Rubber Surface Change and Static Charging under Periodic Stress

Rubber materials play an important role in robotics, due to their sensing and actuating abilities, that are exploited in soft smart materials endowed with shape-adaptive and electroadhesive properties. The application of an electric field produces non-linear deformation that has been extensively modelled, but is not understood at the molecular level. The symmetric effect (the production of an electric field due to rubber deformation) was recently discovered and explained as follows: rubber surface chemical composition and adsorptive properties change during rubber deformation, allowing the surface to exchange charge with the atmosphere. The present work describes the complex surface morphology and microchemistry of tubing made from vulcanized natural rubber, showing that it is rough and made from two domain types: stiffer elevations containing Br or Al (depending on the sample used) and O, that rise above an elastic base that is exempt of elements other than C and H. The surface area fraction occupied by the elastic base is higher in the strained rubber than when it is relaxed. Electrostatic potential on rubber surfaces was measured as a function of the stretching frequency, using Kelvin electrodes and showing frequency-dependent potential variation. This is explained considering charge exchange between the atmosphere and rubber surface, mediated by water vapor adsorbed in the stretched rubber and trapped when it relaxes.

[1]  Jian Zhu,et al.  Control of a muscle-like soft actuator via a bioinspired approach , 2018, Bioinspiration & biomimetics.

[2]  Jonathan Rossiter,et al.  A soft and shape-adaptive electroadhesive composite gripper with proprioceptive and exteroceptive capabilities , 2018, Materials & Design.

[3]  Michael D. Grissom,et al.  Resonant frequency tuning of electroactive polymer membranes via an applied bias voltage , 2018, Smart Materials and Structures.

[4]  E. Bortot.  Nonlinear dynamic response of soft thick-walled electro-active tubes , 2018, Smart Materials and Structures.

[5]  P. Sharma,et al.  Emergent magnetoelectricity in soft materials, instability, and wireless energy harvesting. , 2018, Soft matter.

[6]  O. A. Lambri,et al.  Electric memory effects in styrene-butadiene rubber, containing electric inclusions of highly aromatic oil , 2018, Journal of Advanced Dielectrics.

[7]  Yibin Fu,et al.  Localized necking of a dielectric membrane , 2018 .

[8]  Andri Andriyana,et al.  Recent advances on fatigue of rubber after the literature survey by Mars and Fatemi in 2002 and 2004 , 2018 .

[9]  T. Burgo,et al.  Electricity on Rubber Surfaces: A New Energy Conversion Effect , 2017, ACS omega.

[10]  R. Ogden,et al.  Nonlinear electroelasticity: material properties, continuum theory and applications , 2017, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[11]  Xiaoling Jin,et al.  Random response of dielectric elastomer balloon to electrical or mechanical perturbation , 2017 .

[12]  R. McMeeking,et al.  A constitutive law for dielectric elastomers subject to high levels of stretch during combined electrostatic and mechanical loading: Elastomer stiffening and deformation dependent dielectric permittivity , 2016 .

[13]  Guang Zhu,et al.  Triboelectric nanogenerators as a new energy technology: From fundamentals, devices, to applications , 2015 .

[14]  Tongqing Lu,et al.  Experimental investigation of the electromechanical phase transition in a dielectric elastomer tube , 2015 .

[15]  Liang Chen,et al.  Toughening mystery of natural rubber deciphered by double network incorporating hierarchical structures , 2014, Scientific Reports.

[16]  Giovanni Berselli,et al.  Design of a Dielectric Elastomer Cylindrical Actuator With Quasi-Constant Available Thrust: Modeling Procedure and Experimental Validation , 2014 .

[17]  J. Martín-Martínez,et al.  Surface treatment with UV-ozone to improve adhesion of vulcanized rubber formulated with an excess of processing oil , 2014 .

[18]  E. Toussaint,et al.  Thermomechanical analysis of the crack tip zone in stretched crystallizable natural rubber by using infrared thermography and digital image correlation , 2014 .

[19]  F. Galembeck,et al.  Triboelectricity in insulating polymers: evidence for a mechanochemical mechanism. , 2014, Faraday discussions.

[20]  Todd A. Gisby,et al.  Self sensing feedback for dielectric elastomer actuators , 2013 .

[21]  L. Vanel,et al.  Fatigue crack growth dynamics in filled natural rubber , 2012 .

[22]  Fernando Galembeck,et al.  Triboelectricity: macroscopic charge patterns formed by self-arraying ions on polymer surfaces. , 2012, Langmuir : the ACS journal of surfaces and colloids.

[23]  M. Sow,et al.  Strain-induced reversal of charge transfer in contact electrification. , 2012, Angewandte Chemie.

[24]  J. Martín-Martínez,et al.  Migration of Paraffin Wax to Sulfur Vulcanized Styrene–Butadiene Rubber (SBR) Surface: Effect of Temperature , 2012 .

[25]  Adnan Harb,et al.  Energy harvesting: State-of-the-art , 2011 .

[26]  C. A. Rezende,et al.  Electric potential decay on polyethylene: Role of atmospheric water on electric charge build-up and dissipation , 2011 .

[27]  Evelyne Toussaint,et al.  The Mechanism of Fatigue Crack Growth in Rubbers under Severe Loading: the Effect of Stress-Induced Crystallization , 2010 .

[28]  Timothy C. Green,et al.  Energy Harvesting From Human and Machine Motion for Wireless Electronic Devices , 2008, Proceedings of the IEEE.

[29]  L. B. Schein,et al.  Recent Progress and Continuing Puzzles in Electrostatics , 2007, Science.

[30]  L. Ter-minassian-saraga,et al.  Chemical structures of surface‐oxidized and grafted polyethylene: Adsorption and wetting studies , 2007 .

[31]  Ali Fatemi,et al.  Factors that affect the fatigue life of rubber: A literature survey , 2004 .

[32]  E. Verron,et al.  Mechanism of Fatigue Crack Growth in Carbon Black Filled Natural Rubber , 2004 .

[33]  Lay-Theng Lee,et al.  Skim and cream natural rubber particles: colloidal properties, coalescence and film formation. , 2003, Journal of colloid and interface science.

[34]  P. Albouy,et al.  Stress-Induced Crystallization around a Crack Tip in Natural Rubber , 2002 .

[35]  Ali Fatemi,et al.  A literature survey on fatigue analysis approaches for rubber , 2002 .

[36]  J. Zhao,et al.  A Review of Some of the Factors Affecting Fracture and Fatigue in SBR and BR Vulcanizates , 2001 .

[37]  A. Bailey.  The charging of insulator surfaces , 2001 .

[38]  G.S.P. Castle,et al.  Contact charging between insulators , 1997 .

[39]  G. J. Lake.  Fatigue and Fracture of Elastomers , 1995 .

[40]  S. Nunes,et al.  Tracking degradation and pyrolysis of EPDM insulators , 1989 .

[41]  V. Gul',et al.  The Effect of Electric Charges Formed during Repeated Deformations on the Fatigue Resistance of Vulcanizates , 1960 .

[42]  Marc Doumit,et al.  Biaxial experimental and analytical characterization of a dielectric elastomer , 2017 .

[43]  L. Coltro,et al.  A staining procedure for the detection of oxidized sites in polyolefins , 1990 .

[44]  A. A. Griffith.  The Phenomena of Rupture and Flow in Solids , 1921 .