Graduation Date

Spring 5-7-2016

Document Type


Degree Name

Master of Science (MS)


Medical Sciences Interdepartmental Area

First Advisor

Dr. Mark Beatty


Introduction: Color changes, physical degradation and fungal infections are potential challenges to the longevity of polydimethylsiloxane (PDMS) elastomers. The purpose of this study was to evaluate potential improvements in color change, physical properties and anti fungal properties of PDMS loaded with TiO2 and ZrO2 nanoparticles.

Methods: 1% weight of 40 nm or 200 nm diameter TiO2 or ZrO2 nanoparticles were mixed into PDMS with 2% functional intrinsic yellow pigment and polymerized. Control materials contained 13% weight 200 nm silica. Samples were exposed to either 3000 hours of UVB radiation (200 μW/cm2) or darkness. Color parameters L*a*b* and ΔE*, ultimate tensile strength, strain, elastic modulus and shore A hardness were measured. Data were analyzed using a factorial ANOVA with Tukey-Kramer post hoc test (p

Results: TiO2 200 nm showed the least color change after 3000 hours of UVB weathering, followed by TiO2 30-40 nm (p

Conclusion: 40 nm and 200 nm TiO2 nanoparticles, when added to pigmented PDMS at 1% weight, provide improved color stability and lower C. albicans growth compared to silica- and zirconia-filled elastomers.