Poly fatty acid terminated

Fatty acids have also been converted to difunctional monomers for polyanhydride synthesis by dimerizing the unsaturated erucic or oleic acid to form branched monomers. These monomers are collectively referred to as fatty acid dimers and the polymers are referred to as poly(fatty acid dimer) (PFAD). PFAD (erucic acid dimer) was synthesized by Domb and Maniar (1993) via melt polycondensation and was a liquid at room temperature. Desiring to increase the hydrophobicity of aliphatic polyanhydrides such as PSA without adding aromaticity to the monomers (and thereby increasing the melting point), Teomim and Domb (1999) and Krasko et al. (2002) have synthesized fatty acid terminated PSA. Octanoic, lauric, myristic, stearic, ricinoleic, oleic, linoleic, and lithocholic acid acetate anhydrides were added to the melt polycondensation reactions to obtain the desired terminations. As desired, a dramatic reduction in the erosion rate was obtained (Krasko et al., 2002 Teomim and Domb, 1999). 

Polyanhydrides with hydrophobic fatty acid terminals have been reported (Teomim and Domb, 2001) as shown in Scheme 5.4. In this reaction, SA was polymerised with acetic anhydride to form prepolymer of poly(sebacic anhydride) (PSA). It was hydro-phobised by the interchange of polyanhydride chain with previously prepared fatty acid anhydrides of acetic acid. 

Scheme 5.4 Synthesis of nonlinear fatty acid terminated poly(sebacic anhydride).

Poly (1,2-propylene adipate) = 4, mixed fatty acid-terminated... 

Crooks et al. reported the transfer of amine-functionalized poly(amidoamine) dendrimers into toluene containing dodecanoic acid [198], The method is based on the formation of ion pairs between the fatty acids and the terminal amine-groups. These dendrimer-fatty acid complexes resemble unimolecular inverted micelles and could be used as phase transfer vehicles for the transport of Methyl Orange, an anionic dye molecule, into an organic medium. 

Fatty acids are especially important and ubiquitous lipids. Apart from their use as fuel, they may be used in the synthesis of many other kinds of molecules. A fatty acid is a hydrocarbon chain with a terminal —COOH group. Usually, fatty acids contain between 14 and 25 carbons, 16 and 18 being most common. Unsaturated fatty acids are those that contain double bonds between some carbon atoms. Saturated fatty acids contain only single bonds. Palmitic acid (16) and stearic acid (Cl8) are particularly common saturated fatty acids in humans. Linoleic acid (Cl8), linolenic acid (Cl8) and arachidonic acid (C20) are common polyunsaturated fatty acids ( poly meaning more than one double bond). The number of carbons typically is even, reflecting the fact that fatty acid chains are built up (and broken down) in units of 2 carbon atoms at a time. 

Sample Terminally branched saturates Mono- unsaturates Poly- unsaturates Sat. Branched mono- unsaturates Mid-chain branched saturates Satur- ates Total fatty acid (ng/g organic C)... 

Unsaturated poly(ester-imide) resins are known having imide structures at the end of the molecule or in the backbone. Chain termination by imide is frequently done with the tetrahydrophthalic anhydride (23) aminoethanol (9) reaction product [10,201-204]. In the synthesis of these resins, maleic anhydride is used. It is cheap and a world-wide available raw material, having the advantage of generating per mol only one mol of distillate. Patents are known where fumar-ic acid is claimed, e.g., in [205], but it is probably not frequently used in industrial processes. Anyway, under the conditions of the esterification reaction, a part of the maleate is isomerised into the fumarate [206]. To get materials with good heat resistance the use of THEIC is claimed for branching the unsaturated poly(ester-imide) resins [202]. Flexibility and heat resistance are improved when fatty acids, e.g., castor oil fatty acid [205,207], are build into the macromolecule. 

When using substoichiometric amounts of a fatty acid chloride in the presence of triethylamine with either amine terminated poly(amidoamine) PAMAM or poly(trimethyleneamine) POPAM-type dendrimers one observes only fully unreacted and fully reacted dendrimer products as illustrated in Fig. 7. This observation may be interpreted as a manifestation of regiospecific self-assembly, fol-... 

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