The residual weights of the composite films beyond 500 C increase slightly
with increasing cellulose and lignin content in the composite films.
The maximum decomposition temperature of the RC (Tmax =
326 C) is lower than that of pure cellulose (Tmax = 345 C). This result
suggested that the strong intra- and inter-molecular hydrogen
bonds of cellulose were partially broken by IL during the solution
process, which is coincident with the result of the X-ray diffraction.