A high-damping EPDM rubber composite material and its preparation method

Abstract

This invention discloses a high-damping EPDM rubber composite material and its preparation method. The technical solution adopted in this invention is as follows: First, excess functionalized liquid rubber and graphene oxide are uniformly mixed in a solvent. The carboxyl and amino groups in the liquid rubber react chemically with the oxygen-containing functional groups such as hydroxyl groups on the surface of the graphene oxide to prepare liquid rubber-modified graphene oxide. The modified graphene oxide is then composited with EPDM rubber, and hindered phenol, crosslinking agent, antioxidant, and plasticizer are added simultaneously. After high-temperature vulcanization, the liquid rubber-modified graphene oxide / hindered phenol / EPDM rubber composite material is obtained. The small molecules of liquid rubber, the graphene oxide filler network, and the hydrogen bonding between graphene oxide and hindered phenol synergistically improve the damping performance of the EPDM composite material.

Description

Technical Field

[0001] This invention belongs to the field of rubber nanocomposite technology, and relates to a high-damping EPDM rubber composite material and its preparation method. Background Technology

[0002] Due to the high saturation of its molecular backbone, ethylene propylene diene monomer (EPDM) rubber possesses excellent properties such as resistance to heat, oxygen, ozone, and ultraviolet radiation, and is often used in outdoor rubber products.

[0003] High-damping spacer rubber is mainly used in high-voltage transmission lines, primarily to prevent whiplash between conductors and suppress aerobatic vibrations and secondary span oscillations. Damping spacers offer better vibration damping performance than rigid spacers. Currently, damping spacers mainly operate outdoors, exposed to sunlight, ultraviolet radiation, and humidity, hence EPDM rubber is chosen as the matrix rubber for damping spacers. However, compared to butyl rubber and some polar rubbers, EPDM rubber has a more flexible molecular chain, lacks polar groups, and has no crystallinity. Therefore, EPDM rubber itself has relatively poor damping performance, often requiring the addition of other damping systems to the matrix to achieve high damping performance.

[0004] Currently, graphene oxide, as a sheet-like filler, is frequently used in rubber materials for reinforcement. Simultaneously, graphene oxide sheets readily generate internal friction during dynamic deformation, consuming energy and providing a certain damping effect. However, graphene oxide / rubber composites prepared by traditional methods exhibit poor dispersibility and compatibility between graphene oxide and the rubber matrix, resulting in limited damping effects. Liquid rubber, due to its smaller molecular chains, possesses strong mobility and can effectively dissipate external energy through its viscosity during dynamic deformation, achieving a high damping effect. Therefore, modifying graphene oxide with functionalized liquid rubber can both prevent graphene aggregation and enhance the compatibility between graphene oxide and rubber, while also increasing the damping properties of the composite material.

[0005] Furthermore, hindered phenols are also commonly used alone in damping rubbers due to their strong intermolecular interactions. In addition, the hindered phenol structure contains a large number of -OH groups, which can form hydrogen bonds with the oxygen-containing functional groups on the surface of graphene oxide. This dynamic hydrogen bonding interaction can also consume energy and increase damping during dynamic deformation. Summary of the Invention

[0006] The purpose of this invention is to provide a method for preparing a high-damping liquid rubber modified graphene oxide / hindered phenol / EPDM rubber composite material. The main method involves constructing a damping system among end-functionalized modified liquid rubber, graphene oxide, and hindered phenol in an EPDM rubber matrix, which is used to address the problem of poor damping performance in EPDM rubber.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a method for preparing a high-damping liquid rubber modified graphene oxide / hindered phenol / ethylene propylene diene monomer (EPDM) rubber composite material, comprising:

[0008] Step 1: Take an excess of end-functionalized liquid rubber and graphene oxide and stir and disperse them thoroughly in a solvent. React at 40-100℃ for 0.5-2 hours. After the reaction is complete, remove the solvent molecules to obtain liquid rubber modified graphene oxide.

[0009] Step 2: Mix the liquid rubber modified graphene oxide, EPDM rubber, nanofiller, hindered phenol, antioxidant and plasticizer evenly in a mixing device, and further add crosslinking agent and / or co-crosslinking agent to obtain a uniformly dispersed compound.

[0010] Step 3: The compound is further vulcanized at a high temperature of 140-200°C in a mold. During the high-temperature vulcanization reaction, the liquid rubber modified graphene oxide and the hindered phenol crosslink at high temperature to form dynamic damping bonds, thereby obtaining a high-damping liquid rubber modified graphene oxide / hindered phenol / EPDM rubber composite material.

