Damping rubber composite material as well as preparation method and application thereof

Abstract

The invention relates to a damping rubber composite material as well as a preparation method and application thereof. The damping rubber composite material is prepared from the following raw materials in parts by weight: 45 to 60 parts of butyl rubber, 40 to 55 parts of regenerated rubber, 10 to 20 parts of ethylene-vinyl acetate copolymer, 6 to 10 parts of low molecular weight amorphous alpha-olefin copolymer, 10 to 20 parts of inorganic filler and 2.5 to 4 parts of vulcanizing agent. The damping rubber composite material disclosed by the invention takes butyl rubber and regenerated rubber as main materials, has relatively high recycled materials, and is economical and environment-friendly; meanwhile, through compounding of the ethylene-vinyl acetate copolymer and the low-molecular-weight amorphous alpha-olefin copolymer, the compatibility and the vulcanization rate of the butyl rubber and the regenerated rubber are well improved, so that the obtained damping rubber composite material has good damping performance, the vulcanization speed is high, and the compression permanent deformation is small.

Description

Technical Field

[0001] The invention relates to the technical field of rubber materials, and in particular to a damping rubber composite material and a preparation method and application thereof. Background Art

[0002] Due to its unique wide glass transition, butyl rubber (Isobutylene Isoprene Rubber, IIR) has good damping performance in a wide temperature range. Its vulcanized rubber not only has good air tightness, but also has good aging resistance to heat, ozone and chemicals. It is often used to prepare damping and shock absorbing layer structures or sealing structures. Butyl recycled rubber (Recycled Isobutylene Isoprene Rubber, RIIR) is a kind of waste rubber. It can have certain raw rubber properties after a series of desulfurization processing steps. Replacing part of IIR in the formula with RIIR not only has certain environmental value, but also can reduce costs. The prior art often blends IIR with RIIR to prepare damping materials. However, RIIR still has certain compounding agents after the regeneration process, and the molecular weight is greatly reduced compared with IIR raw rubber. The viscosity, molecular weight, and cross-linking degree of IIR raw rubber are quite different. There is still a certain difficulty in blending the two. When preparing thin products such as the rubber edge of a speaker, it is very easy to deform and the permanent deformation is high.

[0003] CN102606414B discloses a wind turbine blade including a damping and vibration reduction structural layer and a manufacturing method thereof, wherein the damping and vibration reduction material layer is composed of the following raw materials in parts by weight: 5-20 parts of butyl rubber, 10-50 parts of recycled butyl rubber, 5-20 parts of epoxy resin, 20-60 parts of fly ash, 5-10 parts of paraffin oil, 2-10 parts of terpene resin, and 0.5-1 part of antioxidant. The invention uses butyl rubber and recycled butyl rubber as raw materials to prepare a high damping and vibration reduction structural layer in the generator blade, thereby effectively improving the blade's resistance to strong wind impact, reducing the amplitude of harmful vibrations, improving aerodynamic efficiency, reducing vibration noise, and extending service life. However, the resin vulcanization system used in its formula has a slow vulcanization rate and low production efficiency. In addition, the formula has a low rubber content, and the elasticity and compression permanent deformation of the rubber are large. It can be used as a damping layer for wind turbine blades, but it cannot be used in a horn fold under a stable frequency amplitude, and the use scenario is limited.

[0004] Therefore, it is of great significance to design and provide an economical, environmentally friendly, high-damping, easy-to-mold rubber composite material with a fast vulcanization speed and small compression permanent set. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a damping rubber composite material and its preparation method and application. The damping rubber composite material is prepared by compounding butyl rubber and recycled rubber as raw materials, which has a high recycling rate and is economical and environmentally friendly; at the same time, the compatibility and vulcanization rate of butyl rubber and recycled rubber are well improved by compounding ethylene-vinyl acetate copolymer and low molecular weight amorphous α-olefin copolymer, so that the obtained damping rubber composite material has good damping performance, fast vulcanization speed and small compression permanent deformation.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a damping rubber composite material, wherein the raw materials for preparing the damping rubber composite material include the following components in parts by weight:

[0008]

[0009] The present invention uses butyl rubber and recycled rubber as main materials, which is not only cost-saving and environmentally friendly, but also can well improve the vulcanization rate, thereby improving production efficiency. Ethylene-vinyl acetate copolymer (EVA) and low molecular weight amorphous alpha-olefin copolymer (APAO) are both random copolymers. Among them, EVA has changed its original crystal state due to the introduction of short branches formed by polar acetate groups in the ethylene chain, making EVA more flexible and elastic. Because of its high glass transition temperature (higher than conventional rubber), it can greatly improve the damping performance of the composite material after blending with rubber; APAO is a low molecular weight, high fluidity, amorphous, and highly random flexible olefin copolymer obtained by polymerization using alpha-olefin as raw material, which can greatly improve processing performance. And because they are all amorphous olefin copolymers, they have good compatibility with EVA. The combination of the two can well improve the compatibility and vulcanization rate of butyl rubber and recycled rubber, so that the damping rubber composite material has good damping performance, fast vulcanization speed and small compression permanent deformation. The inorganic filler is a reinforcing agent, which ensures that the damping rubber composite material has good mechanical properties; the use of the vulcanizing agent can not only increase the vulcanization rate, thereby improving production efficiency, but also can further reduce the permanent deformation of the damping rubber composite material.

