Former EnerG2 Executive Joins PolyDrop as Vice President of Research and Development
January 1, 2015
PolyDrop receives NSF SBIR Phase II Award
February 17, 2016
Intrinsically Conducting Polymers (ICPs)
February 1, 2015
Intrinsically conducting polymers (ICPs) are a unique class of polymers that arise from a slight, but crucial, difference in backbone chemistry with alternating double-single bond structures that reduce surface resistivity and therefore conductivity. On the downside, however, those alternating double-single bonds also greatly reduce the stability and processability of the ICPs.
This trade-off between conductivity and processability is prevalent not only in ICP, but in other highly conductive nanomaterials that ICPs compete with (e.g. silver nanowires, graphene and carbon nanotubes). These all suffer from aggregation issues and they remain difficult to stabilize to this day. Additional steps can be implemented to reduce these effects (e.g., chemical functionalization and dispersion agents) but those steps can also dramatically reduce the conductivity of the material. Unlike these other nanomaterials, though, ICPs have more flexibility to tune stability and conductivity.
There have been two classic approaches to breaking the conductivity-stability paradigm of ICPs: polymer chemistry and chemical doping. The Chemical doping approach has been widely successful. Conducting polymershave seen conductivity enhancements of over 103, by using certain dopants, allowing them to achieve performance levels similar to indium-doped tin oxide (ITO) used in touch screens. Unfortunately, this method of doping is limited to after the ICP has already been coated to form a thin film and often requires additional post-processing steps (e.g., heat, solvent exposure, etc.) that make it difficult to utilize for many commercial applications. ICP dispersion into a secondary matrix material (i.e. composites) would be impossible using a chemical doping approach. Both tunable backbone chemistry and chemical dopants are intrinsically limited approaches to improve the dispersability/processability of ICPs. This is one reason that this promising class of materials has struggled to be fully commercialized.
PolyDrop’s technology breaks the current ICP paradigms by applying a novel stabilization mechanism: self-assembly. When dispersed in a solvent, ICP chains can be driven to self-assemble into nanostructures by controlling its compatibility with the solvent. For many conducting polymers, self-assembly can also lead to dramatic increases in conductivity due to a decrease on the percolation concentration. PolyDrop’s breakthrough technology leverages decades of ICP research in a novel way. A new, economical synthesis process has been designed to create ICP dispersions directly in organic and aqueous solvents, where other products such as poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)…
LVP 131 is the first product that combines high conductivity and dispersability in organic (i.e. toluene) and water-based solvents. LVP 131 can be added to epoxies, and polyurethane-based coating at as low as 3wt% and provide ESD protection.