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In this study, textured composite surface with protruding fibers is developed, which exhibits extremely high coefficient of friction on ice. A novel composite material with improved wear resistibility is aimed to determine with the target to maintain its slip‐resistance properties over extended use. Particularly, two thermoplastic elastomers are compared, namely, thermoplastic polyurethanes (TPU) and Styrene–Butadiene–Styrene (SBS), reinforced with five types of fibers with varying stiffnesses and ductility, including alumina, basalt, glass, carbon, and poly(p‐phenylene‐2,6‐benzobisoxazole)) (PBO). The surface science of the composite is analyzed by using Fourier tranorm infrared spectroscopy to assess the intensity of existing interfacial bonding at fiber/matrix interface and scanning electron microscopy imaging for visual characterization. The results show that TPU composites have significantly higher abrasion resistance and slip resistance on ice as compared to SBS composites with the maximum abrasive resistance index (347.5 ± 29.5, p < 0.0001) and coefficient of friction on ice (0.375 ± 0.031, p < 0.0001) for PBO/TPU composite. Similarly, Fourier tranorm infrared spectroscopy spectrum demonstrates stronger existing bands in TPU compared to SBS composites indicative of better fiber wetting in TPU composites. The current PBO–TPU composite can be a potential candidate for various antislip applications as it has improved wear‐resistance (22%) and slip‐resistance (57%) properties, with respect to pure TPU.

The ability to control material properties in space and time for functionally graded viscoelastic materials makes them an asset where they can be adapted to different design requirements. The continuous microstructure makes them advantageous over conventional composite materials. Functionally graded porous structures have the added advantage over conventional functionally graded materials of offering a significant weight reduction compared to a minor drop in strength. Functionally graded porous structures of acrylonitrile butadiene styrene (ABS) had been fabricated with a solid‐state constrained foaming process. Correlating the microstructure to material properties requires a deterministic analysis of the cellular structure. This is accomplished by analyzing the scanning electron microscopy images with a locally adaptive image threshold technique based on variational energy minimization. This characterization technique of the cellular morphology is analyst independent and works very well for porous structures. Inferences are drawn from the effect of processing on microstructure and then correlated to creep strain and creep compliance. Creep is strongly correlated to porosity and pore sizes but more associated to the size than to porosity. The results show the potential of controlling the cellular morphology and hence tailoring creep strain/compliance of ABS to some desired values. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 795–803

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Fiber debonding and pullout are well-understood processes that occur during damage and failure events in composite materials. In this study, we show how these mechanisms, under controlled conditions, can be used to produce multifunctional textured surfaces. A two-step process consisting of (1) achieving longitudinal fiber alignment followed by (2) cutting, rearranging, and joining is used to produce the textured surfaces. This process employs common composite manufacturing techniques and uses no reactive chemicals or wet handling, making it suitable for scalability. This uniform textured surface is due to the fiber debonding and pullout occurring during the cutting process. Using well-established fracture mechanics principles for composite materials, we demonstrate how different material parameters such as fiber geometry, fiber and matrix stiffness and strength, and interface behavior can be used to achieve multifunctional textured surfaces. The resulting textured surfaces show very high friction coefficients on wet ice (9× improvement), indicating their promising potential as materials for ice traction/tribology. Furthermore, the texturing enhances the surface's hydrophobicity as indicated by an increase in the contact angle of water by 30%. The substantial improvements to surface tribology and hydrophobicity make fiber debonding and pullout an effective, simple, and scalable method of producing multifunctional textured surfaces.

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Adaptive properties and complex shapes of modern day soft matter components create a challenge for materials applications where mechanical properties of intricate fabricated components cannot be determined from conventional invasive and destructive mechanical tests. In particular, challenges arising from variable mechanical properties of polydimethylsiloxanes (PDMSs) constantly attract wide‐scale attention in the fields of material sciences, biological systems, and microfluidics. Herein, a noninvasive and nondestructive strain‐induced infrared spectroscopic method (S‐FTIR) is developed. S‐FTIR is a method that maps thermo‐mechanical response of PDMS to its strain‐induced spectral fingerprint. From the results of this study, strong correlations of up to 95% between spectral fingerprint of PDMS and its corresponding nonlinear thermo‐mechanical response is seen. Given the nature of these results, it is expected that S‐FTIR will provide an interesting new analytical approach to understand soft materials and allow for the characterization of micro and nanoscale devices composed of these polymeric materials as well. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 359–367

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