ARTICLE, IN PARTICULAR FOR AN AIR SPRING BELLOWS

Abstract

An article having a multilayer base unit with elastic properties has at least one inner layer A and at least one textile reinforcement layer B and at least one intermediate layer C and at least one outer layer D, at least one intermediate layer C of the base unit being formed from a rubber compound that includes chloroprene rubber (CR) or chlorosulfonated polyethylene (CSM) or alkylated chlorosulfonated polyethylene (ACSM) or chlorinated polyethylene (CM) or chlorobutyl rubber (CIIR) or bromobutyl rubber (BIIR) or polyepichlorohydrin rubber (CO; ECO; ETER) or brominated copolymer of isobutylene and paramethylstyrene (BIMS), in each case alone or in combination, and 3 to 40 phr of at least one intumescent flame retardant, and the intermediate layer C being in direct contact with a textile reinforcement layer B.

Claims

1. An article comprising: a multilayer base unit with elastic properties having at least one inner layer, at least one textile reinforcement layer, at least one intermediate layer, and at least one outer layer, wherein the at least one intermediate layer of the multilayer base unit is formed from a rubber compound that comprises: one or more of chloroprene rubber (CR) or chlorosulfonated polyethylene (CSM) or alkylated chlorosulfonated polyethylene (ACSM) or chlorinated polyethylene (CM) or chlorobutyl rubber (CIIR) or bromobutyl rubber (BIIR) or polyepichlorohydrin rubber (CO; ECO; ETER) or brominated copolymer of isobutylene and paramethylstyrene (BIMS), and 3 to 40 phr of at least one intumescent flame retardant, wherein the at least one intermediate layer is in direct contact with the at least one textile reinforcement layer.

2. The article according to claim 1, wherein the total amount of CR, CSM, ACSM, CM, CIIR, BIIR, CO, ECO, ETER, BIMS, in each case alone or in combination, is between 50 and 100 phr.

3. The article according to claim 2, wherein the total amount of CR, CSM, ACSM, CM, CIIR, BIIR, CO, ECO, ETER, BIMS, in each case alone or in combination, is 100 phr.

4. The article according to claim 1, wherein the at least one intumescent flame retardant is an expandable graphite or a mixture of two or more different expandable graphites.

5. The article according to claim 1, wherein the article is an air spring bellows, a tubular body or a drive belt.

6. The article according to claim 1, wherein the article as a whole satisfies the requirements of the EN-45545 standard.

7. The article according to claim 1, wherein the at least one intumescent flame retardant is present in an amount from 5 to 30 phr.

8. The article according to claim 1, wherein the at least one intumescent flame retardant is present in an amount from 10 to 25 phr.

9. The article according to claim 1, wherein the at least one intumescent flame retardant is a physically acting intumescent flame retardant.

10. The article according to claim 1, wherein the rubber compound is free from chemically acting intumescent flame retardant.

11. The article according to claim 1, wherein the rubber compound is free from halogen-containing flame retardant.

12. The article according to claim 1, wherein the at least one intumescent flame retardant is only an intumescent expandable graphite in the amount from 3 to 40 phr, and the rubber compound is void of other flame retardant material.

13. The article according to claim 1, wherein the at least one intumescent flame retardant includes a intumescent expandable graphite having an onset temperature above 180? C.

14. The article according to claim 1, wherein the at least one intumescent flame retardant includes a physically acting intumescent expandable graphite having an onset temperature above 200? C.

15. The article according to claim 1, wherein the at least one intumescent flame retardant includes a physically acting intumescent expandable graphite having an onset temperature above 220? C.

16. A method of forming an article, comprising: providing a layer formed from a rubber compound that comprises: (i) one or more of chloroprene rubber (CR) or chlorosulfonated polyethylene (CSM) or alkylated chlorosulfonated polyethylene (ACSM) or chlorinated polyethylene (CM) or chlorobutyl rubber (CIIR) or bromobutyl rubber (BIIR) or polyepichlorohydrin rubber (CO; ECO; ETER) or brominated copolymer of isobutylene and paramethylstyrene (BIMS), and (ii) 3 to 40 phr of at least one intumescent flame retardant; heating the layer to an onset temperature of the at least one intumescent flame retardant that causes the layer to foam; and forming an article with the layer as at least one intermediate layer, wherein: the article includes a multilayer base unit with elastic properties having at least one inner layer, at least one textile reinforcement layer, the at least one intermediate layer, and at least one outer layer, wherein the at least one intermediate layer is in direct contact with the at least one textile reinforcement layer.

17. The method according to claim 16, wherein the at least one intumescent flame retardant includes an intumescent expandable graphite having an onset temperature above 180? C.

Description

DETAILED DESCRIPTION

[0057] The invention is now elucidated further on the basis of working examples with reference to schematic drawings and laboratory experiments. The invention is not limited to these exemplary embodiments. Shown below:

[0058] FIG. 1 shows an exemplary layer structure of an article, preferably an air spring, a vibration damper or a damping element.

[0059] The article includes a multilayer base unit with elastic properties having at least one inner layer A and at least one textile reinforcement layer B and at least one intermediate layer C and at least one outer layer D. The intermediate layer C according to the invention is here situated between the reinforcement layer B and the outer layer D.

[0060] In Table 1 the upper section shows the composition of a layer C that is in direct contact with a reinforcement layer B. The lower section shows the corresponding laboratory data. V1 represents a reference compound without expandable graphite. E1 and E2 are each compositions according to the invention with expandable graphite.

TABLE-US-00001 TABLE 1 V1 E1 E2 Composition of the compound CR phr 100.00 100.00 100.00 Carbon black phr 40.00 40.00 40.00 Di-2-propylheptyl phr 8.00 8.00 8.00 phthalate ZnO phr 6.00 6.00 6.00 Zinc stearate, phr 5.00 5.00 5.00 stearic acid, wax MgO phr 4.00 4.00 4.00 MMBI phr 1.00 1.00 1.00 Diarylphenyl- phr 3.00 3.00 3.00 enediamine Octylated phr 5.00 5.00 5.00 diphenylamine MBTS phr 1.00 1.00 1.00 Expandable phr 0.00 12.00 24.00 graphite Experimental results Vulcanization min/? C. 30/160 30/160 30/160 conditions Density g/ccm 1.33 1.36 1.39 (ISO 1183-1) Hardness Sh A 58.0 60.0 63.0 (ISO 7619-1) Tensile strength MPa 18.1 14.2 10.4 (ISO 37) Elongation at % 618.2 511.4 425.9 break (ISO 37) 50% modulus MPa 1.2 1.3 1.4 100% modulus MPa 1.7 1.7 1.8 200% modulus MPa 3.7 3.6 3.6 300% modulus MPa 7.1 6.9 6.6 400% modulus MPa 10.56 10.38 9.76 500% modulus MPa 14.2 14 Thickness: mm 5.7 2.47 2.41 Initial mass: g 76.7 31.67 33.321 Time to ignition: sec 157 56 55 Time to flameout: sec 683 170 183 Mass lost g 41.8 21.7 14.4 Specific mass lost kg/m.sup.2 2.46 1.62 Percentage mass % 54.5 68.6 43.1 lost