Interfacial properties of regenerated cellulose fiber/polystyrene composite materials. Effect of the coupling agent's structure on the micromechanical behavior

The interfacial properties of polystyrene/regenerate cellulose fiber compos ite materials are characterized using micromechanical tests such as the sin gle fiber fragmentation and microbond ("microdrop test"). The cellulose fib ers were grafted with different copolymers of different chemical structures as well as different molar masses ranging from 300 to 18,000 (ASA, jeffiso cyanate, commercial poly(styrene-co-maleic anhydride) and "home-made" poly( styrene-co-TMI)). The two polystyrene based copolymers have been shown to b e miscible with polystyrene. It was found that the higher improvement of th e interfacial shear strength was obtained when the fiber is grafted with th e higher molecular weight, i.e., the poly(styrene-co-TMI).