Polymer cold-drawing1,2,3,4 is a process in which tensile stress reduces the diameter of a drawn fibre (or thickness of a drawn film) and orients the polymeric chains. Cold-drawing has long been used in industrial applications5,6,7, including the production of flexible fibres with high tensile strength such as polyester and nylon8,9. However, cold-drawing of a composite structure has been less studied. Here we show that in a multimaterial fibre10,11 composed of a brittle core embedded in a ductile polymer cladding, cold-drawing results in a surprising phenomenon: controllable and sequential fragmentation of the core to produce uniformly sized rods along metres of fibre, rather than the expected random or chaotic fragmentation. These embedded structures arise from mechanical–geometric instabilities associated with ‘neck’ propagation2,3. Embedded, structured multimaterial threads with complex transverse geometry are thus fragmented into a periodic train of rods held stationary in the polymer cladding. These rods can then be easily extracted via selective dissolution of the cladding, or can self-heal by thermal restoration to re-form the brittle thread. Our method is also applicable to composites with flat rather than cylindrical geometries, in which case cold-drawing leads to the break-up of an embedded or coated brittle film into narrow parallel strips that are aligned normally to the drawing axis. A range of materials was explored to establish the universality of this effect, including silicon, germanium, gold, glasses, silk, polystyrene, biodegradable polymers and ice. We observe, and verify through nonlinear finite-element simulations, a linear relationship between the smallest transverse scale and the longitudinal break-up period. These results may lead to the development of dynamical and thermoreversible camouflaging via a nanoscale Venetian-blind effect, and the fabrication of large-area structured surfaces that facilitate high-sensitivity bio-detection.
This is a preview of subscription content, access via your institution
Open Access articles citing this article.
Advanced Fiber Materials Open Access 07 January 2020
Nature Communications Open Access 15 November 2019
Scientific Reports Open Access 14 October 2016
Subscribe to Journal
Get full journal access for 1 year
only $3.90 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Get time limited or full article access on ReadCube.
All prices are NET prices.
Carothers, W. H. & Hill, J. W. Studies of polymerization and ring formation. XV. Artificial fibers from synthetic linear condensation superpolymers. J. Am. Chem. Soc. 54, 1579–1587 (1932)
Vincent, P. I. The necking and cold-drawing of rigid plastics. Polymer 1, 7–19 (1960)
Coleman, B. D. On the cold drawing of polymers. Comput. Math. Appl. 11, 35–65 (1985)
Argon, A. S. The Physics of Deformation and Fracture of Polymers Ch. 10 (Cambridge Univ. Press, 2013)
Carothers, W. H. Synthetic fiber. US patent 2,130,948 (1938)
Marshall, I. & Thompson, A. B. Drawing synthetic fibres. Nature 171, 38–39 (1953)
Hermes, M. Enough for One Lifetime: Wallace Carothers, Inventor of Nylon (Chemical Heritage Foundation, 1996)
Ziabicki, A. Fundamentals of Fibre Formation: The Science of Fibre Spinning and Drawing (Wiley, 1976)
Carraher, C. E. Jr. Introduction to Polymer Chemistry 3rd edn (CRC Press, 2012) edition
Abouraddy, A. F. et al. Towards multimaterial multifunctional fibres that see, hear, sense and communicate. Nature Mater. 6, 336–347 (2007)
Tao, G., Stolyarov, A. M. & Abouraddy, A. F. Multimaterial fibers. Int. J. Appl. Glass Sci. 3, 349–368 (2012)
Loos, J., Schimanski, T., Hofman, J., Peijs, T. & Lemstra, P. J. Morphological investigations of polypropylene single-fibre reinforced polypropylene model composites. Polymer 42, 3827–3834 (2001)
