Reactions catalyzed by minerals. Part II. Chain termination in free‐radical polymerizations

Solomon, D. H.; Swift, Jean D.

doi:10.1002/app.1967.070111216

Cited by 66 publications

(47 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Kaolinite and polyphosphate treated kaolinite, (Solomon and Swift, 1967), were processed into tMeasured at 21~ at 12 rpm using spindle 4 on a Brookfield viscometer. a rubber mix using the following formula: SBR 1502, 500 parts (by weight); sulfur, 15 parts; cyclohexyl benzothionyl sulfide, 10 parts; zinc oxide, 25 parts; coumarone resin, 37.5 parts; clay, 260 parts.…”

Section: Measurement Of Properties Of Kaolinite Filled Rubbermentioning

confidence: 99%

“…In fact the chemical activity is of such magnitude that it is the basis for selecting kaolinite as a base for catalyst preparations and as a component of pressure sensitive copying paper (Green, 1952). In other applications, for example when used as a filler or extender in rubber (Solomon and Swift, 1967) or as a diluent for insecticide powders (Benesi et al, 1959) the chemical activity must be controlled if satisfactory products are to be obtained.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Acid-Base Interactions and the Properties of Kaolinite in Non-Aqueous Media

Solomon¹

1972

Clays and clay miner.

Self Cite

View full text Add to dashboard Cite

Abstract--In non-aqueous systems, kaolinite can show, in addition to the physical interactions, considerable chemical activity. This study considers the chemical reactions that can occur at the kaolinite surface and explains these reactions in terms of acid-base interactions. In certain applications the chemical activity must be controlled if satisfactory products are to be obtained; for example, when kaolinite is used as a filler in rubber or as a diluent for insecticide powders. The concept of acid-base interactions is used to explain rheological and film properties in kaolinite-organic systems. The strength of the surface acid sites of kaolinite varies with the moisture content. At 1% moisture the surface is equivalent to 48% sulphuric acid whereas at 0% it is equivalent to 90% sulphuric acid. Therefore, the moisture level is extremely important and dry kaolinite will promote or catalyze many chemical reactions and where acid-base interactions are involved the presence of even small amounts of water usually retards or inhibits the reaction. Several examples explaining these interactions are given in the paper.

show abstract

Section: Measurement Of Properties Of Kaolinite Filled Rubbermentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Acid-Base Interactions and the Properties of Kaolinite in Non-Aqueous Media

Solomon¹

1972

Clays and clay miner.

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, it was recognized that minerals could modulate the rates of epimerization. In particular, acidic surface sites of certain clay types were shown to catalyze isomerization, rearrangement, and hydrogen exchange reactions (Solomon and Swift, 1967;Sieskind et al, 1979;Saxby et al, 1992). Alexander et al (1984) proposed an epimerization mechanism that proceeded through a planar sp 2 hybridized intermediate.…”

Section: Discussion Of Possible Mechanisms For Mineral Preservation Omentioning

confidence: 99%

Testing the ancient marine redox record from oxygenic photosynthesis to photic zone euxina

French¹

2015

View full text Add to dashboard Cite

Tracing the evolution of Earth's redox history is one of the great challenges of geobiology and geochemistry. The accumulation of photosynthetically derived oxygen transformed the redox state of Earth's surface environments, setting the stage for the subsequent evolution of complex life. However, the timing of the advent of oxygenic photosynthesis relative to the Great Oxidation Event (GOE; ~2.4 Ga) is poorly constrained. After the deep ocean became oxygenated in the early Phanerozoic, hydrogen sulfide, which is toxic to most aerobes, may have transiently accumulated in the marine photic zone (i.e. photic zone euxinia; PZE) during mass extinctions and oceanic anoxic events. Here, the molecular fossil evidence for oxygenic photosynthesis and eukaryotes is reevaluated, where the results imply that currently existing lipid biomarkers are contaminants. Next, the stratigraphic distribution of green and purple sulfur bacteria biomarkers through geologic time is evaluated to test whether these compounds reflect a water column sulfide signal, which is implicit in their utility as PZE paleoredox proxies. Results from a modern case study underscore the need to consider allochthonous and microbial mat sources and the role of basin restriction as alternative explanations for these biomarkers in the geologic record, in addition to an autochthonous planktonic source.

show abstract

“…On the other hand, clays are known to be free radical scavengers and traps. [21] The clay minerals inhibit the free radical reactions by absorption of the propagating or initiating radicals to the Lewis acid sites of clay surface. The radicals then undergo termination and/or chain-transfer reactions by electron transfer to Lewis acid site, which are partly responsible for lower MW and broader MWD.…”

Section: Molecular Weight and Its Distribution Of Ps Extractedmentioning

confidence: 99%

Intercalated PS/Na⁺‐MMT Nanocomposites Prepared by Ultrasonically Initiated In Situ Emulsion Polymerization

Wang

Chen

2005

Macro Materials & Eng

View full text Add to dashboard Cite

Summary: A new technique, ultrasonically initiated in situ emulsion polymerization, was employed to prepare intercalated polystyrene/Na+‐MMT nanocomposites. FTIR, XRD, and TEM results confirm that the hydrophobic PS can easily intercalate into the galleries of hydrophilic montmorillonite via ultrasonically initiated in situ emulsion polymerization, taking advantages of the multi‐effects of ultrasonic irradiation, such as dispersion, pulverization, activation, and initiation. Properly reducing SDS concentration is beneficial to widen the d‐spacing between clay layers. However, the Na+‐MMT amount has little effect on the d‐spacing of nanocomposites. The glass transition temperature of nanocomposites increased as the percentage of clay increased, although the average molecular weight of PS decreased, and the decomposition temperature of the 1obtained nanocomposites moves to higher temperature.TEM of PS/Na+‐MMT nanocomposite prepared by ultrasonically initiated in situ emulsion polymerization.magnified imageTEM of PS/Na+‐MMT nanocomposite prepared by ultrasonically initiated in situ emulsion polymerization.

show abstract

Reactions catalyzed by minerals. Part II. Chain termination in free‐radical polymerizations

Cited by 66 publications

References 11 publications

Acid-Base Interactions and the Properties of Kaolinite in Non-Aqueous Media

Acid-Base Interactions and the Properties of Kaolinite in Non-Aqueous Media

Testing the ancient marine redox record from oxygenic photosynthesis to photic zone euxina

Intercalated PS/Na⁺‐MMT Nanocomposites Prepared by Ultrasonically Initiated In Situ Emulsion Polymerization

Contact Info

Product

Resources

About

Reactions catalyzed by minerals. Part II. Chain termination in free‐radical polymerizations

Cited by 66 publications

References 11 publications

Acid-Base Interactions and the Properties of Kaolinite in Non-Aqueous Media

Acid-Base Interactions and the Properties of Kaolinite in Non-Aqueous Media

Testing the ancient marine redox record from oxygenic photosynthesis to photic zone euxina

Intercalated PS/Na+‐MMT Nanocomposites Prepared by Ultrasonically Initiated In Situ Emulsion Polymerization

Contact Info

Product

Resources

About

Intercalated PS/Na⁺‐MMT Nanocomposites Prepared by Ultrasonically Initiated In Situ Emulsion Polymerization