Showing papers on "Sodium hypophosphite published in 2012"

Preparation of water-repellent cellulose fibers using a polycarboxylic acid/hydrophobic silica nanocomposite coating

Abstract: This research was carried out to embed hydrophobic silica nano-particles on the cotton surface using 1,2,3,4-butanetetracarboxylic acid (BTCA) as a crosslinking agent and sodium hypophosphite as a catalyst. The influence of the amount of silica nano-particles on the performance of the cotton fibers was investigated employing Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy (RS), Thermogravimetric analysis (TGA), limited oxygen index (LOI), scanning electron microscopy (SEM), water contact angle (WCA), reflectance spectroscopy (RS) and abrasion resistance (AR). The possible interactions between silica nano-particles, the crosslinking agent and the cotton functional groups at the surface were elucidated by ATR-FTIR and Raman spectroscopy. The results indicated that the embedded silica nano-particles modify the surface of fibers increasing the hydrophobicity and thermal stability of substrate. The microscopic analysis showed a uniform coating of silica nano-particles on the surface of fibers.

Sodium hypophosphite and nano TiO2 inorganic catalysts along with citric acid on textile producing multi-functional properties

Abstract: TGA curves of samples 1, 2, 5, 6 and control.► Using sodium hypophosphite/nano TiO 2 /citric acid producing textile with multi-functional properties. ► Applying friendly cross-linker to obtain durable properties on textile. ► Using available and cost effective materials in simple application to produce textile with diverse features. ► Introducing cotton/polyester knitted fabric with reasonable multi-functional properties.

Preparation of electromagnetic reflective wool using nano-ZrO2/citric acid as inorganic/organic hybrid coating

Abstract: Nano-ZrO 2 particles were stabilized on wool surface using citric acid (CA) as a crosslinking agent and sodium hypophosphite (SHP) as a catalyst under UV irradiation. The influence of the amount of nano-ZrO 2 on the performance of wool fiber was investigated by the use of Fourier transform infrared spectrophotometer (FTIR), horizontal flammability apparatus (HFA), scanning electron microscope (SEM), water contact angle tester (WCA), reflectance spectrophotometer (RS) and electromagnetic transition instrument (ETI). The possible interactions between nano-zirconia particles, cross-linking agent and wool free radicals were elucidated by the FTIR spectroscopy. Results indicated that the stabilized nano-zirconia enhances the flame retardancy and electromagnetic reflection of wool.

Biomedical Textiles Through Multifunctioalization of Cotton Fabrics Using Innovative Methoxypolyethylene Glycol- N -Chitosan Graft Copolymer

Abstract: Multifunctioalization of cotton fabrics was developed by a novel finishing formulation. The method is based on chitosan-N-polyethylene glycol graft copolymer along with citric acid and sodium hypophosphite (SHP) as catalysts. Treatment of the cotton fabric resulted in the chemical attachment of the copolymer to the cotton fabric via bridging-based esterification where the latter involves reaction of one molecule of the polycarboxylic acid (citric acid) with both the amino group of the copolymer and the hydroxyl groups of cotton. Inclusion of the copolymer in the crosslinked structure of cotton as well as by hydrogen bonding and van der Waals forces are additionally possible. Synthesis of the copolymer was raised out by the reaction of chitosan with methoxy polyethylene glycol (MPEG) aldehyde followed by the reduction with sodium borohydride. MPEG was prepared by oxidation of PEG with acetic anhydride in dimethyl sulphoxide at room temperature. Methoxypolyethylene glycol-N-chitosan graft copolymer (MPEG-N-CTS) structure was confirmed by IR, NMR, X-RD and TGA techniques. The copolymer is soluble in water. The pad dry-cure method was used for the cotton fabrics treatment with aqueous solution of prepared copolymer along with citric acid and SHP. The so treated fabrics were monitored for copolymer content (expressed as N%), crease recovery, tensile strength, elongation at break, air permeability, water permeability, roughness, bursting strength and antibacterial activity. Fabric performances based on the outputs of these measurements advocate these multifunctionalized fabrics for use as medical textile.

