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This paper presents a simulation tool applied to latex film formation by drying, a hybrid between a classical numerical resolution method using finite differences and cellular automata, and making use of object-oriented programming. It consists of dividing real space into cells and applying local physical laws to simulate the exchange of matter between neighboring cells. In a first step, the simulation was applied to the simple case of vertical drying of a latex containing only one population of monodisperse particles and water. Our results show how the distribution of latex particles evolves through the different drying stages due to a combination of diffusion, convection, and particle deformation. While repulsive interactions between the particles tend to favor homogeneous distributions in the first drying stage, concentration gradients that develop in opposite ways can be observed depending on the drying regime. The distributions, calculated in various cases, reproduce and extend several theoretical results and are in qualitative agreement with some experimental findings.

Properties of the flame retardant urea formaldehyde (UF) board made from saw dust fibers were investigated. Flame retardant chemicals that were evaluated include boric acid (BA) and borax (BX) which were incorporated with saw dust fibers to manufacture experimental panels. Three concentration levels, (0.5, 1, and 5%) of fire retardants and 10% urea formaldehyde resin based on oven dry fiber weight were used to manufacture experimental panels. Physical and mechanical properties including water absorption, modulus of rupture (MOR), and modulus of elasticity (MOE) were determined. The results showed that water absorption and bending strength decreased as the flame retardant increased. The highest concentration of (BA + BX) enhanced the fire retardant more than the lower ones. Scanning electron microscope and FTIR of composite panels were studied.