Process for the anionic polymerization of lactams

2 Process according to claim 1, in which the product from stage (a1) is in the solid form.

3 Process according to either one of the preceding claims, in which molten lactam not comprising the mixture of catalyst and of regulator is also introduced in stage (b).

4 Process according to any one of the preceding claims, in which the polymerization of the lactam is carried out in the presence of one or more polymers (A) which is/are introduced either into the solution (a) or into the mixing device of stage (b) or into the molten lactam which is added in addition to that of (a) or according to any combination of these possibilities.

5 Process according to any one of the preceding claims, in which the polymerization of the lactam is carried out in the presence of one or more fillers which is/are introduced either into the solution (a) or into the mixing device of stage (b) or into the molten lactam which is added in addition to that of (a) or according to any combination of these possibilities.

7 Process according to claim 6, in which molten lactam comprising neither catalyst nor regulator is added in stage (b1), in addition to that from any one of stages (a1), (a2) or (a3), and this molten lactam is optionally blended in line with that originating from any one of stages (a1), (a2) or (a3), before introduction into the mould.

8 Process according to claim 6 or 7 in which the polymerization of the lactam is carried out in the presence of one or more polymers (A) which is/are introduced either into the solution from stage (a) or into the mould or into the molten lactam which is added in addition to that originating from any one of stages (a1), (a2) or (a3) or alternatively during the in line blending of the lactam originating from any one of stages (a1), (a2) or (a3) and of the lactam added in addition to that of (a) or a combination of all these possibilities.

9 Process according to any one of claims 6 to 8, in which the polymerization of the lactam is carried out in the presence of one or more fillers which is/are introduced either into the solution from stage (a) or into the mould or into the moltent lactam which is added in addition to that originating from any one of stages (a1), (a2) or (a3) or alternatively during the in line blending of the lactam originating from any one of stages (a1), (a2) or (a3) and of the lactam added in addition to that originating from any one of stages (a1), (a2) or (a3) or a combination of all these possibilities.

10 Process according to any one of the preceding claims, in which the catalyst is chosen from sodium, potassium, alkali metal hydrides, alkali metal hydroxides or alkali metal alkoxides, such as sodium methoxide or ethoxide.

11 Process according to any one of the preceding claims, in which the regulator is chosen from acetanilide, benzanilide, N-methylacetamide, N-ethylacetamide, N-methylformamide, (4-ethoxyphenyl)acetamide and alkylenebisamides, such as ethylenebisstearamide (EBS) and ethylenebisoleamide.

12 Process according to any one of the preceding claims, in which the ratio of the catalyst to the regulator, in moles, is between 0.5 and 2 and preferably between 0.8 and 1.2, the number of moles of regulator being expressed as the number of moles of amide groups.

13 Process according to any one of the preceding claims, in which the proportion of catalyst in the lactam in stage (b1) is between 0.1 and 5 mol per 100 mol of lactam and preferably between 0.3 and 1.5.

14 Process according to any one of the preceding claims, in which the lactam is lauryllactam, the temperature of stage (a3) is between 155 and 180° C. and preferably between 160 and 170° C., and the temperature of stage (b) or (b1) is between 200 and 350° C. and preferably between 230 and 300° C.

15 Process according to any one of the preceding claims, in which the catalyst is replaced totally or in part by a lactamate.

16 Lactam in the solid form

• comprising (i) a catalyst capable of creating a lactamate and (ii) a regulator chosen from amides of formula R1-NH—CO—R2, in which R1 can be substituted by an R3-CO—NH— or R3-O— radical and in which R1, R2 and R3 denote an aryl, alkyl or cycloalkyl radical,
• it being possible for this solid form to be divided.

17 Lactam according to claim 16 in which the catalyst is replaced totally or in part by a lactamate.