Vulcan Chemical Technologies

Vulcan Chemical Technologies, Inc. using the Calloway subsidiary and brand name... 

Today, high quality, well-designed generating equipment is available for this niche market, which can safely yield high conversion efficiencies ( 95% CIO2) from the generation reaction (e.g., Rio Linda equipment from Vulcan Chemical Technologies, Inc.). 

Improvement in the processing and vulcanized qualities of a range of systems have been reported over the past decades. Modification of natural rubber, due to work in the British Rubber Producers Research Association, yields some of the most striking applications of microgel. A detailed study at the MV Lomonosov Institute of Fine Chemical Technology, in Moscow, on the effect of microgels on mechanical properties of cis-polyisoprene and butadiene-styrene rubbers extensively illustrates the properties of blends from latex combination of microgel and conventional or linear systems.(31)... 

The progress of chemistry, associated with the industrial revolution, created a new scope for the preparation of novel polymeric materials based on renewable resources, first through the chemical modification of natural polymers from the mid-nineteenth century, which gave rise to the first commercial thermoplastic materials, like cellulose acetate and nitrate and the first elastomers, through the vulcanization of natural rubber. Later, these processes were complemented by approaches based on the controlled polymerization of a variety of natural monomers and oligomers, including terpenes, polyphenols and rosins. A further development called upon chemical technologies which transformed renewable resources to produce novel monomeric species like furfuryl alcohol. 

Tipova, N. PhD Thesis Investigation of Zinc Stearate as Activator of the Accelerated Sulfur Vulcanization with a view to Zinc Reducing in the Rubber Compoimds , 2006, University of Chemical Technology and Metallurgy, Sofia (in Bulgarian). 

Rubber processing chemicals are used extensively to impart performance and processability to rubber and the products made thereof. These chemicals are typically organic compoimds but several inorganic materials are also included under the umbrella of rubber chemicals. The rubber compoimd is described as a mixture of one or more rubber polymers (elastomers) with a combination of one or more of fillers, oils, and rubber chemicals (see Rubber Compoundb g). The compoimd, once vulcanized, provides technologically useful properties, such as may be applied to tires, hoses, belts, tracks, and a variety of mechanical goods. 

Despite of 150-year s history of vulcanization process, it is impossible to consider that fundamental and applied researches in direction of vulcanization systems perfection are completed. For today one of the ways of rubbers properties improvement is the synthesis and application of the new chemicals-additives, including, vulcanization active, that is connected, first of all, with reduction of global stocks of zinc ores as basic raw material for reception of traditional activator - zinc oxide. Besides, modem increase of industrial potential and the accumulation of big quantity wastes derivate the problems of ecological character, which require the emergency decision. Therefore creation of resourcesaving technologies of the new compounds reception from products of secondary raw material processing has paramount importance. 

The principal commercial uses of sulfur monochloride are in the manufacture of lubricant additives and vulcanizing agents for rubber (147,154,155) (see Lubrication and lubricants Rubber chemicals). The preparation of additives for wear and load-bearing improvement of lubricating oils is generally carried out in two steps and the technology is described in numerous patents (155) (see Sulfurization and sulfchlorination). 

Soft flexible rubbery behavior depends on long flexible polymer molecules in the form of random coils. Strength, heat and chemical resistance depend on attachment between the coils. Conventional rubber chemistry uses vulcanization, permanent thermoset primary covalent cross-links, usually by sulfiir plus metal oxides, to hold the coils together but this makes processing more difficult, and recycling very difficult. In the past 40 years, this technology has been supplemented by the... 

OTHER COMMENTS used as an intermediate and chlorinating agent in the manufacture of organic chemicals, sulfur dyes, synthetie mbbers, and insecticides used as a cross-linking catalyst in polymer technology use for eold vulcanizing of thin mbber articles useful as a solvent for sulfur and sulfur compounds. 

In addition to use of organic chemicals, mbbers can be devulcanized by means of inorganic compounds. Discarded tires and tire factory waste were devulcanized by desulfurization of suspended mbber vulcanizate cmmb (typically 10 30 mesh) in a solvent such as toluene, naphtha, benzene, or cyclohexane in the presence of sodium (Myers et al., 1997). The alkali metal cleaves mono-, di-, and polysulfidic crosslinks of the swollen and suspended vulcanized mbber crumb at around 300°C in the absence of oxygen. However, this process may not be economical because the process involves swelling of the vulcanized mbber crumb in an organic solvent where the metallic sodium in molten condition should reach the sulfidic crosslink sites in the mbber cmmb. Also, solvent may cause pollution and be hazardous. A technology was also proposed to reclaim powder mbbers using an iron oxide phenyl hydrazine based catalyst (Kawabata et al., 1981) and copper(I) chloride-tributylamine catalyst (Kawabata et al., 1979). 

Blends of elastomers are of technological and commercial importance since they allow the user to access properties of the final blended and vulcanized elastomer that are not accessible from a single, commercially available elastomer alone. These potentially improved properties include chemical, physical, and processing benefits. In reality, all blends show compositionally correlated changes in all of these properties compared to the blend components. The technology of elastomer blends is largely focused on the choice of individual elastomers and the creation of the blends to achieve a set of final properties. This chapter shows some of the instances of the uses of elastomer blends. Empirical guidelines for the creation of novel blends of elastomers is a comparatively more difficult proposition. 

---