Fracture and impact energy absorption characteristics of PMMA-PU transparent interpenetrating polymer networks
Hareesh Tippur (Auburn University), Kailash Jajam (Auburn University)
Eringen Medal Symposium in honor of G. Ravichandran
Wed 10:45 - 12:15
Salomon 001
In this work, Interpenetrating Polymer Networks (IPNs) have been synthesized for potential structural and transparent armor applications. Poly(methyl methacrylate) (PMMA) is used as the stiff phase and polyurethane (PU) as the tough phase. Several IPN compositions with different PMMA:PU ratios in the range of 90:10 to 70:30 are formulated by carefully controlling process kinetics to achieve optical transparency. Dynamic fracture tests on IPNs are conducted using long-bar impactor setup in conjunction with digital image correlation method and high-speed photography. The results are studied relative to fracture responses under quasi-static loading conditions. Low-velocity impact studies of IPNs are also performed using a falling dart apparatus. Fracture and low-velocity impact experiments show that an optimum range of PMMA:PU ratios produce enhancement of dynamic crack initiation fracture toughness and impact energy absorption capability when compared to PMMA. Fracture surface morphology and macro scale damage features reveal distinct failure modes in different IPN compositions.