ).

As a general inventive concept, the present invention also provides a method for preparing the high performance rubber material as described above, comprising the steps of:

(1) putting natural rubber, a damping auxiliary agent, an anti-aging agent, zinc oxide, stearic acid, carbon black and naphthenic oil into an internal mixer, mixing, and discharging and cooling after mixing to obtain master batch;

(2) and (3) putting the master batch into an open rubber mixing mill, adding a vulcanizing agent and an accelerator for mixing, then vulcanizing, and obtaining the high-performance rubber material after the vulcanization is finished.

In the preparation method, preferably, in the step (1), the mixing temperature is 110-120 ℃, and the mixing time is 8-12 min. The mixing parameters in the step (1) need to be controlled within the range of the invention, if the mixing parameters are lower than the range of the invention, the mixing is not uniform, the material performance fluctuation is large, and if the mixing parameters exceed the range of the invention, the molecular chain is broken, and the physical and mechanical properties of the rubber material are influenced.

In the preparation method, preferably, in the step (2), the mixing temperature is 15-30 ℃ and the mixing time is 4-6 min. The mixing parameters in the step (2) need to be controlled within the range of the invention, if the mixing parameters are lower than the range of the invention, the mixing is not uniform, the material performance fluctuation is large, and if the mixing parameters exceed the range of the invention, the molecular chain is broken, the rubber material is burnt, and the physical and mechanical properties of the rubber material are influenced.

In the preparation method, preferably, in the step (2), in order to promote the rubber auxiliary agent to be uniformly dispersed in the rubber compound, the rubber compound is placed for more than 24 hours and then vulcanized, wherein the vulcanization temperature is 150 ℃ and the vulcanization time is 15-20 min. The vulcanization parameters in the step (2) need to be controlled within the range of the invention, vulcanization temperature or vulcanization time lower than the vulcanization temperature or vulcanization time of the invention can result in under-vulcanization of rubber products, and vulcanization temperature or vulcanization time higher than the vulcanization temperature or vulcanization time of the invention can result in excessive crosslinking of vulcanization bonds in rubber, and mechanical properties are greatly reduced.

Compared with the prior art, the invention has the advantages that:

(1) according to the invention, micromolecule hindered phenol is grafted on a macromolecule epoxidized natural rubber molecular chain through an in-situ grafting technology to prepare the damping auxiliary agent with characteristics of macromolecule chain and low polarity, the prepared damping auxiliary agent has strong universality, has good compatibility with polar main rubber or non-polar main rubber, and simultaneously has larger molecular weight, and when the damping auxiliary agent is added into a rubber formula, the problem that the damping auxiliary agent is easy to separate out due to large polarity difference with the main rubber can be effectively solved, and the designed rubber material is ensured to have long-term use stability.

(2) The rubber material prepared by adding the damping additive has good physical and mechanical properties and damping properties, all environmental protection indexes meet the requirements of vehicles in European Union and China on toxic and harmful indexes in the rubber material, the design concept conforms to the environmental protection development requirement, the performance after long-term use or parking is stable, and the rubber material can be widely applied to the fields of railways, bridges, locomotives, buildings and the like.

(3) The preparation method of the invention has the advantages of short process flow, simple operation, environmental protection and low process cost, and is suitable for industrial production.

Drawings

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

FIG. 1 is a photograph after aging of the rubber material obtained in example 1 of the present invention;

FIG. 2 is a photograph after aging of the rubber material obtained in example 2 of the present invention;

FIG. 3 is a photograph after aging of the rubber material obtained in example 3 of the present invention;

FIG. 4 is a photograph after aging of the rubber material obtained in comparative example 1 of the present invention;

FIG. 5 is a photograph after aging of the rubber material obtained in comparative example 2 of the present invention.

Detailed Description

In order to facilitate an understanding of the invention, the invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of the invention is not limited to the specific embodiments below.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.