METHOD FOR PRODUCING A RUBBER-PLASTIC COMPOSITE

Abstract

A method for producing a rubber-plastic composite, including the steps of (a) shaping an unvulcanized elastomer, (b) partially vulcanizing the shaped elastomer at a temperature of at least 140° C. up to a degree of vulcanization in the range from 10% to 40%, (c) cooling the partially vulcanized elastomer to a temperature of less than 100° C. within less than 20 minutes, (d) overmolding the partially vulcanized elastomer with a plastic, and (e) heat treating the partially vulcanized elastomer overmolded with a plastic at a temperature in the range from 100° C. to 170° C. for a duration of from 5 minutes to 5 hours to complete the vulcanization and form a rubber-plastic composite. The method further relates to a rubber-plastic composite obtainable by the method according to the invention and also to a shoe comprising the rubber-plastic composite obtainable by the method according to the invention.

Claims

1.-15. (canceled)

16. A method for producing a rubber-plastic composite, comprising the following steps: a) shaping an elastomer which is unvulcanized to form a shaped elastomer, b) partially vulcanizing the shaped elastomer at a temperature of at least 140° C. up to a degree of vulcanization in the range from 10% to 40% to form a partially vulcanized elastomer, c) cooling the partially vulcanized elastomer to a temperature of less than 100° C. within less than 20 minutes, d) overmolding the partially vulcanized elastomer with a plastic, and e) heat treating the partially vulcanized elastomer overmolded with the plastic at a temperature in the range from 100° C. to 170° C. for a duration of from 5 minutes to 5 hours to complete the vulcanization and thus forming the rubber-plastic composite; wherein the plastic is polyamide (PA) and the elastomer is (partially) hydrogenated nitrile rubber (HNBR).

16. The method as claimed in claim 16, wherein in step b) the vulcanization is conducted up to a degree of vulcanization in the range from 10% to 20%.

17. The method as claimed in claim 16, wherein the partially vulcanized elastomer in step c) is cooled to a temperature of less than 80° C. within less than 5 minutes.

18. The method as claimed in claim 16, wherein the heat treatment in step e) is conducted at a temperature of at least 120° C. and less than 140° C. for a duration of from 1 to 3 hours.

19. The method as claimed in claim 16, wherein the plastic contains no reinforcers or fillers.

20. The method as claimed in claim 16, wherein the plastic contains no glass fibers or graphite.

21. The method as claimed in claim 16, wherein the method does not include the use of an adhesion promoter.

22. The method as claimed in claim 16, wherein steps a) and b) are conducted simultaneously in a vulcanizing press.

23. The method as claimed in claim 16, wherein the partially vulcanized elastomer after step c) is placed into an injection mold and step d) is conducted in said mold.

24. The method as claimed in claim 16 further comprising incorporating the rubber-plastic composite into a shoe.

25. A method for producing a rubber-plastic composite, comprising the following steps: a) shaping an elastomer which is unvulcanized to form a shaped elastomer, b) partially vulcanizing the shaped elastomer at a temperature of at least 140° C. up to a degree of vulcanization in the range from 10% to 40% to form a partially vulcanized elastomer, c) cooling the partially vulcanized elastomer to a temperature of less than 100° C. within less than 20 minutes, d) overmolding the partially vulcanized elastomer with a plastic, and e) heat treating the partially vulcanized elastomer overmolded with the plastic at a temperature in the range from 100° C. to 170° C. for a duration of from 5 minutes to 5 hours to complete the vulcanization and thus forming the rubber-plastic composite.

26. The method as claimed in claim 29, wherein a plastic and the elastomer are a combination selected from the group consisting of polyacrylate rubber (ACM) with polyamide (PA); ethylene-acrylate rubber (AEM/EAM) with PA or polyphthalamide (PPA); ethylene-propylene-diene copolymer (EPDM) with polyphenylene ether (PPE) or PA; fluoro rubber (FKM) with PA or PPA; (partially) hydrogenated nitrile rubber (HNBR) with PA or PPA; natural rubber (NR)/styrene-butadiene rubber (SBR), SBR, SBR/EPDM or SBR/nitrile-butadiene rubber (NBR) with PPE; methyl-vinyl-silicone rubber (VMQ) with PA or PPA; and carboxylated nitrile rubber (XNBR) with PA.

