Composite materials comprising conductive nano-fillers
A process for the production of a composition comprising one or more conductive nano-filler(s), one or more polyarylethersulphone thermoplastic polymer(s) (A), one or more uncured thermoset resin precursor(s) (P), and optionally one or more curing agent(s) therefor, wherein said process comprises mixing or dispersing a first composition comprising one or more conductive nano-filler(s) and one or more polyarylethersulphone thermoplastic polymer(s) (A) with or into one or more uncured thermoset resin precursor(s) (P), and optionally one or more curing agent(s) therefor.
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,
the one or more polyarylethersulphone thermoplastic polymer(s) comprise the repeating units:
—X—Ar—SO 2 —Ar—X—Ar—SO 2 —Ar— (I)
and
—X—(Ar) a —X—Ar—SO 2 —Ar— (II)
where
X is O or S and may differ from unit to unit, Ar is phenylene, a=1 to 3 and can be fractional, and
the polyarylethersulphone thermoplastic polymer(s) are dissolved in the thermoset resin precursor(s) when the first composition is mixed with or dispersed into the second composition.
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 the polyarylethersulphone thermoplastic polymer(s) comprise reactive pendant- and/or end-group(s) selected from: OH, NH 2 , NHR b and —SH, wherein R b is a hydrocarbon group containing up to eight carbon atoms.
4. A process according to claim 1 , wherein the one or more conductive nano-filler(s) are carbon nano-tubes.
5. A process according to claim 1 , wherein the second composition further comprises one or more polyarylethersulphone(s) and one or more conductive nano-filler(s).
6. 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.
7. A process according to claim 1 , wherein said thermoset resin precursor(s) (P) is/are epoxy resin precursor(s).
8. A process according to claim 1 , wherein the forming of the first composition comprises synthesizing said thermoplastic polymer(s) (A) in the presence of the conductive nano-filler(s).
9. A process according to claim 1 , wherein the thermoset resin precursor(s) is/are epoxy resin precursor(s) selected from:
(i) glycidyl ethers of bisphenol A, bisphenol F, dihydroxydiphenyl sulphone, dihydroxybenzophenone, and dihydroxy diphenyl;
(ii) epoxy resins based on Novolacs; and
(iii) glycidyl functional reaction products of m- or p-aminophenol, m- or p-phenylene diamine, 2,4-, 2,6- or 3,4-toluylene diamine, 3,3′- or 4,4′-diaminodiphenyl methane.