FR2903110A1 - MULTIPHASIC MIXTURE BASED ON GRANULATES OF ELASTOMERS CROSSLINKED IN POLYMERIC MATRIX WITH THERMOPLASTIC TRANSFORMATION - Google Patents

Abstract

The present invention relates to a heterogeneous multiphase mixture composed of at least one vulcanized elastomer in the form of aggregates, a crosslinkable or non-crosslinkable polymer matrix and various ingredients intended to improve acoustic properties or impact resistance without presenting a release The heterogeneously thermoplastically processable mixture is characterized in that it comprises, in addition to the thermoplastic matrix and vulcanized rubber granules, a swelling agent, fibers, compatibilizing agents, which may be vulcanizable elastomers. situ, and compounds intended either to reduce the effect of any unpleasant odors, or to hide them, depending on the use of said mixture on transformed products. The invention has many industrial applications, particularly in the production of acoustic screens for the automobile or the industry, in that of elements of body or components for the transfer of fluids having mechanical and sound-absorbing properties.

Description

The present invention relates to heterogeneous mixtures whose

  acoustic properties and impact resistance are improved while not giving off an unpleasant odor.

  STATE OF THE ART For the production of certain articles such as motor vehicle encapsulation components (cylinder head cover, side and undercarriages, undertray, etc.) or compressors (cowling), elements of sealing (trash lid), sound-absorbing components of the passenger compartment of a vehicle (deck seal, door panel, boot floor covering, etc.), bodywork elements (spoilers, bumper, hatch filling fuel, household appliances, etc.) or pipes, pipes, tubes or the like for the transfer of fluids (air supply duct, air filter housing, resonators, etc.), it is desirable to have materials which, having properties similar to those of thermoplastics, have intrinsic damping characteristics making it possible to improve the acoustic properties or those of shock absorption of these articles.

  The examples of cited articles, whose list is not exhaustive, are today made of plastic or thermoplastic elastomer consisting of a homogeneous mixture of a plastic phase and a lusturière phase tci, llh l 'ilOCl1C. uenity etnlll as_ ol I it IE. By nature, not with boronic propriety. These materials are recyclable, used, and mixed with a polyolefin resin and can contain various ingredients such as compatibilizers, pigments, plasticizers or various fillers. The heterogeneity of this type of mixture improves its properties of sound insulation, but its composition is at the origin of unpleasant odors of burned rubber forbidding its use for many applications. In addition, the presence of a polyolefin resin limits its use at moderate temperatures incompatible with those encountered in the vicinity of a heat engine.

OBJECT OF THE INVENTION The main object of the invention is to solve the new technical problem of providing a material whose acoustic properties and impact resistance are improved while not releasing little or no unpleasant odors. during its manufacture or use. It is therefore an object of the present invention to provide a material which, while being able to be used and processed on means derived from those used for elastomers or thermoplastics, has sound-insulating properties. and 20 shock absorption, and good resistance to heat, weather and chemical agents without being a source of gassing and odor deemed unpleasant or prohibitive for many applications. Ul '! , enton the fat source have transformed goose and economics while presenting one ouve the d! prover of use or of elastomi-based aniseed.

The present invention makes it possible to solve the technical problems mentioned above and relates to a heterogeneous multiphasic mixture composed of at least one vulcanized elastomer in the form of aggregates, of a crosslinkable or non-crosslinkable polymer matrix, and various ingredients for improving acoustic properties or impact resistance without presenting an unpleasant odor release. Said heterogeneously thermoplastically processed mixture is characterized in that it comprises, in addition to the thermoplastic matrix and vulcanized rubber granules, a swelling agent, fibers, compatibilizers, which may be vulcanizable elastomers in situ, and compounds intended either to reduce the effect of any unpleasant odors or to mask them, depending on the use of said mixture on transformed products. The invention has many industrial applications, particularly in the production of acoustic screens for the automobile or industry, particularly in the production of body components or components intended for the transfer of fluids having mechanical and sound-absorbing properties. . The present invention relates to a heterogeneous multiphase mixture composed of at least one vulcanized elastomer in the form of aggregates, a crosslinkable or non-crosslinkable polymer matrix and various ingredients for use in the field of acoustical properties. or to be of a type d), based on thermoplastic polymers, whether or not recycled, vulcanized rubber granules, one or more compatibilizing agents, at least one a blowing agent intended to create a cellular structure, allowing its use as a sound absorption medium or acoustic screen component The present invention also relates to a multiphase material with a heterogeneous structure, characterized in that it comprises a matrix base of thermoplastic polymers, recycled or not, vulcanized rubber granules, one or more compatibilizing agents, fibers, natural or synthetic, possibly sized, in particular to strengthen its structure while ensuring good acoustic properties. Advantageously, the material of the present invention comprises swelling agents and fibers, oriented or not.

