Self-adhesive low-density damping material

Abstract

The invention relates to a self-adhesive low-density damping material. The raw material formula of the self-adhesive low-density damping material comprises the following components in parts by mass: 15-40 parts of butyl rubber; 2-10 parts of ethylene propylene rubber; 10-30 parts of a hollow filler; 5-15 parts of a reinforcing filler; 20 to 50 parts of polyisobutene; 0.1-2 parts of a small molecular auxiliary agent; preferably, the butyl rubber is long-chain branched light cross-linked butyl rubber, and the hollow filler is hollow glass beads. The damping material disclosed by the invention is environment-friendly and convenient to operate, has excellent processability, mechanical property and adhesive property, is free from cold flow and collapse, is lighter due to low density, and can meet the lightweight requirement of shock-absorbing and noise-reducing products.

Description

Technical Field

[0001] The present invention belongs to the technical field of damping materials, and particularly relates to a self-adhesive low-density damping material, a preparation method thereof, and an application thereof. Background Art

[0002] A damping material is a functional material that can absorb vibration mechanical energy and sound energy and may convert them into other forms of energy. Damping materials can be divided into viscoelastic damping materials, high-damping alloy materials, composite damping materials, and intelligent damping materials. Damping materials can be widely used in shock absorption and noise reduction of airplanes, rockets, various aircraft, armored vehicles, tanks, automobiles and other means of transportation, wave absorption and stealth of submarines, environmental protection and other fields. It has excellent sound insulation and shock absorption effects, and can further improve the comfort, safety and lightweight of means of transportation.

[0003] Due to its special viscoelastic properties, rubber has always been the main material for shock absorption and noise reduction. However, a single rubber component material often has poor shock absorption and noise reduction effects due to its low damping factor and narrow damping temperature range, and it is difficult to meet the more stringent application requirements in the engineering field.

[0004] At present, the damping products for sound reduction and noise reduction applied in fields such as automobiles are mainly asphalt-based barrier sheets, PVC-based soft barrier sheets, inorganic-filled sound insulation sheets, and damping coatings. Asphalt-based barrier sheets have good barrier properties, excellent high-temperature performance, and low cost, but the material strength is low, it cannot be formed, has special requirements for construction performance, and is not environmentally friendly. In PVC soft barrier sheets, low-molecular-weight plasticizers are easily precipitated, which will greatly reduce the mechanical properties of the sheets, and this kind of sheet is not easy to recycle, not environmentally friendly, and releases a large amount of harmful hydrogen chloride gas when burned. Inorganic-filled sound insulation sheets are a kind of noise reduction and damping sheets obtained by filling vinyl polymers with inorganic substances. Their sound insulation and noise reduction effects are not prominent, the process flow is relatively complex, and the production equipment is worn greatly. Damping coatings have good damping and sound insulation properties, excellent adhesion, and low cost, and are suitable for various special-shaped surfaces, but require special construction equipment. Summary of the Invention

[0005] Aiming at the problems existing in the prior art, the present invention provides a rubber damping material with excellent operability, high and low temperature resistance, low density, and high damping.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A self-adhesive low-density damping material, the raw material formula of which comprises the following components in parts by mass:

[0008] 15 - 40 parts of butyl rubber; 2 - 10 parts of ethylene - propylene rubber; 10 - 30 parts of hollow filler; 5 - 15 parts of reinforcing filler; 20 - 50 parts of polyisobutylene; 0.1 - 2 parts of small - molecule additive.

[0009] According to an embodiment of the present invention, the raw material formula includes the following components in parts by mass:

[0010] 25 - 35 parts of butyl rubber; 4 - 7 parts of ethylene - propylene rubber; 15 - 25 parts of hollow filler; 5 - 10 parts of reinforcing filler; 30 - 40 parts of polyisobutylene; 0.1 - 1 part of small - molecule additive.

[0011] According to an embodiment of the present invention, the butyl rubber is one or a mixture of long - chain branched slightly cross - linked butyl rubber, star - branched butyl rubber, and halogenated butyl rubber.

[0012] Preferably, the butyl rubber is long - chain branched slightly cross - linked butyl rubber, with a Mooney viscosity [ML(1 + 8)125℃] of 30 - 60 and a branching ratio of 1.0% - 5.0%.

