24-10-2012, 10:50 AM
Reactive and Nonreactive Binders in Glass/Vinyl Ester Composites
ABSTRACT
This study characterizes and evaluates two types of preform binders reactive thermosets and nonreactive thermoplastics.
The interply adhesion between woven glass plies was measured as a function of binder type, concentration, and preforming
conditions. It was found that reactive binders offer the potential to provide much larger interply adhesions between glass plies
in a preform than thermoplastics and are thus superior choices for the fabrication of complex-shaped preforms requiring little
or no springback. Laminated composite panels fabricated from preforms with varying binder concentrations were evaluated
in regards to their interlaminar properties. It was found that both binder types degraded the interlaminar shear strength of a
woven glass reinforced/vinyl ester composite. Additionally, composite laminates made from preforms and containing the
thermoplastic binder showed decreases in the interlaminar fracture toughness of the composite by ^60%. However, composite
laminates fabricated from preforms using the reactive epoxy binder showed an increase in fracture toughness by ^47%. Hence,
it is concluded that a range of interlaminar properties can be achieved depending on the type of binder, the amount of binder,
and the processing of the binder, and also that of the composite itself.