Synthesis and Properties of Bioresorbable Block Copolymers of l-Lactide, Glycolide, Butyl Succinate and Butyl Citrate

Abstract

The paper presents the course of synthesis and properties of a series of block copolymers intended for biomedical applications, mainly as a material for forming scaffolds for tissue engineering. These materials were obtained in the polymerization of l-lactide and copolymerization of l-lactide with glycolide carried out using a number of macroinitiators previously obtained in the reaction of polytransesterification of succinic diester, citric triester and 1,4-butanediol. NMR, FTIR and DSC were used to characterize the materials obtained; wettability and surface free energy were assessed too. Moreover, biological tests, i.e., viability and metabolic activity of MG-63 osteoblast-like cells in contact with synthesized polymers were performed. Properties of obtained block copolymers were controlled by the composition of the polymerization mixture and by the composition of the macroinitiator. The copolymers contained active side hydroxyl groups derived from citrate units present in the polymer chain. During the polymerization of l-lactide in the presence of polyesters with butylene citrate units in the chain, obtained products of the reaction held a fraction of highly branched copolymers with ultrahigh molecular weight. The reason for this observed phenomenon was strong intermolecular transesterification directed to lactidyl side chains, formed as a result of chain growth on hydroxyl groups related to the quaternary carbons of the citrate units. Based on the physicochemical properties and results of biological tests it was found that the most promising materials for scaffolds formation were poly(l-lactide–co–glycolide)–block–poly(butylene succinate–co–butylene citrate)s, especially those copolymers containing more than 60 mol % of lactidyl units.

Nanomaterials for Biomedical Applications: Production, Characterisations, Recent Trends and Difficulties

“…Non-wetting polymerisation enables adjustment of the shape, size and composition of the fabricated NPs and is capable of large mass production, which is why this method is widely used in the industrial field. Successful production of polymer nanomaterials has been achieved for several polymers, namely common biodegradable polymers such as poly(D,L-lactide-co-glycolide) (PLGA), poly(D,L-glycolide) (PLG), poly(cyanoacrylate) (PCA) and poly(lactic acid) (PLA) [ 74 , 75 , 76 ]. Some physicochemical features that can be used to screen the characteristics of polymeric colloidal suspensions are particle diameter, surface charge, polymer molar mass dissemination, loaded medication and pH.…”

Triple-Shape Memory Behavior of Modified Lactide/Glycolide Copolymers

“…The oligo (butylene succinate) (BS) was synthesized by the transesterification of succinic acid methyl di-ester with 1,4-butanediol, according to the method described detailed previously [ 36 ]. This copolymer presents the linear microstructure of the chain.…”

“…The oligo (butylene citrate) (CA) and oligo (butylene succinate- co -butylene citrate) (BSCA) with a 40/60 molar ratio of derivatives of citric acid to succinic acid were synthesized by the analogous method. In turn, these oligomers, due to the presence of citric acid derivatives, presented a branched chain microstructure with side hydroxyl groups [ 36 ]. The chain structures of used oligoesters are pictured in Scheme 1 .…”

Color Fixation Strategies on Sustainable Poly-Butylene Succinate Using Biobased Itaconic Acid

“…The materials and products derived from bioPBS are soft, flexible and have become a promising replacement for commodities [ 4 ] such as polyethylene terephthalate (PET), polypropylene (PP) and polyethylene (PE) as they exhibit nearly comparable mechanical properties [ 5 ] to these synthetic plastics for several applications such as packaging, construction applications, houseware, furniture or agriculture [ 6 ]. In addition, bioPBS undergoes biodegradation during disposal in compost, moist soil, fresh water and seawater [ 7 ], which reduces its potential environmental impact and makes it a promising candidate to enhance the sustainability of plastic products—as currently demanded by the markets and consumers.…”