Effect of poly(acrylic acid) and poly(vinyl alcohol) on the solubility of colloidal BaTiO3 in an aqueous medium

2003 ◽  
Vol 18 (5) ◽  
pp. 1266-1274 ◽  
Author(s):  
Ungyu Paik ◽  
Vincent A. Hackley ◽  
Jaeho Lee ◽  
Sangkyu Lee

The influence of poly(acrylic acid) (PAA) and poly(vinyl alcohol) (PVA) on Ba dissolution from the BaTiO3-aqueous solution interface was investigated. Incongruent dissolution of Ba impacts the colloidal stability, microstructure, and electrical properties of BaTiO3 and related perovskite dielectric materials used in the manufacture of ceramic capacitors. The solubility characteristics of BaTiO3 were influenced significantly by the presence of PAA and PVA. PAA, which forms weak monodentate complexes with Ba2+, acted as both a passivating and a sequestering agent, depending on pH. Both PAA and PVA provided some degree of passivation in the acidic pH region. Above pH 8, where BaTiO3 solubility decreases sharply, PVA had a moderate passivating effect, whereas solubility was enhanced by PAA with a positive linear dependence on concentration. The adsorptive and electrokinetic behavior of colloidal BaTiO3 with respect to PAA and PVA are correlated with the observed passivating and sequestering properties of these polymers.

2020 ◽  
Vol 35 (3) ◽  
pp. 203-215
Author(s):  
Mehmet Emin Diken ◽  
Berna Koçer Kizilduman ◽  
Begümhan Yilmaz Kardaş ◽  
Enes Emre Doğan ◽  
Mehmet Doğan ◽  
...  

The nanocomposite hydrogels were prepared by dispersing of the nanopomegranate seed particles into poly(vinyl alcohol)/poly(acrylic acid) blend matrix in an aqueous medium by the solvent casting method. These hydrogels were characterized using scanning electron microscopy, Fourier transform infrared spectra, differential scanning calorimetry, and optical contact angle instruments. The nanopomegranate seed, blend, and hydrogel nanocomposites were tested for microbial activity. In addition, cytocompatibilities of these blend and hydrogel nanocomposites/composites were tested on human lymphocyte with in vitro MTS cell viability assays. Fourier transform infrared spectra revealed that esterification reaction took place among functional groups in the structure of poly(vinyl alcohol) and poly(acrylic acid). The hydrophilic properties of all hydrogels decreased with increasing nanopomegranate seed content. The mean diameters of the nanopomegranate seed particles were about 88 nm. Nanopomegranate seed particles demonstrated antibacterial properties against gram-positive bacteria, Staphylococcus aureus, and gram-negative bacteria, Escherichia coli. The lymphocyte viabilities increased after addition of nanopomegranate seeds into the polymer blend. The swelling behavior of blend and hydrogels was dependent on the cross-linking density created by the reaction between poly(vinyl alcohol)/poly(acrylic acid) blend and nanopomegranate seed. Scanning electron microscopy images were highly consistent with Fourier transform infrared spectra, differential scanning calorimetry, and antibacterial activity results.


Nanoscale ◽  
2013 ◽  
Vol 5 (23) ◽  
pp. 11464 ◽  
Author(s):  
Ji Liu ◽  
Christophe Detrembleur ◽  
Antoine Debuigne ◽  
Marie-Claire De Pauw-Gillet ◽  
Stéphane Mornet ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document