[0013] According to an embodiment of the present invention, the weight percentage content of vinyl in the ethylene - propylene rubber is 40% - 60%, the weight percentage content of the third monomer is 5.0% - 9.0%, and the Mooney viscosity [ML(1 + 4)125℃] is 40 - 60, preferably the Mooney viscosity [ML(1 + 4)125℃] is 40 - 50.

[0014] According to an embodiment of the present invention, the hollow filler is hollow glass microspheres.

[0015] Preferably, the bulk density of the hollow glass microspheres is 0.1 - 0.6 g / cm 3 .

[0016] According to an embodiment of the present invention, the hollow glass microspheres are hollow glass microspheres with a bulk density of 0.1 - 0.15 g / cm 3 of hollow glass microspheres with a bulk density of 0.4 - 0.45 g / cm, or a mixture of the two, with a mass ratio of 1:4 to 4:1, such as 3:1, 2:1.

[0017] According to an embodiment of the present invention, the reinforcing filler is a mixture of one or several of talc, clay, calcium carbonate, carbon black, and white carbon black.

[0018] Preferably, the reinforcing filler is selected from fumed white carbon black (i.e., fumed silica).

[0019] According to an embodiment of the present invention, the number - average molecular weight of the polyisobutylene is 800 - 4000.

[0020] According to an embodiment of the present invention, the polyisobutylene is polyisobutylene with a number average molecular weight of 2500 - 4000, or polyisobutylene with a number average molecular weight of 1000 - 1500, or a mixture of the two, and their mass ratio is 1:3 to 3:1, for example 1:1.

[0021] According to an embodiment of the present invention, when hollow glass microspheres with a lower bulk density are selected, polyisobutylene with a lower molecular weight is selected. Conversely, when hollow glass microspheres with a higher bulk density are selected, polyisobutylene with a higher molecular weight is selected. Thereby, the processability of the damping material can be improved and the filling amount can be ensured.

[0022] According to an embodiment of the present invention, the small molecule additive is one or a mixture of a hindered phenol antioxidant, a hindered amine light stabilizer, and a coupling agent.

[0023] The present invention also provides a preparation method of the above-mentioned self-adhesive low-density damping material, and the method includes the following steps: weighing each component according to the raw material formula of the above-mentioned self-adhesive low-density damping material, and kneading in a kneader to obtain a uniform rubber compound.

[0024] According to an embodiment of the present invention, the preparation method further includes the step of extruding and sheeting the obtained rubber compound to obtain a damping sheet.

[0025] The present invention also provides an application of the above-mentioned self-adhesive low-density damping material, which is used for preparing shock-absorbing and noise-reducing products.

[0026] According to an embodiment of the present invention, the shock-absorbing and noise-reducing products are used in the military, mechanical fields, aerospace industries, construction fields, home appliance industries, etc., such as in the fields of airplanes, rockets, cars, tanks, armored vehicles, etc.

[0027] Beneficial effects

[0028] Compared with asphalt-based barrier sheets, the self-adhesive low-density damping material of the present invention is more environmentally friendly; compared with PVC soft barrier sheets, inorganic-filled sound insulation sheets, and damping coatings, the self-adhesive low-density damping material is more convenient to operate. By selecting appropriate butyl rubber, ethylene-propylene rubber, and polyisobutylene, and controlling the dosage of the three, excellent processing performance, mechanical properties, bonding properties, non-cold flow, and non-collapse properties of the product are ensured. Selecting appropriate hollow fillers can ensure excellent mechanical properties of the product while reducing the product density. The damping material of the present invention is lighter due to its low density and can meet the lightweight requirements of products. Specific embodiments

[0029] The technical solution of the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only for exemplarily illustrating and explaining the present invention, and should not be construed as limiting the protection scope of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention. Unless otherwise specified, the raw materials and reagents used in the following embodiments are commercially available products, or can be prepared by known methods; the operations performed are all known in the art, or are carried out according to the user manuals of commercially available products.

