The TGA studies of the PANI(DBSA)/PVA blend films are
performed in the range of 30–700 _C at a heating rate of
10 _C/min (as shown in Fig. 5 and summarised in Table 4)
under an inert atmosphere. The TGA thermogram exhibits
the following results: pure PVA, PANI and PANI(DBSA)/
PVA blend exhibit weight loss in one step, three steps, and four
steps, respectively. In pure PVA, the polymer backbone is
stable up to 200 _C, with the polymer degradation commencing
near 220 _C and completing at 320 _C. In the case of pure
PANI and its blends, the 1st step of weight loss is found to be
between 40 and 140 _C for PANI and between 40 and 110 _C
for PANI(DBSA)/PVA blend; this first step of weight loss is
caused by moisture, free acids and unreacted monomer, which
are used as solvents and dopants in the preparation of the PANI.