Degradation characterization of aliphatic polyesters -In vitro study

• Type: Article in International Conference Proceedings Book
• Date: 2008

Authors

Vieira, AC (Author) Other; Vieira, JC (Author) Other; Guedes, RM (Author) FEUP; Marques, AT (Author) FEUP

Conference proceedings International

Title: IVTH INTERNATIONAL CONFERENCE ON TIMES OF POLYMERS (TOP) AND COMPOSITES

Pages: 309-+

4th International Conference on Times of Polymers TOP and Composites

Ischia, ITALY, SEP 21-24, 2008

Indexing

ISI Web of Knowledge - 2 Citations

Scopus - 3 Citations

Scientific classification

FOS: Engineering and technology > Mechanical engineering

Other information

Authenticus ID: P-004-3RR

DOI: 10.1063/1.2989044

Abstract (EN): The most popular and important biodegradable polymers are aliphatic polyesters, such as polylactic acid (PLA), polyglycolic acid (PGA), polycaprolactone (PCL), polyhydoxyalkanoates (PHA's) and polyethylene oxide (PEO). However, each of these has some shortcomings which restrict its applications. Blending techniques are an extremely promising approach which can improve or tune the original properties of the polymers[l]. Aliphatic polyesters are a central class of biodegradable polymers, because hydrolytic and/or enzymatic chain cleavage of these materials leads to alpha-hydroxyacids, which in most cases are ultimately metabolized in human body. This is particularly useful for controlled release devices and for other biomedical applications like suture fibers and ligaments. For aliphatic polyesters, hydrolysis rates are affected by the temperature, molecular structure, and ester group density as well as by the species of enzyme used. The degree of crystallinity may be a crucial factor, since enzymes attack mainly the amorphous domains of a polymer. Four different aliphatic polyesters were characterized in terms of degradation. Sutures fibers of PGA-PCL, PGA, PLA-PCL and PDO were used in this study. Weight loss, pH, molecular weight, crystallinity and strength were measured after six stages of incubation in distilled water, physiological saline and phosphate buffer solution (PBS). Degradation rate was determined, using a first order kinetic equation for all materials in the three incubation media. A relatively wide range of mechanical properties and degradation rates were observed among the materials studied. PBS was the most aggressive environment for the majority of cases.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 2