[0030] Example 1. A damping material with self-adhesive low density is made from the following raw materials in parts by weight:

[0031]

[0032] Among them, the butyl rubber is long-chain branched slightly crosslinked butyl rubber, with a Mooney viscosity [ML(1+8)125°C] of 38 and a branching ratio of 2.5%; the vinyl content of the ethylene-propylene rubber is 50%, the ENB content is 9%, and the Mooney viscosity [ML(1+4)125°C] is 50; the hollow glass microspheres are a compound of hollow glass microspheres with a bulk density of 0.12 - 0.13 g / cm 3 and hollow glass microspheres with a bulk density of 0.4 - 0.41 g / cm 3 in a weight ratio of 2:1; the polyisobutylene is a compound of polyisobutylene with a number-average molecular weight of 2700 and polyisobutylene with a number-average molecular weight of 1300 in a weight ratio of 1:1.

[0033] Weigh each component according to the formula of the above damping material with self-adhesive low density, knead in a kneader to obtain a uniform rubber compound; extrude and sheet the obtained rubber compound to obtain the finished product.

[0034] Example 2. A damping material with self-adhesive low density is made from the following raw materials in parts by weight:

[0035]

[0036] Among them, the butyl rubber is long-chain branched slightly crosslinked butyl rubber, with a Mooney viscosity [ML(1+8)125°C] of 35 and a branching ratio of 1.4%; the vinyl content of the ethylene-propylene rubber is 55%, the ENB content is 7.3%, and the Mooney viscosity [ML(1+4)125°C] is 45; the bulk density of the hollow glass microspheres is 0.4 - 0.41 g / cm 3 , and the number-average molecular weight of the polyisobutylene is 2700.

[0037] Weigh each component according to the above formula of the self-adhesive low-density damping material, knead them in a kneader to obtain a uniform rubber compound; extrude and sheet the obtained rubber compound to obtain the finished product.

[0038] Example 3: A damping material with self-adhesive low density is made from the following raw materials in parts by weight:

[0039]

[0040]

[0041] Among them, the butyl rubber is branched slightly cross-linked butyl rubber, with a Mooney viscosity [ML(1+8)125°C] of 60 and a branching ratio of 3.6%; the vinyl content of the ethylene-propylene rubber is 40%, the ENB content is 5.0%, and the Mooney viscosity [ML(1+4)125°C] is 40; the bulk density of the hollow glass microspheres is 0.12 - 0.13 g / cm 3 , and the number-average molecular weight of the polyisobutylene is 950.

[0042] Weigh each component according to the above formula of the self-adhesive low-density damping material, knead them in a kneader to obtain a uniform rubber compound; extrude and sheet the obtained rubber compound to obtain the finished product.

[0043] Comparative Example 1: A damping material with self-adhesive low density is made from the following raw materials in parts by weight:

[0044]

[0045] Among them, the butyl rubber is a conventional non-cross-linked and non-branched butyl rubber, with a Mooney viscosity [ML(1+8)125°C] of 51; the vinyl content of the ethylene-propylene rubber is 40%, the ENB content is 5.0%, and the Mooney viscosity [ML(1+4)125°C] is 40; the bulk density of the hollow glass microspheres is 0.12 - 0.13 g / cm 3 , and the number-average molecular weight of the polyisobutylene is 950.

[0046] Weigh each component according to the above formula of the self-adhesive low-density damping material, knead them in a kneader to obtain a uniform rubber compound; extrude and sheet the obtained rubber compound to obtain the finished product.

[0047] Comparative Example 2: A damping material with self-adhesive low density is made from the following raw materials in parts by weight:

[0048]

[0049] Among them, the butyl rubber is branched slightly cross-linked butyl rubber with a Mooney viscosity [ML(1+8)125℃] of 60 and a branching ratio of 3.6%; the ethylene content of the ethylene-propylene rubber is 40%, the ENB content is 5.0%, and the Mooney viscosity [ML(1+4)125℃] is 40; the mesh number of the expanded perlite is 50-70 mesh, and the number-average molecular weight of the polyisobutylene is 950.

[0050] Weigh each component according to the above formula of the self-adhesive low-density damping material and knead them in a kneader to obtain a uniform rubber compound; extrude and sheet the obtained rubber compound to obtain the finished product.

