Publication detail

The Effect of Freezing Rate on Properties of PVA Hydrogels Prepared by Cyclic Freezing/Thawing

TRUDIČOVÁ, M. ZAHRÁDKA, J. SEDLÁČEK, P. PEKAŘ, M.

Original Title

Type

abstract

Language

English

Original Abstract

Optical, mechanical, and transport properties of hydrogels are crucial for their potential applications. One of the widely used polymers for preparation of hydrogels for biomedical applications is polyvinyl alcohol (PVA). PVA hydrogels can be formed via physical crosslinking (e.g. by cyclic freezing/thawing of aqueous PVA solutions) or with a chemical cross linker (e.g. glutaraldehyd). Physically crosslinked PVA hydrogels are more suitable candidates for biomedical applications because they do not contain residues of potentially hazardous substances (e.g. crosslinkers and others). Properties of a physically crosslinked PVA hydrogel can be influenced by the concentration of PVA and by the temperature of freezing that defines the freezing rate. This work therefore focuses on the study of changes in the optical and mechanical properties caused by the modification of the preparation process of PVA hydrogels. The microstructure was also observed and the connection between the change in optical and mechanical properties and the change in structure were evaluated. Hydrogels in this work were prepared via cyclic freezing/thawing under different cryogenic conditions (liquid nitrogen, two different laboratory freezers and ice bath) and with different concentrations of polyvinyl alcohol (2.5 to 15 wt. %). Rheology was the main technique to study the mechanical properties of the hydrogels. Optical properties were studied only visually because of the insufficient transparency of some samples. The microstructure of selected samples was observed by scanning electron microscopy after freeze-drying. Results showed that the concentration of polyvinyl alcohol in the hydrogel partially changes the properties of the resulting hydrogel. However, the rate of freezing has the major effect on the properties.

Keywords

hydrogel, polyvinyl alcohol, rheology, scanning electron microscopy

Authors

TRUDIČOVÁ, M.; ZAHRÁDKA, J.; SEDLÁČEK, P.; PEKAŘ, M.

Released

27. 11. 2020

Publisher

Vysoké učení technické v Brně, Fakulta chemická

Location

Brno

ISBN

978-80-214-5920-0

Book

Studentská odborná konference CHEMIE JE ŽIVOT 2020 Sborník abstraktů

Edition number

první

Pages from

146

Pages to

147

Pages count

BibTex

@misc{BUT172881,
  author="Monika {Trudičová} and Jan {Zahrádka} and Petr {Sedláček} and Miloslav {Pekař}",
  title="The Effect of Freezing Rate on Properties of PVA Hydrogels Prepared by Cyclic Freezing/Thawing",
  booktitle="Studentská odborná konference
CHEMIE JE ŽIVOT 2020
Sborník abstraktů",
  year="2020",
  edition="první",
  pages="146--147",
  publisher="Vysoké učení technické v Brně, Fakulta chemická",
  address="Brno",
  isbn="978-80-214-5920-0",
  note="abstract"
}