Paraffin Wax Emulsion as Water Repellent for Cotton/Polyester Blended Fabric

Paraffin wax emulsion is prepared by emulsifying paraffin wax (PW) in water using stearic acid (SA) and triethanolamine (TEA) emulsifying system. A mother emulsion is prepared at different concentrations of PW (10.5—19.1%w/w) and SA (4.5—13%w/w) neutralized to different extents by TEA (25—100% degree of neutralization). Upon treating 50/50 cotton/polyester fabric with a padding solution containing 50 g/L of different mother emulsions, its water repellency does not exceed the value of 50. Aluminum chloride proves to be the best deactivating agent of the hydrophilicity of the emulsifying agent among other salts including barium chloride, zinc sulfate, and aluminum sulfate. Optimum emulsion ingredients are found to be PW (10.5%w/w), SA (4.5% w/w), TEA (2.4% w/w, to attain full neutralization of SA), and SA/AlCl ₃ molar ratio (1/1). Treating the fabric with the deactivated emulsion results in enhancing its water repellency rating (up to 80), decreasing its surface roughness, and increasing its stiffness. A scanning electron micrograph of the treated fabric shows the deposition of the emulsified wax on the fabric surface. Treating the fabric with the emulsion in the presence of a fluorochemical finish, namely Nuva FB of Clariant, proves that the first can be used as an extender for the second. Raising the drying temperature to 160 ^· C gives rise to a water-repellency rating of 100.