Effect of Coupling Agent on the Properties of Polymer/Date Pits Composites

Abstract

The morphology of the fracture surfaces of polymer/date pits composites was investigated. Polymers used in this study were high density polyethylene (HDPE) and polystyrene (PS). Date pits in the form of granules were two types of date pits: khlaas (K) and sekari (S). Two coupling agents, diphenylmethane-4 4 -diisocyanate (DPMI) and ethylene propylene grafted with malice anhydride (EP-g-MA), were used to ease the incorporation of date pit particles into polymer matrix. The SEM micrographs of the neat composites, that is, with no coupling agents, showed coarse morphology with bad dispersion, adhesion, and distribution of date pit particles within the polymer matrix. On the other hand, PS100/K composites coupled with DPMI and EP-g-MA had reasonable dispersed phase size with good distribution and adhesion to the composite matrix which in turn improve the mechanical properties of the resulted polymer/date pits composites.

Influence of coupling agent on altering the reinforcing efficiency of natural fibre-incorporated polymers – A review

“…In the case of HDPE, MA could be replaced with isocyanate and the performance is compared, which is found to be low. 135 On the average, 26% of increment is observed (Tables 4 and 5) in mechanical properties on the addition of MA as a CA. MA seems superior to isocyanate in improving mechanical properties.…”

“…Alsewailem and Bindkhder 135 studied the influence of diphenylmethane-4 4′-diisocyanate (DPMI) and ethylene-propylene grafted with maleic anhydride (EP-g-MA) CAs on composites of high-density polyethylene (HDPE)/date pits and PS/date pits. The composite with concentration of 5 wt% DPMI shows a slight increase in izod impact strength (IIS), but the tensile strength decreases by a small amount.…”

“…SEM micrographs: (a) polystyrene/date pits (70%/30%) without CA and (b) polystyrene/date pits (70%/30%) with 17% EP-g-MA as CA. 135 …”

“…SPM micrographs describing the finer distribution of date pits in polystyrene on addition of CA. 135 …”

“…161 For styrene polymer compounds, CA like polybutadiene and isocyanate are preferred. 135,166 Some results show the reduction of mechanical properties even after the addition of CA along with natural fibre to matrix. This could be justified with fibre loading percentage, improper mixing, and excess/insufficient dosage of CA.…”