Multi-walled carbon nanotube (MWCNT) reinforced epoxy films were deposited on an aluminum substrate by a hot-pressing process. Three-point bending tests were performed to determine the Young's modulus of MWCNT reinforced nanocomposite films. Compared to the neat epoxy film, nanocomposite film with 1 wt % of MWCNT exhibits an increase of 21% in the Young's modulus. Four-point-bending tests were ...

a poly(lactic acid) (pla) based nanocomposite active packaging has been developed for the controlled release of tert-butylhydroquinone (tbhq) antioxidant. pla based active films were loaded with tbhq (3%wt) or mixture of modified cellulose nanofiber (mcnf) (8%wt) and tbhq (3%wt) to obtain active and nanocomposite active films, respectively. release studies indicated that the release rate of tbh...

We investigate the time-scale invariant changes in electromagnetic and mechanical energy releases prior to a rock failure or a large earthquake. The energy release processes are caused by damage evolutions such as crack propagation, motion of charged dislocation, area-enlargement of sheared asperities and repetitive creep-rate changes. Damage mechanics can be used to represent the time-scale in...

The objective of this paper is to provide a fracture mechanics characterization mortar nanocomposites reinforced with multiwall carbon nanotubes (MWCNTs). critical stress intensity factor, KIc, the strain energy release rate, GIc, effective crack length, ac, and tip opening displacement, CTODc are determined using three-point bend specimens. It was established that reinforcement MWCNTs provides...

Shapeshifting enables a wide range of engineering and biomedical applications, but until now transformations have required external triggers. This prerequisite limits viability in closed or inert systems and puts forward the challenge of developing materials with intrinsically encoded shape evolution. Herein we demonstrate programmable shape-memory materials that perform a sequence of encoded a...

Delamination of residually stressed thin film strips is analyzed to expose the dependence on strip width and filmysubstrate elastic mismatch. Isotropic films and substrates are assumed. The residual stress in the film is tensile and assumed to originate from mismatch due to thermal expansion or epitaxial deposition. Full and partial delamination modes are explored. In full delamination, the int...

We have carried out systematic fracture experiments in a single edge notch geometry over a range of stretch rates on dual crosslink hydrogels made from polyvinyl alcohol chains chemically crosslinked with glutaraldehyde and physically crosslinked with borate ions. If the energy release rate necessary for crack propagation was calculated conventionally, by using the work done to deform the sampl...