CROSSLINKABLE POLYMER COMPOSITION AND CROSSLINKED POLYMER COMPOSITION

Abstract

The invention relates to a crosslinkable polymer composition (1), comprising a crosslinkable polymer material (2), particularly a polyolefin, preferably a polyethylene, additives (3), a first initiator (4) and a second initiator (5), wherein said first initiator (4) and second initiator (5) are different.

Claims

1.-10. (canceled)

11. A crosslinkable polymeric composition, comprising: a crosslinkable polymeric material; additives; a first initiator; and a second initiator; wherein the first initiator and the second initiator are different.

12. The crosslinkable polymeric composition according to claim 11, wherein the first initiator and the second initiator are selected from the group consisting of peroxides, photoinitiators, azo compounds and combinations thereof.

13. The crosslinkable polymeric composition according to claim 11, wherein the first initiator and the second initiator have different activation energies.

14. The crosslinkable polymeric composition according to claim 11, wherein the first initiator and the second initiator are present in different amounts.

15. The crosslinkable polymeric composition according to claim 11, wherein, if the first initiator and the second initiator are peroxides, the first initiator has a lower light-off temperature than the second initiator.

16. The crosslinkable polymeric composition according to claim 11, wherein the polymeric material is a polyolefin having a density according to DIN EN ISO 1183 of 0.90 to 0.960 g/cm.sup.3 and with an MFR according to DIN EN ISO 1133 at 190 C./21.6 kg of 2 to 40 g/10min.

17. The crosslinkable polymeric composition according to claim 11, wherein the additives are selected from the group consisting of stabilizers, fillers, lubricants, flow aids, antistatic agents, pigments, method auxiliaries, polymers and combinations thereof.

18. The crosslinked polymeric composition according to claim 11, wherein the degree of crosslinking according to DIN EN ISO 10147 is between 70% and 95%.

19. A method for crosslinking the crosslinkable polymeric composition according to claim 11, wherein the crosslinkable polymeric composition is crosslinked in a first step, wherein a viscosity of the crosslinked crosslinkable polymeric composition is greater than that of the crosslinkable polymeric composition, wherein the crosslinked crosslinkable polymeric composition is formed to form a formed crosslinked crosslinkable polymeric composition, and is then formed in a second step from the formed crosslinkable crosslinkable polymeric composition by crosslinking the crosslinked polymeric composition.

20. A molded part of the crosslinked polymeric composition according to claim 18.

Description

[0073] The present invention will be described in detail with reference to the accompanying drawing, wherein:

[0074] FIG. 1 shows a schematic representation of the crosslinking method and the forming of a crosslinkable polymeric composition to a crosslinked polymeric composition.

[0075] FIG. 1 shows, in a schematic representation, the crosslinking method and the forming of the crosslinkable polymeric composition 1.

[0076] The crosslinkable polymeric composition 1 is shown in FIG. 1 as an oval on the left side, wherein this is intended to symbolize that the crosslinkable polymeric composition 1 is unformed.

[0077] Additives 3 are contained in the crosslinkable polymeric composition 1, for example in the form of thermal and/or light stabilizers.

[0078] Polyethylene 2 is contained as the crosslinkable polymeric material in the crosslinkable polymeric composition 1.

[0079] Furthermore, the crosslinkable polymeric composition 1 comprises a first initiator 4 and a second initiator 5.

[0080] A shaped crosslinked crosslinkable polymeric composition 1 is prepared from the crosslinkable polymeric composition 1 in a first step A.

[0081] The first step A comprises the crosslinking and forming of the crosslinkable polymer composition 1.

[0082] In crosslinking of the crosslinkable polymeric composition 1 in the first step A, the first initiator 4 in the crosslinkable polymeric composition 1 reacts and crosslinks the crosslinkable polymeric material 2, in this case polyethylene.

[0083] Forming to the formed crosslinked crosslinkable polymeric composition 8 can take place by virtue of the higher viscosity of the crosslinked crosslinkable polymeric composition compared with that of the crosslinkable polymeric composition 1.

[0084] In FIG. 1, this is illustrated by a star-shaped configuration of the formed crosslinked crosslinkable polymeric composition 8.

[0085] Additives 3 are contained in the formed crosslinked crosslinkable polymeric composition 8, namely the above-described thermal and/or light stabilizers, in addition to further crosslinkable polymeric material 2, in this case in the form of polyethylene.

[0086] The first initiator 4 is no longer present in the formed crosslinked crosslinkable polymeric composition 8.

[0087] The formed crosslinked crosslinkable polymeric composition 8 still has the second initiator 5.

[0088] In a second step B, the molded part 10 is prepared from the formed crosslinked crosslinkable polymeric composition 8without causing any further change in formby final crosslinking of the formed crosslinked crosslinkable polymeric composition 8 to the crosslinked polymeric composition 9.

[0089] In this case, the second initiator 5 is consumed and thus no longer exists in the crosslinked polymeric composition 9.

[0090] The additives 3 are still present in the crosslinked polymeric composition 9.

[0091] The present invention has been described in detail with reference to the embodiment of the present invention shown in the figure. It is to be understood that the present invention is not limited to the illustrated embodiment, but to the scope of the claims of the present invention.

LIST OF REFERENCE NUMBERS

[0092] 1 crosslinkable polymeric composition

[0093] 2 crosslinkable polymeric material

[0094] 3 additives

[0095] 4 first initiator

[0096] 5 second initiator

[0097] 8 formed crosslinked crosslinkable polymeric composition

[0098] 9 crosslinked polymeric composition

[0099] 10 molded part

[0100] A Pre-crosslinking and forms of the crosslinkable polymeric composition

[0101] B final crosslinking of the formed crosslinked crosslinkable polymeric composition