Sodium hypophosphite

About: Sodium hypophosphite is a research topic. Over the lifetime, 1695 publications have been published within this topic receiving 15932 citations.

Infrared spectroscopy studies of the effects of the catalyst on the ester cross-linking of cellulose by poly(carboxylic acids)

Abstract: The esterification of cellulose by a poly(carboxylic acid) proceeds in two steps: the formation of a 5-membered cyclic anhydride intermediate by the dehydration of two carboxyls, and the reaction between cellulose and the anhydride intermediate to form an ester. Sodium hypophosphite is the most effective catalyst for the esterification. The effect of sodium hypophosphite on the esterification of cotton cellulose was studied by Fourier transform infrared spectroscopy (FTIR). It was found that sodium hypophosphite accelerates both the formation of the cyclic anhydride intermediate and the reaction between the anhydride intermediate and cellulose. The chief role of sodium hypophosphite is possibly the acceleration of the esterification of cellulose by the anhydride intermediate. © 1993 John Wiley & Sons, Inc.

Co2P nanostructures constructed by nanorods: hydrothermal synthesis and applications in the removal of heavy metal ions

Abstract: In this paper, we report the successful synthesis of cobalt phosphide (Co2P) nanostructures built up of nanorodsvia a simple hydrothermal route using white phosphorus (WP), sodium hypophosphite and cobalt dichloride as starting reactants in the presence of polyvinylpyrrolidone (PVP, 30 K). The as-obtained product was characterized by means of X-ray powder diffraction (XRD), energy dispersive spectrometry (EDS), (high resolution) transmission electron microscopy (TEM/HRTEM), selected area electron diffraction (SAED) and field emission scanning electron microscopy (FESEM). It was found that sodium hypophosphite played an important role in the formation of the Co2P nanostructures. Some factors influencing the morphology of the product, including the reaction temperature, amount of sodium hypophosphite, surfactant, and so on, were investigated. The capacity of the product to remove heavy metal ions was also studied.

Combination of a hydroxy-functional organophosphorus oligomer and a multifunctional carboxylic acid as a flame retardant finishing system for cotton: part ii. formation of calcium salt during laundering

Abstract: Multifunctional carboxylic acids, such as 1,2,3,4-butanetetracarboxylic acid (BTCA), were used to bond a hydroxy-functional organophosphorus oligomer (FR) to cotton fabric in the presence of a catalyst, such as sodium hypophosphite (NaH2PO2). Previously, it was found that the cotton fabric treated with FR and BTCA showed a high level of phosphorus retention after one home laundering cycle. However, the flame retardant properties quickly deteriorated as the number of home laundering cycles was increased. In this research, it was found that the free carboxylic acid groups bound to the cotton fabric form an insoluble calcium salt during home laundering, thus diminishing the flame retardant properties of the treated cotton fabric. It was also found that the free carboxylic acid groups on the treated cotton fabric were esterified by triethanolamine (TEA), and that the formation of calcium salt on the fabric was suppressed by the esterification of the free carboxylic acid groups by TEA. The cotton fabric treated with BTCA and the hydroxy-functional organophosphorus oligomer significantly improved its flame retardance when a new catalyst system consisting of hypophosphorous acid (H3PO2) and TEA was used in the system.