Recent Developments in Synthetic Rubber Latex

1961 ◽  
Vol 34 (5) ◽  
pp. 1501-1520 ◽  
Author(s):  
L. H. Howland ◽  
R. W. Brown
Keyword(s):  
Amino Groups ◽  
Rubber Latex ◽  
Low Viscosity ◽  
Polar Groups ◽  
Synthetic Rubber ◽  
Polymerization System ◽  
Recent Developments ◽  
The Government ◽  
Solids Content ◽  
Made In

Abstract Progress has proceeded at a good rate since the close of the Government Program in the spring of 1955. Improved latexes have been made, and the technology of manufacture and of application has advanced. Also progress has been made in fundamental latex research. Some of the newer latexes representing the more important advances are those involving functonal groups derived from the use of unsaturated monomers such as those containing amino groups and carboxy groups in the polymerization system, those from solid rubbers by the solvent emulsion technique, and those of higher solids content including the agglomerated latexes giving 68 per cent minimum solids at low viscosity. Some of the applications of greatest growth are : 1. Carpet backing involving both sulfur curing and so-called self-curing (noncured) elastomer latexes. The latter obtain strength from polar groups including functional (carboxyl) groups and/or fairly high styrene content. 2. Foam sponge backed carpets. In 1954 it was suggested that synthetic rubber latexes would have a permanent place in our economy. This has now come to pass, and natural latex is decreasing in volume compared to total synthetic rubber latex consumption. It now appears that by forming a latex from cis polyisoprene (synthetic natural rubber) and adding it to our list of latexes, that our country could probably become independent of the natural product.

The Indian Farming-Community and their Health-Concerns for a Sustainable Agriculture

2022 ◽  
Vol 13 (1) ◽  
pp. 0-0
Keyword(s):  
Developing Countries ◽  
Well Being ◽  
Intervention Strategies ◽  
Health Concerns ◽  
Work Related ◽  
Farming Community ◽  
Recent Developments ◽  
Health Disorders ◽  
The Government ◽  
Made In

The exposure of farmers to agricultural hazards and risks has been increased in their work-places with the recent developments in agricultural sectors in most of the developing countries. This higher expose may be due to the enhanced need in meeting the food as well as monetary demand of farming house-holds. The agricultural-productivity has also been reduced in developing countries because of the exposure of farmers to work-related stresses affecting their well-being. Thus, an attempt was made in this study for exploring the mental-health disorders among the farmers and the farming-community in the state of Odisha in India for undertaking possible intervention strategies by the government and competent authorities.

Processing Characteristics of Synthetic Tire Rubber

1943 ◽  
Vol 16 (1) ◽  
pp. 203-208
Author(s):  
B. S. Garvey ◽  
M. H. Whitlock ◽  
J. A. Freese
Keyword(s):  
Natural Rubber ◽  
Laboratory Tests ◽  
Laboratory Methods ◽  
Tire Rubber ◽  
Synthetic Rubber ◽  
Different Types ◽  
Full Production ◽  
The Government ◽  
Processing Properties ◽  
Made In

Abstract The processing characteristics of synthetic tire rubber, such as is being made in the government program, are sufficiently different from those of natural rubber to require different laboratory and factory treatment. Since the laboratory tests used for the evaluation of processing characteristics were developed for natural rubber, it is not surprising that they are not so satisfactory for synthetic rubber. The purpose of this paper is to discuss some of the characteristics of synthetic tire rubber, and to describe certain tests which have been found useful for evaluating different types of synthetic rubber or different compounds of the same synthetic rubber. In the course of the development, it has been necessary to evaluate rubbers with a wide variety of processing properties. As production has increased, there has been less variation in the output from any one plant. As the newer and larger plants come into full production, we can expect greater uniformity from each plant and between different plants. We can also look forward to gradual improvements in processing characteristics. This development will be ensured by adequate laboratory methods for evaluating processing properties. This discussion is based in part on variations encountered in development work and in part on the properties of the present production from one plant.

