Composite materials comprising a reinforcing material and a star polyamide as a thermoplastic matrix, the precursor compound article of said materials and the products obtained using same

A precursor article of a composite material comprising a polymeric matrix and at least one reinforcing yarn and/or reinforcing fibers, said article comprising at least one reinforcing yarn and/or reinforcing fibers and at least one polymeric matrix yarn and/or polymeric matrix fibers, wherein:

• said reinforcing yarn and/or said reinforcing fibers are made of reinforcing material and optionally comprise a part made of thermoplastic polyamide,
• said polymeric matrix yarn and/or said polymeric matrix fibers are made of thermoplastic polyamide, and wherein:
• said thermoplastic polyamide of said reinforcing yarn and/or of said reinforcing fibers and/or of said polymeric matrix yarn and/or of said polymeric matrix fibers comprises at least one polyamide possessing a star structure comprising:
• star macromolecular chains comprising one or more cores and at least three polyamide branches or three polyamide segments bonded to a core, and
• optionally, linear polyamide macromolecular chains.

The article as claimed in claim 24, wherein said polyamide possessing a star structure is obtained by copolymerization of a mixture of monomers comprising at least:

• a) monomers of following general formula (1):
• b) monomers of following general formulae (IIa) and (IIb):
• c) and, optionally, monomers of following general formula (III):
• Z-R3-Z (III)
• wherein:
• R1 is an aliphatic or aromatic, cyclic or linear, hydrocarbonaceous radical comprising at least 2 carbon atoms which can comprise heteroatoms,
• A is a covalent bond or an aliphatic hydrocarbonaceous radical which can comprise heteroatoms and which comprises from 1 to 20 carbon atoms,
• Z represents a primary amine functional group or a carboxylic acid functional group, and
• Y is a primary amine functional group when X represents a carboxylic acid functional group,
• or
• Y is a carboxylic acid functional group when X represents a primary amine functional group,
• R2 and R3, which are identical or different, represent substituted or unsubstituted, aromatic, cycloaliphatic or aliphatic hydrocarbonaceous radicals comprising from 2 to 20 carbon atoms which can comprise heteroatoms, and m represents an integer between 3 and 8.