Friedrich, K. et al. Microfibrillar reinforced composites from PET/PP blends: processing, morphology and mechanical properties. Compos. Sci. Technol. 65, 107–116 (2005)
Fakirov, S., Bhattacharyya, D., Lin, R. J. T., Fuchs, C. & Friedrich, K. Contribution of coalescence to microfibril formation in polymer blends during cold drawing. J. Macromol. Sci. B 46, 183–194 (2007)
Nairn, J. A. On the use of shear-lag methods for analysis of stress-transfer in unidirectional composites. Mech. Mater. 26, 63–80 (1997)
Asloun, Ei. M., Nardin, M. & Schultz, J. Stress transfer in single-fibre composites: effect of adhesion, elastic modulus of fibre and matrix, and polymer chain mobility. J. Mater. Sci. 24, 1835–1844 (1989)
Wang, X., Zhang, B., Du, S., Wu, Y. & Sun, X. Numerical simulation of the fiber fragmentation process in single-fiber composites. Mater. Des. 31, 2464–2470 (2010)
Ballato, J. et al. Silicon optical fiber. Opt. Express 16, 18675–18683 (2008)
Tao, G. et al. Infrared fibers. Adv. Opt. Photon. 7, 379–458 (2015)
Cox, H. L. The elasticity and strength of paper on other fibrous materials. Br. J. Appl. Phys. 3, 72–79 (1952)
Boyce, M. C., Montagut, E. L. & Argon, A. S. The effects of thermomechanical coupling on the cold drawing process of glassy polymers. Polym. Eng. Sci. 32, 1073–1085 (1992)
Lu, N., Suo, Z. & Vlassak, J. J. The effect of film thickness on the failure strain of polymer-supported metal films. Acta Mater. 58, 1679–1687 (2010)
Saleh, B. E. A. & Teich, M. C. Fundamentals of Photonics 2nd edn (Wiley, 2007)
Zartman, G. D. et al. How melt-stretching affects mechanical behavior of polymer glasses. Macromolecules 45, 6719–6732 (2012)
Kaufman, J. J. et al. Thermal drawing of high-density macroscopic arrays of well-ordered sub-5-nm-diameter nanowires. Nano Lett. 11, 4768–4773 (2011)
Stören, S. & Rice, J. R. Localized necking in thin sheets. J. Mech. Phys. Solids 23, 421–441 (1975)
Bai, Y. & Wierzbicki, T. Forming severity concept for predicting sheet necking under complex loading histories. Int. J. Mech. Sci. 50, 1012–1022 (2008)
Fang, T. H., Li, W. L., Tao, N. R. & Lu, K. Revealing extraordinary intrinsic tensile plasticity in gradient nano-grained copper. Science 331, 1587–1590 (2011)
Schulson, E. M. The structure and mechanical behavior of ice. J. Miner. Met. Mater. Soc. 51, 21–27 (1999)
Li, T. (ed.). Optical Fiber Communications: Fiber Fabrication Vol. 1 (Academic Press, 1985)
ABAQUS User’s Manual, version 6.11 (Simulia, Inc., 2011)
Mital, S. K., Murthy, P. L. N. & Chamis, C. C. Interfacial microfracture in high temperature metal matrix composites. J. Compos. Mater. 27, 1678–1694 (1993)
Hillerborg, A., Modéer, M. & Petersson, P.-E. Analysis of crack formation and crack growth in concrete by means of fracture mechanics and finite elements. Cement Concr. Res. 6, 773–781 (1976)
Hutchinson, J. W. & Neale, K. W. Neck propagation. J. Mech. Phys. Solids 31, 405–426 (1983)
Neale, K. W. & Tuḡcu, P. Analysis of necking and neck propagation in polymeric materials. J. Mech. Phys. Solids 33, 323–337 (1985)
Anand, L. & Gurtin, M. E. A theory of amorphous solids undergoing large deformations, with application to polymeric glasses. Int. J. Solids Struct. 40, 1465–1487 (2003)
Ung, B. & Skorobogatiy, M. Chalcogenide microporous fibers for linear and nonlinear applications in the mid-infrared. Opt. Express 18, 8647–8659 (2010)
Figueroa, J. C., Carney, T. E., Schadler, L. S. & Laird, C. Micromechanics of single filament composites. Compos. Sci. Technol. 42, 77–101 (1991)
Galiotis, G. & Paipetis, A. Definition and measurement of the shear-lag parameter, β, as an index of the stress transfer efficiency in polymer composites. J. Mater. Sci. 33, 1137–1143 (1998)
Kim, B. W. & Nairn, J. A. Observations of fiber fracture and interfacial debonding phenomena using the fragmentation test in single fiber composites. J. Compos. Mater. 36, 1825–1858 (2002)
