In this project, spheroidal copper powder 14-25 mu m is mixed with polydimethylsiloxane (PDMS) in a range from 5 to 33 % vol. Three physical properties are examined; hydrophobicity, glass transition temperature (Tg) and electrical conductivity. In the latter, we are specifically looking for the appearance of the percolation threshold which impacts conductivity greatly over a small change in Cu concentration. The PDMS used is Sylgard 184 from Dow Corning, an industrial mix of different PDMS, which is frequently studied in publications. The apparatus used are RUC/homemade, designed mainly for the study of liquids but should still work for the rubber polymer. The percolation threshold was found between 15% and 16% vol., Tg around 150 K and hydrophobicity went from a contact angle of 109° for pure PDMS with little change until 15% vol. then a steeper decrease down to 94° for 33% vol.
|Uddannelser||Fysik, (Bachelor/kandidatuddannelse) Bachelor el. kandidat|
|Udgivelsesdato||22 jun. 2015|
- Glass transition
- dielectric spectroscopy
- Hydrofobic effect