Supramolecular ionics: electric charge partition within polymers and other non-conducting solids

Electrostatic phenomena in insulators have been known for the past four centuries, but many related questions are still unanswered, for instance: which are the charge-bearing species in an electrified organic polymer, how are the charges spatially distributed and which is the contribution of the electrically charged domains to the overall polymer properties? New scanning probe microscopies were recently introduced, and these are suitable for the mapping of electric potentials across a solid sample thus providing some answers for the previous questions. In this work, we report results obtained with two of these techniques: scanning electric potential (SEPM) and electric force microscopy (EFM). These results were associated to images acquired by using analytical electron microscopy (energy-loss spectroscopy imaging in the transmission electron microscope, ESI-TEM) for colloid polymer samples. Together, they show domains with excess electric charges (and potentials) extending up to hundreds of nanometers and formed by large clusters of cations or anions, reaching supramolecular dimensions. Domains with excess electric charge were also observed in thermoplastics as well as in silica, polyphosphate and titanium oxide particles. In the case of thermoplastics, the origin of the charges is tentatively assigned to their tribochemistry, oxidation followed by segregation or the Mawell-Wagner-Sillars and Costa Ribeiro effects.

[1]  Fernando Galembeck,et al.  Core-and-shell nature of Stöber silica particles , 2001 .

[2]  F. Galembeck,et al.  Latex macrocrystal self-assembly dependence on particle chemical heterogeneity , 2001 .

[3]  J. Kolar̆ík,et al.  Dielectric behaviour of polycarbonate/poly(styrene-co-acrylonitrile) and polycarbonate/poly(methyl methacrylate) two-phase blends , 2001 .

[4]  T. Jones.  Liquid dielectrophoresis on the microscale , 2001 .

[5]  A. Galembeck,et al.  Scanning electric potential microscopy imaging of polymers: electrical charge distribution in dielectrics , 2001 .

[6]  A. Bailey,et al.  Characterisation of electrostatic discharges from insulating surfaces , 2001 .

[7]  F. Galembeck,et al.  Scanning Electric Potential Microscopy Imaging of Polymer Latex Films: Detection of Supramolecular Domains with Nonuniform Electrical Characteristics , 2001 .

[8]  F. Galembeck,et al.  Nanocrystalline Domain Identification in Gold Films, by Backscattered Electron Imaging and Energy-Filtered Transmission Electron Microscopy. , 2001, Journal of Colloid and Interface Science.

[9]  J. Amalvy,et al.  Elemental mapping by ESI–TEM, during styrene emulsion polymerization , 2001 .

[10]  A. Galembeck,et al.  Macrocrystal Swelling: AFM in Situ Observation of Particle and Film Deformation and Motion. , 2001, Journal of colloid and interface science.

[11]  T. Jones,et al.  Dielectrophoretic liquid actuation and nanodroplet formation , 2001 .

[12]  Galembeck,et al.  Latex Fractionation by Sedimentation and Colloidal Crystallization: The Case of Poly(styrene-co-acrylamide). , 2000, Journal of colloid and interface science.

[13]  Wu,et al.  Ion penetration of the water-Oil interface , 1999, Science.

[14]  F. Galembeck,et al.  PS-HEMA latex fractionation by sedimentation and colloidal crystallization , 1999 .

[15]  Galembeck,et al.  Aluminum Polyphosphate Nanoparticles: Preparation, Particle Size Determination, and Microchemistry. , 1999, Journal of colloid and interface science.

[16]  F. Galembeck,et al.  Latex Particle Self-Assembly and Particle Microchemical Symmetry: PS/HEMA Latex Particles Are Intrinsic Dipoles , 1999 .

[17]  J. C. Cañadas,et al.  Windowing polarization: considerations for the study of the space charge relaxation in poly(methyl methacrylate) by thermally stimulated depolarization currents , 1999 .

[18]  J. A. Malecki,et al.  Linear decay of charge in electrets , 1999 .

[19]  F. Galembeck,et al.  Elemental Distribution within Single Latex Particles: Determination by Electron Spectroscopy Imaging , 1998 .

[20]  Jean-Pierre Crine,et al.  A molecular model to evaluate the impact of aging on space charges in polymer dielectrics , 1997 .

[21]  R. Penner,et al.  Electrostatic force microscopy of silver nanocrystals with nanometer-scale resolution , 1997 .

[22]  I. A. Karpovich,et al.  Ion beam effects in polymer films: Structure evolution of the implanted layer , 1997 .

[23]  A. S. Hou,et al.  Tapping mode atomic force microscopy using electrostatic force modulation , 1996 .

[24]  H. Schmidt,et al.  Piezoelectric polymer electrets , 1996 .

[25]  Reimund Gerhard-Multhaupt,et al.  Nonlinear optical polymer electrets current practice , 1996 .

[26]  J.-L. Parpal,et al.  Electrical aging of extruded dielectric cables: review of existing theories and data , 1996 .

[27]  C. Laurent,et al.  Electroluminescence from polyolefins subjected to a homogeneous ac field , 1995 .

[28]  K. Suh,et al.  Electrical conduction in polyethylene with semiconductive electrodes , 1994 .

[29]  H. K. Wickramasinghe,et al.  Kelvin probe force microscopy , 1991 .

[30]  B. Terris,et al.  Imaging of ferroelectric domain walls by force microscopy , 1990 .

[31]  K. Holdik,et al.  Electric Field-Induced Gas Emission from PVDF Films , 1987, IEEE Transactions on Electrical Insulation.

[32]  T. Hibma,et al.  Direct measurement of space‐charge injection from a needle electrode into dielectrics , 1986 .

[33]  W. Possart,et al.  Measurement of Electrical Potential Distribution in a Polymer near the Contact to a Metal by Means of Scanning Electron Microscopy , 1984, July 16.

[34]  J. Crine.  Influence of Electric Field and Low Pressure on the Activation Energy for Conduction in Polyethylene , 1982, August 16.

[35]  J. D. Ranade,et al.  Thermally stimulated discharge currents in polystyrene films , 1980 .

[36]  C. Lacabanne,et al.  Thermally stimulated current (TSC) study of the Tg and Tll transitions in anionic polystyrenes , 1980 .

[37]  P. Eyerer.  Electric charge separation and charge storage during phase changes in the absence of external electric fields: thermodielectric effect (costa Ribeiro effect) and workman-Reynolds effect , 1972 .

[38]  V. S. Kuksenko,et al.  Mechanism of submicrocrack generation in stressed polymers , 1972 .

[39]  B. Derjaguin,et al.  Electronic Theory of Adhesion , 1967 .

[40]  S. Skinner.  Diffusion, Static Charges, and the Conduction of Electricity in Nonmetallic Solids by a Single Charge Carrier. II. Solution of the Rectifier Equations for Insulating Layers , 1955 .

[41]  R. L. Savage,et al.  Electrical Phenomena in Adhesion. I. Electron Atmospheres in Dielectrics , 1953 .

[42]  F. Galembeck,et al.  Size Effects on the Microchemistry and Plasticity of Stöber Silica Particles: A Study Using EFTEM, FESEM, and AFM-SEPM Microscopies , 2001 .

[43]  W. Bolton.  Electrical and magnetic properties of materials , 1992 .

[44]  J. E. Stern,et al.  Localized charge force microscopy , 1990 .

[45]  J. P. Schwar,et al.  Factors Affecting Separations of Suspensions in Nonuniform Electric Fields , 1959 .