[0010] In the present invention, the content of butyl rubber is 45-60 parts by weight, for example, it can be 45 parts by weight, 48 parts by weight, 50 parts by weight, 52 parts by weight, 55 parts by weight, 58 parts by weight or 60 parts by weight.

[0011] In the present invention, the butyl rubber is further preferably a halogenated butyl rubber, which has better compatibility with other components and a faster vulcanization rate, and can be quickly co-vulcanized with the regenerated IIR containing various compounding agents under a sulfur vulcanization system.

[0012] The content of the recycled rubber is 40-55 parts by weight, for example, it can be 40 parts by weight, 42 parts by weight, 45 parts by weight, 48 parts by weight, 50 parts by weight, 52 parts by weight or 55 parts by weight.

[0013] In the present invention, when the mass ratio of butyl rubber to recycled rubber is (0.8-1.5):1, the obtained damping rubber composite material has good mechanical properties, small compression permanent deformation and high vulcanization rate. When the mass ratio of the two is lower than 0.8:1, that is, the butyl rubber content is too low, the vulcanization rate is increased, but the mechanical properties are reduced and the compression permanent deformation is large; when the mass ratio of the two is higher than 1.5:1, that is, the butyl rubber content is too high, the vulcanization rate is low and the proportion of recycled materials is low, thereby resulting in low production efficiency, high cost and poor practicality.

[0014] The content of ethylene-vinyl acetate copolymer is 10-20 parts by weight, for example, it can be 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight, 15 parts by weight, 16 parts by weight, 17 parts by weight, 18 parts by weight or 19 parts by weight.

[0015] EVA (Tg is 20-60℃) has good compatibility with IIR and RIIR. When blended with IIR and RIIR, it can move the damping range of IIR toward high temperature, increase the glass transition temperature and maximum loss factor, and greatly improve the damping performance of the resulting damping rubber composite at room temperature. When its content is too low, the mechanical properties and damping improvement effects are not good; when its content is too high, the rubber content and recycled material content of the composite material are reduced, the degree of vulcanization is reduced, and the risk of permanent deformation increases.

[0016] The content of the low molecular weight amorphous α-olefin copolymer is 6-10 parts by weight, for example, 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight or 10 parts by weight.

[0017] APAO has a small molecular weight and low Mooney viscosity. As a compatibilizer, it has good interfacial compatibility with butyl rubber and recycled butyl rubber, which can improve the processing performance of the blending system, build a "bridge" for the compatibility of IIR and RIIR with a large difference in viscosity, and improve the compatibility and cross-linking density between the blending raw materials, thereby improving its co-vulcanization and reducing the permanent deformation of the resulting damping rubber composite material.

[0018] The content of the inorganic filler is 10-20 parts by weight, for example, it can be 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight, 15 parts by weight, 16 parts by weight, 17 parts by weight, 18 parts by weight or 19 parts by weight.

[0019] The content of the vulcanizing agent is 2.5-4 parts by weight, for example, 2.8 parts by weight, 3 parts by weight, 3.2 parts by weight, 3.5 parts by weight, 3.8 parts by weight or 4 parts by weight.

[0020] Preferably, the mass ratio of the ethylene-vinyl acetate copolymer to the low molecular weight amorphous α-olefin copolymer is (1.5-2.5):1, wherein (1.5-2.5) can be, for example, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4 or 2.5, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0021] The use of EVA and APAO in the present invention can play a synergistic role, so as to obtain a damping rubber composite material with fast vulcanization rate, small compression permanent deformation and good damping performance. Further, when the mass ratio of the two is (1.5-2.5): 1, its technical effect is better, when the mass ratio of the two is lower than 1.5: 1, the content of EVA is low, although EVA and APAO have good compatibility at this time, but because APAO is a low molecular weight polymer, the overall polar group (acetic acid) ratio of the system is small, and flexibility, strength, and damping performance are all undesirable, so that the damping performance and mechanical properties of the damping rubber material obtained are reduced, and the compression permanent deformation and vulcanization time are increased; when the mass ratio of the two is higher than 2.5: 1, the content of EVA is high, the proportion of small molecule non-polar substances in the system is small, and low temperature resistance and fluidity are poor, which is limited for the improvement of rubber compatibility and processability, so that the damping performance of the damping rubber material obtained is poor, the compression permanent deformation is large, and the vulcanization efficiency is low.

[0022] Preferably, the regenerated rubber comprises regenerated butyl rubber and / or regenerated butyl rubber powder, preferably a combination of regenerated butyl rubber and regenerated butyl rubber powder.

[0023] Preferably, the content of the recycled butyl rubber is 35-45 parts by weight, for example, it can be 35 parts by weight, 36 parts by weight, 37 parts by weight, 38 parts by weight, 39 parts by weight, 40 parts by weight, 41 parts by weight, 42 parts by weight, 43 parts by weight, 44 parts by weight or 45 parts by weight, etc.

