Thermoplastic composition made of polyphenylene sulphide and polyamide-grafted polyolefin
The present invention relates to a composition that comprises a mixture of polymers, which comprises: a first polymer comprising polyphenylene sulphide, making up 55 wt % to 95 wt % of the mixture; a thermoplastic modifier, making up 5 wt % to 45 wt % of the mixture; optionally one or more functional additives, making up at most 10 wt % of the mixture, preferably at most 5 wt % of the mixture, characterised in that the thermoplastic modifier includes a second polymer which comprises a polyolefin backbone containing a group of at least one unsaturated monomer (X) and a plurality of polyamide grafts. The invention also relates to a multilayer structure including a plurality of adjacent layers, at least one of which consists of the aforementioned composition.
1. A thermoplastic composition consisting of a mixture of polymers, consisting of:
a first polymer consisting of polyphenylene sulfide, present between 55% and 95% by weight of the mixture;
a thermoplastic modifier, present between 5% and 45% by weight of the mixture; and
optionally one or more functional adjuvants, present at most at 10% by weight of the mixture,
wherein the thermoplastic modifier comprises a second polymer consisting of a polyolefin backbone containing at least one unsaturated monomer (X) and a plurality of polyamide grafts, wherein the polyamide grafts are attached to the polyolefin backbone by the residue of the unsaturated monomer (X) comprising a function that can react by a condensation reaction with a polyamide having at least one amine end and/or at least one carboxylic acid end, the residue of the unsaturated monomer (X) is bound to the backbone by grafting or copolymerization.
2. The composition of claim 1 , wherein the thermoplastic modifier further comprises a third polymer consisting of one or more polyolefins.
3. The composition of claim 2 , wherein the second and third polymers are each present in the thermoplastic modifier between 5% and 95% by weight of said thermoplastic modifier, and wherein the sum of the second and third polymers constitutes 100% of the thermoplastic modifier.
4. The composition of claim 2 , wherein the thermoplastic modifier consists of the second and third polymers.
5. The composition of claim 1 , wherein the thermoplastic modifier represents from between 10% and 30% by weight of the mixture.
6. The composition of claim 1 , wherein the grafted polymers nanostructured.
7. The composition of claim 1 , wherein the average molar weight of the polyamide grafts of the grafted polymer is in the range from 1000 to 10,000 g/mol.
8. The composition of claim 1 , wherein the polyamide grafts comprise at least one copolyamide.
9. The composition of claim 1 , wherein the functional adjuvant consists of one or more plasticizers, adhesion promoters, UV stabilizers and/or UV absorbers, antioxidants, flame retardants, colorants/optical brighteners, pigments and strengthening fillers.
10. A multilayer structure including a plurality of adjacent layers, wherein at least one of the plurality of adjacent layers consists of the composition of claim 1 .
11. The composition of claim 8 , wherein the at least one copolyamide is 6/12 mono NH 2 , and/or a monofunctional NH 2 polyamide 6 and/or a monofunctional NH 2 polyamide 11.
12. The multilayer structure of claim 10 in the form of a coating for a cable or a tube.