Carbohydrate-Based Copolymers. Synthesis and Characterization of Copoly(ester amide)s Containing l-Arabinose Units

Abstract

Copoly(ester amide)s, abbreviated as PVGAn, have been prepared by random copolymerization of 1-amino-1-deoxy-2,3,4-tri-O-methyl-5-O-[(pentachlorophenoxy)succinyl]-l-arabinitol hydrochloride and 5-amino-1-O-[(pentachlorophenoxy)glutaryl]pentanol hydrochloride by the active ester polycondensation method. The molar ratios of the two comonomers in the feed varied from 1/99 to 50/50. The two monomeric units are randomly distributed within the copolymers, as assessed by NMR analysis, and the degree of randomness and average sequence lengths of the different copoly(ester amide)s have been experimentally determined. Thermal properties depend on the copoly(ester amide) composition, since it was found that the melting and the decomposition temperatures decreased as the molar fraction of carbohydrate-based monomer unit increased, whereas the glass-transition temperature increased in parallel.

Poly(ester amide)s: recent insights into synthesis, stability and biomedical applications

“…3A). 70 For those, the degradation rate could be enhanced by increasing the amount of the sugarbased monomer. Biodegradable PEAs from tartartic acid have also been investigated (M > 80 000), which showed T m and T g values ranging from 100 to 230 and 50 to 100 °C, respectively (Fig.…”

Degradable Poly(ester amide)s for Biomedical Applications

“…PEAs containing succinic acid units degraded faster according to a postulated mechanism where succinimide rings were formed [80]. Random copolymers were also prepared from appropriate mixtures of the above indicated arabinose-succinyl monomers and 5-amino-1-O-[(pentachlorophenoxy)glutaryl]pentanol hydrochloride ( Figure 20) and their hydrolytic degradation studied [81]. Results demonstrated that the degradation rate could be enhanced by increasing the amount of the sugar-based monomer incorporated in the polymer chain.…”

Carbohydrate-Based Copolymers. Hydrolysis of Copoly(ester amide)s Containing l-Arabinose Units

“…Aliphatic poly(ester amide) PVG,10b containing five-carbon diacid units along the backbone, showed, as expected, a low degradation rate . Taking this poly(ester amide) as an example, and with the aim of modulating its rate of hydrolysis, we prepared a series of copoly(ester amide)s, referred to as PVGA n , by copolymerization of 1-amino-1-deoxy-2,3,4-tri- O -methyl-5- O -[(pentachlorophenoxy)succinyl]- l -arabinitol hydrochloride ( 1 ) and 5-amino-1- O -[(pentachlorophenoxy)glutaryl]pentanol hydrochloride ( 2 ) via the active ester polycondensation method (Scheme ). The structure of these copolymers combines the presence of a carbohydrate monomer, which might favor high degradability, with a microstructure designed so that the mechanism of degradation by cyclization to imides could operate.…”

“…Copolymerizations . Copoly(ester amide)s were synthesized by the active ester polycondensation method …”