The Preparation of Chlorinated Rubbers from Latex. Hypochlorination and Chlorination Processes

1934 ◽  
Vol 7 (2) ◽  
pp. 320-326 ◽  
Author(s):  
G. F. Bloomfield ◽  
E. H. Farmer
Keyword(s):  
Limited Range ◽  
Rubber Latex ◽  
Chemical Reagent ◽  
Direct Introduction ◽  
Chemical Reagents ◽  
Ph Values

Abstract With the view of extending the field of application of rubber latex, it has been considered desirable to study the behavior of this material toward various chemical reagents. Owing to the colloidal nature of latex the choice of reagent is considerably restricted; acids and many salts (especially those of bivalent and tervalent metals) produce coagulation, while alkaline reagents may cause creaming and aggregation of the particles. It is known that with the aid of certain stabilizers (e. g., saponin or casein) a stable acid latex may be obtained, but this is in general only stable over a limited range of pH values and is not stable to heat; moreover the stabilizer itself is prone to attack by the chemical reagent introduced. As would be anticipated from the foregoing considerations, the direct introduction of chlorine into latex immediately causes coagulation. Ellis and Boehmer (U. S. Patent 1,544,535) appear to have achieved some measure of success in chlorinating latex by using liquid chlorine under pressure, but the products obtained in different operations varied considerably in their properties.

Development of Retrieve/Storage Cabinets for Chemical Reagents

2014 ◽  
Vol 577 ◽  
pp. 457-460
Author(s):  
Hang Wei Zhang ◽  
Jian Feng Huang
Keyword(s):  
Management Information System ◽  
Storage Device ◽  
Application Software ◽  
Single Chip ◽  
Mechatronic System ◽  
Management Information ◽  
Single Chip Microcomputer ◽  
Chemical Reagent ◽  
Chemical Reagents ◽  
The Internet Of Things

To integrate chemical reagent retrieve/storage (R/S) device with management information system, an intelligent mechatronic system is developed. Three kinds of unit cabinets for reagent bottles are constructed. A Single-chip Microcomputer and a Personal Computer are served as a slave and host control system respectively. A set of special application software is programmed by VC++ and Access to accomplish reagent retrieve/storage, usage reports and surplus warning by short massage based on the Internet of Things. The integration of chemical reagent R/S device with MIS is realized which could make the storage device automation, data visualization and measurement precision.

Physico-chemical models of galena flotation system

2014 ◽  
Vol 11 (5) ◽  
pp. 447-456
Author(s):  
M. Chettibi ◽  
A. Abramov ◽  
A. Boutrid
Keyword(s):  
Main Idea ◽  
Oxidation Products ◽  
Lead Sulphide ◽  
Flotation Process ◽  
Chemical Reagents ◽  
Ph Values ◽  
Chemical Models ◽  
Sorption Layer ◽  
Physico Chemical ◽  
Automation Systems

Main idea to prevent the ground contamination by heavy metals is to extract them maximally with minimum consumption of chemical reagents. So, a perfect studying of pulp ionic structure, an adjustment of the sulphuric ores flotation parameters and modelling of minerals selectivity variables, by using the thermodynamic method of analysis, the behavior of lead xanthenes surface state in solution and experimental investigation results, allow obtaining quantitative physico-chemical models of minimum necessary xanthenes concentration of lead sulphide complete flotation.The optimal pH values, ensuring a complete flotation of galena agree with the potential of zero or minimum charge of its surface, and the optimal composition of the collector sorption layer consisting both of chemisorbed xanthenes and physically adsorbed dixanthenes.In additional, it was obtained quantitative models for the necessary xanthenes concentration of lead sulphide complete flotation in the case of different oxidation products from the galena surface in pH values from 7,0 up to 12,0.The models derived can be used as the criteria for functional units of automation systems to control and regulate the flotation process in mineral processing plants. All these should conduct to increasing of metals extraction degree with minimum chemical reagents consumption and providing good environmental protection.