Thostenson, E. T., Li, W. Z., Wang, D. Z., Ren, Z. F. & Chou, T. W. Carbon nanotube/carbon fiber hybrid multiscale composites. J. Appl. Phys. 91, 6034–6037 (2002)
Kurkjian, C. R. Mechanical properties of phosphate glasses. J. Non-Cryst. Solids 263–264, 207–212 (2000)
Chang, K. H., Lee, T. H. & Hwa, L. G. Structure and elastic properties of iron phosphate glasses. Chin. J. Physiol. 41, 414–421 (2003)
Rouxel, T. Elastic properties and short- to medium-range order in glasses. J. Am. Ceram. Soc. 90, 3019–3039 (2007)
Pérez-Rigueiro, J., Viney, C., Llorca, J. & Elices, M. Mechanical properties of single-brin silkworm silk. J. Appl. Polym. Sci. 75, 1270–1277 (2000)
Cheung, H.-Y., Lau, K.-T., Ho, M.-P. & Mosallam, A. Study on the mechanical properties of different silkworm silk fibers. J. Compos. Mater. 43, 2521–2531 (2009)
Zhang, K., Si, F. W., Duan, H. L. & Wang, J. Microstructures and mechanical properties of silks of silkworm and honeybee. Acta Biomater. 6, 2165–2171 (2010)
Hartouni, E. & Mecholsky, J. J. Mechanical properties of chalcogenide glasses. Proc. SPIE 0683, 92–97 (1986)
Littler, I. C. M., Fu, L. B., Mägi, E. C., Pudo, D. & Eggleton, B. J. Widely tunable, acousto-optic resonances in chalcogenide As2Se3 fiber. Opt. Express 14, 8088–8095 (2006)
Tanaka, K. & Shimakawa, K. Amorphous Chalcogenide Semiconductors and Related Materials (Springer, 2011)
El-Mallawany, R. A. H. Tellurite Glasses Handbook: Physical Properties and Data (CRC Press, 2011)
Hu, Z. et al. Measurement of Young’s modulus and Poisson’s ratio of human hair using optical techniques. Proc. SPIE 7522, 75222Q (2010)
Kaplan, P. D. et al. Grey hair: clinical investigation into changes in hair fibres with loss of pigmentation in a photoprotected population. Int. J. Cosmet. Sci. 33, 171–182 (2011)
Nie, H.-Y., Motomatsu, M., Mizutani, W. & Tokumoto, H. Local modification of elastic properties of polystyrene–polyethyleneoxide blend surfaces. J. Vac. Sci. Technol. B 13, 1163–1166 (1995)
Bellan, L. M., Kameoka, J. & Craighead, H. G. Measurement of the Young's moduli of individual polyethylene oxide and glass nanofibers. Nanotechnology 16, 1095–1099 (2005)
Weeks, W. F. & Assur, A. The Mechanical Properties of Sea Ice (US Army Material Command, Cold Regions Research and Engineering Laboratory, 1967)
We thank E.-H. Banaei, L. N. Pye, F. Tan, A. Schülzgen, C. Jollivet, C. Cariker, A. Schulte, M. Lodge, M. Ishigami, E. Duenas, C. Burchett, M. Finke, Y. Xu, S. Dai, H. Ren and X. Wang for technical assistance. We also thank M. Rein, F. Sorin, M. Kolle, A. Dogariu, D. N. Christodoulides and B. E. A. Saleh for discussions. The authors acknowledge the University of Central Florida Stokes Advanced Research Computing Center for providing computational resources and support that have contributed to results reported here. We also thank Simulia, Inc. for providing the license of the ABAQUS software package. This work was supported by the US Air Force Office of Scientific Research (AFOSR) under contract FA-9550-12-1-0148 and AFOSR MURI contract FA9550-14-1-0037, and the US National Science Foundation (CMMI-1300773). This work was supported in part by the MIT MRSEC through the MRSEC Program of the National Science Foundation under award number DMR-1419807.
The authors declare no competing financial interests.
Extended data figures and tables
Extended Data Figure 1 Schematic contrasting controlled (sequential) and uncontrolled (random) thread fragmentation.
a, The designed fragmentation process that takes place during cold-drawing of a fibre consisting of a brittle core embedded in a ductile cladding. The overall length of the sample increases considerably when fully drawn. b, The random fragmentation that takes place during stress transfer in a composite sample consisting of a fibre embedded in a matrix. Thick purple arrows indicate externally applied stress.
