Phenol-formaldehyde microcapsules with linseed oil as an active agent were produced by applying in situ polymerization method. The anticorrosion and selfhealing efficiency of the synthesized materials were studied. Characteristics of these synthesized capsules were studied by Fourier transform infrared spectroscopy, and surface morphology was analyzed by using scanning electron microscope. Controllable particle size was estimated at different rpm of stirrer and particle size was checked under microscope and also by using particle size analyzer. The anticorrosion performance of encapsulated microcapsules coated with epoxy resin was carried out in 5% NaCl aqueous solution. The effectiveness of linseed oil filled microcapsules was investigated for healing the cracks generated in paint films or coatings. It was found that the cracks were successfully healed when linseed oil was released from ruptured microcapsules. Further, linseed oilhealed area was found to prevent effectively the corrosion of the substrate in immersion studies.

Homo-and copolymers of 2-(N-phthalimido)ethyl methacrylate (NPEMA) and p-chlorophenyl methacrylate (PCPMA) were prepared in N,N-dimethyl formamide (DMF) solution at 70 °C using 2,2-azo-bisisobutyronitrile (AIBN) as initiator. The nano-CdS-doped polymer composite of NPEMA and PCPMA was prepared via in situ technique. The homo-and copolymers of NPEMA and PCPMA were characterized using FT-IR spectroscopy and gel permeation chromatography (GPC). The polymer nano composites were characterized using FT-IR spectroscopy, X-ray diffraction, and transmission electron microscopy. The reactivity ratios (r 1 and r 2 ) were obtained from the various linear graphical methods. The values of r 1 (NPEMA) = 0.55 and r 2 (PCPMA) = 1.30 were found from the same graphical methods. The copolymer microstructures were found from the mean sequence length, run number, and dyad fraction. Thermal behavior of polymers and polymer nano composites under nitrogen atmosphere was studied. The activation energies of neat polymers were varied in the range of 56-85 kJ/mol, while 28-56 kJ/mol energies were found for nano-CdS-doped polymer composites. The thermodynamic parameters of thermal degradation were also obtained. Kinetic and thermodynamic parameters were confirming the stability of the neat polymers than polymer nano composites. The polymers were assessed on different microorganisms for obtaining the antimicrobial properties. Overall, the polymers permit 10-52, 20-58, and 18-56% growth of bacteria, fungi, and yeast, respectively.

No abstract

Protection of oxidizable metals against corrosion has now being intensively investigated, by applying or developing different methods such as coatings and conversion films; however, all reported methods involve environmentally hazardous materials. Conducting polymers have now been used as corrosion inhibitor coatings that are either chemically or electrochemically deposited on the metal substrate. The application of nanotechnology in the corrosion protection of metals has recently gained momentum. Environmental impact can also be improved by utilizing nanostructure particulates in coatings and eliminating the requirement of toxic solvents. We report here the synthesis of nanoparticles of polyaniline (PANI) and poly-o-anisidine (POA) using emulsion polymerization method in micellar solution of SDS and their anticorrosive property has been experimentally checked. The prepared nanoparticles have been characterized by FTIR and TEM. The nanoparticles of the synthesized polymers were dispersed in alkyd paint formulation for coatings on the metal surface (mild steel). The water absorption in the prepared coatings was also studied. The corrosion rate of polymeric film was determined by weight loss measurement and the surface morphology was examined by SEM. The nano PANI/Alkyd coatings showed considerable protection against corrosion than the POA/alkyd coatings.

Polyaniline (PANI) latexes were synthesized by emulsion polymerization using dodecyl benzene sulfonic acid (DBSA) and sodium dodecyl sulfate (SDS) as a surfactant. Synthesized PANI–DBSA and PANI–SDS latexes were characterized by IR and UV‐visible spectroscopies, and surface morphology was analyzed by transmission electron microscopy. The PANI–DBSA were found to be nanograin shaped whereas PANI–SDS were as nanofibers. In the second stage rheological properties of waterborne PANI latexes were characterized by viscosity measurement and their dispersion stability in water. The surface morphology of the coating was examined by scanning electron microscope (SEM). The anti‐corrosion performance of uncoated carbon steel, PANI–DBSA and PANI–SDS coated carbon steel was evaluated by tafel slope analysis and immersion test studies of 0.5, 1, and 1.5% PANI/Epoxy coatings were done in 5% NaCl aqueous solution. The results indicated that the nanoPANI in epoxy coating might work as an adhesion promoter and corrosion inhibitor. The waterborne latexes, thus, were found to be highly suitable and avoid the use of organic solvents or strong acids under environmentally benign conditions. Copyright © 2010 John Wiley & Sons, Ltd.