1	A Study on Guerbet Branching By: Anthony J. O’Lenick, Jr.
2	Derivative Preparation Critical Considerations: Selection of the hydrophobe Number of carbon atoms present in the hydophobe Branching effects liquidity & surface-active properties What is the effect of branching on oil phases - particularly esters?
3	Factors Effecting Liquidity Unsaturation rancidity Branching purity consistency
4	"Marcel Guerbet ¹ first synthesized" Marcel Guerbet ¹ first synthesized Reaction sequence relates to Aldol Reaction Occurs at high temperatures, under catalytic conditions
5	Reaction Sequence⁴ 1. The reaction takes place without catalyst, but it is strongly catalyzed by addition of hydrogen transfer catalysts. 2. At low temperatures 130-140 ^oC the rate-limiting step is the oxidation process ( i.e. formation of the aldehyde). 3. At somewhat higher temperatures 160-180 ^oC the rate-limiting step is the Aldol Condensation. 4. At even higher temperatures other degradative reactions occur and can become dominant.
6	Reactive Mechanism The product is an alcohol with twice the molecular weight of the reactant, minus a mole of water. The reaction proceeds sequentially : A) oxidation of alcohol to aldehyde. B) Aldol condensation after proton extraction. C) dehydration of the Aldol product. D) hydrogenation of the allylic aldehyde.
7	Guerbet Alcohols High molecular weight, therefore: low irritation properties. branched, liquid to extremely low temperatures. low volatility primary alcohols -reactive and can be used to make many derivatives. useful as superfatting agents to re-oil the skin and hair. good lubricants.
8	"exhibit oxidative stability at elevated..." exhibit oxidative stability at elevated temperatures excellent color initially and at elevated temperatures exhibit improved stability over unsaturated products in many formulations.
9	Melting Points Various Acids
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14	Ester Titer Point Ester having 32 carbon atoms 16 in acid / 16 in alcohol
15	Ester Titer Point Ester having 40 Carbon Atoms 20 in Acid / 20 in Alcohol
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18	"Material" Material Guerbet Acid Guerbet Alcohol Hexyldecanoic (C16) 17 C - 8 C Octyldodecanoic (C20) 34 C 0 C
19	Melting Points Guerbet vs Linear Alcohols
20	Melting Points Guerbet vs Linear Acids
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22	Ester Titer Points Compared by alcohol/acid type and number of carbon atoms
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24	Class 1 (products having 32 carbon atoms) OH/AC Designation Type A B C D E Cetyl Palmitate (L/L) I S S I S Hexyldecyl Palmitate (G/L) I S S I S Cetyl Hexyldecanonate (L/G) I S S I S Hexyldecyl hexyldecanonte (G/G) I S S I S Legend s = soluble i = insoluble Solvent Designations: A is water B is isopropanol C is cyclomethicone D is dimethicone E is mineral oil
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26	"The highest titer point ester..." The highest titer point ester was the one based upon both linear alcohol and linear acid. The incorporation of a Guerbet branch in the alcohol portion of the molecule increased the titer point, resulting in an ester that is slushy below it's titer point, it was however pourable. The use of a Guerbet acid and a linear alcohol resulted in a product that had a much lower titer point. The ester with the lowest titer point was made with both a Guerbet alcohol and Guerbet acid.
27	Dry Times 32 carbon atoms esters
28	Dry Times 40 Carbon atom esters
29	Drying Time Comparison on skin for esters with one or two Guerbet components and 32 and 40 carbons
30	"The hardest" The hardest, most crystalline ester in each class was the one based upon both linear alcohol and linear acid. The incorporation of a Guerbet branch in the alcohol portion of the molecule, while increasing the titer point, makes the ester slushy below it's titer point. The use of a Guerbet acid and a linear alcohol resulted in a product which had a much lower titer point, but was slushy below it's titer point. Only the ester made with both a Guerbet alcohol and Guerbet acid remained liquid and clear below 0^oC.