In vitro adhesion measurements of plasticized oligoesters

Lenka veselá Diploma theses 2008 There are summarized the basic theories and mechanisms of bioadhesion, the factors influencing bioadhesion, the bioadhesive polymers and the most common methods of bioadhesive testing in vitro in the theoretic part of this thesis. There were measured the dynamic viscosity of plasticized polymers of D, L- lactic and glykolic acid branched with mannitol (M) or dipentaerythritol (D) in the concentration of 3%, 5% and 8% in the experimental part of this thesis. Like plasticizer there was used methylester of salicylic acid (MS) in the concentration of 10 - 50%. The dynamic viscosity was measured on the digital viscometer Brookfield DV-E with the adapter for small volume of samples and there was used the spindle No.15. The samples were heated up 40řC. There was found, that applies by all tested plasticized carriers with different type and concentration of branching component, that the viscosity falls with increasing concentration of plasticizer. The viscosity falls by one rank with increasing concentration of plasticizer by 10%. The viscosity of branched polymers is also influenced by the molecular weight and the degree of branching. There was found, that oligoesters with higher molecular weight and with lower degree of branching have higher viscosity. If there is the..