Articles comprising a polyolefin-based element joined to a polyamide-based element, and process for obtaining them
The invention concerns manufactured articles comprising at least two assembled thermoplastic elements, a first element based on polyolefin and a second element based on polyamide. The elements are assembled by being welded together.
1. A process for manufacturing articles by forming elements made of a thermoplastic and then joining them together, wherein the joining operation is carried out by bringing the elements into contact with each other over at least a portion of their surfaces and then welding the two elements over at least a portion where the two elements are in contact, at a temperature above the softening point of the materials constituting the elements, a first element being formed from a material based on a polyolefin and a second element being formed from a material comprising a polyamide, wherein the material of the second element is a composition comprising at least one polyamide and a compatibilizer for polyamides and polyolefins.
2. The process as claimed in claim 1 , wherein the welding is carried out by means of a laser.
3. The process as claimed in claim 1 , wherein the welding is carried out by a vibration welding technique.
4. The process as claimed in claim 1 , wherein the welding is carried out by an ultrasonic welding technique.
5. The process as claimed in claim 1 , wherein the welding is carried out by a hot-plate welding technique.
6. The process as claimed in claim 1 , wherein the welding is carried out by an infrared welding technique.
7. The process as claimed in claim 1 , wherein the compatibilizer is an ionomer.
8. The process as claimed in claim 1 , wherein the material of the second element is a composition comprising a polyamide, an ionomer and a polyolefinic compound.
9. The process as claimed in claim 8 , wherein the polyolefinic compound is an elastomer or a thermoplastic.
10. The process as claimed in claim 8 , wherein the polyolefinic compound is a thermoplastic of the same kind as that from which the first element is produced.
11. The process as claimed in claim 1 , wherein the polyamide is selected from the group consisting of nylon-6, nylon-11, nylon-12, nylon-4,6, nylon-6,10, nylon-6,6, nylon-6,10, nylon-6,36, copolymers and blends based on these polymers.
12. The process as claimed in claim 1 , wherein the composition has a melt flow index of between 0.5 g/10 min and 8 g/10 min, measured under a load of 5 kg at a temperature of 275° C.
13. The process as claimed in claim 1 , wherein the polyolefin is selected from the group consisting of polyethylenes, polypropylenes, copolymers and blends based on these polymers.
14. The process as claimed in claim 8 , wherein the polyolefinic compound is polyethylene.
15. The process as claimed in claim 8 , wherein the polyolefinic compound is an ethylene-propylene rubber functionalized by maleic anhydride.
16. The process as claimed in claim 8 , wherein the composition has a continuous phase and a dispersed phase within the continuous phase, the continuous phase comprising the polyamide and the dispersed phase comprising the polyolefinic compound.
17. The process as claimed in claim 1 , wherein the elements are obtained by using a technique selected from the group consisting of injection molding, extrusion blow molding, gas injection molding and water injection molding.
18. The process as claimed in claim 1 , wherein the two elements are hollow, assembled by the complementarity of the shapes so that the hollow portions of each of the elements communicate with each other.
19. The process as claimed in claim 18 , wherein the second element is a tubular conduit.