Some Recent Developments in Sewage Sludge Pumping

1988 ◽  
Vol 20 (4-5) ◽  
pp. 227-236
Author(s):  
J. H. Lohmann ◽  
W. F. Garber
Keyword(s):  
Sewage Sludge ◽  
Treatment Plant ◽  
Rheological Characteristics ◽  
Volatile Content ◽  
Collection System ◽  
Positive Displacement ◽  
Low Viscosity ◽  
Recent Developments ◽  
Cylinder Piston ◽  
Pumping Equipment

The pumping of sewage sludge solids is reviewed in terms of handling high and low viscosity materials with solids concentrations varying from about 4 % to perhaps 50 %. Knowledge of rheological characteristics including thixotropy is necessary in designing pumping systems with sludge solids percentages, volatile content, particle size, abrasives content and temperatures being variables which could change pump types found suitable from facility to facility. The characteristics of a sewage collection system is also important in determining pumping parameters needed in a treatment plant. Solids handling equipment from other industries have made significant contributions to sewage solids pumping in recent years. Included are moyno-type progressing cavity screw-centrifugal, recessed impeller rotation piston positive displacement, and two cylinder piston S-transfer positive displacement pumps. Pumping equipment used in the F.R.G. and in Southern California in the U.S.A. is remarkably similar. These types of pumps offer the possibility of designing optimum solids dewatering and transfer systems.

Contributory Fault under International Law: A Gateway for Human Rights in ISDS?

2020 ◽  
Author(s):  
Farouk El-Hosseny ◽  
Patrick Devine
Keyword(s):  
Human Rights ◽  
International Law ◽  
Multinational Enterprises ◽  
Indigenous Rights ◽  
Business And Human Rights ◽  
Investment Treaty ◽  
Recent Developments ◽  
The Government ◽  
Bear Creek ◽  
Shed Light

Abstract The intersection between foreign investment and human rights is gaining attention, as is evident from an increasing number of investment treaty awards analysing legal issues relating to human rights. In the recent International Centre for the Settlement of Investment Disputes (ICSID) arbitration of Bear Creek v Peru, Philippe Sands QC posited, in a dissenting opinion, that the investor’s contribution to events—ie protests against its allegedly adverse environmental impact and disregard of indigenous rights, namely resulting from its ‘inability to obtain a “social licence”’—which led to the unlawful expropriation of its investment, was ‘significant and material’. He further noted that the investor’s ‘responsibilities are no less than those of the government’ and found that damages should thus be reduced. Last year, the Netherlands adopted a new model bilateral investment treaty (BIT), which allows tribunals to ‘take into account non-compliance by the investor with the UN Guiding Principles on Business and Human Rights and the OECD Guidelines for Multinational Enterprises’ when assessing damages. These recent developments shed light on how states and tribunals, as part of their decision-making process, can take into account human rights in practice, and crucially in respect of damages analyses. By first dissecting the concept of contributory fault, then shedding light on the intersection of investment treaty law and human rights, as elucidated in recent jurisprudence, this article questions whether there now exists a gateway for human rights obligations (soft or hard) in the investment treaty arbitration realm through the concept of contributory fault.

scholarly journals Alternative of bone china and porcelain as ceramic hand molds for rubber latex glove films formation via dipping process

2020 ◽  
Vol 59 (1) ◽  
pp. 523-537
Author(s):  
Chaturaphat Tharasana ◽  
Aniruj Wongaunjai ◽  
Puwitoo Sornsanee ◽  
Vichasharn Jitprarop ◽  
Nuchnapa Tangboriboon
Keyword(s):  
Thermal Expansion ◽  
Flexural Strength ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Mold Surface ◽  
Rubber Latex ◽  
Latex Glove ◽  
Bone China ◽  
Synthetic Rubber ◽  
Natural And Synthetic

