PROCESS FOR THE PRODUCTION OF POLYAMIDES

摘要

The invention relates to process for the production of a PA-MXDT/ZT polyamide comprising the following steps: (i) providing a solid MXDT/ZT salt, wherein MXD is meta-xylylenediamine, T is terephthalic acid, Z is a linear aliphatic diamine having from 2 to 12 carbon atoms and wherein the amount of Z is from 0to40 mole %with respect to the total of the amount of MXD and Z units in the polymer, (ii) solid state polymerizing the MXDT/ZT salt to obtain the polyamide, wherein the solid state polymerizationis carried out at least partly under a diamine atmosphere. The invention further relates to a PA-MXDT/ZT polyamide, wherein the polymer has a glass transition temperature fulfilling the following relation: Tg > 226–475*Y, wherein Y is the weight ratio g/g of all CH2 groups in the polymer with respect to the total weight of the polyamide.