Enhancement of wrinkle recovery angle of cotton fabric using citric acid cross-linking agent with nano-TiO2 as a co-catalyst:

Abstract: In this research, the non-formaldehyde wrinkle-resistant treatment of cotton fabrics has been investigated using the citric acid (CA) as a cross-linking agent and sodium hypophosphite (SHP) as a catalyst together with nano-titanium dioxide (nano-TiO2) as a co-catalyst compound. The effect of the changes in the concentrations of CA, SHP, and nano-TiO2 on the wrinkle recovery angle (WRA), tensile strength, tearing strength, whiteness index, and flexural rigidity of cotton fabrics was studied using Box–Behnken design. It was found that the addition of nano-TiO2 could enhance the wrinkle resistance and decrease the flexural rigidity of the cotton fabric with little effect on the whiteness index, and tearing and tensile strengths of the treated fabric. The developed empirical models are found to be in good correlation with the selected variables (r2 ≥ 0.8). From this study, it was concluded that 10% CA, 10% sodium dihydrogen phosphate, and 0.1% nano-TiO2 were the optimum concentrations required to enhance the ...

Synthesis of highly stable dispersions of copper nanoparticles using sodium hypophosphite

Abstract: Highly stable dispersions of copper nanoparticles with an average diameter of 80 nm were synthesized using a straightforward and cost-effective method in the presence of polyvinylpyrrolidone (PVP) as a stabilizer and without any inert gas protection. Sodium hypophosphite was used as the reducing agent in low pH value aqueous medium. The copper nanoparticles were characterized by ultraviolet-visible spectroscopy and scanning electron microscopy. The mechanism of the PVP on the stabilization of copper nanoparticles is also discussed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

The Combination of Itaconic Acid and Sodium Hypophosphite as a New Cross-Linking System for Cotton

Abstract: In this research, we studied cross-linking of cotton fabrics using the combination of itaconic acid (ITA) and sodium hypophosphite (NaH2PO2). ITA, a bifunctional carboxylic acid, was able to esterify cotton cellulose to form a single ester linkage, but it was not able to form cross-linking between two cellulose molecules. In the presence of NaH2PO2, the amount of ester formed on cotton fabric was increased substantially and the esterification temperature of ITA was reduced. Therefore, NaH2PO2 functioned as a catalyst for esterification of cotton by ITA. Moreover, we found that wrinkle resistance of the cotton fabric was significantly improved when cotton fabrics were treated with the combination of ITA and NaH2PO2.We also found that phosphorus was bound to the treated cotton fabric and that the increase in the wrinkle recovery angle of the treated fabric was correlated to the increase in the amount of phosphorus bound to cotton. All the data indicated that H–P–H of sodium hypophosphite probably reacts wit...

Electroless nickel–phosphorus deposition on carbon steel CK-75 and study of the effects of some parameters on properties of the deposits

Abstract: Electroless nickel–phosphorus (Ni–P) deposition provides coatings with high hardness and excellent resistance to wear and abrasion. In this study, autocatalytic deposition of Ni–P alloy has been carried out on steel CK-75 sheets from bath containing nickel sulfate hexahydrate, sodium hypophosphite hydrate, thiourea, lactic acid, and sodium acetate. The effects of lactic acid concentration, pH and temperature on deposition rate, composition of deposits, and hardness have been studied. Also the changes in the hardness and structure of deposits by heat-treatment were studied by X-ray diffraction and scanning electron microscopy methods. It is shown that deposits crystallized after heat-treatment at 400°C for 1 h and crystallization to Ni and Ni3P was observed.