Advantageously, the material comprises masking agents intended to limit the offgases likely to generate odors deemed unpleasant for the environment. Advantageously, the material also comprises one or more unvulcanized elastomers and crosslinking agents for causing the vulcanization reaction during the material mixing phase. Advantageously, the material further comprises fillers of clear or black carbon charges. Unusually, you have to protect yourself, to protect yourself by bringing a particular characteristic. 2903110 5 aesthetics, either protection or mechanical reinforcement, of a product component with sound-absorbing properties. The present invention furthermore relates to a material as described above, associated with internal and external coatings, intended to ensure the aesthetics and the protection, internal and external, as well as the mechanical reinforcement of a sandwich-type component with properties soundproofing. The present invention also relates to a method of manufacturing a material as described above, said method comprising the production of the material on industrial mixers allowing to reach a temperature sufficient to melt the thermoplastic phase, to disperse the various ingredients and to perform the possible vulcanization operation in situ, without degrading the vulcanized rubber granules incorporated. Advantageously, the process comprises a transformation, in particular by conventional means of the plastics industry by adapting the transformation conditions, to obtain a regular distribution in the thermoplastic matrix of the vulcanized rubber granules and the fibers, oriented or not, without degrading their physical state.

The invention relates to the use of a material as described above for the manufacture of soundproofing articles, such as motor encapsulation components, intended for the automobile, household appliances or industry, It is also possible to use them for absorbing shocks, such as pipes, ducts, bellows, filter housings, and the like. air, intended to reduce the noise caused by the passage of the fluid A preferred material is a heterogeneous multiphase mixture with thermoplastic transformation, characterized in that it comprises at least one type of vulcanized rubber granules, a polymer matrix composed of thermoplastics optionally recycled, such as polyolefins, polyamides or a mixture of several families to which a vulcanized elastomer may be associated, homogeneously mixed, optionally agents for suppressing or masking; odor, from rubber granules or thermoplastic matrix, and ingredients such as compatibilizers, plasticizers, or various fillers to adjust the characteristics as needed by the user and to facilitate processing during manufacture of the material or that of the products.

Advantageously, the multiphase mixture will comprise a blowing agent intended to increase the heterogeneity of the mixture after transformation so as to favor the acoustic screen effect by trapping sound waves received by a wall made of such a material. In addition to the favorable weight gain for many applications, the alternation within the heterogeneous structure of the material of elastic elements (rubber granules) and voids created by the gassing of the blowing agent is particularly effective in smothering the acoustic waves in the case of use in screen or absorbing coating in one other mode of codon n (= -. f ^ -1, inventInri iHMF 25 cric res may be coconut, etc. .) 2903110 7 automobile engine air intake, made with such a multiphase material, to withstand an internal depression while limiting its acoustic radiation. The aggregates are preferably derived from used tires or other rubber articles such as pipes or bellows, or manufacturing waste from the rubber industry (molding mats, injection cores, rejects, etc.). The products obtained with such a material can themselves be recycled after grinding, or recovered by various means, such as the production of thermal energy.

Advantageously, the aggregates are pretreated by immersions in the oil to serve as a plasticizer, in particular by releasing the oil. The possibility of using recycled materials in their composition and their own end-of-life recycling of components made with these 15 multiphase mixtures is also an interesting step towards meeting environmental standards and lowering production costs. Their use and their use must not, however, be a source of unpleasant gaseous release, in particular for confined rooms (engine compartment, interior of a passenger compartment, etc.). Thus by using the heterogeneous multiphase mixture according to the present invention, such recycled materials can be used. For some use to provide for the incorporation of an odorant, such as a perfume, or an odor suppressant or masking agent. e Ill! Iriic, for! o = uslonments usuirItL, les te r arir, j 'en niques and 1 es or quoted 2903110 limiting, with reference to the accompanying drawings in which: - Figure 1 represents an example of material structure object of the present invention comprising various components for improving its acoustic performance. FIG. 2 represents a structure of the above type in which fibers designed to improve the mechanical strength have been incorporated. Figure 3 shows a structure of the above type in which the fibers have been oriented. Figure 4 shows a structure of the multilayer type. According to the present invention, a multiphase material having intrinsic soundproofing properties, the structure of which is shown in FIG. 1, comprises a thermoplastic phase (1), recycled or not, vulcanized rubber granules (2), originating from shredders from used tires or industrial rubber waste, one or more compatibilizing agents, for example an grafted polypropylene type maleic anhydride or SEBS (Styrene Ethylene Butylene Styrene) grafted or ungrafted, one or more blowing agents, for example of the type Azodicarbonamide or Oxybis Benzene Sulfonyl Hydrazine, intended to reduce the density of the structure while increasing its heterogeneity by creating cells (3). Depending on the application, an elastomer is added (cannulated at the anti-aging phase, for example) between the granules. An anti-aging system is then used to stabilize the heat. clear charges for the reinforcement 2903110 9 necessary for certain sound-absorbing systems, or plasticisers intended to facilitate the mixing operation, Such a structure may also comprise fibers (4) intended to reinforce the mechanical strength as represented in FIG. The mixture obtained is in the form of transformable granules such as thermoplastics used in the industry by known means such as calendering, stamping, thermoforming, blowing, injection and extrusion.