27. The method as claimed in claim 25, wherein the plastic is polyamide (PA) and the elastomer is (partially) hydrogenated nitrile rubber (HNBR).

28. The method as claimed in claim 25, wherein the elastomer is selected from the group consisting of polyacrylate rubber (ACM), ethylene-acrylate rubber (AEM/EAM), ethylene-propylene-diene copolymer (EPDM), ethylene-propylene copolymer (EPM), fluoro rubber (FKM), (partially) hydrogenated nitrile rubber (HNBR), carboxylated nitrile rubber (XNBR), nitrile-butadiene rubber (NBR), natural rubber (NR), styrene-butadiene rubber (SBR), methyl-vinyl-silicone rubber (VMQ), polybutadiene rubber (BR), polyisoprene rubber (IR), and combinations thereof.

29. The method as claimed in claim 25, wherein the plastic is selected from the group consisting of polyamide (PA), polyphenylene ether (PPE), polyphthalamide (PPA), polyurethane (PU), polyether block amide (PEBA), and combinations thereof.

30. The method as claimed in claim 25, wherein the plastic is present in the form of a thermoplastic elastomer (TPE) or as a thermoplastic elastomer alloy with a rubber selected from the group consisting of polyacrylate rubber (ACM), ethylene-acrylate rubber (AEM/EAM), ethylene-propylene-diene copolymer (EPDM), ethylene-propylene copolymer (EPM), fluoro rubber (FKM), (partially) hydrogenated nitrile rubber (HNBR), carboxylated nitrile rubber (XNBR), nitrile-butadiene rubber (NBR), natural rubber (NR), styrene-butadiene rubber (SBR), methyl-vinyl-silicone rubber (VMQ), polybutadiene rubber (BR), polyisoprene rubber (IR), and combinations thereof.

31. The method as claimed in claim 25, wherein steps a) and b) are conducted simultaneously in a vulcanizing press.

32. The method as claimed in claim 25, wherein the method does not include the use of an adhesion promoter.

33. The method as claimed in claim 25, wherein in step b) the vulcanization is conducted up to a degree of vulcanization in the range from 10% to 20%, wherein the partially vulcanized elastomer in step c) is cooled to a temperature of less than 80° C. within less than 5 minutes, and wherein the heat treatment in step e) is conducted at a temperature of at least 120° C. and less than 140° C. for a duration of from 1 to 3 hours.

34. The method as claimed in claim 25, wherein the plastic contains no reinforcers or fillers.

35. The method as claimed in claim 25 further comprising incorporating the rubber-plastic composite into a shoe.

Description

EXAMPLES

[0025] Rubber-plastic composites were produced by the method according to the invention, using an HNBR rubber and a PA612 plastic. The vulcanization was effected at a temperature of 140° C. up to a degree of vulcanization of 20%. Thereafter, it was cooled to a temperature of 40° C. within 20 minutes. This was followed by overmolding with the plastic and subsequent heat treatment at 130° C. for 2 hours.

[0026] The rubber-plastic composites obtained were subjected to a separation test in order to determine how much force is required for the separation (i.e. until complete detachment or until detachment until tearing) of rubber and plastic. The results are presented in table 1 below. For each example, four samples were produced and measured, with the table below giving the average value for each of the four samples and also the standard deviation in parentheses.

TABLE-US-00001 TABLE 1 Sample Separation Cohesive width Force resistance fraction [mm] [N] [N/mm] [%] Example 1 14.08 89.1 (8.1) 6.3 (0.4) 96 (3) (n = 4) (0.81) Example 2 14.36 59.7 (9.5) 4.2 (0.7)  5 (4) (reference) (0.08) (n = 4)

[0027] Example 1 describes the measurement results for a rubber-plastic composite that was produced by the method according to the invention, whereas in the method for producing the rubber-plastic composite according to example 2 the final step of thermal aftertreatment was omitted. It is found that the composite produced by the method according to the invention requires a much higher force to separate the two components and hence it has a much higher separation resistance. This confirms that the method according to the invention can be used to produce a stable rubber-plastic composite.