Biobased Hyperbranched Poly(ester)s of Precise Structure for the Release of Therapeutics

Abstract

Hyperbrached poly(ester)s derived from naturally-occurring biomonomers may serve as excellent platforms for the sustained-release of therapeutics. Those generated from glycerol are particularly attractive. Traditionally, the difference in reactivity of the hydroxyl groups of glycerol has precluded the formation of well-defined polymers at high monomer conversion without gelation. Using the Martin-Smith model to select appropriate monomer ratios (ratios of functional groups), polymerization may be carried out to high conversion while avoiding gelation and with the assurance of a single type of endgroup. Various agents may be attached via esterification, amide formation or other process. Sustained release of the active agent may be readily achieved by enzyme-catalyzed hydrolysis.

Biobased Glycerol Hyperbranched Poly(Ester)s of Precise Structure as Plasticizers for Poly (Vinyl Chloride)

“…Empirical methods do not permit polymerization to a high degree of monomer conversion without gelation or the targeting of molecular weight, degree of branching or endpoint identity based on initial reactant stoichiometry. A more rational approach is required [40][41][42][43]. Using the Martin-Smith model for the determination of initial monomer ratios (ratio of reactive functional groups), polymerization may be carried out of high degrees of monomer conversion without gelation.…”

Thermal Degradation of Organophosphorus Flame Retardants

“…Nuclear magnetic resonance (NMR) spectra were obtained using a Varian Mercury 300 MH z spectrometer and approximately 10% solutions in deuterochloroform. 1 H and 13 C chemical shifts are reported in parts-per-million (δ) with respect to the resonance for tetramethylsilane (TMS) as internal reference (δ = 0.00); 31 P chemical shifts with respect to the resonance for triphenyl phosphate (δ = −18.00) as internal reference.…”

“…Oligomeric flame retardants offer the advantage of reduced migration over small molecule counterparts. Recently developed techniques permit the ready synthesis of hyperbranched poly(ester)s of precise structure from the abundantly available biomonomers, glycerol and adipic acid [31][32][33]. Using the Martin-Smith model for the determination of initial monomer ratios, polymerization may be carried out to high degrees of monomer conversion without gelation.…”