Anisotropic Elastic Modulus of Oriented Regioregular Poly(3-hexylthiophene) Films

Specific morphological features of polymer semiconductors are often promoted in devices to optimize optoelectronic behavior. Less studied is the role of morphology on the mechanical properties of the film, such as elastic modulus, which is an important property for the development of flexible and stretchable devices. To gain insight into the morphological origin of elasticity in polymer semiconductors and its relationship to charge transport, we study the anisotropic in-plane elastic modulus of strain-aligned regioregular poly(3-hexylthiophene) (P3HT) films and compare the results to previously measured field effect charge mobility. The film morphology is varied through the amount of applied strain and post strain thermal annealing. Morphological characterization includes UV–vis optical spectroscopy and X-ray diffraction. The elastic modulus is measured using a buckling-based measurement technique. The elastic modulus of the film is found to decrease as the film is plastically strained. Thermally annealin...

[1]  R. Dauskardt,et al.  Molecular-Scale Understanding of Cohesion and Fracture in P3HT:Fullerene Blends. , 2015, ACS applied materials & interfaces.

[2]  B. Zhao,et al.  The effects of structural disorders and microstructural mechanisms on semi-crystalline P3HT behavior , 2015 .

[3]  Liyong Niu,et al.  Full‐Solution Processed Flexible Organic Solar Cells Using Low‐Cost Printable Copper Electrodes , 2014, Advanced materials.

[4]  R. J. Kline,et al.  Morphological Origin of Charge Transport Anisotropy in Aligned Polythiophene Thin Films , 2014 .

[5]  Hung Phan,et al.  High‐Mobility Field‐Effect Transistors Fabricated with Macroscopic Aligned Semiconducting Polymers , 2014, Advanced materials.

[6]  Michael W. Kudenov,et al.  Organic photovoltaic cells with controlled polarization sensitivity , 2014 .

[7]  Darren J. Lipomi,et al.  Best of Both Worlds: Conjugated Polymers Exhibiting Good Photovoltaic Behavior and High Tensile Elasticity , 2014 .

[8]  Christopher Bruner,et al.  Role of Molecular Weight on the Mechanical Device Properties of Organic Polymer Solar Cells , 2014 .

[9]  Kevin A. Cavicchi,et al.  Anisotropic Mechanical Properties of Aligned Polystyrene-block-polydimethylsiloxane Thin Films , 2013 .

[10]  Daniel A. Fischer,et al.  Charge Transport in Highly Face-On Poly(3-hexylthiophene) Films , 2013 .

[11]  M. Brinkmann,et al.  Large Scale Alignment and Charge Transport Anisotropy of pBTTT Films Oriented by High Temperature Rubbing , 2013 .

[12]  Bethany I Lemanski,et al.  Correlating Stiffness, Ductility, and Morphology of Polymer:Fullerene Films for Solar Cell Applications , 2013 .

[13]  M. Toney,et al.  Role of confinement and aggregation in charge transport in semicrystalline polythiophene thin films , 2012 .

[14]  A. Crosby,et al.  The Intrinsic Mechanical Properties of Rubrene Single Crystals , 2012, Advanced materials.

[15]  R. Joseph Kline,et al.  Nanoscale structure measurements for polymer-fullerene photovoltaics , 2012 .

[16]  M. Kaltenbrunner,et al.  Ultrathin and lightweight organic solar cells with high flexibility , 2012, Nature Communications.

[17]  K. Leo Organic light-emitting diodes: Efficient and flexible solution , 2011 .

[18]  Lee J. Richter,et al.  Anisotropic Structure and Charge Transport in Highly Strain‐Aligned Regioregular Poly(3‐hexylthiophene) , 2011 .

[19]  Yang Yang,et al.  Polarizing Organic Photovoltaics , 2011, Advanced materials.

[20]  Huanyu Cheng,et al.  Shear-enhanced adhesiveless transfer printing for use in deterministic materials assembly , 2011 .

[21]  H. Sirringhaus,et al.  Anisotropy of Charge Transport in a Uniaxially Aligned and Chain‐Extended, High‐Mobility, Conjugated Polymer Semiconductor , 2011 .

