Abstracts Book - IMRC 2018

• SB1-O030 Invited Talk
TERNARY POLYMER COMPOSITES EXHIBITING BULK AND
SURFACE QUADRUPLE SHAPE MEMORY BEHAVIOR
Patrick Mather 1 , Shelby Buffington 2
1 Bucknell University, Chemical Engineering, United States. 2 Syracuse University, Biomedical and
Chemical Engineering, United States.
Shape memory polymers are an exciting class of smart materials exhibiting a
variety of thermomechanical phenomena that range environmentally triggered
shape change to reversible actuation and even thermal mending of damage.
Here, we describe the design of a multiphase quadruple shape memory
composite capable of switching between four programmed shapes: three
temporary and one permanent. We combined two previously reported
fabrication methods by embedding an electrospun mat of a thermoplastic fibers
(polycaprolactone, PCL) with a matrix solution of epoxy monomers featuring
dissolved poly(methyl methacrylate), or PMMA. As epoxy polymerization ensued
this two-component matrix underwent phase separation into epoxy-rich and
PMMA-rich phases. This created a ternary composite featuring a co-continuous
network of PCL fibers and a matrix composed of both epoxy and PMMA with a
complex morphology. The resulting composite demonstrated three separate
thermal transitions: glass transitions for epoxy and PMMA and a melting
transition for PCL. We will demonstrated that each engendered an ability to
mechanically program (or “fix”) independent temporary shapes while a forth,
permanent shape was prescribed by the geometry used during sample cure. In
addition, quadruple surface shape memory capability was exhibited by the new
material. The versatility of this approach enables a large degree of design
flexibility for multi-shape memory materials.
Acknowledgment:
Partial support the NSF IGERT (DOE-1068780) and NSF DMREF (1334658) are
gratefully acknowledged.
Keywords: Shape memory, Electropinning, Phase Separation
Presenting authors email: patrick.mather@bucknell.edu