Broadening of percolation slope in conductive carbon black compositions with at least one non-conductive polymer
The present disclosure relates to thermoplastic electrostatic dissipative (ESD) composites. The disclosed compositions comprise a thermoplastic resin phase and a filler composition comprising a conductive carbon black and a non-conductive polymer, dispersed within the thermoplastic resin phase. Also disclosed are methods for the manufacture of the disclosed composites and articles of manufacture comprising same.
1. An electrostatic dissipative composite, comprising
(a) a continuous thermoplastic polymer phase; and
(b) at least one dispersed filler phase comprised of a filler composition, comprising
(i) a conductive carbon black; and
(ii) a non-conductive polymer wherein at least one non-conductive polymer is selected from the group consisting of one of a styrene-acrylonitrile copolymer and an ultra-high molecular weight polymer and mixtures thereof;
wherein the composite exhibits a surface resistivity in the range of from 10 6 ohm/sq to 10 9 ohm/sq;
wherein the composite exhibits a tolerance level in the range of from ±0.37 to ±1.0.
2. The electrostatic dissipative composite of claim 1 , wherein the continuous thermoplastic polymer phase comprises at least one polymer selected from the group consisting of polycarbonate and polybutylene terephthalate.
3. The electrostatic dissipative composite of claim 2 , wherein at least one polycarbonate is a bisphenol A polycarbonate.
4. The electrostatic dissipative composite of claim 1 , wherein the ultra-high molecular weight polymer is an ultra-high molecular weight polyethylene polymer.
5. The electrostatic dissipative composite of claim 1 , wherein the styrene-acrylonitrile copolymer is a styrene-acrylonitrile copolymer encapsulated polytetrafluoroethylene.
6. The electrostatic dissipative composite of claim 1 , wherein the total amount of non-conductive polymer ranges from 15 to 25 weight % of the total filler loading.
7. An electrostatic dissipative composite, comprising
(a) a continuous thermoplastic polymer phase comprising at least one polymer selected from the group consisting of polybutylene terephthalate and polycarbonate; and
(b) at least one dispersed filler phase comprised of a filler composition, comprising
(i) a conductive carbon black; and
(ii) at least one non-conductive polymer selected from one of the group consisting of styrene-acrylonitrile copolymer encapsulated polytetrafluoroethylene and ultra-high molecular weight polyethylene polymer;
wherein the non-conductive polymer is present in an amount in the range of from 15 to 25 weight % relative to a total filler loading; and
wherein the composite exhibits a tolerance level in the range of from ±0.37 to ±1.0.