[22]  T. Someya,et al.  Flexible organic transistors and circuits with extreme bending stability. , 2010, Nature materials.

[23]  R. J. Kline,et al.  Correlations between mechanical and electrical properties of polythiophenes. , 2010, ACS nano.

[24]  A. Salleo,et al.  Microstructural Origin of High Mobility in High‐Performance Poly(thieno‐thiophene) Thin‐Film Transistors , 2010, Advanced materials.

[25]  M. Toney,et al.  Charge‐Transport Anisotropy Due to Grain Boundaries in Directionally Crystallized Thin Films of Regioregular Poly(3‐hexylthiophene) , 2009 .

[26]  Jenny Clark,et al.  Determining exciton bandwidth and film microstructure in polythiophene films using linear absorption spectroscopy , 2009, 0903.1670.

[27]  R. Friend,et al.  Excitonic versus electronic couplings in molecular assemblies: The importance of non-nearest neighbor interactions. , 2009, The Journal of chemical physics.

[28]  R. Friend,et al.  Role of intermolecular coupling in the photophysics of disordered organic semiconductors: aggregate emission in regioregular polythiophene. , 2007, Physical review letters.

[29]  Brandon M. Vogel,et al.  Measuring molecular order in poly(3-alkylthiophene) thin films with polarizing spectroscopies. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[30]  F. Spano Absorption in regio-regular poly(3-hexyl)thiophene thin films: Fermi resonances, interband coupling and disorder , 2006 .

[31]  Donal D. C. Bradley,et al.  A strong regioregularity effect in self-organizing conjugated polymer films and high-efficiency polythiophene:fullerene solar cells , 2006 .

[32]  F. Spano,et al.  Modeling disorder in polymer aggregates: the optical spectroscopy of regioregular poly(3-hexylthiophene) thin films. , 2005, The Journal of chemical physics.

[33]  R. Street,et al.  Transport in polycrystalline polymer thin-film transistors , 2005 .

[34]  Willi Volksen,et al.  A buckling-based metrology for measuring the elastic moduli of polymeric thin films , 2004, Nature materials.

[35]  M. Grell,et al.  Highly polarized blue electroluminescence from homogeneously aligned films of poly(9,9-dioctylfluorene) , 2000 .

[36]  E. W. Meijer,et al.  Two-dimensional charge transport in self-organized, high-mobility conjugated polymers , 1999, Nature.

[37]  H. Sirringhaus,et al.  Integrated optoelectronic devices based on conjugated polymers , 1998, Science.

[38]  A. Basu,et al.  Mechanical properties of oriented fibres of semicrystalline polymers based upon orientation function from optical properties , 1986 .

[39]  I. Ward,et al.  Anisotropy of ultra-high modulus polymers drawn through a die , 1984 .

[40]  B. F. Blumentritt Anisotropy and dimensional stability of biaxially oriented poly(ethylene terephthalate) films , 1979 .

[41]  I. Ward,et al.  Ultra-high-modulus linear polyethylene through controlled molecular weight and drawing , 1975 .

[42]  A. Coran,et al.  Unidirectional fiber–polymer composites: Swelling and modulus anisotropy , 1971 .

[43]  P. R. Pinnock,et al.  Anisotropy in oriented fibres from synthetic polymers , 1969 .

[44]  I. Ward Optical and Mechanical Anisotropy in Crystalline Polymers , 1962 .

[45]  D. W. Saunders,et al.  The Anisotropy of Young's Modulus in Drawn Polyethylene , 1961 .

[46]  Eric J. Sawyer,et al.  Mechanical degradation and stability of organic solar cells: molecular and microstructural determinants , 2015 .

[47]  H. Sirringhaus 25th Anniversary Article: Organic Field-Effect Transistors: The Path Beyond Amorphous Silicon , 2014, Advanced materials.

[48]  Jeff Moulton,et al.  Electrical and mechanical properties of oriented poly(3-alkylthiophenes): 2. Effect of side-chain length , 1992 .

[49]  A. Heeger,et al.  Mechanical and electrical properties of polyacetylene films oriented by tensile drawing , 1991 .