Sodium hypophosphite

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

An Experimental Approach for Optimizing Coating Parameters of Electroless Ni-P-Cu Coating Using Artificial Bee Colony Algorithm.

Abstract: This paper aims to present an experimental investigation for optimum tribological behavior (wear depth and coefficient of friction) of electroless Ni-P-Cu coatings based on four process parameters using artificial bee colony algorithm. Experiments are carried out by utilizing the combination of three coating process parameters, namely, nickel sulphate, sodium hypophosphite, and copper sulphate, and the fourth parameter is postdeposition heat treatment temperature. The design of experiment is based on the Taguchi L27 experimental design. After coating, measurement of wear and coefficient of friction of each heat-treated sample is done using a multitribotester apparatus with block-on-roller arrangement. Both friction and wear are found to increase with increase of source of nickel concentration and decrease with increase of source of copper concentration. Artificial bee colony algorithm is successfully employed to optimize the multiresponse objective function for both wear depth and coefficient of friction. It is found that, within the operating range, a lower value of nickel concentration, medium value of hypophosphite concentration, higher value of copper concentration, and higher value of heat treatment temperature are suitable for having minimum wear and coefficient of friction. The surface morphology, phase transformation behavior, and composition of coatings are also studied with the help of scanning electron microscopy, X-ray diffraction analysis, and energy dispersed X-ray analysis, respectively.

Magnesium alloy surface chemical nickel plating solution and method thereof

Abstract: The invention relates to a magnesium alloy chemical nickel plating solution. Every liter of the solution contains 30-35g of nickel sulfate, 25-30g of complexing agent sodium citrate, 30-35g of reducer sodium hypophosphite, 0.001-0.003g of stabilizer glycine, 30-35g of buffering agent sodium lactate, 0.005-0.01g of wetting agent OP-10 and the balance deionized water. The method comprises the following steps: polishing the surface of a magnesium alloy part, sanding, degreasing, dipping the magnesium alloy part into the chemical nickel plating solution of which the temperature is 80-90 DEG C and the pH value is 5-6, and applying a potential of -0.5 - -0.7V to carrying out anodic polarization for 30-120 seconds, wherein the magnesium alloy part to be plated is used as a working electrode, a corrosion resistant plate is used as an anticathode, and a saturated calomel electrode is used as a reference electrode; and after removing the external voltage, directly carrying out chemical plating in the nickel plating solution for 15-25 minutes, taking out the magnesium alloy part, washing with deionized water, rinsing and drying in the air. The invention is easy to operate, and has the advantages of low cost and less pollution; and the obtained chemical plating layer is uniform, and has the advantages of strong impact resistance, high corrosion resistance and good metallic appearance.

Alternative microwave curing approach for imparting ease and care characteristics and antimicrobial activity to viscose fabric

Abstract: This study aims to use multi-functional viscose fabric that was facilely developed with with respect to ease and care characteristics, reinforcement effect and antibacterial activity by using novel echo friendly antibacterial finish based on citric acid/sodium hypophosphite and the authors’ previously tailor-made poly meth acrylic acid (MAA)-chitosan graft copolymer via alternative microwave curing approach instead of traditional high-temperature cure one.,Viscose fabric was paddled twice in the cross-linking formulations containing different concentrations of citric acid, poly (MAA)-chitosan graft copolymer and sodium hypophosphite to 90 % wet pick up and dried at 100°C for 3 min in an electric oven. Then, the treated fabrics were placed on the disk spinner of the microwave oven and cured at different power (100–800 Watt) for various durations (60–180 s). The fabric was then water-rinsed and dried at ambient condition before use.,Results revealed that the above echo friendly method for finished viscose fabrics was found to achieve relatively high dry wrinkle recovery angle and maintain the loss in tensile strength within the acceptable range, as well as antibacterial activity against Escherichia coli and Staphylococcus aureus as a gram-negative and gram-positive bacteria, respectively; in addition to durability up to ten washing cycles. Furthermore, scanning electron microscope images, nitrogen content and add on % of the finished fabric confirmed the penetration of grafted chitosan inside the fabric structure. The tentative mechanism for these reactions is advocated.,The novelty addressed here is undertaken with the advantages of using citric acid as a nonformaldehyde, safe and cheap poly carboxylic acid as a crosslinking agent and sodium hypophosphite as a potential catalyst, in addition to the authors’ noncitable multifunctional echo friendly tailor-made poly (MAA)-chitosan graft copolymer for imparting reinforcement and antibacterial characteristics to viscose fabric that uses the pad-dry/cure microwave fixation for progressively persuaded heat within the fabric during curing.,This was done to see the impact of microwave as green and efficient tool with respect to reduction in organic solvents, chemicals and exposer time as well as fixation temperature on the finishing reaction in comparison with traditional pad-dry-cure method.,Poly (MAA)-chitosan graft copolymer as amphoteric biopolymer was expected to impart multifunctional properties to viscose fabrics especially with comparable dry wrinkle recovery angle and minimize the loss in tensile strength in addition to antibacterial properties in comparison with untreated one.

Grinding-aid dispersant of inorganic powder body of aqueous acrylic phosphinates and preparation method thereof

Abstract: The invention discloses a grinding-aid dispersant of inorganic powder body of aqueous acrylic phosphinates and a preparation method thereof. The grinding-aid dispersant comprises the following raw materials in percentage by weight: 1-6% of sodium hypophosphite, 9-34% of acrylic monomers, 0.5-5% of free radical initiators and 60-80% of water. The preparation method comprises the following steps: stirring aqueous solution of the sodium hypophosphite and raising the temperature to 40-70 DEG C; adding the acrylic monomer solution with concentration of 25-75% in percentage by weight and the free radical initiator aqueous solution with concentration of 1-8% in percentage by weight and keeping uniform charging speed, then raising the temperature to 85-90 DEG C and reacting for 0.5-4 hours; and regulating the pH value of the obtained product to be 6-8 with sodium hydroxide solution and discharging the product after cooling the product to room temperature. The grinding-aid dispersant is applied to improving the grinding efficiency in grinding production of inorganic materials and simultaneously improving the mobility and dispersibility of the powder body.