Polyester biomedical applications

Biomedical applications, 27 Bionolle, 28, 42, 43 Biopol polyesters, 28, 41 Bioresorbable polyesters, 27 synthesis of, 99-101 Biphenol-based copolymers, 356 Bis(aryloxy) monomers, polymerization of, 347... 

Gref R, Rodrigues J, Couvreur P (2002) Polysaccharides grafted with polyesters novel amphiphilic copolymers for biomedical applications. Macromolecules 35 9861-9867... 

Bioerodible polymers offer a unique combination of properties that can be tailored to suit nearly any controlled drug delivery application. By far the most common bioerodible polymers employed for biomedical applications are polyesters and polyethers (e.g., polyethylene glycol), polylactide, polyglycolide and their copolymers). These polymers are biocompatible, have good mechanical properties, and have been used in... 

This review aims at reporting on the synthesis of aliphatic polyesters by ROP of lactones. It is worth noting that lactones include cyclic mono- and diesters. Typical cyclic diesters are lactide and glycolide, whose polymerizations provide aliphatic polyesters widely used in the frame of biomedical applications. Nevertheless, this review will focus on the polymerization of cyclic monoesters. It will be shown that the ROP of lactones can take place by various mechanisms. The polymerization can be initiated by anions, organometallic species, cations, and nucleophiles. It can also be catalyzed by Bronsted acids, Lewis acids, enzymes, organic nucleophiles, and bases. The number of processes reported for the ROP of lactones is so huge that it is almost impossible to describe aU of them. In this review, we will focus on the more... 

Malberg S, Plikk P, Fiime-Wistrand A, Albertsson A-C (2010) Design of elastomeric homo-and copolymer networks of functional aliphatic polyester for use in biomedical applications. Chem Mater 22 3009-3014... 

From the results presented in this chapter we can conclude that it is feasible to prepare sugar-based polymers analogous to the more qualified technological polymers - polyamides, polyesters, polyurethanes - with an enhanced hydrophilicity and degradability. However, in most cases, the high costs associated with the preparation of the monomers restrict the application of these polymers to biomedical applications and other specialized fields. More readily available monomers and simpler polymerization processes have to be found if sugar-derived polymers should compete with petrochemical-based polymers that are used in domestic applications. 

Aliphatic polyesters have received great interest for potential biomedical application. Polythioesters (polyesters in which one of the oxygen atoms of the ester groups has been replaced by a sulfur atom) have received less attention, although these materials are expected to show interesting material properties such as higher... 

Enzymes that belong to the class of hydrolases are by far the most frequently-applied enzymes in polymer chemistry and are discussed in Chaps. 3-6. Although hydrolases typically catalyse hydrolysis reactions, in synthetic conditions they have also been used as catalysts for the reverse reaction, i.e. the bond-forming reaction. In particular, lipases emerged as stable and versatile catalysts in water-poor media and have been applied to prepare polyesters, polyamides and polycarbonates, all polymers with great potential in a variety of biomedical applications. 

These features of these materials spurred the scientific community to utilize them in biomedical applications [49]. In particular, the synergy between their multivalency and size on the nanoscale enables a chemical smartness along their molecular scaffold that achieves environmentally sensitive modalities. These functional materials are expected to revolutionize the existing therapeutic practice. Dendritic molecules, such as polyamidoamine, polylysine, polyester, polyglycerol (PG), and triazine dendrimers, have been introduced for biomedical applications to amplify or multiply molecularly pathopharmacological effects [73]. 

Aliphatic polyesters are an attractive class of polymer that can be used in biomedical and pharmaceutical applications. One reason for the growing interest in this type of degradable polymer is that their physical and chemical properties can be varied over a wide range by, e.g., copolymerization and advanced macro-molecular architecture. The synthesis of novel polymer structures through ringopening polymerization has been studied for a number of years [1-5]. The development of macromolecules with strictly defined structures and properties, aimed at biomedical applications, leads to complex and advanced architecture and a diversification of the hydrolyzable polymers. 

Seppala, J. V.,Helminen, A. O., and Korhonen, H. (2004), Degradable polyesters through chain linking for packaging and biomedical applications, Macromol. Biosci., 4(3), 208-217. 

Fatty acid based biodegradable polymers have many biomedical applications. This short review focuses on controlled drug delivery using two classes of the polymers polyanhydrides and polyesters based on fatty acids as drug carriers. Different polymer types and compositions are summarized showing the potential of these polymers as drug carriers. 

Specialty polymers achieve very high performance and find limited but critical use in aerospace composites, in electronic industries, as membranes for gas and liquid separations, as fire-retardant textile fabrics for firefighters and race-car drivers, and for biomedical applications (as sutures and surgical implants). The most important class of specialty plastics is polyimides. Other specialty polymers include polyetherimide, poly(amide-imide), polybismaleimides, ionic polymers, polyphosphazenes, poly(aryl ether ketones), polyarylates and related aromatic polyesters, and ultrahigh-molecular-weight polyethylene (Fig. 14.9). 

A recent study has shown that membranes made of a modified polyetheretherketone (PEEK-WC) are interesting materials for biomedical applications [23,24]. The cytocompatibility of PEEK-WC membranes was evaluated by culturing hepatocytes isolated from rat liver (Figure 43.6). The properties of PEEK-WC membranes were compared to polyurethane membranes prepared using the same technique, and commercial membranes (made of Nylon, polyethersulphone, and polyester). The results have shown that PEEK-WC membranes promoted hepatocyte adhesion most effectively and metabolic activities of cells cultured on these membranes improved significantly. 

A wide variety of chemical catalysts is nowadays available to polymerize monomers into well-defined polymers and polymer architectures that are applicable in advanced materials for example, as biomedical applications and nanotechnology. However, synthetic polymers rarely possess well-defined stereochemistries in their backbones. This sharply contrasts with the polymers made by nature where perfect stereocontrol is the norm. An interesting exception is poly-L-lactide, a polyester that is used in a variety of biomedical applications [1]. By simply playing with the stereochemistry of the backbone, properties ranging from a semicrystalline, high melting polymer (poly-L-lactide) to an amorphous high Tg polymer (poly-meso-lactide) have been achieved [2]. 

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