Study on Intermolecular Forces of Corn Gluten with the Chemical Reagent Treatment

2014 ◽  
Vol 1049-1050 ◽  
pp. 547-550
Author(s):  
Rong Yan ◽  
Xin Hua Li ◽  
Xiao Jun Qi
Keyword(s):  
Microscopic Observation ◽  
Starch Granule ◽  
Intermolecular Forces ◽  
Small Granule ◽  
Intermolecular Hydrogen Bonds ◽  
Chemical Reagent ◽  
Chemical Reagents ◽  
Corn Gluten ◽  
Reagent Treatment ◽  
Observation Results

Corn gluten were steeped with different chemical reagents, 2%urea, 5%tween80, 5% NaCl, 2%L - cysteine, using distilled water as control. Intermolecular forces in corn gluten under different reagents were analyzed using the amount of free starch measuring by iodine calorimetry. By the light microscope, intermolecular structure transformation in corn gluten was analyzed before the treatment and after. The results show that Urea, twain, NaCl, and L-cysteine all can make the starch that closely combined with protein migrate away, in which the effect of L-cysteine and NaCl were better, releasing more free starch. It is found through microscopic observation that the starch granule existing in corn gluten is small granule from cutin endosperm, and microscopic observation results consistent with the free starch results. By analysis of the amount of free starch and the microscopic structure change of corn gluten and the mechanism of measuring intermolecular forces with the chemical reagent, it is demonstrated that disulfide bond and electrostatic attraction were main intermolecular forces in corn gluten, which was the main reason for the search combining with the protein .The effect of intermolecular hydrogen bonds and hydrophobic interaction were weaker.

scholarly journals Quality Analysis of Selected Toilet Soaps in Saudi Arabia Markets

2020 ◽  
pp. 7-14
Author(s):  
E. E. Shehata
Keyword(s):  
Saudi Arabia ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Limited Range ◽  
Quality Analysis ◽  
Fatty Matter ◽  
Caustic Alkali ◽  
Ph Values ◽  
Free Caustic Alkali ◽  
Total Fatty Matter

Soap is sodium or potassium salt of fatty acid produced by saponification reaction. The physicochemical properties of soaps determine their quality and hence determine their efficiency. Four toilet soaps from local markets in Saudi Arabia were analyzed for moisture, pH, free caustic alkali or free fatty acid, total fatty matter and insoluble matter in alcohol. The percentage of the moisture ranged between (3.0534±0.1782 -5.1235±0.4891 %), total fatty matter (79.6907± 0.0534 - 94.8253 ± 0.0622), insoluble matter in alcohol (0.7939± 0.0134 - 1.0368± 0.0234% (and there is no excess free caustic alkali. However, the pH values between (8.715±0.0219 - 9.745±0.0212). This study showed that the percent of moisture, free caustic alkali, insoluble matter, total fatty matter and pH values for different samples found to be in limited range. Finally, the percentage of free fatty acid are (1.0433±0.0813 -1.4107±0.1731%). The soaps analyzed proved to be of high quality and meet the standard values.

Electrochemical Aspects of Rubber Latex, Compounding Ingredients, and Their Mixtures

1957 ◽  
Vol 30 (1) ◽  
pp. 250-253
Author(s):  
Brojeswar Roy
Keyword(s):  
Zinc Oxide ◽  
Isoelectric Point ◽  
Rubber Latex ◽  
Lower Range ◽  
Latex Particles ◽  
Ζ Potential ◽  
Ph Values ◽  
China Clay ◽  
Kunitz Type ◽  
Latex Compounding