[0024] Preferably, the content of the recycled butyl rubber powder is 5-10 parts by weight, for example, 5 parts by weight, 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight or 10 parts by weight.

[0025] The regenerated rubber in the present invention is a combination of regenerated butyl rubber and regenerated butyl rubber powder, which has good dispersion effect and high utilization rate of the regenerated rubber. The regenerated butyl rubber and the regenerated butyl rubber powder are both derived from waste inner tubes of scrap trucks, pickup trucks and other automobiles. The desulfurization process is a normal pressure twin-screw continuous desulfurization. The process energy consumption of regenerated rubber production is 800-830kw·h / t, which is much lower than the process energy consumption of synthetic IIR rubber (>2000kw·h / t); in addition, the mixing and vulcanization time of the regenerated rubber composite rubber is greatly shortened, which can further reduce the energy consumption in the processing process. The recyclable material of the final product in the present invention accounts for no less than 30%, which effectively improves its practical performance.

[0026] Preferably, the vulcanizing agent includes a main vulcanizing agent and an auxiliary vulcanizing agent.

[0027] Preferably, the content of the main vulcanizing agent is 1.9-2.5 parts by weight, for example, 1.9 parts by weight, 2 parts by weight, 2.1 parts by weight, 2.2 parts by weight, 2.3 parts by weight, 2.4 parts by weight or 2.5 parts by weight.

[0028] Preferably, the primary vulcanizing agent comprises sulfur and / or a peroxide vulcanizing agent, preferably a combination of sulfur and a peroxide vulcanizing agent.

[0029] Preferably, the content of sulfur is 0.3-0.5 parts by weight, for example, it can be 0.3 parts by weight, 0.32 parts by weight, 0.35 parts by weight, 0.38 parts by weight, 0.4 parts by weight, 0.42 parts by weight, 0.45 parts by weight, 0.48 parts by weight or 0.5 parts by weight.

[0030] Preferably, the content of the peroxide vulcanizing agent is 1.6-2.0 parts by weight, for example, it can be 1.6 parts by weight, 1.65 parts by weight, 1.7 parts by weight, 1.75 parts by weight, 1.8 parts by weight, 1.85 parts by weight, 1.9 parts by weight, 1.95 parts by weight or 2 parts by weight, etc.

[0031] Preferably, the mass ratio of the peroxide vulcanizing agent to sulfur is (3.5-5):1, wherein (3.5-5) can be, for example, 3.5, 3.8, 4, 4.2, 4.4, 4.6, 4.8 or 5, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0032] The present invention adopts the vulcanization system of sulfur / peroxide vulcanizer and can be rapidly vulcanized and molded, with good moldability, no mucosa, deformation and other phenomena. The use of peroxide vulcanizer can effectively improve the vulcanization rate and reduce permanent deformation, and the addition of sulfur can be conducive to the demoulding of the obtained damping rubber composite material; further, when the mass ratio of peroxide vulcanizer to sulfur is (3.5-5): 1, its technical effect is better. When the mass ratio of the two is lower than 3.5: 1, the peroxide ratio is small, the vulcanization rate and the degree of vulcanization are both low, and the permanent deformation is higher; when the mass ratio of the two is higher than 5: 1, the peroxide ratio is higher, and the decomposition product of the peroxide vulcanizer at high temperature will not only cause demoulding difficulties, but also contain certain irritating odors, so that the production environment and production efficiency are reduced.

[0033] Preferably, the peroxide curing agent includes any one of dicumyl peroxide, di-tert-butyl peroxide or 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, or a combination of at least two thereof.

[0034] Preferably, the content of the co-vulcanizing agent is 0.6-1.5 parts by weight, for example, it can be 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight, 0.9 parts by weight, 1 part by weight, 1.1 parts by weight, 1.2 parts by weight, 1.3 parts by weight, 1.4 parts by weight or 1.5 parts by weight, etc.

[0035] Preferably, the co-vulcanizing agent includes any one of triallyl cyanurate, triallyl isocyanurate or 1,2-polybutadiene, or a combination of at least two thereof.

[0036] Preferably, the inorganic filler comprises carbon black.

[0037] Preferably, the raw materials for preparing the damping rubber composite material further include any one of a release agent, an antioxidant or a deodorant, or a combination of at least two thereof.

[0038] Preferably, the content of the release agent is 0.5-2 parts by weight, for example, 0.5 parts by weight, 0.8 parts by weight, 1 part by weight, 1.2 parts by weight, 1.4 parts by weight, 1.6 parts by weight, 1.8 parts by weight or 2 parts by weight.

[0039] Preferably, the release agent is an internal release agent.

[0040] Preferably, the internal mold release agent comprises zinc stearate and / or calcium stearate, preferably a combination of zinc stearate and calcium stearate.

[0041] Preferably, the mass ratio of zinc stearate to calcium stearate is (1-3):1, wherein (1-3) can be, for example, 1, 1.2, 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.6, 2.8 or 3, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0042] The invention adds a specific internal mold release agent into the raw materials for preparing the damping rubber composite material to reduce the adhesion of the rubber formed in the mold to the mold cavity wall, facilitates demoulding, and improves the quality rate and labor production efficiency.

