Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Poly vinyl alcohol


Thermogravimetric Analysis on PVA / PVP Blend Under Air Atmosphere

Nadia Azeez Betti

Engineering and Technology Journal, 2016, Volume 34, Issue 13, Pages 2433-2442
DOI: 10.30684/etj.34.13A.6

Films of poly vinyl alcohol (PVA) /poly vinyl pyrrolidone (PVP) blends have been prepared by solution casting method with different ratios of each other (100/0 , 80/20 , 60/40 , 50/50 , 40/60 , 20/80 , 0/100) to investigate their thermal stability comparing to correspondent pure polymers by using thermogravimetric analysis (TGA) under air atmosphere. It was found that PVA and PVP films show two decomposition steps while PVA/PVP blend films show three decomposition steps except the film of the ratio (20/80) that shows four decomposition steps .It was also found that blending decreases the temperature ranges at which the first and the second decomposition steps of PVA and PVP occur. It was found that blending PVA with PVP has significant effect on weight loss at first decomposition step of PVA by increasing it as the ratio of PVP increases. It was also found that blending PVA with PVP has significant effect on weight loss at second decomposition step of PVA by decreasing it as the ratio of PVP increases. It was found that the weight loss at third decomposition step of PVA/PVP blend films increases as the ratio of PVP increases . According to TGA thermograms under air atmosphere, PVA , PVP and PVA/PVP blend films show almost the same total weight loss which means of same thermal stability.

The Effect of Cesium Chloride on Thermal Properties of Poly (Vinyl Alcohol)

Nadia Azeez Betti

Engineering and Technology Journal, 2016, Volume 34, Issue 12, Pages 2193-2206
DOI: 10.30684/etj.34.12A.3

Poly (vinyl alcohol), PVA for short, films doped with different concentrations of cesium chloride(CsCl) (0% , 2% , 4% , 6% , 8% , 10% , 12% , 14% ,16% ) were prepared by solution casting method to study the effect of this salt on thermal properties of PVA by using thermogravimetric analysis (TGA) .It was found that the dopedPVA films with concentrations(14% and 16%) of CsCl aremore thermal stable than PVA while doped PVAfilms with concentrations ( 4% and 6%) of CsCl are less thermal stable than PVA and the dopedPVA films with concentration of ( 2% , 8% , 10% and 12%) are almost as thermal stable as PVA. Fourier transform infrared spectroscopy (FTIR) was also used to investigate complexation between CsCl and PVA and was foundthat the doped PVA films with concentration (2% , 4% , 6% and 8%) of CsClshowno significant shifts in wave numbers of the characteristic bands of PVA while doped PVA films with concentrations (10%, 12% ,14% and 16% ) of CsClshow a significant shifts to a higher values in wave number of stretching vibration of (-OH) comparing to PVA indicating well complexation between CsCl and PVA.