PROCESS FOR THE MANUFACTURE OF EPDM-SILICONE HYBRID PRODUCTS

Abstract

The invention relates to a process for the manufacture of hybrid products comprising at least two different elastomer materials bonded to each other, said at least two different elastomer materials being based on at least one rubber of the ethylene propylene diene monomer (EPDM) type and at least one rubber of the silicone type wherein the silicone rubber comprises alkenyl functionalized polydialkylsiloxanes. The inventive process is particularly useful for the manufacture of EPDM-silicone hybrid sealing profiles.

Claims

1. A process for the manufacture of hybrid products comprising at least two different elastomer materials bonded to each other, said at least two different elastomer materials being based on at least one rubber of the ethylene propylene diene monomer (EPDM) type and at least one rubber of the silicone type; wherein said at least one EPDM rubber material and said at least one silicone rubber material are covulcanized in contact with each other in the presence of a peroxide curing agent; and wherein said at least one silicone rubber comprises alkenyl functionalized polydialkylsiloxanes of the general formula:
R.sub.3Si—[O—SiR.sub.2].sub.n—O—SiR.sub.3; wherein R is selected from the group consisting of C.sub.1-C.sub.8 alkyl and C.sub.1-C.sub.8 alkenyl groups, and n is a natural number specifying the number of repeating units.

2. The process of claim 1, wherein the C.sub.1-C.sub.8 alkyl groups are selected from the group consisting of methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert.-butyl, n-pentyl, iso-pentyl, n-hexyl, iso-hexyl, n-heptyl, iso-heptyl, n-octyl and iso-octyl groups, and the C.sub.1-C.sub.8 alkenyl groups are selected from the group consisting of ethenyl (vinyl), n-propenyl, iso-propenyl, n-butenyl, iso-butenyl, tert.-butenyl, n-pentenyl, iso-pentenyl, n-hexenyl, iso-hexenyl, n-heptenyl, iso-heptenyl, n-octenyl and iso-octenyl groups.

3. The process of claim 1 or 2, wherein the diene component of the EPDM rubber is a conjugated or non-conjugated diene.

4. The process of claim 3, wherein the diene component is selected from the group consisting of 5-methylene-2-norbornene, 5-ethylidene-2-norbornene, cyclooctadiene, 2-methyl-1,4-pentadiene, 1,4-hexadiene, 4-methyl-1,4-hexadiene, 1,4-heptadiene, 4-methyl-1,4-heptadiene, 4-ethyl-1,4-heptadiene, 1,5-heptadiene, 1,5-octadiene, 5-methyl-1,5-heptadiene, 2-methyl-1,5-hexadiene, 1,6-octadiene, 6-methyl-1,6-octadiene, 2-methyl-1,6-heptadiene, 1,9-decadiene, 1,13-tetradecadiene, vinylcyclohexene, vinylnorbornene, dicyclopentadiene, 1,3,7-octatriene, and 1,5,9-decatriene.

5. The process of any one of the preceding claims, wherein the peroxide curing agent is selected from the group consisting of acetyl peroxide, benzoyl peroxide, lauroyl peroxide, bis-(2,4-dichlorobenzoyl)peroxide, dicumyl peroxide, tert-butyl peroxyperbenzoate, tert-butyl peroxypivalate, di-tert-butyl peroxide, 2,5-bis-(tert-butylperoxy)-2,5-dimethylhexane, and bis(tert-butyl peroxy isopropyl)benzene.

6. The process of any one of the preceding claims, wherein three or four different elastomer materials are used.

7. The process of any one of the preceding claims, wherein two different EPDM rubber materials and one silicone rubber material, or one EPDM rubber material and two silicone rubber materials are used.

8. The process of any one of the preceding claims, wherein the hybrid product is manufactured directly by coextrusion of a curable composition comprising a suitable EPDM compound and a curable composition comprising a suitable alkenyl functionalized polydialkylsiloxane compound on a coextruder, followed by covulcanization.

9. The process of any one of the preceding claims, wherein the silicone rubber is present on the surface of the hybrid product.

10. The process of claim 9, wherein the thickness of the applied silicone rubber is variable.

11. The process of claim 9 or 10, wherein the lowest thickness of the applied silicone rubber is 2 to 0.01 mm.

12. The process of claim 11, wherein the lowest thickness is 0.5 to 0.05 mm.

13. The process of any one of the preceding claims, wherein the covulcanization is performed at a temperature in the range of 180 to 270° C.

14. The process of any one of the preceding claims, wherein the covulcanization is performed for a period of from 30 seconds to 30 minutes.

15. EPDM-silicone hybrid sealing profile obtainable by the process according to any of claims 1 to 14.

16. Use of the process of any one of the preceding claims for the manufacture of EPDM-silicone hybrid sealing profiles.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] FIG. 1 is a sectional view of an EPDM-silicone hybrid sealing profile manufactured using the inventive process.

[0047] FIG. 2 is a sectional view of an EPMD-silicone (EPDM-silicone) hybrid sealing profile wherein a part of the grooves are covered with a thin layer of silicone.

[0048] FIG. 3 is a sectional view of an EPMD-silicone hybrid sealing profile wherein all the grooves are covered with a thin layer of silicone.

[0049] FIG. 4 is a sectional view of a further embodiment of an EPDM-silicone hybrid sealing profile wherein a part of the surface is covered with a thin layer of silicone. TLT=Thin Layer Technology.

[0050] FIG. 5 is a sectional view of a further embodiment of an EPDM-silicone hybrid profile wherein a thin layer of silicone is extruded on the EPDM part also around the foot of the EPDM-silicone hybrid profile.

