Tga 209

The apparent zeta potential was measured using a Malvern Zetasizer Nano ZS (M3-PALS) using the Non-Invasive Back Scatter technique. The instrument was equipped with a monochromatic red laser operating at 632.8 nm and the data were analysed with the Malvern Dispersion technology software. Z-average values for three measurements were recorded. The Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) measurements were done using a Netzsch TGA 209 in the temperature range 0 to 800 ^oC with an increment of 30 K/10 minutes in a N₂ atmosphere. Scanning electron microscopy (SEM) analysis was carried out using Tescan, Vega 3 LMU with Oxford EDX detector (Inca XmaW20) SEM. The sample was deposited on a carbon film for SEM analysis. Transmission electron microscopy (TEM) measurement was carried out with a JEOL 2200FS double aberration corrected FEG microscope, operating at 200 kV. TEM samples were prepared by casting a drop of the nanoparticle suspension onto copper grids covered with holey carbon films. The X-Ray Diffraction (XRD) data were recorded using a Bruker d8 discover X-Ray diffractometer equipped with Cu-Kα radiation (λ = 1.5405 Å). The monochromator used was Johansson Type. The step size was 0.02 degree and the scan rate was 20 s per step.

Using a JASCO V-570 UV–VIS–NIR spectrophotometer, the UV-visible absorption spectra were measured at room temperature. A Bruker d8 discover X-Ray diffractometer equipped with Cu-Kα radiation (λ = 1.5405 Å) was used to collect X-Ray diffraction (XRD) data. In this case the monochromater was Johansson Type. Jobin-Yvon-Horiba Fluor log III fluorimeter (with a 100 W Xenon lamp as excitation source and R-928 operating at a voltage of 950 V as detector) was applied to measure emission and excitation fluorescence spectra where the resolution increment was 1 nm and slit was kept 5 nm. Data were analyzed using Fluorescence program. For measuring resonance Rayleigh scattering, synchronous fluorescence scan was applied in the same instrument but in this mode the excitation and emission wavelength interval (Δλ) was kept at 0 nm. Using a Netzsch TGA 209 in the temperature range 30 °C to 1000 °C with an increment of 10 K/min in a N₂ atmosphere, all the thermogravimetric Analysis (TGA) was carried out. SEM analysis was made using Tuscan. Ultracentrifugation technique was used for separation and washing the samples.

TGA measurements were carried out on TGA 209 (NETZSCH, Selb, Germany) with temperature ranging from −25 °C to 700 °C and the heating rate was 20 °C·min⁻¹. Derivative thermogravimetry, DTG, is the change in weight of the sample with respect to time, dα/dt. The area of the peaks is in proportion to the total change in the sample weight. The DTG curves were obtained by differentiation of the TG curves. Two distinct gradients were obtained from loss weight curve, which had been expect to be associated with the weight loss percentage of polyethylene segments and polyvinyl acetate segments of copolymer respectively. The sample ID of PEVAs was nominated according to the weight contents of VA determined by TGA.