scholarly journals Protection of Petroleum Pipeline Carbon Steel Alloys with New Modified Core-Shell Magnetite Nanogel against Corrosion in Acidic Medium

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Gamal A. El Mahdy ◽  
Ayman M. Atta ◽  
Amro K. F. Dyab ◽  
Hamad A. Al-Lohedan
Keyword(s):  
Carbon Steel ◽  
Sulfonic Acid ◽  
Electrochemical Impedance ◽  
Electrochemical Techniques ◽  
Core Shell ◽  
Magnetite Nanoparticle ◽  
Potassium Peroxydisulfate ◽  
Redox Initiator ◽  
Initiator System ◽  
First Time

New method was used to prepare magnetite nanoparticle based on reduction of Fe(III) ions with potassium iodide to produce Fe3O4nanoparticle. The prepared magnetite was stabilized with cross-linked polymer based on 2-acrylamido-2-methylpropane sulfonic acid (AMPS to prepare novel core-shell nanogel. In this respect, Fe3O4/poly(2-acrylamido-2-methylpropane sulfonic acid) (PAMPS) magnetic nanogels with controllable particle size produced via free aqueous polymerization at 65°C have been developed for the first time. The polymer was crosslinked in the presence of N,N-methylenebisacrylamide (MBA) as a crosslinker and potassium peroxydisulfate (KPS) as redox initiator system. The structure and morphology of the magnetic nanogel were characterized by Fourier transform infrared spectroscopy (FTIR) and transmission and scanning electron microscopy (TEM and SEM). The effectiveness of the synthesized compounds as corrosion inhibitors for carbon steel in 1 M HCl was investigated by various electrochemical techniques such as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results showed enhancement in inhibition efficiencies with increasing the inhibitor concentrations. The results showed that the nanogel particles act as mixed inhibitors. EIS data revealed thatRctincreases with increasing inhibitor concentration.

Abrasive-Free Polishing of Hard Disk Substrate with H2O2-K2S2O8-NaHSO3 Slurry

2013 ◽  
Vol 690-693 ◽  
pp. 3209-3212 ◽  
Author(s):  
Wei Tao Zhang ◽  
Hong Lei
Keyword(s):  
Removal Rate ◽  
Hard Disk ◽  
Corrosion Current ◽  
Polarization Measurement ◽  
Resonance Spectroscopy ◽  
Hydroxyl Free Radical ◽  
Potassium Peroxydisulfate ◽  
Hard Disk Substrate ◽  
Initiator System ◽  
Disk Substrate

The effect of potassium peroxydisulfate-sodium hydrogensulfite (K2S2O8- NaHSO3) as an initiator system in H2O2 –based slurry for the abrasive-free polishing (AFP) of hard disk substrate was investigated. The polishing experimental results showed that the H2O2-K2S2O8-NaHSO3 slurry had ten times higher material removal rate (MRR) than the H2O2 slurry in AFP of the hard disk. Further, the polishing mechanism of H2O2-K2S2O8-NaHSO3 slurry was investigated. Compared with the H2O2 slurry, electron spin-resonance spectroscopy (EPR) analysis showed that the H2O2-K2S2O8-NaHSO3 slurry provides twenty times higher concentration of hydroxyl free radical. Potentiodynamic polarization measurement showed that the corrosion current of disk substrate in the H2O2-K2S2O8-NaHSO3 slurry is larger than that in the H2O2 slurry. The results imply that K2S2O8-NaHSO3 as an initiator system for H2O2–based slurry has application prospects in abrasive-free polishing.

ChemInform Abstract: KINETICS AND MECHANISM OF THE INTERACTION OF POTASSIUM PEROXYDISULFATE AND 18-CROWN-6 IN AQUEOUS MEDIA

1984 ◽  
Vol 15 (7) ◽  
Author(s):  
J. K. RASMUSSEN ◽  
S. M. HEILMANN ◽  
P. E. TOREN ◽  
A. V. POCIUS ◽  
T. A. KOTNOUR
Keyword(s):  
Aqueous Media ◽  
Kinetics And Mechanism ◽  
Potassium Peroxydisulfate

Structure and Properties of Chitosan Containing Polyacrylic Acid Hydrogel Grafted SMS Nonwovens

2009 ◽  
Vol 87-88 ◽  
pp. 513-517 ◽  
Author(s):  
Xu Pin Zhuang ◽  
Wen Jian Deng ◽  
Bo Wen Cheng
Keyword(s):  
Wound Healing ◽  
Antibacterial Activity ◽  
Acrylic Acid ◽  
Water Absorption ◽  
Ammonium Nitrate ◽  
Polyacrylic Acid ◽  
Structure And Properties ◽  
Second Stage ◽  
Xps Spectroscopy ◽  
Potassium Peroxydisulfate

Hydrogels donate moisture to dehydrated tissue and absorb some moisture and accepted in wound healing. Polypropylene (PP) SMS nonwovens were grafted polyacrylic acid (PAA) hydrogel technique contanining chitosan to enhance hydrophilicity and antibacterial activity. In the first stage, nonwovens were hydroxylated by treatment with aqueous potassium peroxydisulfate solution under a strong flow of nitrogen. In the second stage, the hydroxylated nonwovens were subjected to grafting of acrylic acid using cerric ammonium nitrate as an initiator. Subsequently, chitosan was grafted onto the modified NWs with N,N'-Methylenebisacrylamide. The modified nonwovens were characterized by XPS spectroscopy and SEM, the results showed that acrylic acid was copolymerized and hydrogel grafted onto SMS nonwovens. Hydrogel grafted nonwovens exhibited enhanced wettability and water absorption ability. With introduce of chitosan further, the modified NWs exhibited effectively antibacterial activity against E.coli.

Sign in / Sign up

Export Citation Format

Share Document