Dynamic Contact Angle of Modified Biopolymer Droplet on Urea Surface: Temperature Effects

Abstract:

The droplet impact behaviour provides the particle coating characterization during the coating process of controlled release fertiliser. To have a good coating uniformity around the urea granules, it is necessary to enhance the wettabitily properties between the coating material and urea surface. The biopolymer material is preferred as the coating material because this polymer may degrade and will not cause any environmental impact to the environment. Various compositions of starch/urea /borate/lignin were prepared and evaluated for the wettability properties. The wettability characteristic measured is the dynamic contact angle. The high speed Charged-Couple Device (CCD) camera was used to capture the images of this droplet impact behaviour. Temperature plays an important factor during wetting stage because the coating material must be completely dried in continuous coating process in fluidised bed. From this analysis, it indicates that a composition of starch/urea/ borate (50/15/2.5) with 10% lignin has the best wettability characteristic and thus suitable to be used as a coating material. The ideal temperature for the coating process is 60°C.

• Periodical: Key Engineering Materials (Volumes 594-595)
• Pages: 566-570
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.594-595.566
• Online since: December 2013
• Authors: Yon Norasyikin Samsudin, Ku Zilati Ku Shaari, Zakaria Man, Suriati Sufian
• Keywords: Biopolymer, Droplet Spreading, Dynamic Contact Angle, Temperature, Urea Surface

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