Method for synthesizing polyaryletherketones
View Patent ↗The invention relates to polyaryl ether ketones with low contents of residual materials, whether they are residual monomers or solvents of the synthetic process.
1. A polyaryl ether ketone with a residual solvent content of less than 100 ppm and a residual aromatic ether content of less than 1%, wherein the residual solvent has a water solubility of less than 0.05% at 25° C., wherein the polyaryl ether ketone is free from any residual alcohol.
2. The polyaryl ether ketone of claim 1 , wherein the residual aromatic ether has a molar mass less than 500 g·mol −1 .
3. The polyaryl ether ketone of claim 1 , wherein the polyaryl ether ketone has a thermal stability inducing less than 2% of variation in the viscosity measured according to standard ISO 307.
4. The polyaryl ether ketone of claim 1 , wherein the polyaryl ether ketone is a polyether ketone ketone (PEKK).
5. The polyaryl ether ketone of claim 4 , wherein the residual aromatic ether is 1,4-bis(4-phenoxybenzoyl)benzene.
6. The polyaryl ether ketone of claim 2 , wherein the residual solvent is ortho-dichlorobenzene.
7. A polyaryl ether ketone obtained by a process which comprises the following consecutive steps:
a) placing one or more aromatic acid chlorides and one or more aromatic ethers in contact with a Lewis acid in a solvent which has a water solubility of less than 0.05% at 25° C. at a temperature of between −5 and +25° C., with stirring;
b) carrying out a polymerization of the aromatic acid chlorides and aromatic ethers and completing the polymerization at a temperature of between 50 and 120° C. to provide a reaction mixture which includes a polyaryl ether ketone;
c) placing the reaction mixture in contact with water in the absence of alcohol with stirring in the optional presence of acid to extract the Lewis acid, forming a mixture of polyaryl ether ketone and liquid effluents;
d) separating the polyaryl ether ketone from the liquid effluents;
e) performing azeotropic distillation on the polyaryl ether ketone so as to eliminate residual solvent;
f) washing the polyaryl ether ketone; and
g) drying the polyaryl ether ketone at a temperature above Tg+20° C.;
wherein the polyaryl ether ketone has a residual solvent content of less than 100 ppm and a residual aromatic ether content of less than 1%.
8. The polyaryl ether ketone of claim 7 , wherein the polyaryl ether ketone has a thermal stability inducing less than 2% of variation in the viscosity measured according to standard ISO 307.
9. The polyaryl ether ketone of claim 7 , wherein the polyaryl ether ketone is a polyether ketone ketone (PEKK).
10. The polyaryl ether ketone of claim 9 , wherein the residual aromatic ether is 1,4-bis(4-phenoxybenzoyl)benzene.
11. The polyaryl ether ketone of claim 7 , wherein the residual solvent is ortho-dichlorobenzene.
12. The polyaryl ether ketone of claim 7 , wherein the polyaryl ether ketone is free from any residual alcohol.