Influence of pH Solution on Electroless Copper Plating Using Sodium Hypophosphite as Reducing Agent

Abstract: The effect of pH solution on the electroless deposition of copper-rich Cu–Ni–P alloys, using hypophosphite as reducing agent, has been carried out. The deposition rate increased obviously with the increase of pH. The surfaces morphology, the roughness and the cristallinity depend many of pH. The kinetics of copper electroless was investigated by means of cyclic voltammetry and electrochemical impedance spectroscopy. The shape of voltammogramms and impedance diagram depend also of the pH solution.

Magnesium alloy direct chemical plating NI-P-SiC plating solution formula and plating process

Abstract: The invention provides a magnesium alloy direct chemical plating NI-P-SiC plating solution formula and a plating process. The formula consists of chemical plating Ni-P plating solution and SiC dispersing solution, wherein the chemical plating Ni-P plating solution comprises 20-30g/l of nickel sulfate, 20-30g/l of sodium hypophosphite, 15-30g/l of complexing agent, 15-25g/l of sodium acefate, 10-20g/l of fluoride, 1-2mg/l of stablizer, appropriate amount of pH value modifier and the balance of water; the SiC dispersing solution is formed by stirring 10-80mg/l of surface active agent and 1-8g/lof micron SiC by magnetic force; and after pretreatment of the magnesium alloy, a Ni-P-SiC composite plating layer with thickness being 20-50Mum is obtained under the process conditions that the temperature is 80-90 DEG C, the pH value is 4.8-5.6, and the plating time is 60-120 minutes. In the invention, basic nickel carbonate is replaced by nickel sulfate which is introduced as main salt; and the micron SiC is added to conduct plating directly; on the base of keeping the excellent performance of magnesium alloy chemical plating Ni-P alloy, the rigidity and abrasive resistance of the magnesium alloy chemical plating layer are greatly improved; the problem of lower abrasive resistance of magnesium alloy nickel-plating layer is solved; and the preparation of the plating solution is convenient, the cost is low, the plating solution is stable and the deposition rate is quick.

Nano-TiO2/maleic acid/triethanol amine/sodium hypophosphite colloid on cotton to produce cross-linking and self-cleaning properties

Abstract: Application of a colloid of nano-titanium dioxide (nano-TiO2), maleic acid (MA), sodium hypophosphite (SHP), and triethanol amine on cotton fabrics through pad–dry–cure process was investigated to produce a cross-link cotton fabric with self-cleaning properties without yellowing. The central composite design was used for variables based on Design of Expert software. The degradation of methylene blue on the surfaces of treated fabrics was monitored to investigate the self-cleaning property. Also the crease recovery angles (CRA) of the fabrics was studied to investigate cross-linking of cotton fabric. Moreover, the surfaces of the treated cotton fabrics were observed by scanning electron microscopy (SEM). The optimum treatment conditions to obtain cross-linking and self-cleaning properties on the cotton fabric were introduced. Increasing concentrations of MA to 20% increased the fabric CRA due to cross-linking of cellulose in the presence of MA and SHP. The treated fabrics have good self-cleaning performanc...

Introducing covalent and ionic cross-linking into cotton through polycarboxylic acids and nano TiO2

Abstract: In this study, cationized cotton (CC) fabrics were treated with polycarboxylic acids and nano titanium dioxide (NTO) to produce fabrics with enhanced cross-linking property. The CC cross-linking with butane tetra carboxylic acid and citric acid in the presence of sodium hypophosphite catalyst and NTO co-catalyst under different curing methods were optimized using a statistical approach. The central composite design was used for variables based on Design of Expert software. The appropriate models to create optimum dry crease recovery angle were obtained for each condition. The results show that the covalent and ionic linkages lead to the cross-linking improvement of CC. X-ray diffraction and scanning electron microscopy were also applied to indicate the NTO particles on the cotton surface with the size of nano particles and their crystallinity.

