title: [The use of contact angle and the surface free energy as the surface characteristics of the polymers used in medicine].
abstract: BACKGROUND
  In the interaction process between implant and a living organism an important role is covered by the material layer. Many studies in the field of chemical engineering concern biomaterials surface.
  
  
  OBJECTIVE
  Changes estimation of properties of polymers surface layer due to hydrolytic degradation on the base on measurements of contact angles and calculation of the surface free energy.
  
  
  METHODS
  Contact angle measurements were made for the two polymers: polylactide (PLA) and polyhydroxyalkanoate (PHA) undergoing the hydrolytic degradation process over a period of 27 months. Based on the measured values of contact angles, surface free energy by the Owens-Wendt method and the critical surface tension were calculated.
  
  
  RESULTS
  The surface for both tested polymers is hydrophilic. Hydrolytic degradation influences the growth of the surface free energy and the critical surface tension.
  
  
  CONCLUSIONS
  Methodology can be a easily available for the initial assessment of the material from the point of view of the ability to cell adhesion and the progress of the degradation process.
authors.affiliation: Zakład Mechaniki Doświadczalnej i Biomechaniki, Instytut Mechaniki Stosowanej, Wydział Mechaniczny, Politechnika Krakowska, Kraków, Polska.
authors.forename: Aneta
authors.initials: A
authors.lastname: Liber-Kneć
authors.affiliation: Zakład Mechaniki Doświadczalnej i Biomechaniki, Instytut Mechaniki Stosowanej, Wydział Mechaniczny, Politechnika Krakowska, Kraków, Polska.
authors.forename: Sylwia
authors.initials: S
authors.lastname: Łagan
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D019544:Equipment Failure Analysis; D057927:Hydrophobic and Hydrophilic Interactions; D011091:Polyesters; D011108:Polymers / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D011091:Polyesters; D011108:Polymers; C033616:poly(lactide)