Abstract:
This experimental research is to study the water permeability of porous natural rubber membrane. The membrane is produced by adding o-xylene dispersion stabilized in PVA solution into the pre-vulcanized natural rubber latex and membrane formed by dipping technique. When o-xylene droplets evaporated during vulcanization, holes are formed thus resulting in a breathable membrane. The experiment consists of two parts. In the first part, the correlations of o-xylene drop size and operating parameters, i.e. impeller speed, disperse phase volume fraction and interfacial tension were developed to predict the size and distribution of droplets. เท the second part, the porous natural rubber film was prepared from pre-determined o-xylene dispersion and the latex compound. The PVA stabilizer used is hydrophilic which will facilitate water absorption by the membrane. The experimental result shows that the correlation for predicting drop size diameter can be represented by: D32/Di = 0.02(1+0.89 Ø)W1e-0.6 Where D32 is sauter mean diameter, Di is impeller diameter, Ø is volume fraction and Wei is weber number. It is observed that the permeability decreases with higher impeller speeds due to small drops resulting in small holes in the membrane. In addition, the thicker the membrane the less permeability. Besides, the permeation increases with both temperature and volume fraction.