Influence of deposition parameters and kinetics of electroless Ni-P plating on polyester fiber

Abstract: The electroless nickel-phosphorous (Ni-P) plating on polyester fiber using sodium hypophosphite as a reducing agent in alkaline medium was studied The effects of plating parameters including concentrations, pH and bath temperature of the plating bath on deposition rate of the electroless Ni-P plating were investigated The results reveal that the deposition rates increase with the increase in the concentration of nickel sulfate, sodium hypophosphite, pH and bath temperature, respectively However, it is determined that the deposition rates decrease with the rise of sodium citrate The kinetics of the deposition reaction was investigated and an empirical rate equation for electroless Ni-P plating on polyester fiber was developed

Method for synthesizing dialkyl hypophosphorous acid

Abstract: The invention discloses a method for synthesizing a dialkyl phosphinic acid and belongs to the technical field of organic phosphorous compound preparation. The method comprises: mixing sodium hypophosphite and an alpha-alkene according to ratio and pouring the mixture in a closed reaction kettle which has a stirrer and can be heated, wherein the optimal alpha-alkene to sodium hypophosphite molar ratio is 2.2 to 2.7; mixing a low/or medium-temperature radical initiator and a high-temperature radical initiator according to a ratio of 5-0.1:1 and pouring the mixture into a reaction kettle; closing the reaction kettle and stirring the mixture for reaction for 2 to 40 hours at 40 to 200 DEG C; cooling the mixture, opening the reaction kettle, filtering the mixture and transferring a filtrate into a separating funnel and washing the filtrate; and evaporating an obtained organic phrase in a rotary mode to remove unreacted materials and solvents. A product obtained after the steps is the dialkyl phosphinic acid. The dialkyl phosphinic acid can provide a high-efficiency flotation agent or extracting agent used in the fields of ore flotation and metal iron extraction and separation. The method improves reaction rates, simplifies a post treatment process, reduces production costs and improves product purity.

Polyacrylic acid or copolymer thereof and preparation method of polyacrylate or copolymer salt thereof

Abstract: The invention relates to a preparation method of an organic polymer and in particular discloses a preparation method of polyacrylic acid or a copolymer thereof. The method comprises the following steps: firstly preparing 3-62% of acrylic acid or methacrylic acid, 0-48% of comonomers, 0.05-35% of sodium hypophosphite and 30-96% of water; mixing the prepared raw materials all together and stirring the mixture uniformly, placing the mixture in a 60Co gamma ray radiation field to undergo radiation-induced polymerization, with radiation dose of 1.2-30KGy and obtaining the polyacrylic acid or the copolymer thereof after polymerization; and neutralizing the prepared polyacrylic acid or the copolymer thereof in aqueous alkali until the pH value is 6.5-9, thus obtaining polyacrylate or copolymer salt thereof. The invention has the following advantages: the energy consumption is low, the equipment utilization ratio is high, the process is simple and the operation is convenient, chemical initiators are avoided, the product performance is excellent, the production safety and environment-friendliness are better and the product can serve as a dispersing agent, a scale inhibitor, a thickening agent, a flocculating agent, etc.

Electroplating pretreatment method for acrylonitrile butadiene styrene (ABS) plastic surface

Abstract: The invention relates to an electroplating pretreatment method for an acrylonitrile butadiene styrene (ABS) plastic surface The electroplating pretreatment method comprises the following process steps of: eliminating stress, performing alkali washing for oil removal, pickling, roughening, performing neutralizing treatment, performing chemical activation, and performing the conventional electroplating, wherein in the chemical activation process, plastic base materials are put in to an activation solution and are subjected to hyperthermic treatment in a water bath for a certain period of time, each liter of the activation solution comprises 10 to 12g of nickel sulfate, 20 to 25g of sodium hypophosphite and 5 to 8g of sodium citrate, the pH is 9 to 11, and the temperature is between 70 and 75 DEG C In the invention, a novel method in which metal palladium activation is not used is provided, can be used for replacing a sodium borohydride and methanol activation process and contributes to environment friendliness; and on the basis of pretreatment, the plastic surface can be directly electroplated, so that the problems of complicated treating processes, high PdCl2 prices, high pollution possibility of a plating solution and the like are solved

