|
|
Study on relaxation properties of hydrogels using rheological techniques
Lorenc, Pavel ; Klučáková, Martina (referee) ; Smilek, Jiří (advisor)
Submitted bachelor’s thesis deals with the study of relaxation and time stress of viscoelastic substances (hydrogels) using selected rheological techniques, especially with regard to oscillation tests. Hydrogels with different types of crosslinking were prepared and their properties were compared during the measurement. Agarose hydrogels (physically), alginate hydrogels (physicochemically), polyvinyl alcohol hydrogels (chemically) and hyaluronic acid hydrogels (ionically). In this bachelor's thesis, methods for measuring the relaxation properties of these hydrogels using a rheometer were designed and subsequently applied. We examined the relaxation properties of hydrogels using time-dependent tests that examined changes in amplitude over time. We performed a test that had 3 intervals, in which we monitored the response of hydrogels to the changes by changing the amplitudes of deformation with time. The relaxation properties of these hydrogels were studied, which showed significant differences in the behavior of hydrogels in measurements.By these methods, it was found that the structure of hydrogels and concentrations have an influence on relaxation. From the measured results, it was shown that the best relaxing properties have chemically crosslinked polyvinyl alcohol hydrogel, the lowest ability to relax was shown by physico-chemically crosslinked alginate hydrogel.The results from the measured data were finally compared, assessed and commented on the differences between the individual hydrogels.
|
|
|
Study on relaxation properties of hydrogels using rheological techniques
Lorenc, Pavel ; Klučáková, Martina (referee) ; Smilek, Jiří (advisor)
Submitted bachelor’s thesis deals with the study of relaxation and time stress of viscoelastic substances (hydrogels) using selected rheological techniques, especially with regard to oscillation tests. Hydrogels with different types of crosslinking were prepared and their properties were compared during the measurement. Agarose hydrogels (physically), alginate hydrogels (physicochemically), polyvinyl alcohol hydrogels (chemically) and hyaluronic acid hydrogels (ionically). In this bachelor's thesis, methods for measuring the relaxation properties of these hydrogels using a rheometer were designed and subsequently applied. We examined the relaxation properties of hydrogels using time-dependent tests that examined changes in amplitude over time. We performed a test that had 3 intervals, in which we monitored the response of hydrogels to the changes by changing the amplitudes of deformation with time. The relaxation properties of these hydrogels were studied, which showed significant differences in the behavior of hydrogels in measurements.By these methods, it was found that the structure of hydrogels and concentrations have an influence on relaxation. From the measured results, it was shown that the best relaxing properties have chemically crosslinked polyvinyl alcohol hydrogel, the lowest ability to relax was shown by physico-chemically crosslinked alginate hydrogel.The results from the measured data were finally compared, assessed and commented on the differences between the individual hydrogels.
|
guest ::
RSS feed.