Characterization and modification of chemi-thermomechanical pulp fibres for custom-made pulp properties

制浆造纸业是加拿大就业人数和净出口量最大的制造业。但加拿大制浆造纸业在世界市场上一直处于领先地位。然而，近年来，全球竞争日益激烈。为了迎接挑战，加拿大制浆造纸业最近确定了发展机械浆附加值产品的战略重点。漂白化学热机械浆(BCTMP)是机械浆品种的主要组成部分。随着纸浆制造、机械浆漂白和造纸机械的进步，BCTMP现在可以在许多高端应用中用作硫酸盐纸浆的替代品，如涂布无木材纸种、复印纸、无碳纸和其他特种纸种，以及卫生纸、绒毛浆和多层纸板。BCTMP在各种纸种中增加使用背后的主要驱动因素不仅是成本的降低，而且使用BCTMP获得的纸张具有更高的体积、更高的不透明度和更好的印刷性能。然而，为了进一步增加BCTMP在无木材纸张中的使用量，需要解决一些技术问题，如表面粗糙化。此外，纸板制造商需要更高的体积，以便以较低的定量获得相同的卡尺。该项目的目的是了解表面粗化的机理和纸团的形成，并确定与表面粗化和纸团有关的关键纤维特性。预计该项目将导致纤维表征和纸张结构分析的新方法的发展，并将导致对机械制浆技术和纤维-纸张关系的新理解。从这个项目中获得的知识将使加拿大的几家机械纸浆生产商直接受益，使他们能够改进他们的工艺技术，以提高纸浆质量。

The pulp and paper industry is the largest manufacturing industry in terms of employment and net exports in Canada.  The Canadian pulp and paper industry has been playing a leading role in the world market.  However, in the recent years, global competition has been increasing.  To meet the challenge, the Canadian pulp and paper industry has recently defined a strategic focus on the development of value-added products from mechanical pulps.  Bleached Chemi-Thermomechanical Pulp (BCTMP) is a major component of the mechanical pulp grades.  With the advances in pulp manufacturing, mechanical pulp bleaching and papermaking machinery, BCTMP can now be used as a substitute for kraft pulp in many high end applications, such as coated wood-free paper grades, copy paper, carbonless paper, and other specialty paper grades, and tissue paper, fluff pulps and multiply boards.  The main drive behind the increased use of BCTMP in various paper grades is not only the cost reduction but also the higher bulk, higher opacity and better printability of paper obtained with the use of BCTMP.   However, some technical issues such as surface roughening need to be addressed in order to further increase the use of BCTMP in wood-free paper.  Also, there is a demand for higher bulk from board manufacturers so that the same caliper can be obtained at a lower basis weight.  The aim of this project is to gain knowledge on the mechanism of surface roughening and the formation of paper bulk, and identify key fibre characteristics with regards to surface roughening and paper bulk.  It is expected that the project will result in the development of novel methodologies for fibre characterization and paper structure analysis and will lead to new understanding of the mechanical pulping technologies and fibre-paper relationship. Knowledge gained from this project will directly benefit several mechanical pulp producers in Canada by enabling them to modify their process technologies for improved pulp quality.