Composite materials comprising conductive nano-fillers

1. A process for the production of a curable composition, comprising:

forming a first composition comprising one or more conductive nano-filler(s) coated or wrapped with one or more macro-molecules of one or more polyarylethersulphone thermoplastic polymer(s) (A); and

mixing or dispersing the first composition with or into a second composition comprising one or more uncured thermoset resin precursor(s) (P), and optionally one or more curing agent(s) therefor,

wherein the first composition does not comprise an uncured thermoset resin precursor.

2. A process according to claim 1 wherein said first composition comprises said conductive nano-filler (CNF) in an amount such that the mass fraction w(CNF) is from about 1% to about 20%, wherein w(CNF) is calculated as:

w (CNF)= m (CNF)/( m ( A )+ m (CNF))

where m(CNF) is the mass of conductive nano-filler in said first composition, and m(A) is the mass of the thermoplastic polymer (A) in said first composition, and

wherein the amount of thermoplastic polymer (A) combined with the resin precursor is such that the mass fraction w(A), calculated as w(A)=m(A)/m, where m(A) is the mass of the thermoplastic polymer (A) present in the cured thermoset resin composition having the mass m, is from 0.5% to 40%.

3. A process according to claim 1 , wherein said first composition is in micronized particulate form, and the micronized particulate exhibits an average particle size in the range of from about 10 to about 150 μm.

4. A process according to claim 1 , wherein said polyarylethersulphone thermoplastic polymer (A) comprises ether-linked repeating units, optionally further comprising thioether-linked repeating units, the units being selected from:

—[ArSO 2 Ar] n —

and optionally from:

—[Ar] a —

wherein:

Ar is phenylene;

n=1 to 2 and can be fractional;

when —[Ar] a — is present, a=1 to 3 and can be fractional and when a exceeds 1, said phenylene groups are linked linearly through a single chemical bond or a divalent group other than —SO 2 —, or are fused together,

provided that the repeating unit —[ArSO 2 Ar] n — is always present in the polyarylethersulphone in such a proportion that on average at least two of said —[ArSO 2 Ar] n — units are in sequence in each polymer chain present, and

wherein the polyarylethersulphone has one or more reactive pendant and/or end group(s).

5. A process according to claim 4 , wherein the repeating units in said polyarylethersulphones are:

—X—Ar—SO 2 —Ar—X—Ar—SO 2 —Ar—  (I):

and

—X—(Ar) a —X—Ar—SO 2 —Ar—  (II):

wherein:

X is O or S and may differ from unit to unit.

6. A process according to claim 5 , wherein said reactive pendant- and/or end-group(s) are selected from the group consisting of: OH, NH 2 , NHR b and —SH, wherein R b is a hydrocarbon group containing up to eight carbon atoms.

7. A process according to claim 1 , wherein the one or more conductive nano-filler(s) are carbon nano-tubes.

8. A process according to claim 1 , wherein the second composition further comprises one or more conductive nano-filler(s), and said conductive nano-filler(s) in the second composition are the same as or different to the conductive nano-filler(s) in the first composition.

9. A process according to claim 1 , wherein said thermoplastic polymer(s) is dissolved in said thermosetting resin precursor formulation.

10. A process according to claim 1 , wherein one or more curing agent(s) is/are present, and the curing agent(s) is/are added after the mixing of said one or more uncured thermoset resin precursor(s) (P) with the first composition.

11. A process according to claim 1 , wherein said thermosetting resin precursor(s) (P) is/are epoxy resin precursor(s).

12. A process according to claim 1 , wherein the forming of the first composition comprises conducting polymerisation of said thermoplastic polymer(s) (A) in the presence of the conductive nano-filler(s).

13. A process according to claim 1 , wherein the first composition is in the form of pellets, or particles, or fibers, which are formed by mixing one or more conductive nano-filler(s) and one or more polyarylethersulphone thermoplastic polymer(s) (A) in a screw extruder to form a mixture and extruding the mixture.

14. A process according to claim 1 , wherein said first composition is in the form of pellets, or particles, or continuous or chopped fibers.

15. A process according to claim 1 , wherein the thermoset resin precursor(s) is/are mono- or poly-glycidyl derivative(s) of one or more compounds selected from the group consisting of: aromatic diamines, aromatic monoprimary amines, aminophenols, polyhydric phenols, polyhydric alcohols, and polycarboxylic acids epoxy resin precursor(s).