Fabrication and microstructural characterization of functionally graded porous acrylonitrile butadiene styrene and the effect of cellular morphology on creep behavior

Abstract

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

Double-layer membrane cathode with improved oxygen diffusivity in zinc-air batteries

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Relation of impact strength to the microstructure of functionally graded porous structures of acrylonitrile butadiene styrene (ABS) foamed by thermally activated microspheres

“…Densities of the porous structures were measured by the density determination Kit as explained in section 2. SEM measurements for porosity were carried out with local thresholding that binarizes the SEM image and then calculate the ratio of white regions (pores) to black region (solid material) [1]. Experimental data were favoured whenever there was a mismatch with SEM images analysis and then pores' diameters were measured manually with ImageJ software.…”

“…Functionally graded porous structures can offer significant weight reduction comparable to that offered by homogeneous porous structures while maintaining tailorable strength compared to the solid precursors [1]. One of the attractive applications of polymers is impact resistance and energy absorption due to their viscoelastic nature that helps in dissipating energy in addition to their light weight compared to metals and ceramics.…”

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Analysis and homogenization of functionally graded viscoelastic porous structures with a higher order plate theory and statistical based model of cellular distribution

“…This in turn makes the homogenization procedure combined with the accurate HSDT very valuable tool for conducting numerical experiments to design FG porous structures. In a previous work of the authors [65], the creep compliance of FG acrylonitrile butadiene styrene (ABS) was successfully correlated to the microstructure. Property-structure and processing graphs have been established for the FG porous ABS from experimental data.…”