Dynamic Visualization of Stress/Strain Distribution and Fatigue Crack Propagation by an Organic Mechanoresponsive AIE Luminogen

Stress exists ubiquitously and is critically important for the manufacturing industry. Due to the ultrasensitive mechanoresponse of the emission of 1,1,2,2,-tetrakis(4-nitrophenyl)ethane (TPE-4N), a luminogen with aggregation-induced emission characteristics, the visualization of stress/strain distributions on metal specimens with a pure organic fluorescent material is achieved. Such a fluorescence mapping method enjoys the merits of simple setup, real-time, full-field, on-site, and direct visualization. Surface analysis shows that TPE-4N can form a nonfluorescent, crystalline uniform film on the metal surface, which cracks into fluorescent amorphous fragments upon mechanical force. Therefore, the invisible information of the stress/strain distribution of the metal specimens are transformed to visible fluorescent signals, which generally matches well but provides more details than software simulation. Remarkably, fatigue crack propagation in stainless steel and aluminum alloy can be observed and predicted clearly, further demonstrating the ultrasensitivity and practicability of TPE-4N.

[1]  K J Miller,et al.  Metal Fatigue—Past, Current and Future , 1991 .

[2]  Jeffrey S. Moore,et al.  Shear activation of mechanophore-crosslinked polymers , 2011 .

[3]  Costantino Creton,et al.  Toughening Elastomers with Sacrificial Bonds and Watching Them Break , 2014, Science.

[4]  Scott R White,et al.  Mechanophore-linked addition polymers. , 2007, Journal of the American Chemical Society.

[5]  K. Wada,et al.  Modulation of luminescence chromic behaviors and environment-responsive intensity changes by substituents in bis-o-carborane-substituted conjugated molecules , 2018 .

[6]  Mary M. Caruso,et al.  Mechanically-induced chemical changes in polymeric materials. , 2009, Chemical reviews.

[7]  Gregor Schwartz,et al.  White organic light-emitting diodes with fluorescent tube efficiency , 2009, Nature.

[8]  Anand Asundi,et al.  Two-dimensional digital image correlation for in-plane displacement and strain measurement: a review , 2009 .

[9]  B. Tang,et al.  Fluorescent chemosensor for detection and quantitation of carbon dioxide gas. , 2010, Journal of the American Chemical Society.

[10]  Franccois Hild,et al.  Digital Image Correlation: from Displacement Measurement to Identification of Elastic Properties – a Review , 2006 .

[12]  C. Weder,et al.  Oligo(p-phenylene vinylene) Excimers as Molecular Probes: Deformation-Induced Color Changes in Photoluminescent Polymer Blends , 2002 .

[13]  Dongge Ma,et al.  Approaches to high performance white organic light-emitting diodes for general lighting , 2017 .

[14]  Ben Zhong Tang,et al.  Aggregation‐Induced Emission: The Whole Is More Brilliant than the Parts , 2014, Advanced materials.

[15]  Fuqian Yang,et al.  Optical response of a quantum dot–epoxy resin composite: effect of tensile strain , 2016 .

[16]  Jia-rui Xu,et al.  Recent advances in organic mechanofluorochromic materials. , 2012, Chemical Society reviews.

[17]  Zhengke Wang,et al.  Gelation process visualized by aggregation-induced emission fluorogens , 2016, Nature Communications.

[18]  E. W. Meijer,et al.  Mechanically induced chemiluminescence from polymers incorporating a 1,2-dioxetane unit in the main chain. , 2012, Nature chemistry.

[19]  Ben Zhong Tang,et al.  Aggregation-induced emission. , 2011, Chemical Society reviews.

[20]  Ben Zhong Tang,et al.  Fluorescence microscopy as an alternative to electron microscopy for microscale dispersion evaluation of organic–inorganic composites , 2016, Nature Communications.

[21]  R. Sijbesma,et al.  Dioxetanes as Mechanoluminescent Probes in Thermoplastic Elastomers , 2014 .

[22]  Yongqiang Dong,et al.  Mechanochromic Luminescence of Aggregation-Induced Emission Luminogens. , 2015, The journal of physical chemistry letters.

[23]  Zhen Li,et al.  Molecular conformation and packing: their critical roles in the emission performance of mechanochromic fluorescence materials , 2017 .

[24]  C. Adachi,et al.  Efficient blue organic light-emitting diodes employing thermally activated delayed fluorescence , 2014, Nature Photonics.

[25]  Stephen Schrettl,et al.  Mechano- and Thermoresponsive Photoluminescent Supramolecular Polymer. , 2017, Journal of the American Chemical Society.

[26]  Nancy R. Sottos,et al.  A Robust Damage-Reporting Strategy for Polymeric Materials Enabled by Aggregation-Induced Emission , 2016, ACS central science.

[27]  M Ph Papaelias,et al.  A review on non-destructive evaluation of rails: State-of-the-art and future development , 2008 .

[28]  Mitchell T. Ong,et al.  Force-induced activation of covalent bonds in mechanoresponsive polymeric materials , 2009, Nature.

[29]  Yongqiang Dong,et al.  Highly sensitive switching of solid-state luminescence by controlling intersystem crossing , 2018, Nature Communications.

[30]  Xinwei Wang,et al.  Thermal probing in single microparticle and microfiber induced near-field laser focusing. , 2013, Optics express.

[31]  Kee-Sun Sohn,et al.  Dynamic visualization of crack propagation and bridging stress using the mechano-luminescence of SrAl2O4: (Eu,Dy,Nd) , 2003 .

[32]  Ryan T. K. Kwok,et al.  A Simple and Sensitive Method for an Important Physical Parameter: Reliable Measurement of Glass Transition Temperature by AIEgens , 2017 .

[33]  Ryan T. K. Kwok,et al.  Aggregation-Induced Emission: Together We Shine, United We Soar! , 2015, Chemical reviews.

[34]  H. Neuber Theory of Stress Concentration for Shear-Strained Prismatical Bodies With Arbitrary Nonlinear Stress-Strain Law , 1961 .

[35]  P. Thilagar,et al.  Stimuli and shape responsive ‘boron-containing’ luminescent organic materials , 2016 .

[36]  Lin Zhang,et al.  Dynamic visualization of stress distribution on metal by mechanoluminescence images , 2008, J. Vis..

[37]  Ian D. Williams,et al.  Synergy between Twisted Conformation and Effective Intermolecular Interactions: Strategy for Efficient Mechanochromic Luminogens with High Contrast , 2013, Advanced materials.