4) Conclusion

The viscosity of two glycerol-water solutions was found using dynamic light scattering and analysis of the auto-correlation function of the intensity of scattered light. For 16% by volume glycerol in water solution, the measured viscosity was 2.14 ± 0.02 mPa.s when measured with 90 nm spheres and 1.85±0.02 mPa.s when measured with 304 nm spheres. The expected value was 1.62 ± 0.06 mPa.s. For 38% by volume glycerol in water solution, the measured viscosity was 4.60 ± 0.05 mPa.s when measured with 90 nm spheres and 3.17±0.01 mPa.s when measured with 304 nm spheres. The expected value was 4.07 ± 0.20 mPa.s. There was a fair amount of background noise that appears to have significantly affected the measurements. With some more time, it is likely that more steps to reduce noise or to eliminate it during analysis could have been taken and the result would be more accurate.