[0043] Preferably, the content of the antioxidant is 1-3 parts by weight, for example, it can be 1 part by weight, 1.2 parts by weight, 1.4 parts by weight, 1.6 parts by weight, 1.8 parts by weight, 2 parts by weight, 2.2 parts by weight, 2.4 parts by weight, 2.6 parts by weight, 2.8 parts by weight or 3 parts by weight, etc.

[0044] Preferably, the antioxidant includes antioxidant 4020 and / or antioxidant RD, preferably a combination of antioxidant 4020 and antioxidant RD.

[0045] Preferably, the mass ratio of the antioxidant 4020 to the antioxidant RD is (1-2):1, (1-2) can be, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or 2, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0046] The invention adds a specific antioxidant into the raw materials for preparing the damping rubber composite material to improve the anti-aging performance thereof.

[0047] Preferably, the content of the deodorant is 1-2 parts by weight, for example, it can be 1 part by weight, 1.1 parts by weight, 1.2 parts by weight, 1.3 parts by weight, 1.4 parts by weight, 1.5 parts by weight, 1.6 parts by weight, 1.7 parts by weight, 1.8 parts by weight, 1.9 parts by weight or 2 parts by weight, etc.

[0048] Preferably, the deodorant comprises hydroquinone and / or salicylic acid, preferably a combination of hydroquinone and salicylic acid.

[0049] Preferably, the mass ratio of hydroquinone to salicylic acid is (1-2):1, (1-2) can be, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or 2, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0050] The present invention adds a specific deodorant to the raw materials for preparing the damping rubber composite material to reduce the odor of the reclaimed rubber. The principle is mainly to achieve the deodorizing effect by allowing the volatile sulfide in the reclaimed rubber to react with it to generate non-volatile substances.

[0051] Preferably, the thickness of the damping rubber composite material is 0.2-2 mm, for example, it can be 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm or 2 mm, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0052] In a second aspect, the present invention provides a method for preparing the damping rubber composite material as described in the first aspect, the preparation method comprising the following steps:

[0053] The raw materials including butyl rubber, recycled rubber, ethylene-vinyl acetate copolymer, low molecular weight amorphous α-olefin copolymer and inorganic filler are blended in one stage, and after cooling, a vulcanizing agent is added to carry out low-temperature mixing, open milling and vulcanization molding to obtain the damping rubber composite material.

[0054] Preferably, the one-stage blending is carried out under stirring, and the stirring speed is 30-50r / min, for example, it can be 30r / min, 35r / min, 35r / min, 38r / min, 40r / min, 42r / min, 45r / min, 48r / min or 50r / min, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0055] Preferably, the temperature of the blending stage is 120-140°C, for example, it can be 120°C, 122°C, 125°C, 128°C, 130°C, 132°C, 135°C, 138°C or 140°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0056] Preferably, the blending time is 7-10 min.

[0057] Preferably, the cooling method is rapid cooling with cold water.

[0058] Preferably, the cooling temperature is 35-45°C, for example, it can be 35°C, 36°C, 38°C, 40°C, 42°C or 45°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0059] Preferably, the low-temperature mixing is carried out under stirring, and the stirring speed is 30-50r / min, for example, it can be 30r / min, 35r / min, 35r / min, 38r / min, 40r / min, 42r / min, 45r / min, 48r / min or 50r / min, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0060] Preferably, the low-temperature mixing temperature is 35-45°C, for example, it can be 35°C, 36°C, 38°C, 40°C, 42°C or 45°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0061] Preferably, the low-temperature mixing time is 3-5 min, for example, it can be 3 min, 3.2 min, 3.5 min, 3.8 min, 4 min, 4.2 min, 4.5 min, 4.8 min or 5 min, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0062] Preferably, the refining of the lower sheet includes refining and triangle bagging.

[0063] Preferably, the refining includes refining with left and right cutting knives.

[0064] Preferably, the number of refining is 3-5 times (for example, 3 times, 4 times or 5 times).

[0065] Preferably, the triangulation includes 0.5 mm for 5-8 times (for example, 5 times, 6 times, 7 times or 8 times).

[0066] Preferably, the roller spacing in the open milling is 4 mm.

[0067] Preferably, the vulcanization molding temperature is 180-200°C, for example, it can be 180°C, 182°C, 185°C, 188°C, 190°C, 192°C, 195°C, 198°C or 200°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0068] Exemplarily, the preparation method of the damping rubber composite material provided by the present invention specifically comprises the following steps:

[0069] (1) One-stage blending: Put butyl rubber, reclaimed rubber and EVA into an internal mixer, add APAO, inorganic filler, internal mold release agent, antioxidant and deodorant, stir at 120-140°C and 30-50r / min for 7-10 minutes to obtain a mixed mixture.

[0070] (2) Low-temperature mixing: The mixed mixture obtained in step (1) is passed through cold water to quickly cool to 35-45°C, a vulcanizing agent is added, and the mixture is stirred at 30-50 r / min for 3-5 minutes to obtain a banburying mixture.

[0071] (3) Open refining and sheeting. The internally kneaded mixture obtained in step (3) is refined on an open refining mill with left and right cutters for 3-5 times each, and triangular packages of 0.5 mm are made for 5-8 times. The roller distance is adjusted to 4 mm to produce a film.

