The aim of this work
is to develop a biobased functional reactive
diluent for thermosetting epoxy resins suitable for high-performance
applications. An advanced organosilicon-grafted cardanol novolac epoxy
resin (SCNER) was synthesized from cardanol novolac epoxy resin and
heptamethyltrisiloxane. After the chemical structure of SCNER was
identified by Fourier transform infrared,
1
H NMR, and
13
C NMR, it was used to modify the diglycidyl ether of the
bisphenol A (DGEBA)/methylhexahydrophthalic anhydride system. The
SCNER showed unique advantages, reducing the viscosity of DGEBA and
improving the properties of the cured resin. With 10 wt % SCNER, the
cured resin exhibited a higher tensile strength (78.84 MPa) and impact
strength (32.36 kJ·m
–2
). The single glass transition
temperature (
T
g
) step proved the homogeneous
phase structure of the cured resin. Inevitably, the
T
g
of the cured resin decreased for the addition of SCNER.
The dynamic mechanical analysis results indicated that the storage
modulus of the cured resin decreased with the increasing content of
SCNER. The morphology showing the ductile fracture of the cured resin
was testified by scanning electron microscopy. The dilution and toughening
properties of SCNER paves the way to a wide range of possible “eco-friendly”
applications, especially in the fields of coatings, paintings, and
adhesives.