[0011] The introduction of liquid rubber not only prevents the aggregation of graphene oxide, but also increases the compatibility between graphene oxide and EPDM rubber.

[0012] This invention modifies graphene oxide using functionalized liquid rubber, which on the one hand prevents graphene oxide aggregation, and on the other hand improves the compatibility between graphene oxide and EPDM rubber. Furthermore, hindered phenols are introduced into the composite material. During high-temperature vulcanization, weak hydrogen bonds are formed between the phenolic groups of the hindered phenols and the oxygen-containing functional groups on the surface of graphene oxide. During dynamic deformation, these hydrogen bonds continuously break and rebuild, playing a role in consuming energy and damping the deformation.

[0013] Furthermore, in step one, the liquid rubber is a liquid rubber with end groups of epoxy, carboxyl, or amino, specifically one or a mixture of epoxidized liquid natural rubber, carboxyl liquid styrene-butadiene rubber, carboxyl liquid nitrile rubber, carboxyl liquid polybutadiene rubber, amino liquid silicone rubber, and epoxidized liquid butyl rubber.

[0014] Furthermore, in step one, the molar ratio of the liquid rubber to the terminal functional groups of graphene oxide is 5:1 to 1:1.

[0015] Furthermore, in step one, the solvent is one or a mixture of toluene, xylene, chlorobenzene, tetrahydrofuran, and dimethyl sulfoxide.

[0016] Furthermore, in step two, the nanofiller is one or more of carbon black, silicon dioxide, kaolin, calcium carbonate, and clay.

[0017] Furthermore, in step two, the hindered phenol is one or more of AO-60, AO-80, AO-1035, and AO2246, or a mixture thereof.

[0018] Furthermore, in step two, the plasticizer is one of paraffin oil, naphthenic oil, or aromatic oil.

[0019] Further, in step two, the antioxidant is one or a mixture of N-phenyl-2-naphthylamine (antioxidant D), 2,2,4-trimethyl-1,2-dihydroquinoline polymer (antioxidant RD), N-cyclohexyl-N'-phenyl-p-phenylenediamine (antioxidant 4010), N-isopropyl-N'-phenyl-p-phenylenediamine (antioxidant 4010NA), and N-(1,3-dimethyl)butyl-N'-phenyl-p-phenylenediamine (antioxidant 4020).

[0020] Furthermore, in step two, the mixing equipment is one or more combinations of an open mill, a kneader, and an internal mixer.

[0021] Further, in step two, the crosslinking agent is one or a mixture of sulfur, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, bis(2,4-dichlorobenzoyl)peroxide, dicumyl peroxide, and di-tert-butylperoxide; the co-crosslinking agent is one or a mixture of N-cyclohexyl-2-benzothiazole sulfenamide (CZ), triallyl isocyanurate, and N,N′-m-phenylenebismaleimide.

[0022] Further, in step two, the weight proportions of each component are as follows: 100 parts of EPDM rubber, 1-20 parts of liquid rubber modified graphene oxide, 20-120 parts of nanofiller, 1-30 parts of hindered phenol, 0.2-5 parts of crosslinking agent, 0.1-5 parts of co-crosslinking agent, 0.5-4 parts of antioxidant, and 5-30 parts of plasticizer.

[0023] The beneficial effects of this invention are as follows: This invention constructs a triple damping system in EPDM rubber by using liquid rubber to modify graphene oxide and introducing a hindered phenol system into the system: (1) liquid rubber small molecule system; (2) graphene oxide filler system; (3) hindered phenol system; the above three systems work together to effectively consume energy in the dynamic deformation process, thereby improving the damping performance of EPDM rubber. Detailed Implementation

[0024] The present invention will be further described below with reference to specific embodiments. However, the present invention is not limited to the following embodiments.

[0025] Example 1

[0026] (1) Take epoxidized liquid natural rubber and graphene oxide (molar ratio of terminal functional groups 2:1) and stir and disperse them in toluene. React at 60°C for 2 hours. After the reaction is complete, remove the toluene to obtain graphene oxide modified with epoxidized liquid natural rubber.

[0027] (2) Mix 100 parts of EPDM rubber, 5 parts of graphene oxide modified with epoxidized liquid natural rubber, 50 parts of silica, 10 parts of hindered phenol AO80, 2 parts of antioxidant 4010NA, and 5 parts of paraffin oil in a mixer until uniformly mixed. Then add 2 parts of peroxide dicumyl peroxide and 1 part of crosslinking agent triallyl isocyanurate to obtain a uniformly dispersed compound.