For some cylindrical products, such as sealing pipes or bellows, the presence of fibers allows mechanical reinforcement improving the resistance to pressure or depression. According to a known method, this resistance is improved by a three-dimensional orientation of the fibers using a "venturi" type die. Figure 3 shows a cylindrical element made by this technique. For other applications, it may be advantageous to obtain multilayer walls, the material according to the present invention being associated with at least one other material (5) or (6), as shown in FIG. , generally thermoplastics, must be compatible with the polyphasic material with sound-absorbing property. They may allow either to give an aesthetic exterior appearance, such as in the case of an automobile engine cylinder head cover or various cowlings, or the like. Other purposes, features and advantages of the invention will become apparent to those skilled in the art from the reading of the explanatory description which is incorporated herein by reference. Reference is made to examples which are given by way of illustration only and which in no way limit the scope of the invention.Examples form an integral part of the present invention and any features appearing novel with respect to a state of the art. Any prior art from the description taken as a whole, including the examples, is an integral part of the invention in its function and in its generality, so that each example has a general scope. On the other hand, in the examples, all percentages are by weight unless otherwise indicated.

EXAMPLES A non-limiting example of a formulation according to the present invention comprises, for a 100% by weight basis of thermoplastic matrix, the following composition: Example No. 1: Recycled or non-recycled PP 100 Rubber aggregate 30 to 70 5 to 15 g / cm 3 at 40% to 20% Protection grade L as 040 2903110 11 Plasticizers o to 40 Blowing agents 2 to 10 Cellulose fiber o to 30 Elastomer crosslinking system 0 to 10 Formulas of the above type can be used for disadvantage of giving off unpleasant odors, for example inside a passenger compartment of a motor vehicle. It will then be advantageous to add to the formula odor absorbers of the wood flour or zeolite type, or even masking agents such as castor oil. The formula of Example No. 2 relates to a mixture of ethylene-propylene-diene-monomer rubber (EPDM) granules, which makes it possible to obtain a thermal resistance greater than that of natural rubber, resulting for example from tire shreds. Used. It comprises a tackifying resin intended to improve the compatibility between the thermoplastic matrix, in the example of polypropylene, and the EPDM rubber associated with compatibilization systems, for example a maleic anhydride grafted polypropylene or a grafted or non-grafted SEBS. By way of examples, mention may be made of styrenic resins or hexamethylene tetramine. Vanilin is a perfume conventionally used for EPDM. Example No. 2 also uses antistatic agents, such as a conductive carbon black, and clear fillers of the semi-reinforcing type, such as talc. Silica 2903110 12 Example re 2 PP 100 Rubber aggregate EPDM 30 to 70 Virgin EPDM rubber 0 to 40 Compatibilizer 5 to 15 Homogenising resin o to 20 Odor adsorbers 10 to 20 Castor oil 5 to 10 Vanilin 1 to 5 System 2 to 5 Heat Stabilizer 2 to 5 Charges 0 to 40 Antistatic Agents 5 to 10 Organic Peroxides 0 to 10 Example 3 describes the formula of a relatively flexible material having good resistance to oils. The aggregates are obtained from vulcanized rubber crushes based on nitrile NBR or hydrogenated nitrile HNBR. NBR or HNBR virgin rubber is added to improve the compatibilization between aggregates and the polymer constituting the matrix (in this case polypropylene) and to bring a thermoplastic character to the final mixture in addition to conventional compatibilization systems such as a polyurethane urethane. . Example 3: PP 100 NBR or HNBR Rubber Granule 30 to 70 Virgin Rubber NBR or HNBR o to 40 Compatibilizer 5 to 15 Homogenizing Resin o to 20 Protection System 2 to 5 Heat Stabilizer 2 to 5 Loads 0 to 10 Vulcanization System 0 to 10 Example No. 4 represents a formula according to the invention intended to exhibit, in addition to good soundproofing characteristics, good resistance to high temperatures and oils. The matrix consists of a high melting point polymer such as polyamide. The aggregates are derived from ethyl acrylate copolymer rubber grinders, for example of the ACM or AEM type, mixed with a non-vulcanized elastomeric phase, comprising its vulcanization system for vulcanization in situ during the mixing phase. Example 4: PA 100 25: ac equivalent 3 40 ic virgin p, CM or Al 0 to 40 pat, a 2 to 5 2 to 5 0 to 20 2903110 14 Charges o to 30 Polymer vulcanization system 0 to 10 L Example No. 5 relates to a formula for the production of flexible articles based on a cheap material with low mechanical characteristics. The level of aggregates is important to significantly reduce flexural modulus. The high flexibility is obtained by a high dilution ratio (fillers + plasticizer). An agent of implementation is generally necessary with such dilution rates. Example 5: PP Granulates 15 Compatibilizer Virgin Elastomer Protection System Heat Stabilizer Processing Agent 20 Plasticizer Loads Vulcanization System Represents UHFHUHHUHHUHHUHHUHHUHHUHHUHHUHHHHHHHHHHHHHHHHHQH 100 40 to 80 5 to 15 o to 60 2 to 5 2 to 5 2 to 10 0 to 60 o to 60 o to 30 0 grafted maleic anhydride or SEBS grafted or not, the other for grafted or ungrafted SEBS type polyamide or EVA (Ethylene Vinyl Acetate) The addition of a flame retardant makes it possible to improve the fire behavior of products made with such a material Exempt No. 6: PP PA 10 EPDM rubber granules uncrosslinked Compatibilizer 1 Compatibilizer 2 Homogenizing resin 15 Heat Stabilizer Flame Retardant Charges Organic Peroxides Coagent Example 7 is a formula of a temperature and oil resistant material as can be used for realizing crankcase oil E 'engine oil reutorr ~ ohile (iRrlS from 65 to 85 15 to 35 10 to 50 0 to 50 5 to 15 5 to 15 o to 20 2 to 5 2 to 5 o to 20 o to 40 2 to 10 1 to 5 I laot 5 EVA.

