The dehydration of butanediol-2,3 over activated Morden bentonite has been investigated. Below 350 °C., liquid products butanone-2, isobutyraldehyde, and the isobutyral of butanediol-2,3 were produced. Butanone-2 was obtained in 86% yield. At higher temperatures, 450° to 700 °C., gaseous decomposition occurred. Only small amounts of butadiene were formed from the dry glycol while a 25% diolefin yield resulted using water vapour as diluent. The decomposition of dry butanone-2 over bentonite gave only traces of butadiene. Yields of diolefin increased using water as diluent, 44.8% being obtained at 700 °C. with a ketone–water molar ratio of 1 to 40. Butanone-2 was considered intermediate in the formation of butadiene from butanediol-2,3.

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Tertiary octyl, decyl, dodecyl, and hexadecyl mercaptans were investigated as modifiers in GR-S polymerizations. -The rate of disappearance of these modifiers follow-ed a first-order rate equation during the first half of the polymerization, in accordance with the theory of chain-transfer reactions, During the latter part of the reaction, an increased rate of disappearance generally occurred. A mechanism is suggested.The rate of disappearance increased rvith decreasing chain-length of the mercaptan. The intrinsic viscosities and molecular weight distributions of the polymers obtained at different conversions rvere related to the activity of each mercaptan as a modifier. Values for the regulating index of each mercaptan were calculaled.The slow rate of disappearance of tertiary hexadecyl mercaptan leads to the formation of polymer that is relatively homogeneous in molecular weight, and this mercaptan is therefore a desirable modifier. Hor.ever, after 50/s polymerization, the regulator action shows a marked acceleration, leading to the formation of progressively lower molecular weight polymer and resulting in a spread in the molecular weight distribution.