[0072] (4) Vulcanization molding: The film obtained in step (3) is vulcanized at 180-200° C. to obtain the damping rubber composite material.

[0073] In a third aspect, the present invention provides a use of the damping rubber composite material as described in the first aspect in a speaker.

[0074] Compared with the prior art, the present invention has at least the following beneficial effects:

[0075] (1) The damping rubber composite material provided by the present invention reduces the use of IIR raw rubber by using recycled IIR rubber and recycled IIR rubber powder, which can greatly save costs and reduce environmental pollution; by selecting EVA and APAO with good compatibility with IIR and RIIR components for compounding, the compatibility and vulcanization rate of butyl rubber and recycled rubber can be well improved, so that the obtained damping rubber composite material has good damping performance, fast vulcanization speed, and small compression permanent deformation. Furthermore, its production process is simple, suitable for large-scale production, and is conducive to promoting its application.

[0076] (2) The damping rubber composite material provided by the present invention has a high content of recycled materials, good damping performance, small compression permanent deformation, high vulcanization rate, and is easy to form, and can be well applied to the production and use of speakers; its vulcanization rate is 70-90s, the effective damping temperature range is greater than 50°C, the compression permanent deformation is not higher than 15.2%, and the recycled material content is greater than 30%. DETAILED DESCRIPTION

[0077] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0078] Unless otherwise specified, the raw materials used in the following examples and comparative examples are all commercially available. Information on some of the raw materials is as follows:

[0079] Butyl rubber, 2211, 2244, 2255 purchased from ExxonMobil;

[0080] Recycled butyl rubber and recycled butyl rubber powder were purchased from Jiangsu Zhonghong Environmental Protection Technology Company, ZH-RIIR-40A, ZH-RIIR-45A, and ZH-RIIR-50A;

[0081] Ethylene-vinyl acetate copolymer (EVA), Elvax210W, Elvax240W, and Elvax250 purchased from DuPont, USA;

[0082] Low molecular weight amorphous α-olefin copolymer (APAO), RT2715, RT2730, RT2780 purchased from REXtac, USA;

[0083] The internal mold release agent is zinc stearate and calcium stearate in a mass ratio of 3:1;

[0084] The antioxidants are antioxidant 4020 and antioxidant RD in a mass ratio of 2:1;

[0085] The deodorant is hydroquinone and salicylic acid in a mass ratio of 1:1.

[0086] Example 1

[0087] This embodiment provides a damping rubber composite material, and the raw materials for preparing the damping rubber composite material include the following components in parts by weight:

[0088]

[0089] The butyl rubber is brominated butyl rubber 2211, with a bromine content of about 2.1wt% and a Mooney viscosity of 32; the recycled butyl rubber and recycled butyl rubber powder are both ZH-RIIR-40A; the EVA is Elvax210W, with a vinyl acetate weight percentage of 28%, a melt flow rate of 400g / 10min, and a glass transition temperature of 60°C; the APAO is RT2715, with an average molecular weight of 4500.

[0090] The preparation method of the damping rubber composite material comprises the following steps:

[0091] (1) One-stage blending: Put butyl rubber, recycled butyl rubber, recycled butyl rubber powder and EVA into an internal mixer, add APAO, carbon black N550, internal mold release agent, antioxidant and deodorant, stir at 120°C and 30 r / min for 10 minutes to obtain a mixed mixture.

[0092] (2) Low-temperature mixing: The mixed mixture obtained in step (1) was quickly cooled to 35° C. by passing cold water, sulfur, DCP and TAIC were added, and stirred at 30 r / min for 5 min to obtain a banburying mixture.

[0093] (3) Open milling. The internally kneaded mixture obtained in step (3) is turned over by left and right cutters on an open mill for 3 times each, and triangularly packaged 5 times with a thickness of 0.5 mm. The roller distance is adjusted to 4 mm to produce a film.

[0094] (4) Vulcanization molding: The film obtained in step (3) is vulcanized at 180° C. to obtain the damping rubber composite material.

[0095] Example 2

[0096] This embodiment provides a damping rubber composite material, and the raw materials for preparing the damping rubber composite material include the following components in parts by weight:

[0097]

[0098]

[0099] The butyl rubber is brominated butyl rubber 2244, with a bromine content of about 1.2wt% and a Mooney viscosity of 46; the recycled butyl rubber and recycled butyl rubber powder are both ZH-RIIR-45A; the EVA is Elvax240W, with a vinyl acetate weight percentage of 28%, a melt flow rate of 43g / 10min, and a glass transition temperature of 60°C; the APAO is RT2730 from REXtac of the United States, with an average molecular weight of 5300.

[0100] The preparation method of the damping rubber composite material comprises the following steps:

[0101] (1) One-stage blending: Put butyl rubber, recycled butyl rubber, recycled butyl rubber powder and EVA into an internal mixer, add APAO, carbon black N550, internal mold release agent, antioxidant and deodorant, stir at 130°C and 40 r / min for 8 minutes to obtain a mixed mixture.