AbstractIn general, the main compositions of porcelain and bone china composed of 54-65%wt silica (SiO2), 23-34% wt alumina (Al2O3) and 0.2-0.7%wt calcium oxide (CaO) suitable for preparation high quality ceramic products such as soft-hard porcelain products for teeth and bones, bioceramics, IC substrate and magneto-optoelectroceramics. The quality of ceramic hand mold is depended on raw material and its properties (pH, ionic strength, solid-liquid surface tension, particle size distribution, specific surface area, porosity, density, microstructure, weight ratio between solid and water, drying time, and firing temperatures). The suitable firing conditions for porcelain and bone china hand-mold preparation were firing at 1270°C for 10 h which resulted in superior working molds for making latex films from natural and synthetic rubber. The obtained fired porcelain hand molds at 1270°C for 10 h provided good chemical durability (10%NaOH, 5%HCl and 10%wtNaCl), low thermal expansion coefficient (5.8570 × 10−6 (°C−1)), good compressive (179.40 MPa) and good flexural strength (86 MPa). While thermal expansion coefficient, compressive and flexural strength of obtained fired bone china hand molds are equal to 6.9230 × 10−6 (°C−1), 128.40 and 73.70 MPa, respectively, good acid-base-salt resistance, a smooth mold surface, and easy hand mold fabrication. Both obtained porcelain and bone china hand molds are a low production cost, making them suitable for natural and synthetic rubber latex glove formation.

scholarly journals Recent advances in the electrochemical construction of heterocycles

2014 ◽  
Vol 10 ◽  
pp. 2858-2873 ◽  
Author(s):  
Robert Francke
Keyword(s):  
Heterocyclic Compounds ◽  
Elevated Temperatures ◽  
Ring Formation ◽  
Environmentally Benign ◽  
Heterocyclic Chemistry ◽  
Ambient Conditions ◽  
Recent Developments ◽  
Strong Acids ◽  
Selection Of ◽  
Made In

Due to the fact that the major portion of pharmaceuticals and agrochemicals contains heterocyclic units and since the overall number of commercially used heterocyclic compounds is steadily growing, heterocyclic chemistry remains in the focus of the synthetic community. Enormous efforts have been made in the last decades in order to render the production of such compounds more selective and efficient. However, most of the conventional methods for the construction of heterocyclic cores still involve the use of strong acids or bases, the operation at elevated temperatures and/or the use of expensive catalysts and reagents. In this regard, electrosynthesis can provide a milder and more environmentally benign alternative. In fact, numerous examples for the electrochemical construction of heterocycles have been reported in recent years. These cases demonstrate that ring formation can be achieved efficiently under ambient conditions without the use of additional reagents. In order to account for the recent developments in this field, a selection of representative reactions is presented and discussed in this review.

China’s shadow banking sector: beneficial or harmful to economic growth?

2015 ◽  
Vol 7 (4) ◽  
pp. 421-445 ◽  
Author(s):  
James R. Barth ◽  
Tong Li ◽  
Wen Shi ◽  
Pei Xu
Keyword(s):  
Economic Growth ◽  
Banking Sector ◽  
Commercial Banking ◽  
Global Perspective ◽  
Shadow Banking ◽  
Content Type ◽  
Wide Range ◽  
Recent Developments ◽  
Major Factors ◽  
Made In

Purpose – The purpose of this paper is to examine recent developments pertaining to China’s shadow banking sector. Shadow banking has the potential not only to be a beneficial contributor to continued economic growth, but also to contribute to systematic instability if not properly monitored and regulated. An assessment is made in this paper as to whether shadow banking is beneficial or harmful to China’s economic growth. Design/methodology/approach – The authors start with providing an overview of shadow banking from a global perspective, with information on its recent growth and importance in selected countries. The authors then focus directly on China’s shadow banking sector, with information on the various entities and activities that comprise the sector. Specifically, the authors examine the interconnections between shadow banking and regular banking in China and the growth in shadow banking to overall economic growth, the growth in the money supply and the growth in commercial bank assets. Findings – Despite the wide range in the estimates, the trend in the size of shadow banking in China has been upward over the examined period. There are significant interconnections between the shadow banking sector and the commercial banking sector. Low deposit rate and high reserve requirement ratios have been the major factors driving its growth. Shadow banking has been a contributor, along with money growth, to economic growth. Practical implications – The authors argue that shadow banking may prove useful by diversifying China’s financial sector and providing greater investments and savings opportunities to consumers and businesses throughout the country, if the risks of shadow banking are adequately monitored and controlled. Originality/value – To the authors’ knowledge, this paper is among the few to systematically evaluate the influence of shadow banking on China’s economic growth.

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