Abstract The electrophoretic speeds of rubber latex particles as well as of colloidally dispersed compounding agents, e.g., zinc oxide, sulfur, china clay, and mixtures of them as are generally employed in baths for electrodeposition, have been measured in a microcataphoresis cell of the Northrup-Kunitz type. The ζ-potential of latex, calculated from the electrophoretic speeds, is considerably influenced by the presence of the compounding agents. Sulfur sol having the lowest ζ-potential tends to reduce that of latex as well as of others in a mixture, whereas zinc oxide and china clay, which have higher ζ potentials, tend to increase the value for latex. A mixture of zinc oxide and china clay shows the highest (60 mV) ζ-potential compared to latex itself (ζ=28.8mV). The isoelectric point of rubber latex was measured by calculating the ζ-potential from the electrophoretic speed at different pH values, which were maintained by means of Na2CO3⋅NaHCO3 buffers at the higher range and acetate buffers at the lower range. The I.P. was 4.2 and was lowered in the presence of zinc oxide and china clay sols to 3.0 and 3.8, respectively, but increased to 5.1 in the presence of sulfur sol.

scholarly journals A Laboratory Manual for the Preparation of Chemical Reagents, Solutions and Special Indicators

2021 ◽  
Vol 1 (12) ◽  
pp. 1-62
Author(s):  
Yiglet Mebrat
Keyword(s):  
Chemical Solution ◽  
Laboratory Safety ◽  
Microbial Biodiversity ◽  
Chemical Reagent ◽  
Laboratory Manual ◽  
Staining Solution ◽  
Chemical Reagents ◽  
Solution Preparation

A Laboratory Manual for the Preparation of Chemical Reagents, Solutions and Special Indicators. ETHIOPIAN BIODIVERSITY INSTITUTE, Microbial Biodiversity Directorate. This manual includes detailed view of the following: Laboratory Safety Precautions, Chemical Reagent Preparation, Buffer and Chemical Solution Preparation, Staining Solution Preparation, Indicators and Dye Solution Preparation, Preparation of Special Reagents, Known and Suspected List of Carcinogens and References.

Interaction Between Ceria and Hydroxylamine

2003 ◽  
Vol 767 ◽  
Author(s):  
Subramanian Tamilmani ◽  
Jilei Shan ◽  
Wayne Huang ◽  
Srini Raghavan ◽  
Robert Small ◽  
...  
Keyword(s):  
Kinetic Study ◽  
Chemical Mechanical Polishing ◽  
Redox Reactions ◽  
Silicon Oxide ◽  
Oxide Films ◽  
Oxide Surfaces ◽  
Chemical Reagents ◽  
Ph Values ◽  
Kinetics Of Dissolution ◽  
Kinetics Of

AbstractCeria containing slurries are increasingly used in the chemical mechanical polishing of CVD silicon oxide films to obtain STI structures. Unlike silica or alumina, ceria has redox characteristics. Because of this characteristic, removal of ceria particles from planarized surfaces may be possible using chemical reagents that can participate in redox reactions. One such reagent is hydroxylamine, which is already being used in copper CMP. The objective of the work reported in this paper was to characterize the reaction between ceria and hydroxylamine, especially with respect to dissolution of ceria particles. A kinetic study of the dissolution of ceria in hydroxylamine solutions maintained at various pH values has been performed. The extent and kinetics of dissolution of ceria has been determined by ICPMS. Removal of ceria particles from oxide surfaces using hydroxylamine-based chemistries has been investigated.

scholarly journals Biocementation Potential of Tropical Residue Soil Infused with Facultative Anaerobe Bacteria

2015 ◽  
Vol 773-774 ◽  
pp. 1412-1416 ◽  
Author(s):  
Kenny Tiong Ping Chiet ◽  
Khairul Anuar Kassim ◽  
Siaw Yah Chong
Keyword(s):  
Shear Strength ◽  
Bacillus Subtilis ◽  
Treatment Condition ◽  
Soil Improvement ◽  
Soil Samples ◽  
Residual Soil ◽  
Facultative Anaerobe ◽  
Chemical Reagent ◽  
Chemical Reagents

