CELLULOSE-POLYAMIDE-66 BLENDS .2. MECHANICAL-BEHAVIOR

Blends of the natural polymer cellulose with a synthetic polymer, poly amide 66, are studied in order to determine if the expected strong int eraction between them, due to hydrogen bonds, could improve their mech anical properties such as strength and elongation at break. In a previ ous work [Part I, J. Polym. Sci. Polym. Phys., 32, 1437 (1994)], the p reparation technique and the characterization of cellulose-polyamide 6 6 (PA66) blends were described in detail. Several samples in the compo sition range between 0 to 70 wt % of PA66 were carefully dried and exa mined using dynamic mechanical and tensile tests. Based on previous wo rk a new percolation model has been developed. It takes both linear an d nonlinear mechanical behaviors into account and allows for the effec t of adhesion between material domains. From comparison between experi mental and predicted data, it is concluded that a partial miscibility between the amorphous phases of cellulose and PA66 exists and is respo nsible for a strong adhesion at their interface. Solid-state C-13 nucl ear magnetic resonance has also been used to study these samples and s upports the existence of strong interactions between both homopolymers . (C) 1995 John Wiley & Sons, Inc.