[0028] (3) The compound is vulcanized at 160°C. In the high vulcanization reaction, the graphene oxide modified by the epoxidized liquid natural rubber and the hindered phenol AO-80 form dynamic damping bonds during the crosslinking process at high temperature, resulting in a high-damping epoxidized liquid natural rubber modified graphene oxide / hindered phenol / EPDM rubber composite material.

[0029] Comparative Example 1

[0030] (1) Mix 100 parts of EPDM rubber, 5 parts of graphene oxide, 50 parts of silica, 2 parts of 4010NA and 5 parts of paraffin oil in a mixer until uniform. Then add 2 parts of dicumyl peroxide and 1 part of crosslinking agent triallyl isocyanurate to obtain a uniformly dispersed compound.

[0031] (2) The compound rubber was vulcanized at 160°C to obtain a EPDM rubber composite material reinforced with graphene oxide and silica.

[0032] Example 2

[0033] (1) Take carboxyl liquid styrene-butadiene rubber and graphene oxide (molar ratio of terminal functional groups 1.5:1) and stir and disperse them in xylene. React at 60℃ for 2h. After the reaction is complete, remove xylene to obtain graphene oxide modified with carboxyl liquid styrene-butadiene rubber.

[0034] (2) Mix 100 parts of EPDM rubber, 8 parts of carboxyl liquid styrene-butadiene rubber modified graphene oxide, 60 parts of carbon black, 10 parts of hindered phenol AO-60, 2 parts of 4010NA, and 10 parts of aromatic oil in a mixer until uniformly mixed. Then add 2 parts of sulfur and 1 part of crosslinking agent CZ to obtain a uniformly dispersed compound.

[0035] (3) The compound is vulcanized at 150°C. In the high vulcanization reaction, the graphene oxide modified by carboxyl liquid styrene-butadiene rubber and the hindered phenol AO-60 form dynamic damping bonds during the crosslinking process at high temperature, resulting in a high-damping carboxyl liquid styrene-butadiene rubber modified graphene oxide / hindered phenol / EPDM rubber composite material.

[0036] Example 3

[0037] (1) Take carboxyl liquid nitrile rubber and graphene oxide (molar ratio of terminal functional groups 3:1) and stir and disperse them in toluene. React at 80℃ for 3h. After the reaction is complete, remove the toluene to obtain graphene oxide modified with carboxyl liquid nitrile rubber.

[0038] (2) Mix 100 parts of EPDM rubber, 15 parts of carboxylated liquid nitrile rubber modified graphene oxide, 30 parts of silica, 30 parts of kaolin, 20 parts of hindered phenol AO-1035, 2 parts of antioxidant RD, and 10 parts of paraffin oil in a mixer until uniformly mixed. Then add 2 parts of peroxide 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane to obtain a uniformly dispersed compound.

[0039] (3) The compound was vulcanized at 165°C. During the high-temperature vulcanization reaction, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane-modified graphene oxide and hindered phenol AO-1035 formed dynamic damping bonds during the crosslinking process at high temperature, resulting in a highly damped 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane-modified graphene oxide / hindered phenol / EPDM rubber composite material.

[0040] Example 4

[0041] (1) Take carboxylated polybutadiene rubber and graphene oxide (molar ratio of terminal functional groups 5:1) and stir and disperse them in chlorobenzene. React at 70°C for 5 hours. After the reaction is complete, remove the chlorobenzene to obtain graphene oxide modified with carboxylated polybutadiene rubber.

[0042] (2) Mix 100 parts of EPDM rubber, 5 parts of carboxylated polybutadiene rubber modified graphene oxide, 50 parts of calcium carbonate, 10 parts of hindered phenol AO2246, 2 parts of antioxidant D, and 5 parts of paraffin oil in a mixer until uniformly mixed. Then add 3 parts of peroxide bis(2,4-dichlorobenzoyl) and 1 part of crosslinking agent N,N′-m-phenylenebismaleimide to obtain a uniformly dispersed compound.

[0043] (3) The compound was vulcanized at 165°C. During the high-temperature vulcanization reaction, N,N′-m-phenylenebismaleimide-modified graphene oxide and hindered phenol AO-2246 formed dynamic damping bonds during the crosslinking process at high temperature, resulting in a high-damping carboxyl polybutadiene rubber-modified graphene oxide / hindered phenol / EPDM rubber composite material.