Biomediated soil improvement, a promising new branch of microbial geotechnology; which involved multi disciplines has successfully attracted abundant attentions among researchers, geotechnical engineers, and other industries practitioners. Few of the researches were conducted to examine the potential implementation of this technique on tropical residue soil. However, the uncertainties outcomes and inconsistency of bio mediated soil improvement, especially on the clayed soil have made this technique remained at the laboratory stage. Therefore, this paper intended to provide better understanding of this technique by investigating the relation between the bacteria, cementation reagents, and tropical residue soil. The residual soil was mixed with facultative anaerobe bacteria, Bacillus Subtilis before it was compacted into a prefabricated PVC mould. The soil samples were treated with different treatment condition such as (1) control or untreated, (2) treated with cementation solution, (3) treated with bacteria only, and (4) treated with bacteria and Cementation reagent. A worth noting finding showed that the sample treated with bacteria and nutrient only has produced the highest increment of shear strength. This phenomenon might have been caused by the effect of the chemical reagent to the mineralogy of residue soil. The presence of the chemical reagents is believed to have weakened the shear strength of the tropical residual soil.

The Measurement of the ph Value of Rubber Latex

1930 ◽  
Vol 3 (4) ◽  
pp. 616-617
Author(s):  
J. G. Mackay
Keyword(s):  
Ph Value ◽  
Colorimetric Method ◽  
Colloid Chemistry ◽  
Rubber Latex ◽  
Blotting Paper ◽  
Ph Values ◽  
Satisfactory Method ◽  
Ph Range

Abstract E. A. Hauser has stated in his Gow Lectures on “The Colloid Chemistry of Rubber” that the most satisfactory method of determining the ph value of latex is by means of the Wulff ph tester. This instrument, which is manufactured by Messrs. F. and M. Lautenschlager, Münich 2, S.W. 6, determines ph value by a colorimetric method. Strips of gelatin which have been impregnated with various indicators to render them suitable for different portions of the ph range are supplied; the range of ph values has thus been subdivided into five zones, and a scale of comparison colors is supplied for each of these zones. The principle of the instrument is that gelatin is permeable only to the serum of a turbid dispersion such as latex; when an impregnated strip, or, as it is usually termed, an indicator foil, is dipped into the turbid liquid some serum liquid passes within and produces a change in the color of the indicator; at the same time the gelatin, by swelling, prevents any considerable diffusion of this colored portion of the serum into the bulk of the turbid dispersion. The foil is left in the turbid liquid for one minute and then dried in blotting paper. Its color is then compared with the series of colors on the comparison scale supplied.

Degradability of hexachlorocyclohexanes in water using ferrate (VI)

2014 ◽  
Vol 71 (3) ◽  
pp. 405-411 ◽  
Author(s):  
M. Homolková ◽  
P. Hrabák ◽  
M. Kolář ◽  
M. Černík
Keyword(s):  
Water Treatment ◽  
Environmental Pollution ◽  
Oxidation Potential ◽  
Stockholm Convention ◽  
Chemical Reagent ◽  
Ph Values ◽  
Ph Conditions ◽  
The Many ◽  
By Products ◽  
Main Factor

Regarding environmental pollution, the greatest public and scientific concern is aimed at the pollutants listed under the Stockholm Convention. These pollutants are not only persistent but also highly toxic with a high bioaccumulation potential. One of these pollutants, γ-hexachlorocyclohexane (γ-HCH), has been widely used in agriculture, which has resulted in wide dispersion in the environment. Remediation of this persistent and hazardous pollutant is difficult and remains unresolved. Of the many different approaches tested, to date, none has used ferrates. This is unexpected as ferrates are generally believed to be an ideal chemical reagent for water treatment due to their strong oxidation potential and the absence of harmful by-products. In this paper, the degradation/transformation of HCHs by ferrates under laboratory conditions was studied. HCH was degraded during this reaction, producing trichlorobenzenes and pentachlorocyclohexenes as by-products. A detailed investigation of pH conditions during Fe(VI) application identified pH as the main factor affecting degradation. We conclude that ferrate itself is unreactive with HCH and that high pH values, produced by K2O impurity and the reaction of ferrate with water, are responsible for HCH transformation. Finally, a comparison of Fe(VI) with Fe(0) is provided in order to suggest their environmental applicability for HCH degradation.

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