Method for preparing aluminum hypophosphite

Abstract: The invention relates to a method for preparing aluminum hypophosphite. The method includes the following steps of firstly, preparing sodium hypophosphite solution with concentration of 2-6mol/L, adjusting pH (potential of hydrogen) to be 3-5 preferentially within 3-6.5; secondly, preparing aluminum sulfate solution; and thirdly, subjecting the sodium hypophosphite solution and the aluminum sulfate solution to reaction by heating on the acid condition to generate aluminum hypophosphite. The aluminum sulfate is added into the sodium hypophosphite solution for reaction within a certain temperature range, so that harms caused by volatilization of hypophosphorous acid during preparing of the aluminum hypophosphite are avoided, operation is simplified, yield of products is high, cost is low and industrialization is easy to realize.

Animal hair solvent and preparation method and use of keratin solution

Abstract: The invention discloses an animal hair solvent and the preparation method and use of keratin solution. The solvent is characterized in that tris(2-carboxyethyl)phosphine hydrochloride, tris(2-cyanoethyl)phosphine or trisphosphine is used as a main ingredient and is mixed with 1 to 8 percent of assistant which may be at least one of mercaptoacetic acid, mercaptoethanol, sodium hydrogensulfite, potassium bisulfate, sodium sulfite, potassium sulfite, sodium hypophosphite, ethanol, methanol and urea. The preparation method adopts the following processes: 1, preparing animal hair solution by usingthe animal hair solvent of the invention; 2, dissolving animal hair in the solution to prepare keratin solution; and 3, adding a proper amount of acid to perform the post-treatment of the keratin solution. The use is to use the keratin solution as textile finishing liquor or the main functional ingredient of the textile finishing liquor.

Process for production of nanoparticles of solid lubricant and lubricant dispersions stable in oil and in water

Abstract: The process basically comprises: dissolving a lamellar disulphide, as a source of the solid lubricant, in an aqueous solvent, forming a first aqueous solution; dissolving a reducing agent, as hydroxylamine, sodium hypophosphite or sodium borohydride, in an aqueous solvent, forming a second aqueous solution; mixing the first and second aqueous solutions, forming a third aqueous solution; neutralizing the pH of the third aqueous solution; dissolving a sulphur source, in an aqueous solvent, forming a fourth aqueous solution; mixing the third and fourth aqueous solutions, forming a fifth aqueous solution, which is contained and heated in an autoclave; cooling the fifth aqueous solution to the room temperature; and removing, from the autoclave, the nanoparticles in powder form.

Corrosion resistance of decorative chromium films obtained from trivalent chromium solutions

Abstract: In this work, the resistance to corrosion of chromium films obtained from trivalent chromium solutions of different compositions and the influence of solution compounds on the coatings electrochemical behavior and the microstructure were studied. The chromium coatings were obtained from trivalent solutions in a chloride-based bath with different complexing agents adding also sodium hypophosphite and aluminum chloride. UV-vis spectroscopy was carried out on all solutions before and after plating to observe changes in the chromium complexes chemical state due to the plating process. Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) were performed to examine the coatings surface morphology and composition; respectively. The coulometric method was used for measuring coating thickness. Electrochemical impedance spectroscopy (EIS) was done using 3% NaCl as electrolyte and using a three-electrode cell with a standard calomel electrode (SCE) as reference. Bright chromium films were obtained from all baths however, differences were observed concerning morphology, thickness and corrosion resistance depending on the composition of the forming solution.

