**3.4.2.4 Thermogravimetric analysis(TGA)**

Thermogravimetric analysis (TGA) for the electrochemically prepared POCP and POHP samples have been investigated and the TGA-curve is represented in Figure 13 (a and b).

The TGA steps of the prepared POCP are shown in Fig 13(a) from which it is shown that there are three stages during thermolysis of the POCP sample

The first stage : including the loss of 2H2O molecules in the temperature range between 25oC and 120oC , The weight loss was found to be (5.30%) which is in good agreement with the calculated value (5.70%)this is in good agreement with what was found in the literature for water release [Sayyah et al 2010].

second stage: includes the loss of the dopant species , SO3 and one benzenoide ring in the temperature range between 120 oC and 400oC , the weight loss for this step was found to be 24.04% which is in good agreement with the calculated value (24.8%)

The third stage: in the range of temperature >490 oC, the remaining part of the polymer decomposition,is equal to 70.70. The found data equal to 69.5.

 The TGA steps of the prepared POHP are shown in Fig. 13 (b) from which it is shown that there are four stages during thermolysis of the polymer sample

The first stage: including the loss of 2H2O molecules in the temperature range between 25 oC and 100oC , The weight loss was found to be(4.35%) which is in good agreement with the calculated value(4.6%) .

Electropolymerization of Some Ortho-Substituted Phenol Derivatives on Pt-Electrode from

shows that the prepared polymers are amorphous as shown in Figure 14 (a and b).

Fig. 14. XRD and SEM of POCP and POHP adhere Pt surfaces.

**3.4.2.5 Surface morphology study** 

(c and d)).

Aqueous Acidic Solution; Kinetics, Mechanism, Electrochemical Studies and Characterization of… 41

In most conditions, a homogeneous, smooth and well-adhering brown POCP or black POHP films were electrodeposited on platinum electrode surfaces. The X-ray diffraction pattern

The surface morphology of the polymers obtained at the optimum conditions was examined by scanning electron microscopy. The SEM micrographs show a smooth lamellar surface feature of POCP and a smooth feature with uniform thickness for POHP (c.f., Fig 14
