Some biophysical properties of castor oil esterified with some acid anhydrides

✍ Scribed by Mona A. Saied; Samia H. Mansour; Mohamed Eweis; Maher Z. El-Sabee; Azima L. G. Saad; Kamal N. Abdel Nour

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 533 KB
• Volume: 110
• Category: Article
• ISSN: 1438-7697
• DOI: 10.1002/ejlt.200800001

✦ Synopsis

Abstract

A series of castor oil adducts were synthesized by esterification of castor oil with acid anhydrides: phthalic, maleic and succinic anhydrides. The chemical structure of castor oil and the prepared adducts were characterized by means of IR and ^1^H NMR spectroscopy. The number‐average and weight‐average molecular weights were measured by gel permeation chromatography. The electrical properties were studied through the permittivity, dielectric loss and conductivity measurements, which are considered to be in the range of electrical insulation. The electrical conductivity, which describes the ionic mobility of the systems, was found to be in the range of 10^–9^ to 10^–^^12^ S/cm. This indicates that castor oil and its esters could be used for antistatic applications. The viscosity η and the activation energy E~η~, obtained from the dependency of viscosity on temperature using the Arrhenius equation, were found to increase with increasing molecular weight of the system. The effect of different concentrations of castor oil and its esters on the growth activities of the sugar beet pathogens R. solani and S. rolfsii was studied through the determination of percent germination, average length of hyphal extensions, dry mass yield and the production of sclerotia. The obtained data indicate that the esterification of castor oil with anhydrides improves the antifungal activity.