Sodium hypophosphite

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

Production of nanometer silver powder by liquid-phase and solid-liquid separating method

Abstract: A solid-liquid separation method for preparing Ag nanoparticles by liquid phase process includes such steps as preparing nano-class Ag sol by liquid-phase reduction method of sodium hypophosphite, adding regulator in ultrasonic field, laying aside for several hours, and separating Ag nanoparticles by gravitational deposition or vacuum filtering.

Stiffening agent for cotton woven fabrics made from methacrylic acid vinyl acetate methylacrylate terpolymer

Abstract: The emulsion polymerizations of methacrylic acid (MAA), vinyl acetate (VAc), and methyl acrylate (MA) in different VAc/MA molar concentrations (X1, 0.232/0.813; X2, 0.348/0.697; X3, 0.456/0.581; X4, 0.581/0.465; X5, 0.697/0.348) and fixed MAA concentration (0.116 mol) were carried out using sodium dodecyl sulfate (SDS; 34 mmol) as emulsifier and potassium persulphate (K2S2O8; 37 mmol) as initiator at 70 °C for 6 h in semicontinuous reaction mode. The average molecular weights (Mn, Mw) and the molecular weights distributions were determined using gel permeation chromatography (GPC). All terpolymers prepared showed monomodal molecular weights distributions. Glass transition (Tg), crystallization (Tc), and melting (Tm) temperatures and thermal stability of the prepared terpolymers were determined using differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA), respectively. The elongation percentage at rupture, tensile strength and accelerated thermal aging were determined for X1–5 terpolymers, as functions of the molar composition in the emulsion polymerization feed. The terpolymers prepared, X1–5 terpolymers, were tested as stiffening agents for cotton woven fabrics through crosslinking to cellulose, using sodium hypophosphite monohydrate (NaH2PO2·H2O) as catalyst. The effect of X1–5 compositions upon the stiffening efficiency was discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 2006

Electroless composite plating treatment of metallic material

Abstract: PURPOSE: To provide the treatment by which a mold material can freely be selected from metallic materials having excellent workability and the durability of a mold after forming can be secured through performing the treatment for enhancing durability of the mold based on physical and chemical considerations and accordingly, the working period for forming the mold can also be shortened. CONSTITUTION: In this treatment, a metallic material to be heated is placed in a dual electroless plating tank and at the same time, an electroless composite plating bath is supplied to the plating tank. At this time, desirably, the plating tank is heated with steam so that the treating temp. becomes equal to 92 deg.C of the plating bath temp. and also the plating bath is supplied while stirring it. As the electroless composite plating bath, a bath obtained by using an Ni-P electroless plating bath as its base and adding ceramics or the like to this Ni-P electroless plating bath is employed to subject the metallic material to composite plating treatment with e.g. Ni-P-SiC. In this experiment, sodium hypophosphite (NaH2 PO2 .H2 O) is used as a component of the electroless composite plating bath.

Preparation method of composite cyclodextrin hydrogel

Abstract: The invention discloses a preparation method of composite cyclodextrin hydrogel. The preparation method comprises the following steps that 1, sodium hypophosphite is used as a catalyst, and beta-cyclodextrin and citric acid are subjected to a grafting reaction; 2, a grafting product of the beta-cyclodextrin and the citric acid is grafted to nano-microcrystalline cellulose by using the sodium hypophosphite as the catalyst; 3, ppo segment and chain of triblock copolymer pluronic enters a cavity of the product in the step (2) through ultrasonic treatment; 4, alpha-cyclodextrin is added, and standing is performed for hydrogel forming. The prepared hydrogel has the unique structure and good biocompatibility, the gelation time is short, the gelation strength is higher than that of common gel, and hydrogel can be formed at room temperature; the application prospect is wide in the aspects of functional materials, biological medicine carrying and the like.

Deposition of high wear resistance of Ni‐composite coatings

Abstract: Electrodeposited Ni‐P composite coatings incorporating a variety of inorganic particles were obtained from Watt’s nickel bath containing sodium hypophosphite. The mechanism of co‐deposition of various particles (SiC, Al2O3, quartz and sand) was studied in view of the electro‐kinetic charge characterizing the solid particles. Means to improve the mobility of the particles in the plating solution were investigated using sodium oleate as surface active agent. The purpose was to increase particle content in the coating to attain high hardness values. Special attention was given to the deposition process using SiC particles. The surface morphology, hardness and wear resistance of the composite coatings were determined. Hardness values were maximized by simple heat treatment in air atmosphere which led to the precipitation of the hard Ni3P phase. Sound, coherent and high wear resistance coatings could be produced.