Amylene polymerization

To obtain light ends conversion, alkylation and polymerization are used to increase the relative amounts of liquid fuel products manufactured. Alkylation converts olefins, (propylene, butylenes, amylenes, etc.), into high octane gasoline by reacting them with isobutane. Polymerization involves reaction of propylene and/or butylenes to produce an unsamrated hydrocarbon mixture in the motor gasoline boiling range. 

NOTE.—The alcohol to be used in this experiment is now made by the Standard Oil Co. of New Jersey and is available commercially. Secondary alcohols, of the general formula R2CHOH, lose water more readily than primary alcohols, RCH2OH. For this reason sulphuric acid diluted with water can be used. If the concentrated acid is used the unsaturated hydrocarbon is polymerized to di- and tri-amylenes. 

NOTE.—If concentrated sulphuric add is used in this preparation, a large part of the amylene is polymerized. If a more dilute acid is used than that recommended, the reaction requires a longer time. Sodium hydroxide is added to the distillate to precipitate the alcohol which is dissolved in the water. Alcohols in general are less soluble in a solution of bases than in water. 

AMYLENE or a-n-AMYLENE (109-67-1) Forms explosive mixture with air (flash point 0°F/— 18°C). Able to polymerize on standing. Incompatible with strong acids, oxidizers. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

Sulfuric acid and isoamylene under suitable conditions yield diisoamylene also. This polymerization reaction is used commercially in the formation of synthetic rubber from the octadiens. The specific action of the particular catalyst employed is shown also by the fact that iso-propyl bromide dissociated at the temperature of boiling amylene in the presence of asbestos, while the n-bromide did not. [D. Konowalow, Ber. 18, 2808 (1885).]... 

Additives An advantage of organocatalytic ROP of lactide is that the synthesis is not oxygen sensitive. However, the reagents and solvents have to be extremely dry, since every water molecule initiates and deactivates/reacts with the catalysts, e.g. the strong bases. The initiation of poly(lactic acid) homopolymer by water is especially unwanted when polymerizing well-defined copolymers using a macroinitiator. Acids such as benzoic acid are used for a rapid termination of the polymerization. Chloroform and dichloromethane are commonly used as solvents, since lactide is easily dissolved in these solvents. Chloroform stabilized with amylenes rather than with ethanol should be used. 

These hydrocarbon resins are produced from the cationic polymerization of mixed olefin and diolefin feedstocks. These raw materials consist of C5 feedstocks such as pentenes, pentadiene, isoprene, and amylene, and C6 streams of hexenes and hexa-dienes. 

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