Parameters affecting formation have been elucidated using a Fourdrinier pilot paper machine and a CPAM/bentonite retention aid system. Two main parameters affecting formation are found to be the contact number between fibres and the bridging strength at the contacts, which influence the fibre floc strength. The bridging strength model, which was developed based on interactions between a single fibre and neighbouring fibres in a floc, taking into account the surface coverage of retention aids on the fibre surface, explains well the effect of retention aids on floc strength and formation. Fillers in the wet-end weaken the fibre floc by transferring polymer from fibre to filler surfaces. The contact number between fibres can be expressed in terms of the crowding number, which is affected by fibre concentration and fibre dimensions.
|Number of pages||8|
|Publication status||Published - 20 Nov 2003|
|Event||5th International Paper and Coating Chemistry Symposium 2003 - Montreal, Canada|
Duration: 16 Jun 2003 → 19 Jun 2003
|Conference||5th International Paper and Coating Chemistry Symposium 2003|
|Period||16/06/03 → 19/06/03|