The objective of this project was to help Forintek members to improve MDF manufacturing processes and maintain cost competitiveness by evaluating the existing MDF blending technologies and developing improved or new methods for MDF blending.
MDF blending is a process of transforming a state of having fibre and resin as two separate physical identities into a state of having a “homogeneous” mixture of fibre and resin. Therefore, the author believes that an ideal blending technology should produce resin distribution uniformity very close to being “homogeneous” and retain all the resin mass within the fibres in a reactive state. Best resin droplet size and surface area coverage should be obtained as a result of very uniform resin distribution. On the other hand, it is impossible to obtain optimal resin droplet size and surface area coverage when the mixing of fibre and resin is not uniform. Two subjects are key to the efficiency of MDF blending – resin distribution uniformity and loss of resin. The former is about how well the blending process breaks up the resin into small droplets and distributes them on the fibres. The latter is about the effects of blending conditions on the loss of resin mass such as evaporation of resin light components in the tube dryer or the loss of resin reactivity such as resin pre-cure at elevated temperatures. Based on these considerations and his best interpretations of experimental data and observations, different blending methods were evaluated by the author.