Amphiphilic Polyesters Derived from Silylated and Germylated Fatty Compounds

Abstract

New classes of amphiphilic polyesters were prepared from metallated (Si, Ge) fatty methyl ester (FAME) precursors and poly(tetramethylene oxide) glycol. Hydrosilylation of 10-undecenoic methyl ester by tetramethyldisiloxane occurred at 80 degrees C in the presence of Karstedt's catalyst, and hydrogermylation of the same FAME derivative was obtained at the same temperature under radical AIBN initiation. These diester precursors, obtained in high yields (approximately 90%), reacted with poly(tetramethylene oxide) glycol under free solvent to give silicon polymers or germanium oligomers. These condensed materials display both the characteristic of organic-inorganic hybrid materials and those of amphiphilic polymers. The nature of organometallic fragment (hydrophobicity of tetramethyldisiloxy and sterical hindrance of diphenylgermyl) was shown to influence the chemical reactivity of the polymerizable monomers and the physical properties of the resulting copolymers. The amphiphilicity of these materials provides a driving force for the formation of small objects (approximately 1 nm), making them very attractive as hybrid nanocontainers.

Branched Polyesters From Germylated and Fatty Compounds

“…Consequently, they are storable and easy to handle. The equivalent linear polyester 16 exhibited very satisfactory solubility in common organic solvents, whereas the new polyesters 1, 2, 3 and 4 are quite insoluble in the same classic organic solvents due to their polydimensional structure.…”

“…Some of the more promising polymeric substances are those obtained from fatty acids, which are biocompatible, cost effective, and biodegradable [5][6][7][8][9][10][11][12] . The specific usefulness of fatty acids is determined by the presence of carbon-carbon double bonds and acid functions, susceptible to cationic, radical polymerizations or polyesterification reactions [13][14][15][16] . All these reactions open up new vistas to chemists.…”

“…French workers have made a significant contribution in the area of silylated and germylated fatty compounds [17][18] . These compounds should represent a growing field of research as they offer a wide range of interesting properties and applications observed in many organometallic polymers 16,[19][20][21][22][23][24][25][26][27][28] . The structural investigations indicate that silicon or germanium based-polymers can exist with various skeletal structures such as linear, branched or cross-linked polymers.…”

“…Although branched polymers exhibit usually very low solubility in classical solvents, the interest in these kinds of materials is growing intensively because the macromolecular organization can allow the formation of interesting cavities needed for specific applications as in catalysis, as additives or as new film materials [29][30][31][32][33][34][35][36] . Recently, we reported on the synthesis and characterization of fatty methyl di-ester (FAME) containing silicon and germanium elements via catalyzedhydrosilylation and hydrogermylation reactions 16 . The new class of metallated fatty methyl diesters was used as monomers in polymerization reactions of polytransesterification with poly(tetramethylene oxide) glycol of different molecular weights.…”

“…Linear organometallic polyesters were obtained and characterized successfully. The physical study of these condensed materials showed that they are amphiphilic and they adopt a nano container structure, which could lead to very interesting applications in various fields of chemistry, especially in drug delivery and release of bio-active molecules 16 . These reactions can also be adapted to the synthesis of branched organometallic polyesters by varying either one or both of the monomers containing at least three functionalities.…”