Composition for producing cast polyamides

1. A composition comprising:

a) at least one first lactam; and

b) at least one activator for the anionic polymerization of lactams, wherein the activator comprises a compound of the formula (I)

where R 1 is a second lactam wherein the at least one first lactam and the second lactam may be the same or different lactams.

2. The composition as claimed in claim 1 , wherein the activator comprises a compound of the formula (II)

3. The composition as claimed in claim 2 , wherein the at least one first lactam comprises a compound of the formula (III)

where R is an alkylene group having from 3 to 13 carbon atoms.

4. The composition as claimed in claim 2 , wherein the at least one first lactam is caprolactam.

5. The composition as claimed in claim 1 , wherein the at least one first lactam and the second lactam are each a compound of the formula (III)

where R is an alkylene group having from 3 to 13 carbon atoms.

6. The composition as claimed in claim 1 , further comprising at least one catalyst selected from the group consisting of lactam magnesium halide, alkali-metal aluminodilactamate, alkali: metal lactamate, and alkaline-earth-metal lactamate.

7. A process for producing cast polyamides from the composition as claimed in claim 1 , 2 or 6 , wherein the process comprises polymerizing the constituents at temperatures of 80 to 160° C. in the form of melt.

8. A process for producing cast polyamides, the process comprising casting the composition as claimed in claim 1 , 2 or 6 .

9. The composition as claimed in claim 1 , wherein the composition comprises:

a) 94.2 to 99.8 wt % of the at least one first lactam,

b) 0.2 to 0.8 wt % of the at least one activator, and

c) 0 to 5 wt % of at least one catalyst selected from the group consisting of lactam magnesium halide, alkali-metal aluminodilactamate, alkali-metal lactamate, and alkaline-earth-metal lactamate,

where the entirety of the constituents a) to c) is 100 wt %.

10. The composition as claimed in claim 1 , wherein the at least one first lactam is at least one of: caprolactam and laurolactam.

11. A composition comprising:

a) 94.2 wt % to 99.8 wt % of at least one first lactam;

b) 0.2 wt % to 0.8 wt % of at least one activator for the anionic polymerization of lactams, wherein the activator comprises a compound of the formula (I)

where R 1 is a second lactam; and

c) 0 to 5 wt % of at least one catalyst for the anionic polymerization of lactams,

wherein the at least one first lactam and the second lactam may be the same or different lactams where the entirety of the constituents a) to c) is 100 wt %.

12. The composition of claim 11 , wherein:

the at least one first lactam is caprolactam;

the activator is a compound of the formula (II)

and

the composition includes an amount of the catalyst, and the catalyst is sodium caprolactamate.