[0102] (2) Low-temperature mixing: The mixed mixture obtained in step (1) was quickly cooled to 40° C. by passing cold water, sulfur, DCP and TAIC were added, and the mixture was stirred at 40 r / min for 4 min to obtain a banburying mixture.

[0103] (3) Open milling. The internally kneaded mixture obtained in step (3) is refining on an open mill with left and right cutters for 4 times each, and triangularly packaged with 0.5 mm for 6 times. The roller distance is adjusted to 4 mm to produce a film.

[0104] (4) Vulcanization molding: The film obtained in step (3) is vulcanized at 190° C. to obtain the damping rubber composite material.

[0105] Example 3

[0106] This embodiment provides a damping rubber composite material, and the raw materials for preparing the damping rubber composite material include the following components in parts by weight:

[0107]

[0108]

[0109] The butyl rubber is brominated butyl rubber 2255, with a bromine content of about 2.0wt% and a Mooney viscosity of 46; the recycled butyl rubber and recycled butyl rubber powder are both ZH-RIIR-50A; the EVA is Elvax250W, with a vinyl acetate weight percentage of 28%, a melt flow rate of 25g / 10min, and a glass transition temperature of 60°C; the APAO is RT2780 from REXtac of the United States, with an average molecular weight of 6400.

[0110] The preparation method of the damping rubber composite material comprises the following steps:

[0111] (1) One-stage blending: Put butyl rubber, recycled butyl rubber, recycled butyl rubber powder and EVA into an internal mixer, add APAO, carbon black N550, internal mold release agent, antioxidant and deodorant, stir at 140°C and 50 r / min for 7 minutes to obtain a mixed mixture.

[0112] (2) Low-temperature mixing: The mixed mixture obtained in step (1) was cooled to 45°C by passing cold water, sulfur, DCP and TAIC were added, and the mixture was stirred at 50 r / min for 3 min to obtain a banburying mixture.

[0113] (3) Open milling. The internally kneaded mixture obtained in step (3) is turned over by left and right cutters on an open mill for 5 times each, and triangularly packaged 8 times with a thickness of 0.5 mm. The roller distance is adjusted to 4 mm to produce a film.

[0114] (4) Vulcanization molding: The film obtained in step (3) is vulcanized at 200° C. to obtain the damping rubber composite material.

[0115] Example 4

[0116] This embodiment provides a damping rubber composite material, which differs from Example 2 in that the weight of APAO is adjusted from 8 weight parts to 9 weight parts, and the weight of EVA is adjusted from 15 weight parts to 14 weight parts, and other raw material components, contents and preparation methods are the same as those in Example 2.

[0117] Example 5

[0118] This embodiment provides a damping rubber composite material, which differs from Example 2 in that the weight of APAO is adjusted from 8 weight parts to 6.5 weight parts, and the weight of EVA is adjusted from 15 weight parts to 16.5 weight parts, and other raw material components, contents and preparation methods are the same as those in Example 2.

[0119] Comparative Example 1

[0120] This comparative example provides a damping rubber composite material, which differs from Example 2 in that no recycled nitrile rubber and recycled nitrile rubber powder are added, the content of butyl rubber is adjusted from 50 parts by weight to 100 parts by weight, and other raw material components, contents and preparation methods are the same as those in Example 2.

[0121] Comparative Example 2

[0122] This comparative example provides a damping rubber composite material, which differs from Example 2 in that APAO is not added, and its reduced weight portion is allocated to EVA, and other raw material components, contents and preparation methods are the same as those in Example 2.

[0123] Comparative Example 3

[0124] This comparative example provides a damping rubber composite material, which differs from Example 2 in that EVA is not added, and the reduced weight portion thereof is allocated to APAO, and other raw material components, contents and preparation methods are the same as those in Example 2.

[0125] Comparative Example 4

[0126] This comparative example provides a damping rubber composite material, which differs from Example 2 in that the content of EVA is adjusted from 15 parts by weight to 5 parts by weight, and other raw material components, contents and preparation methods are the same as those in Example 2.

[0127] Comparative Example 5

[0128] This comparative example provides a damping rubber composite material, which differs from Example 2 in that the content of EVA is adjusted from 15 parts by weight to 25 parts by weight, and other raw material components, contents and preparation methods are the same as those in Example 2.

[0129] Comparative Example 6

[0130] This comparative example provides a damping rubber composite material, which differs from Example 2 in that the weight of APAO is adjusted from 8 weight parts to 11.5 weight parts, and the weight of EVA is adjusted from 15 weight parts to 11.5 weight parts, and the other raw material components, contents and preparation methods are the same as those in Example 2.

[0131] Comparative Example 7

[0132] This comparative example provides a damping rubber composite material, which differs from Example 2 in that the weight of APAO is adjusted from 8 weight parts to 5.5 weight parts, and the weight of EVA is adjusted from 15 weight parts to 17.5 weight parts, and other raw material components, contents and preparation methods are the same as those in Example 2.

[0133] Comparative Example 8

[0134] This comparative example provides a damping rubber composite material, which differs from Example 2 in that the weight of butyl rubber is adjusted from 50 parts by weight to 40 parts by weight, and the weight of recycled rubber is adjusted from 50 parts by weight to 60 parts by weight (48 parts by weight of recycled butyl rubber + 12 parts by weight of recycled butyl rubber powder), and other raw material components, contents and preparation methods are the same as those in Example 2.

