Divinyl acetylene

Polychloroprene rubber (CR) is the most popular and versatile of the elastomers used in adhesives. In the early 1920s, Dr. Nieuwland of the University of Notre Dame synthesized divinyl acetylene from acetylene using copper(l) chloride as catalyst. A few years later, Du Pont scientists joined Dr. Nieuwland s research and prepared monovinyl acetylene, from which, by controlled reaction with hydrochloric acid, the chloroprene monomer (2-chloro-l, 3-butadiene) was obtained. Upon polymerization of chloroprene a rubber-like polymer was obtained. In 1932 it was commercialized under the tradename DuPrene which was changed to Neoprene by DuPont de Nemours in 1936. 

Peroxidizable hazard on storage Isopropyl ether Divinyl acetylene Vinylidene chloride Potassium metal Sodium amide... 

Some chemicals are susceptible to peroxide formation in the presence of air [10, 56]. Table 2.15 shows a list of structures that can form peroxides. The peroxide formation is normally a slow process. However, highly unstable peroxide products can be formed which can cause an explosion. Some of the chemicals whose structures are shown form explosive peroxides even without a significant concentration (e.g., isopropyl ether, divinyl acetylene, vinylidene chloride, potassium metal, sodium amide). Other substances form a hazardous peroxide on concentration, such as diethyl ether, tetrahydrofuran, and vinyl ethers, or on initiation of a polymerization (e.g., methyl acrylate and styrene) [66]. 

Shimizuya Kimura(Ref 6) proposed a smoke-producing mixr contg as the principal ingredient a product obtained by treating CaHa polymer (consisting mainly of divinyl-acetylene) with 5-6 atoms of chlorine at 60 70°. Other ingredients of the smoke mixt are Al, KClOj and kieselguhr... 

Group 1 — Test every 3 months Divinyl acetylene Isopropyl ether Potassium Sodium amide Vinylidene chloride... 

Diethylene glycol ether Dimethyl divinyl acetylene (disopropenyl acetylene) Dimethylhydrazine, un symmetrical Enzymes, except diagnostic substances... 

Disalicylal ethylenediamine Ditolyl guanidine (o-) Divinyl acetylene Docosane (n-)... 

DIVINYLACETYLENE or DIVINYL-ACETYLENE A (821-08-9) CsH Stored material rapidly forms unstable and potentially explosive peroxides in air. Violent reaction with strong oxidizers strong acids oleum. Discard within 3 months. 

Based on the above, for creation of new effective bum eatalysts and softeners of SRF, before us there was a task to s mthesize and investigate unknown earlier derivatives of ferroeene containing mono- and divinyl-acetylene alcohols. 

Abstract Ab initio crystal orbital calculations have been perfomed on the equilibrium geometries and on parts of the harmonic force field of polyyne and polydiacetylene. Results obtained on the polymers are compared with conventional MO calculations on oligoynes and on divinyl-acetylene. 

Details polychloroprene was Invented by DuPont scientists on April 17,1930 after Dr. Elmer K. Bolton of DuPont laboratories attended a lecture by Fr. Julius Arthur NIeuwland, a professor of chemistry at the University of Notre Dame. Fr. Nieuwland s research was focused on acetylene chemistry and during the course of his work he produced divinyl acetylene, a jelly that firms Into an elastic compound similar to rubber when passed over sulfur dichlorlde. After DuPont purchased the patent rights from the university, V fellace Carothers of DuPont took over commercial development of Nieuwland s discovery in collaboration with NIeuwland himself. DuPont focused on monovinyl acetylene and reacted the substance with hydrogen chloride gas, manu cturing chloroprene. ... 

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