Elemental sulfur as a plasticizer for polysulfide polymers and other polymers

Abstract So-called elastic sulfur obtained by quick-quenching molten sulfur from a temperature of 250° C to a temperature of about −10° C is really a mixture of polymeric sulfur and monomeric S8 sulfur, the latter in a metastable condition, Quick-quenched sulfur is elastic because of the plasticizing effect of the liquid S8 sulfur on the polymeric sulfur. In this publication we show that large concentrations of S8 can exist dissolved in a liquid condition in other polymers where it also acts as a plasticizer. In many cases these compositions appear completely stable, i.e., there is no tendency for the dissolved sulfur to crystallize out. The best example is crosslinked polyethylene tetrasulfide polymers. These polymers can retain 40 per cent of dissolved sulfur in the form of liquid S8 over indefinitely long periods of time. We prove that the sulfur is in its elemental form by quantitative extraction with CS2. The specific volume of the dissolved sulfur shows it is in a liquid condition. The mechanical properties of the sulfur plasticized crosslinked polymers are just what would be expected from this type of structure. Preliminary information concerning sulfur in other polymers is presented.

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Scanning Electron Microscope Study of Bacteria on Mineral Surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090634 ◽

1976 ◽

Vol 34 ◽

pp. 130-131

Author(s):

V.K. Berry

Keyword(s):

Oxidation Reaction ◽

Electron Microscope Study ◽

Elemental Sulfur ◽

Thiobacillus Ferrooxidans ◽

Physical Contact ◽

Metal Sulfides ◽

Low Grade ◽

Mineral Surfaces ◽

Mineral Surface ◽

Scanning Electron Microscope Study

There are two strains of bacteria viz. Thiobacillus thiooxidansand Thiobacillus ferrooxidanswidely mentioned to play an important role in the leaching process of low-grade ores. Another strain used in this study is a thermophile and is designated Caldariella .These microorganisms are acidophilic chemosynthetic aerobic autotrophs and are capable of oxidizing many metal sulfides and elemental sulfur to sulfates and Fe2+ to Fe3+. The necessity of physical contact or attachment by bacteria to mineral surfaces during oxidation reaction has not been fairly established so far. Temple and Koehler reported that during oxidation of marcasite T. thiooxidanswere found concentrated on mineral surface. Schaeffer, et al. demonstrated that physical contact or attachment is essential for oxidation of sulfur.

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Chemical Conversion of SO2 in Low-Temperature Low-Pressure Oxyhydrogen Flames. 2. Mechanism of Formation of Elemental Sulfur

Физика горения и взрыва ◽

10.15372/fgv20160604 ◽

2016 ◽

Keyword(s):

Low Temperature ◽

Elemental Sulfur ◽

Chemical Conversion ◽

Low Pressure ◽

Mechanism Of Formation

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Elemental sulfur in Eddy County, New Mexico

Circular ◽

10.3133/cir628 ◽

1970 ◽

Author(s):

Jim S. Hinds ◽

Richard R. Cunningham

Keyword(s):

New Mexico ◽

Elemental Sulfur

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Faculty Opinions recommendation of Sulfite-oxido-reductase is involved in the oxidation of sulfite in Desulfocapsa sulfoexigens during disproportionation of thiosulfate and elemental sulfur.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1015313.196313 ◽

2003 ◽

Author(s):

Bruce Rittmann

Keyword(s):

Elemental Sulfur

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Identification of Taste and Odour Compounds from Western Lake Ontario

Water Quality Research Journal ◽

10.2166/wqrj.1984.010 ◽

1984 ◽

Vol 19 (1) ◽

pp. 111-118 ◽

Cited By ~ 6

Author(s):

B.G. Brownlee ◽

D.S. Painter ◽

R.J. Boone

Keyword(s):

Water Supply ◽

Water Samples ◽

Elemental Sulfur ◽

Lake Ontario ◽

Direct Link ◽

Municipal Water Supply ◽

Municipal Water ◽

Western Lake ◽

Odour Concentration

Abstract During August, 1983 geosmin was identified in a municipal water supply drawn from western Lake Ontario. The geosmin concentrations were 0.01-0.07 μg L-1, within the range for threshold odour concentration of 0.01-0.2 μg L-1. 2-Methylisoborneol was not detected. The odour 'event' coincided with a dieoff of Cladophora in the lake, but we were not able to establish a direct link between the dieoff and geosmin production. Decomposing Cladophora in shoreline areas produced a strong odour in the air. 3-Methylindole, elemental sulfur, dimethyl tetrasulfide, and dimethyl pentasulfide were tentatively identified in water samples collected from these areas, but geosmin and 2-methylisoborneol were not detected.

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