Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 2 of 2

Full-Text Articles in Engineering

Preparation And Characterization Of Tapioca Starch–Poly(Lactic Acid) Nanocomposite Foams By Melt Intercalation Based On Clay Type, Siew-Yoong Lee, Han Chen, Milford Hanna Jan 2008

Preparation And Characterization Of Tapioca Starch–Poly(Lactic Acid) Nanocomposite Foams By Melt Intercalation Based On Clay Type, Siew-Yoong Lee, Han Chen, Milford Hanna

Department of Biological Systems Engineering: Dissertations and Theses

Abstract Tapioca starch (TS), poly(lactic acid) (PLA), and four different organoclays (Cloisite 10A, Cloisite 25A, Cloisite 93A and Cloisite 15A) were used to produce nanocomposite foams by melt-intercalation. Structural, thermal, physical and mechanical properties were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and an Instron universal testing machine, respectively. The first XRD peaks for all four nanocomposite foams, were observed to shift to lower angles, indicating that intercalation occurred. The extent of intercalation depended on the type of organoclay and was exhibited in the sequence of Cloisite 10A > 25A > 93A > 15A. Glass transition temperatures …


An Ebsd Investigation Of Interstitial-Free Steel Subjected To Equal Channel Angular Extrusion, Azdiar A. Gazder, Wenquan Q. Cao, Christopher H.J. Davies, E V. Pereloma Jan 2008

An Ebsd Investigation Of Interstitial-Free Steel Subjected To Equal Channel Angular Extrusion, Azdiar A. Gazder, Wenquan Q. Cao, Christopher H.J. Davies, E V. Pereloma

Faculty of Engineering - Papers (Archive)

The microstructural evolution of interstitial-free (IF) steel subjected to Φ = 90° equal channel angular extrusion (ECAE) for up to 4 passes via routes A, BA, C and up to 8 passes via routes BC was studied using electron back-scattering diffraction (EBSD). Routes BC and BA recorded the smallest grain size and aspect ratios and the largest average misorientation and area fraction of high-angle grain boundaries (HAGBs). During multiple passes, microstructure refinement continues until a convergence in effective subgrain and grain diameters occurs; following which the rate of HAGB formation reduces slightly. The percentage rise …