Fogorvosi szemle, 2007 (100. évfolyam, 1-6. szám)

2007-02-01 / 1. szám

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FOGORVOSI SZEMLE ■ 100. évf. 1. sz. 2007.

hatására bennük nagyobb, gyakran repedéshez, töréshez vezető feszültség keletkezik. Eredményeink alapján megállapíthatjuk, hogy a fotopolimerizációval előállított hidrogélek térhálósűrűsége jellemzően meghatározza a nyomószilárdságot és az ezzel összefüggésben lévő fizikai paramétereket (pl.: nyomási, illetve rugalmassági modulus), vagyis az összetevők változtatásával befolyásolható fizikai paraméterekkel rendelkező anyagot hoztunk létre.

Köszönetnyilvánítás

A kutatás a RET (Regionális Egyetemi Tudásközpont) kapcsolódási szám (RET-06/432/2004) és (RET-06/ 423/2004) támogatásával valósult meg. Köszönettel tartozunk még Rózsáné Lukács Júlia méréseinkben nyújtott segítségéért. (Alkalmazott Kémiai Tanszék, Dr. Zsuga Miklós tanszékvezető egyetemi tanár, Dr. Deák György tudományos munkatárs)

Irodalom

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12. Nuno-Donlucas SM, Sàncez-Dîaz JC, Rabelero M, Cortés-Ortega J, Lurhs-Olmos CC, Fernández-Escamilla VV, Mendizábal E, Puig JE: Microstructured polyacrylamide hydrogels made with hydrophobic nanoparticles. J Colloid Interface Sei 2004; 270(1 ): 94-98.

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Dr. Szepesi M, Bakó J, Márton S, Dr. Borbély J, Dr. Hegedűs Cs:

Synthesis and compression strength of hydrogels

The purpose of the present investigation was the synthesis of crosslinked polymers and the assay of the effect of the monomer ratio to the compression values. Hydrogels were made by free radical photoinitiation from 2-hydroxyethyl metachrylate (HEMA) monomer, polyethylene glycol) dimethacrylate (PEG-DMA) crosslinker and sodium anthraquinone-2-sulphonate initiation The concentration of HEMA and PEG-DMA was 30 %, and their ratio was varied to obtain gels with different crosslinking density.

It was found, that increasing the amount of the crosslinker in the gels, the force of the deformation increased, however the elasticity decreased. The lowest difference was found between the molar ratio of 50% HEMA: 50% PEG-DMA and the 75% HEMA: 25% PEG-DMA gels. Compression strength was strongly influenced on the ratio of the crosslinking agent. The smallest compression strength was found at the lowest amount of PEG-DMA (90% HEMA: 10% PEGDMA) (0.0475 MPa ± 0.0117) and the highest value was found at the highest amount of the PEG-DMA (10% HEMA: 90% PEG-DMA) (0.1366 MPa ± 0.0546). The values of the compression strength at gels with similar composition was not significantly different.

On the base of the present investigations the elasticity of the materials could be calculated from the ratio of monomers. It could be an important parameter in the further applications of the gels as a local delivery system in the parodontology.

Key words: hydrogel, compression strength, Young-modulus