New electroless copper plating bath using sodium hypophosphite as reductant

Abstract: In this paper, a new environment friendly electroless plating bath using sodium hypophosphite as reductant and nitrilotriacetic acid as complexing agent was investigated under the acid condition The effects of bath temperature, pH, CuSO45H2O concentration, nitrilotriacetic acid concentration and NaH2PO2H2O concentration upon the deposition rate and the bath stability were studied The electrochemical results indicated that the deposition rate of the electroless copper increased with the decrease in the pH, and it reached 2·4 μm h−1 when the bath pH was 6·0 The as deposited Cu films were characterised by energy dispersive X-ray analyser, X-ray diffraction, atomic force microscopy and resistivity measurement The quality of the Cu films were improved by the addition of a surfactant PEG-600, and a uniform copper film with a low resistivity (2·60 μΩ cm) was obtained, which was able to be used as seed layer for electroplating Cu

Method for measuring sulfate radical in sodium hypophosphite

Abstract: The invention provides a method for measuring a sulfate radical in sodium hypophosphite. The method is characterized by comprising the following steps: placing a sodium hypophosphite sample in a color comparison tube; dissolving the sample with water; adding a stabilizing agent; sequentially adding a hydrochloric acid solution and a BaCl2 solution; diluting with distilled water to reach the set scale, shaking uniformly, and keeping standing; measuring the absorbance at 460nm by a 3cm cuvette instantly; and calculating the content of the sulfate radical in the sample according to the relation between the sulfuric acid concentration and the absorbance. In the method for measuring the sulfate radical in the sodium hypophosphite, glycerol which has excellent stabilization is utilized as the stabilizing agent. By the method, the ppm level sulfate radical contained in the sodium hypophosphite can be stably and accurately measured quantitatively.

Pulse-electrodeposited Ni-Co-P/HBN composite plating and preparation method thereof

Abstract: A pulse-electrodeposited Ni-Co-P/HBN composite plating and a preparation method thereof. The preparation method adopts a metal material as a substrate, and comprises the following steps: firstly pretreating the substrate surface, preparing a composite plating solution with nickel sulfate, cobalt chloride, sodium hypophosphite, citric acid, trisodium citrate, boric acid, and polyvinyl alcohol as main components and hexagonal boron nitride HBN powder as a dispersed phase, performing surface modification and dispersion treatment of the HBN particles by using a surfactant through ultrasonic vibration, allowing the HBN particles to disperse uniformly in the plating solution through reasonable setting of pulse electrodeposition parameters and full stirring, performing codeposition and heat treatment of the HBN particles and the substrate metal nickel cobalt phosphor in a state of applying pulsed current so as to obtain a corrosion-resistant, wear-resistant and antifriction pulse-electrodeposited Ni-Co-P/HBN composite plating. The invention overcomes defects of single component of current composite plating, coarse plating crystal grain, low interface bonding strength with the substrate, non-ideal comprehensive properties of corrosion resistance, wear resistance, and antifriction, and the like; the pulse-electrodeposited Ni-Co-P/HBN composite plating of the invention is applicable to wear-resistant, antifriction and corrosion-resistant surface plating of friction kinematic pair parts in industries of machinery, metallurgy, chemical engineering, and the like.

Quadripolymer-type corrosion-inhibition scale inhibitor PMAHS and preparation method thereof

Abstract: The invention discloses a quadripolymer-type corrosion-inhibition scale inhibitor PMAHS. The quadripolymer-type corrosion-inhibition scale inhibitor PMAHS comprises maleic anhydride (MA), acrylic acid (AA), hydroxyethyl acrylate (HEA), sodium methallylsulfonate (SMAS), sodium persulfate, sodium hypophosphite, isopropanol and water. The invention also discloses a preparation method of the quadripolymer-type corrosion-inhibition scale inhibitor PMAHS. The quadripolymer-type corrosion-inhibition scale inhibitor PMAHS has excellent effects of inhibiting production of calcium phosphate scales and calcium carbonate scales and especially phosphate scales, has good iron oxide dispersibility, has functions of corrosion inhibition, high temperature resistance and acid and base resistance, and has a stable molecular structure and low phosphorus content. The preparation method does not produce three wastes in production. The quadripolymer-type corrosion-inhibition scale inhibitor PMAHS has the advantages of simple circulating cooling water treatment processes, low use amount, low cost, good effects, good economic benefits and wide social benefits.