[0051] Test Example

[0052] Perform performance tests on the self-adhesive low-density damping materials obtained in Examples 1-3 and Comparative Examples 1-2. The results are shown in the following table:

[0053] (1) Density: Refer to GB / T 533-2008 Determination of density of vulcanized rubber: Method A;

[0054] (2) Damping factor: Test using a DMA Q800 type dynamic mechanical property analyzer in the tensile mode;

[0055] (3) High-temperature test: Refer to the requirements of GB / T 2423.2-2008: (85±2)℃, time 168h;

[0056] (4) Low-temperature test: Refer to the requirements of GB / T 2423.1-2008: (-50±2)℃, time 96h;

[0057] (5) Plasticity: Refer to GB / T 12828-2006;

[0058] (6) Peel strength: Refer to ASTM D1000-2017

[0059]

[0060] From the data in the above table, it can be seen that the damping sheets obtained in Examples 1-3 have excellent high and low temperature resistance and mechanical properties, low density, good damping performance, high plasticity, and environmental protection; the damping sheet obtained in Comparative Example 1 shows glue overflow during the high and low temperature tests and poor mechanical properties; during the kneading preparation process of the damping sheet obtained in Comparative Example 2, obvious agglomeration of the filler expanded perlite occurs, resulting in unstable damping performance of the product, and lower mechanical properties and plasticity.

[0061] The above describes the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A self-adhesive low-density damping material, whose raw material formula comprises the following components in parts by mass: 15 - 40 parts of butyl rubber; 2 - 10 parts of ethylene-propylene rubber; 10 - 30 parts of hollow filler; 5 - 15 parts of reinforcing filler; 20 - 50 parts of polyisobutylene; 0.1 - 2 parts of small molecule additive; Preferably, the raw material formula comprises the following components in parts by mass: 25 - 35 parts of butyl rubber; 4 - 7 parts of ethylene-propylene rubber; 15 - 25 parts of hollow filler; 5 - 10 parts of reinforcing filler; 30 - 40 parts of polyisobutylene; 0.1 - 1 part of small molecule additive.

2. The self-adhesive low-density damping material according to claim 1, wherein the butyl rubber is one or a mixture of long-chain branched lightly cross-linked butyl rubber, star-branched butyl rubber, and halogenated butyl rubber.

3. The self-adhesive low-density damping material according to any one of claims 1 - 2, wherein the butyl rubber is long-chain branched lightly cross-linked butyl rubber, with a Mooney viscosity [ML(1 + 8)125°C] of 30 - 60 and a branching ratio of 1.0% - 5.0%; And / or, the weight percentage content of vinyl in the ethylene-propylene rubber is 40% - 60%, the weight percentage content of the third monomer is 5.0% - 9.0%, and the Mooney viscosity [ML(1 + 4)125°C] is 40 - 60, preferably the Mooney viscosity [ML(1 + 4)125°C] is 40 - 50.

4. The self-adhesive low-density damping material according to claim 1, wherein the hollow filler is hollow glass microspheres; preferably, the bulk density of the hollow glass microspheres is 0.1-0.6 g / cm 3 , preferably, the hollow glass microspheres are hollow glass microspheres with a bulk density of 0.1-0.15% g / cm 3 hollow glass microspheres, hollow glass microspheres with a bulk density of 0.4-0.45%, or a mixture of the two, with a mass ratio of 1:4 to 4:1, such as 3:1, 2:

1.

5. The self-adhesive low-density damping material according to claim 1, wherein the reinforcing filler is one or a mixture of talc powder, kaolin, calcium carbonate, carbon black, and white carbon black; Preferably, the reinforcing filler is selected from fumed white carbon black (i.e., fumed silica).

6. The self-adhesive low-density damping material according to claim 1, wherein the number-average molecular weight of the polyisobutylene is 800 - 4000; preferably, the polyisobutylene is polyisobutylene with a number-average molecular weight of 2500 - 4000, or polyisobutylene with a number-average molecular weight of 1000 - 1500, or a mixture of the two, and their mass ratio is 1:3 to 3:1, such as 1:

1.

7. The self-adhesive low-density damping material according to claim 1, wherein the small molecule additive is one or a mixture of hindered phenol antioxidants, hindered amine light stabilizers, and coupling agents.

8. A preparation method of the self-adhesive low-density damping material according to claim 1, the method comprising the following steps: weighing each component according to the raw material formula of the self-adhesive low-density damping material according to claim 1, and kneading in a kneader to obtain a uniform rubber compound.

9. According to the preparation method of claim 8, it further comprises the step of extruding and sheeting the obtained rubber compound to obtain a damping sheet.

10. The application of the self-adhesive low-density damping material according to any one of claims 1 - 7, which is used for preparing shock-absorbing and noise-reducing products.

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