Route for the synthesis of statistical, aliphatic-aromatic copolyamides, and the resulting statistical, aliphatic-aromatic copolyamides

Method for preparing an aliphatic-aromatic copolyamide of formula (I):

• where:
• p is an integer of between 5 and 11;
• n is the number average in number of aromatic units;
• And m is the number average in number of aliphatic units;
• Such that the ratio n/(n+m) is between 5 and 50%;
• /represents the statistical sequence of the aliphatic and aromatic units, said method comprising the reacting of:
• A lactam derivative of formula (II):
• and/or one of the salts thereof,
• where p is defined as in formula (I);
• An alkyl 4-aminobenzoate of formula (III):
• either in free form, in which case a strong base is added to the reaction mixture, or in the form of one of the salts thereof of formula (III′):
• where:
• R is a linear or branched C1-C6 alkyl group;
• and
• X+is an alkali metal cation, or magnesium halide ion (MgHal+), or a phosphazenium ion (such as alkyl phosphazenium, in particular tBuP4H+);
• And:
• An activator.