Temperature of dynamic absorption peak T(E max) due to micro - Brownian motion of segments of polystyrene, SBR or polybutadiene filled with carbon black, a well-known active reinforcing filler, is higher than that of the corresponding unfilled polymer. On the other hand, calcium carbonate, a typical inert filler, does not alter the rheological properties of polymers in the composite systems. Therefore the shift in T (E max) must be representing the extent of interaction between the two materials. Cellulose, lignin and xylan elevate T(E max) of the filled systems, and therefore we know that they are immobililizing the polymer molecules near by. Among the three wood components studied, xylan is the most active as a filler.