Abstract:
In recent years, attention has been focused on elastomeric polymers as a potential retrofitting
material considering their capability in contributing towards the impact resistance of various
structural elements. A comprehensive understanding of the behavior and the morphology of
this material are essential to propose an effective and feasible alternative to existing structural
strengthening and retrofitting materials. This article presents the findings obtained from a series
of experimental investigations to characterize the physical, mechanical, chemical and thermal
behavior of eight types of palm-based polyurethane (PU) elastomers, which were synthesized from
the reaction between palm kernel oil-based monoester polyol (PKO-p) and 4,4-diphenylmethane
diisocyanate (MDI) with polyethylene glycol (PEG) as the plasticizer via pre-polymerization. Fourier
transform infrared (FT-IR) spectroscopy analysis was conducted to examine the functional groups
in PU systems. Mechanical and physical behavior was studied with focus on elongation, stresses,
modulus, energy absorption and dissipation, and load dispersion capacities by conducting hardness,
tensile, flexural, Izod impact, and differential scanning calorimetry tests. Experimental results
suggest that the palm-based PU has positive effects as a strengthening and retrofitting material
against dynamic impulsive loadings both in terms of energy absorption and dissipation, and load
dispersion. In addition, among all PUs with different plasticizer contents, PU2 to PU8 (which contain
2% to 8% (w/w) PEG with respect to PKO-p content) show the best correlation with mechanical
response under quasi-static conditions focusing on energy absorption and dissipation and load
dispersion characteristics.
