Structure, Properties, Degradation, and Applications

Tsuji, H. (2005) Poly(lactide) stereocomplexes Formation, structure, properties, degradation, and applications. Macromolecular Bioscience, 5, 569-597. 

Tsuji H (2005) Poly(lactide) Stereocomplexes Formation, Structure, Properties, Degradation, and Applications. Macromol Biosci 5 569-597... 

Several review articles on biodegradable polymers and polyesters have appeared in the literature [12-22]. Extensive studies have been carried out by Al-bertsson and coworkers developing biodegradable polymers such as polyesters, polyanhydrides, polycarbonates, etc., and relating the structure and properties of aliphatic polyesters prepared by ROP and polycondensation techniques. In the present paper, the current status of aliphatic polyesters and copolyesters (block, random, and star-shaped), their synthesis and characterization, properties, degradation, and applications are described. Emphasis is placed primarily on aliphatic polyesters derived by condensation of diols with dicarboxylic acids (or their derivatives) or by the ROP of cyclic monoesters. Polyesters derived from cyclic diesters or microbial polyesters are beyond the scope of this review. 

Tsuji, H. (2010) Hydrolytic degradation, in Poly(LacticAcid) Synthesis, Structures, Properties Processing, and Applications (Wiley Series on Polymer Engineering and Technology) (eds R. Auras, L.-T. Lim, S.E.M. Selke and H. Tsuji), John Wiley Sons, Inc., NJ, pp. 345-381. 

The first section of this book deals with current topics in network theory directed toward explaining the relationship between molecular architecture and macroscopic physical properties. The closely related questions of network formation and degradation are also discussed in this section. Deformation, fatigue, and fracture are discussed in the second section. The third section includes recent advances in cross-linking chemistry several chapters outline applications of new systems and detail the relationship between network structure and application properties. 

No single polymer can match all of the above criteria. This has led companies to develop application-specific polymers and/or series of polymers that may have the structure property variability to encompass all potential applications. As listed in Table 3, several properties of the polymer have a direct effect on its degradation kinetics and consequently on the drug release profile. Hence novel polymers that... 

However, the long range effectiveness of polymer additives remains, due to the mechanical degradation, a hitherto unsolved problem. By application of the above-mentioned theoretical approaches and the influence of laminar and elongational flow on polymer stability described in Sect. 6.3.4, it seems possible to retain the flow features over a longer period. It is therefore necessary to reinforce investigations which enable a more quantitative description of turbulent flow, so that in the future structure-property relationships can be established which permit a correlation of the microscopic structure of the macromolecules with the observed flow phenomena. 

In polytriacetylenes (Fig. 19) the conjugation across the backbone is weaker than for polyenes. Conversely, the PTAs are stable under normal laboratory condition and show no degradation over months, which makes them an interesting candidate for applications. Furthermore, the chemical synthesis allows to have a well defined number of monomer units and to attach definite functional groups enabling the study of the structure-property relationships in nonlinear optics. 

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