2903110 Example no. 7 ABS 100 Rubber aggregates ACM, AEM, NBR 10 to 50 5 Virgin rubber ACM or AEM or NBR o to 30 Compatibilizer 5 to 15 Protection system 2 to 5 Heat stabilizer 2 to 5 Flame retardant o to 20 10 Charges 0 to 30 Elastomeric vulcanization system 0 to 10 These various non-limiting examples represent embodiments of materials in accordance with the present invention.

These materials are achievable using blending tools known to manufacturers. The mixers used must make it possible to reach the melting temperature of the thermoplastic phase and to carry out the mixing without degrading the vulcanized rubber granules by too high shear thereof. 6

Claims (6)

  1. A multiphase material heterogeneous structure, characterized in that it comprises a matrix based on thermoplastic polymers, recycled or not, vulcanized rubber granules, one or more compatibilizing agents, at least one blowing agent intended to create a cellular structure, allowing its use as a sound absorption medium or acoustic screen component.   2. Polyphasic material heterogeneous structure, characterized in that it comprises a matrix based on thermoplastic polymers, recycled or not, vulcanized rubber granules, one or more compatibilizing agents, fibers, natural or synthetic, possibly sized.   3. Material according to any one of claims 1 and 2 characterized in that it comprises swelling agents and fibers, oriented or not.   4. Material according to any one of the preceding claims, characterized in that it comprises masking agents intended to limit the gaseous releases likely to generate odors deemed unpleasant for the environment.   5. Material according to any one of the preceding claims, characterized in that it also comprises one or more unvulcanized elastomers and crosslinking agents intended to cause the vulcanization reaction [-lant the phase e-mixing t-riater iau . 25   6. I .e rc (i carac amprE plus, ype charges loads.) 8. Material according to any one of the preceding claims, associated with an outer coating, intended to ensure either aesthetics or protection, or a mechanical reinforcement, a product component with sound-absorbing properties 9. Material according to any one of the preceding claims, associated with internal and external coatings, intended to ensure aesthetics and protection, internal and external, as well as The method of manufacturing a material according to any one of claims 1 to 9, comprising the production of the material on industrial mixers to achieve a temperature. sufficient to melt the thermoplastic phase, to disperse the various ingredients and to carry out the possible vulcanization operation in situ, without degradative and vulcanized rubber granules incorporated. 11. The method of claim 10, characterized in that it comprises a transformation to obtain a regular distribution in the thermoplastic matrix vulcanized rubber granules and fibers, oriented or not, without degrading their physical state. 12. Use of a material according to any one of claims 1 to 9 for the manufacture of soundproofing articles, such as motor encapsulation components, intended for the automobile, household appliances or industry . 13. Use of a material according to any one of claims 1 to 9 for the manufacture of body or closure elements, intended to absorb shock by limiting the acoustic impact thereof. 14. Use of a material according to any one of claims 1 to 9 for the production of fluid circulation elements such as pipes, ducts, bellows, air filter housings, intended to reduce the noise caused by the passage fluid.