Cellulose fibers/polyethylene hybrid composites: Effect of long chain organic acid cellulose esters and organic peroxide on rheology and tensile properties

Composites were prepared by compounding linear low-density polyethylene (LLDPE) with cellulose fibers as reinforcing filler. Effect of a small addition of unsaturated or saturated long chain organic acid cellulose esters (cellulose undecylenate, undecanoate, oleate, stearate) with partial degrees of substitution and the presence of dicumyl peroxide (DCP) as a polymer crosslinking initiator was investigated on the rheological and tensile properties of hybrid composites. No grafting o f polyethylene onto fibers surfaces occurred under processing conditions; however composites with DCP showed significant increase in tensile properties. The use of unsaturated cellulose esters in composites containing DCP was more effective in maintaining stress at yield and in progressive increase of energy to yield with higher cellulose esters content and degree of substitution in comparison with composites containing only cellulose fibers. The tensile properties decreased sharply in composites containing saturated cellulose esters.