Thermoplastically formable composite materials based on polyamide 12 matrix

A discontinuous process for producing shaped bodies of thermoplastically formable laminated composite materials of reinforcing fibers in a polyamide 12 matrix, comprising:

• a. providing a finely divided powder mixture of lactam 12 and amounts sufficient to effect conversion of lactam 12 to polyamide 12 of an activator and a catalyst, applying said finally divided powder to a fiber arrangement in the form of woven fabrics, mats, layments, knitted fabrics, non-woven fabrics, plaited fabrics, embroidered fabrics, cross-wise arranged rovings or combinations thereof in a mold or tool, and heating said powder mixture on said fiber arrangement under the effects of pressure and temperature to provide a lactam 12 melt on said fiber arrangement in the mold or tool;
• b. impregnating said fiber arrangement with said melt in the liquid state, and heating to a temperature of at least the melting point of polyamide 12 and not in excess of 300.degree. C.;
• whereby the lactam 12 forms the matrix for a shaped body;
• c. polymerizing said activated anionic lactam 12 melt under the effects of temperature and pressure in said mold or tool in such a way that the shape of said shaped body is achieved;
• and
• d. optionally reshaping said shaped body by subjecting said shaped body to an after-shaping step under the effects of pressure and temperature.

A process for producing a shaped body of a thermoplastically formable composite material made of reinforcing fibers in a polyamide 12 matrix, consisting essentially of

• (a) preparing an activated anionic lactam 12 melt,
• (b) injecting the lactam 12 melt into a fiber arrangement in a mold to impregnate said fiber arrangement with said lactam 12 melt, and increasing the temperature of the melt immediately after the reinforcing fibers have been impregnated, wherein the temperature is at about the melting point of the anionically polymerized matrix and not in excess of 300.degree. C., so that the melt forms the matrix for the shaped body,
• (c) carrying out final-polymerization of the activated lactam 12 melt under the effects of temperature and pressure in such a way that the shape is achieved, and
• (d) optionally after-shaping the shaped body under the effects of pressure and temperature.

A process for producing a shaped body of a thermoplastically formable composite material made of an arrangements of reinforcing fibers in a polyamide 12 matrix, consisting essentially of

• (a) applying a finely divided powder mixture of lactam 12 containing an activator and a catalyst in concentrations relevant to the process to the reinforcing fibers, and melting the powder mixture under the effects of pressure and temperature,
• (b) impregnating the melted mixture in the liquid state into the reinforcing fibers within a mold and starting polymerization, and increasing the temperature of the melt immediately after the fiber arrangement has been impregnated, wherein the temperature is increased above the melting point of the anionically polymerized matrix and not in excess of 300.degree. C., so that the melt forms the matrix for the shaped body,
• (c) carrying out final-polymerization of the activated lactam 12 melt under the effects of temperature and pressure in such a way that the shape is achieved, and
• (d) optionally subjecting the shaped body to an after-shaping step under the effects of pressure and temperature.