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

就就业和净出口而言，纸浆和造纸工业是加拿大最大的制造业。加拿大纸浆和造纸工业一直在世界市场上发挥主导作用。然而，近年来，全球竞争不断加剧。为了应对这一挑战，加拿大纸浆和造纸工业最近确定了一项战略重点，即从机械纸浆中开发增值产品。漂白化学-热力浆（BCTMP）是机械浆等级的主要组成部分。随着纸浆制造、机械纸浆漂白和造纸机械的进步，BCTMP现在可以作为牛皮纸浆的替代品，用于许多高端应用，如涂布无木纸、复写纸、无碳纸和其他特种纸，以及薄纸、毛绒纸浆和多重纸板。BCTMP在各种纸张等级中使用量增加的主要驱动因素不仅是降低成本，而且使用BCTMP获得的纸张体积更大，不透明度更高，可印刷性更好。然而，为了进一步增加BCTMP在无木纸中的使用，需要解决一些技术问题，如表面粗化。此外，电路板制造商对更高的体积有需求，以便在较低的基础重量下获得相同的卡尺。该项目的目的是了解表面粗化和纸块形成的机理，并确定与表面粗化和纸块有关的关键纤维特性。预计该项目将导致纤维表征和纸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-纸关系的新认识。从该项目中获得的知识将直接使加拿大的几家机械纸浆生产商受益，使他们能够修改其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.