MECHANICAL PULP CHARACTERIZATION - A NEW AND RAPID METHOD TO EVALUATEFIBER FLEXIBILITY

A new method of measuring the flexibility of high-yield pulp fibres wa s developed in order to characterize two different types of mechanical pulp: CTMP and TMP. This method is based on the Bauer McNett classifi cation and the average fibre lengths obtained with a Kajaani FS100 app aratus. The determination of the average fibre length of each fraction from the Bauer McNett classifier and the correlation between the Kaja ani lengths and the theoretical McNett lengths allows a dynamic and a static flexibility coefficient to be defined. This flexibility measure ment is applicable to all sorts of lignocellulosic fibres. Flexibility coefficients are affected by refining, bleaching, the wood species an d the mechanical pulping process. Flexibility is an important paramete r in the development of the optical characteristics and strengths of t he pulps. This method is rapid and can be used for laboratory control purposes in pulp production. It is one way to characterize high-yield pulp fibres and to better understand the way the fibre evolves during the production process.