[0044] Example 5

[0045] (1) Take epoxidized liquid butyl rubber and graphene oxide (molar ratio of terminal functional groups 3.5:1) and stir and disperse them in chlorobenzene. React at 75°C for 3 hours. After the reaction is complete, remove the chlorobenzene to obtain graphene oxide modified with epoxidized liquid butyl rubber.

[0046] (2) Mix 100 parts of EPDM rubber, 5 parts of graphene oxide modified with epoxidized liquid butyl rubber, 30 parts of carbon black, 30 parts of clay, 30 parts of hindered phenol AO80, 4 parts of antioxidant 4010NA, and 10 parts of paraffin oil in a mixer until uniformly mixed. Then add 2 parts of di-tert-butyl peroxide isopropylbenzene and 1.5 parts of triallyl isocyanurate to obtain a uniformly dispersed compound.

[0047] (3) The compound is vulcanized at 180°C. In the high vulcanization reaction, the graphene oxide modified by epoxidized butyl rubber and the hindered phenol AO-80 form dynamic damping bonds during the crosslinking process at high temperature, resulting in a high-damping epoxidized liquid butyl rubber modified graphene oxide / hindered phenol / EPDM rubber composite material.

[0048] The damping performance test results of the functionalized liquid rubber modified graphene oxide / hindered phenol / ethylene propylene diene monomer (EPDM) rubber composites prepared in Comparative Examples 1 and Examples 1-5 are as follows:

[0049]

[0050] The above embodiments have described the specific implementation process of the present invention in detail. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent substitutions, and these equivalent variations or substitutions all fall within the scope of protection claimed in this application.

Claims

1. A method for preparing a high-damping EPDM rubber composite material, characterized in that, include: Step 1: Take an excess of end-functionalized liquid rubber and graphene oxide and stir and disperse them thoroughly in a solvent, and react at 40-100℃ for 0.5-2h; after the reaction is complete, remove the solvent to obtain liquid rubber modified graphene oxide; the molar ratio of the end functional groups of the liquid rubber to graphene oxide is 5:1~1:

1. Step 2: Liquid rubber modified graphene oxide, EPDM rubber, nanofiller, hindered phenol, antioxidant, and plasticizer are mixed evenly in a mixing device, and a crosslinking agent and / or co-crosslinking agent are further added to obtain a uniformly dispersed compound; the hindered phenol is one or a mixture of AO-60, AO-80, AO-1035, and AO2246. Step 3: The compound rubber is vulcanized at a high temperature of 140~200℃ in a mold. During the high-temperature vulcanization reaction, the liquid rubber modified graphene oxide and the hindered phenol crosslink at high temperature to form dynamic damping bonds, thereby obtaining a high-damping liquid rubber modified graphene oxide / hindered phenol / EPDM rubber composite material.

2. The preparation method according to claim 1, characterized in that, In step one, the liquid rubber is a liquid rubber with epoxy, carboxyl, or amino end groups, and is one or a mixture of epoxidized liquid natural rubber, carboxyl liquid styrene-butadiene rubber, carboxyl liquid nitrile rubber, carboxyl polybutadiene rubber, amino liquid silicone rubber, and epoxidized liquid butyl rubber.

3. The preparation method according to claim 1, characterized in that, In step one, the solvent is one or a mixture of toluene, xylene, chlorobenzene, tetrahydrofuran, and dimethyl sulfoxide.

4. The preparation method according to claim 1, characterized in that, In step two, the nanofiller is one or more of carbon black, silicon dioxide, kaolin, calcium carbonate, and clay.

5. The preparation method according to claim 1, characterized in that, In step two, the mixing equipment is one or more combinations of an open mill, a kneader, and an internal mixer.

6. The preparation method according to claim 1, characterized in that, In step two, the crosslinking agent is one or a mixture of sulfur, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, bis(2,4-dichlorobenzoyl peroxide), dicumyl peroxide, and di-tert-butylperoxyisopropylbenzene; the co-crosslinking agent is one or a mixture of triallyl isocyanurate and N,N′-m-phenylenebismaleimide.

7. The preparation method according to claim 1, characterized in that, In step two, the weight proportions of each component are as follows: 100 parts of EPDM rubber, 1-20 parts of liquid rubber modified graphene oxide, 20-120 parts of nanofiller, 1-30 parts of hindered phenol, 0.2-5 parts of crosslinking agent, 0.1-5 parts of co-crosslinking agent, 0.5-4 parts of antioxidant, and 5-30 parts of plasticizer.

8. A high-damping EPDM rubber composite material, characterized in that, It is prepared using the preparation method described in any one of claims 1-7.

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