[0051] FIG. 6 is a schematic representation of coextrusion which can be used in the invention.

[0052] FIG. 7 is a schematic drawing of triple-extrusion which can be used in the invention.

[0053] FIG. 8 is a schematic drawing of quattro-extrusion which can be used in the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0054] While certain representative embodiments and details have been shown for the purpose of illustrating the present invention, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the present invention.

[0055] FIG. 1 shows an EPDM-silicone hybrid sealing profile 10 having a sealing section 14 and a groove 15 which can be used for mating the EPDM-silicone hybrid sealing profile 10 to a window or a door frame.

[0056] The sealing section 14 consists of a first elastomer material 11 being silicone having a length 102 of 5.5±0.7 cm.

[0057] The foot 15 consists of a second elastomer material 12 being EPDM and comprises a bridge 17 and a hook or a groove 16. The bridge 17 has a length 103 of 1.6±0.15 cm. The foot 15 comprises a core 18 inside the foot 15 having a length 104 of 2.4 cm. The foot 15 further provides a recess for a cord 13.

[0058] The sealing section 14 is coupled to the groove 15 at a joining section 19 which provides a positive locking, non-positive locking and/or a bonded joint.

[0059] FIGS. 2 to 5 show alternative embodiments of an EPDM-silicone hybrid sealing profile described above. The same or functionally identical parts may use the above mentioned reference signs.

[0060] FIG. 2 shows a second embodiment of the EPDM-silicone hybrid sealing profile 20. The shown embodiment consists of a first elastomer material 21 being silicone and a second elastomer material 22 being EPDM. The foot 15 of the shown embodiment has a multiple of grooves 16. The first elastomer material 21 can extend along the outer surface of some of the grooves 26 such that a part of the grooves 26 are covered with a thin layer of silicone.

[0061] FIG. 3 shows a third embodiment of the EPDM-silicone hybrid sealing profile 30. The shown embodiment consists of a first elastomer material 31 being silicone and a second elastomer material 32 being EPDM. The first elastomer material 31 can extend along the outer surface of the grooves 36 such that all of the grooves 26 are covered with a thin layer of silicone.

[0062] FIG. 4 shows a forth embodiment of the EPDM-silicone hybrid sealing profile 40 comprising a first elastomer material 41 being TLT Silicone and a second material 42. The first elastomer material 41 covers with a thin layer of silicone a section of the second elastomer material 42.

[0063] FIG. 5 shows a fifth embodiment of the EPDM-silicone hybrid sealing profile 50 comprising a first elastomer material 51 being Silicone 60, a second elastomer material 52 being high friction silicon of an alternative special colour, a third elastomer material 53 being high friction silicon, a forth elastomer material 55 being EPDM 80 to 90 sh and a fifth elastomer material 56 being low friction EPDM.

[0064] A thin layer of the second elastomer material 52, the third elastomer material 53 and the fifth elastomer material 56 is extruded on the forth elastomer material 55.

[0065] FIG. 6 shows a coextrusion system comprising a first extruder 61 and a second extruder 62 providing elastomer material to a die 65 to produce a EPDM-silicone hybrid profile 66 as shown in FIGS. 1 to 4.

[0066] FIG. 7 shows a triple-extrusion system 71 comprising a first extruder 71, a second extruder 72 and a third extruder 73 providing elastomer material to a die 75 to produce a EPDM-silicone hybrid profile 76.

[0067] FIG. 8 shows a quattor-extrusion 81 comprising a first extruder 81, a second extruder 82, a third extruder 83 and a forth extruder 84 providing elastomer material to a die 85 to produce a EPDM-silicone hybrid profile 86 as shown in FIG. 5.

REFERENCE SIGNS

[0068] 10 EPDM-silicone hybrid sealing profile

[0069] 11 first elastomer material

[0070] 12 second elastomer material

[0071] 13 cord

[0072] 14 sealing section

[0073] 15 groove

[0074] 16 hook

[0075] 17 bridge

[0076] 18 core

[0077] 19 joining section

[0078] 101 thickness of first elastomer material

[0079] 102 length of sealing section

[0080] 103 length of bridge

[0081] 104 length of core

[0082] 20 EPDM-silicone hybrid sealing profile

[0083] 21 first elastomer material

[0084] 22 second elastomer material

[0085] 30 EPDM-silicone hybrid sealing profile

[0086] 31 first elastomer material

[0087] 32 second elastomer material

[0088] 33 third elastomer material

[0089] 34 cord

[0090] 40 EPDM-silicone hybrid sealing profile

[0091] 41 first elastomer material

[0092] 42 second elastomer material

[0093] 50 EPDM-silicone hybrid sealing profile

[0094] 51 first elastomer material

[0095] 52 second elastomer material

[0096] 53 third elastomer material

[0097] 54 forth elastomer material

[0098] 55 fifth elastomer material

[0099] 56 sixth elastomer material

[0100] 60 coextruder

[0101] 61 first coextruder

[0102] 62 second coextruder

[0103] 65 die

[0104] 66 EPDM-silicone hybrid sealing profile

[0105] 70 triple-extruder

[0106] 71 first coextruder

[0107] 72 second coextruder

[0108] 73 third coextruder

[0109] 75 die

[0110] 76 EPDM-silicone hybrid sealing profile

[0111] 80 quattro-extruder

[0112] 81 first coextruder

[0113] 82 second coextruder

[0114] 83 third coextruder

[0115] 84 forth coextruder

[0116] 85 die

[0117] 86 EPDM-silicone hybrid sealing profile