Transformation-stable composition comprising viscous polyamide, production thereof and use of same

Abstract

The use of at least one catalyst, at least one copper heat stabiliser and at least one oligo- or poly-carbodiimide with a matrix including at least one polyamide, in order to form a composition that has a good melt viscosity and is stable during transformation, in particular during extrusion.

1 . A viscous composition which is stable in transformation, the composition formed from at least one catalyst, of at least one copper-based heat stabilizer and of at least one oligo- or polycarbodiimide with a matrix comprising at least one polyamide, wherein the composition comprises, with respect to the total weight of the composition:
 a. 20.5 to 99.845% by weight of at least one polyamide;   b. 0.005 to 0.5% by weight of at least one catalyst;   c. 0.05 to 1% by weight of at least one copper-based heat stabilizer;   d. 0.1 to 3% by weight of at least one oligo- or polycarbodiimide;   e. 0 to 15% of at least plasticizer;   f. 0 to 30% of at least one polyolefin;   g. 0 to 30% of at least one additive.   
     
     
         2 . The composition as claimed in  claim 1 , wherein the composition consists of:
 a. 64.5 to 98.745% by weight of the at least one polyamide;   b. 0.005 to 0.5% by weight of at least one catalyst;   c. 0.05 to 1% by weight of at least one copper-based heat stabilizer;   d. 0.1 to 3% by weight of at least one oligo- or polycarbodiimide;   e. 1 to 30% of at least one polyolefin;   f. 0.1 to 1% of at least one additive.   
     
     
         3 . The composition as claimed in  claim 1 , wherein the composition consists of:
 a. 49.50 to 97.745% by weight of the at least one polyamide;   b. 0.005 to 0.5% by weight of at least one catalyst;   c. 0.05 to 1% by weight of at least one copper-based heat stabilizer;   d. 0.1 to 3% by weight of at least one oligo- or polycarbodiimide;   e. 1 to 15% of at least plasticizer;   f. 1 to 30% of at least one polyolefin;   g. 0.1 to 1% of at least one additive.   
     
     
         4 . The composition as claimed in  claim 1 , wherein the polyamide is chosen from an aliphatic polyamide, a cycloaliphatic polyamide, an aromatic polyamide or a mixture of these. 
     
     
         5 . The composition as claimed in  claim 1 , wherein the polyamide exhibits a M.P. comprised of 160° C. to 290° C., determined according to the standard ISO 11357-3 (2013). 
     
     
         6 . The composition as claimed in  claim 1 , wherein the polyamide is chosen from: PA 11, PA 12, 11/10.T, PA 10.10, PA 10.12 and the copolyamides 11/12 having either more than 90% of units 11 or more than 90% of units 12. 
     
     
         7 . The composition as claimed in  claim 1 , wherein the catalyst is chosen from phosphoric acid (H 3 PO 4 ), phosphorous acid (H 3 PO 3 ), hypophosphorous acid (H 3 PO 2 ) or a mixture of these. 
     
     
         8 . The composition as claimed in  claim 1 , wherein the copper-based heat stabilizer is a mixture of potassium iodide and copper iodide. 
     
     
         9 . The composition as claimed in  claim 1 , wherein the oligo- or polycarbodiimide is chosen from a Stabilizer, a Stabaxol®, or a mixture of these. 
     
     
         10 . A structure comprising the composition as defined in  claim 1 , wherein structure is selected from:
 a flexible pipe configured for the transportation of gas or for the exploitation of offshore oil deposits,   a flexible pipe for motor vehicles,   a hollow body, a molding or a sports item.   
     
     
         11 . The structure as claimed in  claim 10 , wherein the structure is a flexible pipe configured for the transportation of gas or for the exploitation of offshore oil deposits, wherein the structure exhibits a good resistance to thermal oxidation and a resistance to hydrolysis. 
     
     
         12 . The structure as claimed in  claim 10 , wherein the structure is a flexible pipe configured for the transportation of gas or for the exploitation of offshore oil deposits, wherein the flexible pipe exhibits a working temperature of at least 70° C. for 20 years. 
     
     
         13 . The structure as claimed in  claim 10 , wherein the composition consists of:
 a. 64.5 to 98.745% by weight of the at least one polyamide;   b. 0.005 to 0.5% by weight of at least one catalyst;   c. 0.05 to 1% by weight of at least one copper-based heat stabilizer;   d. 0.1 to 3% by weight of at least one oligo- or polycarbodiimide;   e. 1 to 30% of at least one polyolefin;   f. 0.1 to 1% of at least one additive, and   
       wherein the structure is a pipe is configured for the transportation of gas. 
     