Extended Data Figure 2 Stress–strain models of the materials used in the finite-element computational model.
a, Axisymmetric structure used in the computational model. P, polymer (PES); I, interfacial layer; C, core. The same polymer and interfacial layer are used in the cylindrical and flat fibre simulations. Various core materials are used. b, Stress–strain model for the PES cladding (‘P’ in a). c, Stress–strain model (including both elastic range and post-failure softening) for the PES interfacial layer (‘I’ in a). d, Stress–strain model for an As2Se3 core material (‘C’ in a). e, Stress–strain model for a silicon (Si) core; see Supplementary Figs 14 and 15.
The results of nonlinear finite-element simulations showing contour plots of the evolving von Mises stress distribution with increasing stretch, using the same (isotropic) materials (PES and As2Se3) as in the cylindrical case (Fig. 2e and Extended Data Fig. 2). The five steps (i)–(v) correspond to increasing stretch values. Top panels depict the full fibre; bottoms panels show the regions corresponding to that highlighted by the rectangle in (i). P, polymer (PES); G, glass (As2Se3).
Each row corresponds to a different thickness of gold (20 nm, 30 nm, 40 nm and 70 nm) sputtered onto a 75-μm-thick PES film. The columns show SEM micrographs of the gold films after cold-drawing at two different scales to highlight the dependence of the average fragment size on the thickness of the gold layer. P, PES film; Au, sputtered gold.
Extended Data Figure 5 Spectral diffraction measurements from a gold film fragmented by cold-drawing.
a, Optical set-up used to measure the spectrum of light diffracted at an angle θ from a thin gold film of thickness 70 nm on a 75-μm-thick PES film after fragmentation via cold-drawing (Extended Data Fig. 4, first row). OSA, optical spectrum analyser; FC, fibre coupler; θ is the angle with respect to normal incidence on the film. b, Measured diffracted spectra on a vertical logarithmic scale. The spectra are normalized with respect to the input optical spectrum. Each spectrum is then normalized to its maximum value.
a, b, Photographs depicting the cold-drawing procedure. a, A line is drawn on a 75-μm-thick PES film (5 mm × 10 cm) using a dry-erase marker pen. b, Using two pliers, the two ends of the strip are pulled symmetrically by hand until cold-drawing is complete. c, After cold-drawing, the optical appearance of the strip changes and coloured diffracted bands are apparent to the naked eye (the marker pen is used to write across the whole film surface). d, SEM micrograph of the drawn line reveals that a crust is formed at the PES surface that fragments into strips that are orthogonal to the cold-drawing axis (similarly to in Figs 3 and 4f), which are behind the new optical properties of the strip seen in c. e, SEM micrograph of the edge of the drawn line, showing a tapering of the thickness of the ink crust, and concomitant drop in fragmentation period. I, ink-polymer crust; P, PES polymer film.
This file contains Supplementary Text, Supplementary Figures 1-17 and Supplementary References. (PDF 2158 kb)
Real time videos of the cold-drawing of a 20 μm diameter As2Se3 glass fibre contained in PES cladding of 1 mm outer diameter. 7 different experiments are shown in this video, where the dimensions of each fibre are the same, but the cold-drawing speed and fibre pre-stress are varied. (MP4 22163 kb)
Animation of cold-drawing-induced fragmentation process for cylindrical fibres; details of the simulations can be found in Methods. (MP4 24403 kb)
Real time videos of the cold-drawing of a 300 nm thick layer of As2Se3 glass embedded in a 1mm wide, 350 μm thick PES cladding. 6 different experiments are shown in this video, where the dimensions of each fibre are the same, but the cold-drawing speed and fibre pre-stress are varied. This video was replaced on 10 June 2016 as the original video was corrupted. (MP4 9195 kb)
Animation of cold-drawing-induced fragmentation process for flat fibres; details of the simulations can be found in Methods. (MP4 27589 kb)
A 1-mm-wide flat PES fibre containing six cylindrical 20-mm-diameter As2Se3 cores is cold-drawn in real time, with a pre-stress of 30 g and at a speed of 20 mm/min. Two segments of the video show two different zooms of the fibre. (MP4 9080 kb)
About this article
Cite this article
Shabahang, S., Tao, G., Kaufman, J. et al. Controlled fragmentation of multimaterial fibres and films via polymer cold-drawing. Nature 534, 529–533 (2016). https://doi.org/10.1038/nature17980
Effect of the uniaxial orientation on the polymer/filler nanocomposites using phosphonate-modified single-walled carbon nanotube with hydro- or fluorocarbons
Polymer Bulletin (2021)
Advanced Fiber Materials (2020)
Nature Communications (2019)
Nature Protocols (2018)
Scientific Reports (2016)