[0135] Comparative Example 9

[0136] This comparative example provides a damping rubber composite material, which differs from Example 2 in that the weight of butyl rubber is adjusted from 50 parts by weight to 65 parts by weight, and the weight of recycled rubber is adjusted from 50 parts by weight to 35 parts by weight (28 parts by weight of recycled butyl rubber + 7 parts by weight of recycled butyl rubber powder), and other raw material components, contents and preparation methods are the same as those in Example 2.

[0137] Comparative Example 10

[0138] This comparative example provides a damping rubber composite material, which differs from Example 2 in that the weight portion of sulfur is adjusted from 0.4 weight portion to 0.55 weight portion, and the weight portion of DCP is adjusted from 1.8 weight portions to 1.65 weight portions, and other raw material components, contents and preparation methods are the same as those in Example 2.

[0139] The damping rubber composite materials in Examples 1-5 and Comparative Examples 1-10 were subjected to performance tests, and the test methods / standards are as follows:

[0140] (1) Loss factor tanδ: measured using a dynamic mechanical analyzer (DMA) with a frequency set to 10 Hz;

[0141] (2) Tensile strength / elongation at break: tested according to the method specified in the national standard GB / T528-2009;

[0142] (3) Compression set test: The test was conducted in accordance with the method specified in GB / T7759.1-2015. The test medium was hot air, the temperature was 70°C, the test time was 3 days, and the initial compression rate of the compression set was 15%.

[0143] The test results are shown in Table 1.

[0144] Table 1

[0145]

[0146]

[0147] The test results show that:

[0148] (1) It can be seen from Examples 1 to 5 that the present invention can achieve the technical effects of improving mechanical, damping and other properties, shortening the vulcanization time, and reducing permanent deformation by introducing EVA and APAO into the IIR / recycled IIR system. The proportion of recyclable materials in the obtained damping rubber composite material is not less than 30%, the effective damping temperature range is greater than 50°C, the compression permanent deformation is not higher than 15.2%, and the vulcanization time t 90 Below 90s.

[0149] (2) By comparing Example 2 with Example 4, Example 5, and Comparative Example 6 and Comparative Example 7, it can be seen that the mass ratio of EVA to APAO in Example 2, Example 4 and Example 5 is (1.5-2.5):1, and the damping rubber composite materials obtained therefrom all have the characteristics of excellent damping performance, small compression permanent deformation and fast vulcanization time. However, in Comparative Example 6, the mass ratio of EVA to APAO is 1:1, and the mechanical properties such as tensile strength and elongation at break of the damping rubber composite material obtained therefrom are significantly reduced, and the compression permanent deformation increases, the vulcanization time is significantly increased, and the effective damping temperature range is less than 50°C; in Comparative Example 7, the mass ratio of EVA to APAO is 3:1, and the low-temperature resistance and flow properties of the damping rubber composite material obtained therefrom deteriorate, the damping performance is poor, and the compression permanent deformation significantly increases. This shows that the present invention can effectively improve the damping performance of the damping rubber composite material obtained, reduce the compression permanent deformation, and improve the vulcanization efficiency by optimizing the mass ratio of EVA to APAO.

[0150] (3) By comparing Example 2 with Comparative Example 1, it can be seen that in Comparative Example 1, no recycled rubber is added, and its vulcanization time is long and the vulcanization rate is significantly reduced, indicating that the combined use of butyl rubber and recycled rubber in the present invention not only reduces the use of IIR raw rubber, greatly saves costs, reduces environmental pollution, but also can effectively improve production efficiency, which is beneficial to improving its practical performance.

[0151] (4) By comparing Example 2 with Comparative Examples 2 and 3, it can be seen that the combined use of EVA and APAO in the present invention can play a synergistic role, thereby obtaining a damping rubber composite material with a fast vulcanization rate, a small compression deformation and good damping performance. When any one of them is missing, the effective damping temperature range and mechanical properties of the damping rubber composite material obtained are significantly reduced, and the compression permanent deformation is increased and the vulcanization rate is reduced.

[0152] (5) By comparing Example 2 with Comparative Examples 4 and 5, it can be seen that the EVA content in Comparative Example 4 is too low, the effective damping temperature range of the damping rubber composite material obtained is narrowed, and the tensile strength and elongation at break are reduced, that is, the improvement effect of its mechanical properties and damping properties is not good; the EVA content in Comparative Example 5 is too high, the proportion of recycled materials in the damping rubber composite material obtained is reduced, the vulcanization time is long, and the compression permanent deformation is increased, indicating that the present invention can make the obtained damping rubber composite material have excellent damping properties on the basis of maintaining good mechanical properties through the specific selection of EVA content, and the vulcanization rate is high and the permanent deformation is small.

