Reinforced polyamide composition
A polyamide modified by a compound including at least one hydroxyl group, as well as a method for preparing said polyamide and articles obtained from the modified polyamide are described. A polyamide composition including reinforcing fillers, and a modified polyamide obtained by polymerization from, in particular, a monofunctional hydroxyaromatic acid or amino acid compound in the presence of diacid, diamine and/or amino acid or lactam compounds are also described.
1. A composition comprising reinforcing fillers and a polyamide modified by a compound comprising at least one aromatic hydroxyl group chemically bonded to the chain of the polyamide, the polyamide being obtained by polymerization of the following monomers:
i) a hydroxyaromatic monoamine (A4) having:
at least 3 carbon atoms separating the nitrogen atom of the amine functional group from the oxygen atom of the hydroxyl functional group, when two amine and hydroxyl functional groups are attached to a carbon atom forming part of an aromatic ring, and
at least 5 carbon atoms separating the nitrogen atom of the amine functional group from the oxygen atom of the hydroxyl functional group in the other cases, and
ii) at least one polyamide monomer selected from the group consisting of:
a mixture of an aliphatic, cycloaliphatic, arylaliphatic or aromatic diacid B) and of a diamine C), and/or
a lactam or an amino acid D).
2. The composition as claimed in claim 1 , wherein the modified polyamide is obtained by polymerization of the following monomers:
A) a hydroxyaromatic monoamine (A4),
B) an aliphatic, cycloaliphatic, arylaliphatic or aromatic diacid,
C) a diamine, and
D) optionally a lactam or an amino acid.
3. A composition comprising reinforcing fillers and a polyamide modified by a compound comprising at least one aromatic hydroxyl group chemically bonded to the chain of the polyamide, the polyamide being obtained by polymerization of the following monomers:
i) 4-hydroxyphenylacetic acid or tyramine, and
ii) at least one polyamide monomer selected from the group consisting of:
a mixture of an aliphatic, cycloaliphatic, arylaliphatic or aromatic diacid B) and of a diamine C), and/or
a lactam or an amino acid D).
4. The composition as claimed in claim 1 , wherein the compound B) is of following formula (V):
HOOC—R′—COOH (V)
in which R′ is a divalent aliphatic, cycloaliphatic, arylaliphatic or aromatic hydrocarbon radical.
5. The composition as claimed in claim 4 , wherein the R′ radical comprises between 2 and 18 carbon atoms.
6. The composition as claimed in claim 4 , wherein the compound B) is an aliphatic diacid.
7. The composition as claimed in claim 1 , wherein the compound C) is of following formula (VI):
H 2 N—R—NH 2 (VI)
in which R is a divalent aliphatic, cycloaliphatic, arylaliphatic or aromatic hydrocarbon radical.
8. The composition as claimed in claim 7 , wherein the R radical comprises between 2 and 18 carbon atoms.
9. The composition as claimed in claim 1 , wherein the lactam or amino acid D) comprises between 2 and 18 carbon atoms.
10. The composition as claimed in claim 1 , wherein the reinforcing fillers are fibrous reinforcing fillers selected from the group consisting of glass fibers, carbon fibers, natural fibers, aramid fibers and nanotubes.
11. The composition as claimed in claim 1 , wherein the reinforcing fillers are nonfibrous reinforcing fillers selected from the group consisting of alumina, carbon black, aluminosilicate clays, montmorillonites, zirconium phosphate, kaolin, calcium carbonate, diatomaceous earths, graphite, mica, silica, titanium dioxide, zeolites, talc and wollastonite.
12. The composition as claimed in claim 1 , wherein said composition comprises between 1% and 60% by weight of reinforcing filler, with respect to the total weight of the composition.
13. The composition as claimed in claim 1 , wherein said composition further comprises agents which modify the impact strength.
14. A process for the preparation of a composition as claimed in claim 1 , said process comprising forming the modified polyamide by melt polymerizing the hydroxyaromatic monoamine (A4) in the presence of the monomers B) and C) and/or D) and blending the modified polyamide with reinforcing fillers.
15. An article obtained by forming from the composition as claimed in claim 1 , by molding.
16. The composition as claimed in claim 2 , wherein the diamine is an aliphatic diamine.
17. The composition as claimed in claim 2 , wherein the optional lactam or amino acid is an aliphatic lactam or amino acid.
18. The composition as claimed in claim 10 , wherein the nanotubes are carbon nanotubes.
19. The article of claim 15 , wherein molding is selected from the group consisting of injection molding, injection/blow molding, extrusion/blow molding and extrusion molding.
20. The composition as claimed in claim 3 , wherein the modified polyamide is obtained by polymerization of the following monomers:
A) the 4-hydroxyphenylacetic acid or the tyramine,
B) an aliphatic, cycloaliphatic, arylaliphatic or aromatic diacid,
C) a diamine, and
D) optionally a lactam or an amino acid.
21. The composition as claimed in claim 3 , wherein the compound B) is of following formula (V):
HOOC—R′—COOH (V)
in which R′ is a divalent aliphatic, cycloaliphatic, arylaliphatic or aromatic hydrocarbon radical.
22. The composition as claimed in claim 4 , wherein the R′ radical comprises between 2 and 18 carbon atoms.
23. The composition as claimed in claim 4 , wherein the compound B) is an aliphatic diacid.
24. The composition as claimed in claim 4 , wherein the compound C) is of following formula (VI):
H 2 N—R—NH 2 (VI)
in which R is a divalent aliphatic, cycloaliphatic, arylaliphatic or aromatic hydrocarbon radical.
25. The composition as claimed in claim 9 , wherein the R radical comprises between 2 and 18 carbon atoms.
26. The composition as claimed in claim 4 , wherein the lactam or amino acid D) comprises between 2 and 18 carbon atoms.
27. The composition as claimed in claim 21 , wherein the reinforcing fillers are fibrous reinforcing fillers selected from the group consisting of glass fibers, carbon fibers, natural fibers, aramid fibers and nanotubes.
28. The composition as claimed in claim 21 , wherein the reinforcing fillers are nonfibrous reinforcing fillers selected from the group consisting of alumina, carbon black, aluminosilicate clays, montmorillonites, zirconium phosphate, kaolin, calcium carbonate, diatomaceous earths, graphite, mica, silica, titanium dioxide, zeolites, talc and wollastonite.
29. The composition as claimed in claim 21 , wherein said composition comprises between 1% and 60% by weight of reinforcing filler, with respect to the total weight of the composition.
30. The composition as claimed in claim 21 , wherein said composition further comprises agents which modify the impact strength.
31. A process for the preparation of a composition as claimed in claim 21 , said process comprising forming the modified polyamide by melt polymerizing the tyramine in the presence of the monomers B) and C) and/or D) and blending the modified polyamide with reinforcing fillers.
32. An article obtained by forming from the composition as claimed in claim 21 , by molding.
33. The composition as claimed in claim 20 , wherein the diamine is an aliphatic diamine.
34. The composition as claimed in claim 20 , wherein the optional lactam or amino acid is an aliphatic lactam or amino acid.
35. The composition as claimed in claim 27 , wherein the nanotubes are carbon nanotubes.
36. The article of claim 32 , wherein molding is selected from the group consisting of injection molding, injection/blow molding, extrusion/blow molding and extrusion molding.