Thermoplastic elastomers
are considered the fastest-growing elastomers
in recent years because of their thermomechanical recyclability, in
contrast to traditional thermoset rubbers. Polyolefins such as low-density
polyethylene (LDPE) show low mechanical properties, particularly poor
elongation when compared with an elastomer or rubber. In this study,
LDPE resin is converted to highly ductile rubber-like materials with
high elongation and low modulus properties on blending with polyisoprene
rubber (IR), followed by treating with dicumyl peroxide as a curing
agent and organosolv lignin as an additive. The technique of high
shear melt-mixing, in conjunction with vulcanization or crosslinking
using organic peroxide, is used to develop hybrid materials based
on the LDPE/IR blend at a 70/30 mass ratio, where LDPE is replaced
partly with lignin. Various characteristics such as tensile, viscoelasticity,
melt flow, crystallinity, and phase morphology of the materials are
analyzed. As expected, vulcanization with peroxide can improve the
mechanical performance of the LDPE/IR blends, which is further improved
with the application of lignin (2 to 5 wt. %), particularly tensile
strain is profoundly increased. For example, the average values of
the tensile strength, the modulus, and the ultimate elongation of
neat LDPE resin are 7.8 MPa, 177 MPa, and 62%, respectively, and those
of LDPE/IR/lignin/DCP 65/30/05/2 are 8.1 MPa, 95 MPa, and 238%, respectively.
It indicates that the application of lignin/DCP has a profound effect
on improving the ductility and elastomeric characteristics of the
materials; thus, this material can have the potential to replace traditional
rubber products.