     
         14 . The structure as claimed in  claim 10 , wherein the composition consists of:
 a. 49.50 to 97.745% by weight of the at least one polyamide;   b. 0.005 to 0.5% by weight of at least one catalyst;   c. 0.05 to 1% by weight of at least one copper-based heat stabilizer;   d. 0.1 to 3% by weight of at least one oligo- or polycarbodiimide;   e. 1 to 15% of at least plasticizer;   f. 1 to 30% of at least one polyolefin;   g. 0.1 to 1% of at least one additive, and   
       wherein the structure is a flexible pipe configured for the exploitation of offshore oil deposits. 
     
     
         15 . The structure as claimed in  claim 10 , wherein the composition consists of:
 a. 49.50 to 97.745% by weight of the at least one polyamide;   b. 0.005 to 0.5% by weight of at least one catalyst;   c. 0.05 to 1% by weight of at least one copper-based heat stabilizer;   d. 0.1 to 3% by weight of at least one oligo- or polycarbodiimide;   e. 1 to 15% of at least plasticizer;   f. 1 to 30% of at least one polyolefin;   g. 0.1 to 1% of at least one additive, and   
       wherein the structure is a flexible pipe for motor vehicles. 
     
     
         16 . A flexible pipe configured for the transportation of gas or for the exploitation of offshore oil deposits, or for motor vehicles, in particular for the transportation of fuel (gasoline, diesel, biodiesel or ethanol), for refrigeration, for air conditioning or for supplying with air, the flexible pipe comprising at least one layer of a composition as defined in  claim 1 . 
     
     
         17 . The flexible pipe as claimed in  claim 16 , wherein said layer is the layer in contact with the fluid and configured for the transportation of gas, wherein the composition consists of:
 a. 64.5 to 98.745% by weight of the at least one polyamide;   b. 0.005 to 0.5% by weight of at least one catalyst;   c. 0.05 to 1% by weight of at least one copper-based heat stabilizer;   d. 0.1 to 3% by weight of at least one oligo- or polycarbodiimide;   e. 1 to 30% of at least one polyolefin;   f. 0.1 to 1% of at least one additive.   
     
     
         18 . The flexible pipe as claimed in  claim 17 , wherein the flexible pipe comprises at least one second layer made of thermoplastic. 
     
     
         19 . The flexible pipe as claimed in  claim 16 , wherein said layer is the internal layer of a flexible pipe configured for the exploitation of offshore oil deposits and wherein the composition consists of:
 a. 49.50 to 97.745% by weight of the at least one polyamide;   b. 0.005 to 0.5% by weight of at least one catalyst;   c. 0.05 to 1% by weight of at least one copper-based heat stabilizer;   d. 0.1 to 3% by weight of at least one oligo- or polycarbodiimide;   e. 1 to 15% of at least plasticizer;   f. 1 to 30% of at least one polyolefin;   g. 0.1 to 1% of at least one additive.   
     
     
         20 . The flexible pipe as claimed in  claim 16 , wherein said layer is the external layer of a flexible pipe configured for the exploitation of offshore oil deposits and wherein the composition consists of:
 a. 49.50 to 97.745% by weight of the at least one polyamide;   b. 0.005 to 0.5% by weight of at least one catalyst;   c. 0.05 to 1% by weight of at least one copper-based heat stabilizer;   d. 0.1 to 3% by weight of at least one oligo- or polycarbodiimide;   e. 1 to 15% of at least plasticizer;   f. 1 to 30% of at least one polyolefin;   g. 0.1 to 1% of at least one additive.   
     
     
         21 . The flexible pipe as claimed in  claim 16 , wherein the pipe comprises an internal layer and an external layer, each of which consist of a composition wherein the composition consists of:
 a. 49.50 to 97.745% by weight of the at least one polyamide;   b. 0.005 to 0.5% by weight of at least one catalyst;   c. 0.05 to 1% by weight of at least one copper-based heat stabilizer;   d. 0.1 to 3% by weight of at least one oligo- or polycarbodiimide;   e. 1 to 15% of at least plasticizer;   f. 1 to 30% of at least one polyolefin;   g. 0.1 to 1% of at least one additive.