[0153] (6) By comparing Example 2 with Comparative Examples 8 and 9, it can be seen that the content of recycled rubber in Comparative Example 8 is too high, and the compression permanent set of the damping rubber composite material obtained is large and the mechanical properties are reduced. The content of butyl rubber in Comparative Example 9 is too high, and the proportion of recycled materials in the damping rubber composite material obtained is low and the vulcanization rate is reduced. This shows that the present invention can make the obtained damping rubber composite material have a higher proportion of recycled materials, better mechanical properties, high vulcanization rate and small compression permanent set by further optimizing the mass ratio of butyl rubber and recycled rubber, thereby effectively improving its production efficiency, reducing production costs, and having strong practicality.

[0154] (7) By comparing Example 2 with Comparative Example 10, it can be seen that the mass ratio of the peroxide vulcanizer to sulfur in Comparative Example 10 is lower than 3.5:1, and the resulting damping rubber composite material has a lower vulcanization rate and a higher permanent deformation.

[0155] In summary, the present invention adds a certain proportion of EVA and APAO and a specific vulcanizing agent to the IIR / regenerated IIR system, so that the obtained damping rubber composite material can have excellent damping performance, faster vulcanization rate, lower compression permanent set and other technical effects while ensuring good mechanical properties.

[0156] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A damping rubber composite material, characterized in that: The raw materials for preparing the damping rubber composite material include the following components in parts by weight:

2. The damping rubber composite material according to claim 1, characterized in that: The mass ratio of the ethylene-vinyl acetate copolymer to the low molecular weight amorphous α-olefin copolymer is (1.5-2.5):

1.

3. The damping rubber composite material according to claim 1 or 2, characterized in that: The regenerated rubber comprises regenerated butyl rubber and / or regenerated butyl rubber powder, preferably a combination of regenerated butyl rubber and regenerated butyl rubber powder; Preferably, the content of the regenerated butyl rubber is 35-45 parts by weight; Preferably, the content of the recycled butyl rubber powder is 5-10 parts by weight.

4. The damping rubber composite material according to any one of claims 1 to 3, characterized in that: The vulcanizing agent includes a main vulcanizing agent and an auxiliary vulcanizing agent; Preferably, the content of the main vulcanizing agent is 1.9-2.5 parts by weight; Preferably, the primary vulcanizing agent comprises sulfur and / or a peroxide vulcanizing agent, preferably a combination of sulfur and a peroxide vulcanizing agent; Preferably, the content of sulfur is 0.3-0.5 parts by weight; Preferably, the content of the peroxide curing agent is 1.6-2.0 parts by weight; Preferably, the mass ratio of the peroxide vulcanizing agent to sulfur is (3.5-5):1; Preferably, the peroxide curing agent includes any one or a combination of at least two of dicumyl peroxide, di-tert-butyl peroxide or 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane; Preferably, the content of the co-vulcanizing agent is 0.6-1.5 parts by weight; Preferably, the co-vulcanizing agent includes any one of triallyl cyanurate, triallyl isocyanurate or 1,2-polybutadiene, or a combination of at least two thereof.

5. The damping rubber composite material according to any one of claims 1 to 4, characterized in that: The inorganic filler includes carbon black.

6. The damping rubber composite material according to any one of claims 1 to 5, characterized in that: The raw materials for preparing the damping rubber composite material further include any one of a release agent, an antioxidant or a deodorant, or a combination of at least two thereof; Preferably, the content of the release agent is 0.5-2 parts by weight; Preferably, the release agent is an internal release agent; Preferably, the internal mold release agent comprises zinc stearate and / or calcium stearate, preferably a combination of zinc stearate and calcium stearate; Preferably, the mass ratio of zinc stearate to calcium stearate is (1-3):1; Preferably, the content of the antioxidant is 1-3 parts by weight; Preferably, the antioxidant includes antioxidant 4020 and / or antioxidant RD, preferably a combination of antioxidant 4020 and antioxidant RD; Preferably, the mass ratio of the antioxidant 4020 to the antioxidant RD is (1-2):1; Preferably, the content of the deodorant is 1-2 parts by weight; Preferably, the deodorant comprises hydroquinone and / or salicylic acid, preferably a combination of hydroquinone and salicylic acid; Preferably, the mass ratio of hydroquinone to salicylic acid is (1-2):

1.

7. The damping rubber composite material according to any one of claims 1 to 6, characterized in that: The thickness of the damping rubber composite material is 0.2-2 mm.

8. A method for preparing the damping rubber composite material according to any one of claims 1 to 7, characterized in that: The preparation method comprises the following steps: The raw materials including butyl rubber, recycled rubber, ethylene-vinyl acetate copolymer, low molecular weight amorphous α-olefin copolymer and inorganic filler are blended in one stage, and after cooling, a vulcanizing agent is added to carry out low-temperature mixing, open milling and vulcanization molding to obtain the damping rubber composite material.

9. The method for preparing the damping rubber composite material according to claim 8, characterized in that: The temperature of the first stage blending is 120-140°C; Preferably, the blending time is 7-10 min; Preferably, the low-temperature mixing temperature is 35-45°C; Preferably, the low-temperature mixing time is 3-5 min; Preferably, the refining of the lower sheet includes refining and triangle bagging; Preferably, the refining includes refining with left and right cutting knives; Preferably, the vulcanization molding temperature is 180-200°C.

10. Use of the damping rubber composite material according to any one of claims 1 to 7 in a speaker.

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