Claims
- 1. A process for the preparation of a composite tubular article consisting of an outer sheath of a vulcanized elastomer containing carboxylic acid or dicarboxcylic acid anhydride functional groups, used directly in combination with a tube of thermoplastic elastomer containing polyamide blocks having a melting point of between 120.degree. C. and 210.degree. C., the said article exhibiting a high peel strength of the vulcanized elastomer sheath when subjected to a separating stress, preferably higher than 2 daN/cm, comprising (a) sheathing a tubular thermoplastic elastomer containing polyamide blocks by extrusion at a temperature of between 50.degree. C. and 120.degree. C., with a vulcanizable elastomeric composition comprising a carboxylic acid or dicarboxcylic acid anhydride functional groups and a crosslinking system and optionally various adjuvants and fillers, and (b) vulcanizing said sheath, wherein said vulcanizing is completed in 15 minutes or less at a temperature between -5.degree. C. and +30.degree. C. relative to a Vicat point of said thermoplastic elastomer containing polyamide blocks.
- 2. The process for the preparation of a composite tubular article of claim 1, wherein said vulcanizable elastomeric composition is extruded into a sheathing die in which there is present a thermoplastic tube.
- 3. The process for the preparation of a composite tubular article of claim 1, wherein said vulcanizing is completed in a vulcanization autoclave for rubber that uses hot air and infrared to achieve vulcanization.
- 4. The process for the preparation of a composite tubular article of claim 1, wherein the tubular thermoplastic elastomer containing polyamide blocks further comprises fillers between 5 and 100 parts by weight per 100 parts of elastomers.
- 5. The process for the preparation of a composite tubular article of claim 1, wherein the vulcanization temperature is about at the Vicat point of the thermoplastic elastomer containing polyamide blocks.
- 6. The process for the preparation of a composite tubular article of claim 1, wherein said vulcanizing has a t.sub.90 of 15 minutes or less.
- 7. The process for the preparation of a composite tubular article of claim 1, wherein said vulcanizing has a t.sub.90 between 5 and 10 minutes.
- 8. The process for the preparation of a composite tubular article of claim 1, wherein said vulcanizing yields a torque increase of 0.3 Nm in between 4 and 6 minutes.
- 9. The process for the preparation of a composite tubular article of claim 1, wherein said tubular thermoplastic elastomer containing polyamide blocks further comprises an inner protective layer of polyamide with a melting point higher than 220.degree. C.
- 10. The process for the preparation of a composite tubular article of claim 9, wherein said inner protective layer of polyamide is a polyamide 6 or polyamide 66.
- 11. The process for the preparation of a composite tubular article of claim 1, wherein said vulcanization is carried out continuously by placing a UHF oven in line with a sheathing extruder.
- 12. The process for the preparation of a composite tubular article of claim 1, wherein said article exhibits a peel strength higher than 2 daN/cm.
Priority Claims (1)
Number |
Date |
Country |
Kind |
93 00226 |
Jan 1993 |
FRX |
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Parent Case Info
This application is a divisional, of Application Ser. No. 08/180,384, filed Jan. 12, 1994 now abandoned.
US Referenced Citations (9)
Foreign Referenced Citations (3)
Number |
Date |
Country |
0034294 |
Aug 1981 |
EPX |
58-124634 |
Jul 1983 |
JPX |
1-271229 |
Oct 1989 |
JPX |
Divisions (1)
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Number |
Date |
Country |
Parent |
180384 |
Jan 1994 |
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