Flax shives refining, chemical modification and hydrophobisation for paper production

The potential use of flax (Linum usitatissimum) shives as a fibre resource for papermaking has been explored by chemically modifying them in situ in the refiner. Flax shives were refined and were reacted with a reaction product of polyols and organic anhydrides, Fibre mats were made with treated fibres after the alkyl ester reaction process. Mechanical properties and refining parameters were compared with conventional wood-based mechanical pulp. Bulk surfaces as well as morphological properties of the fibre components in handsheets were analysed by ESCA, solid-state C-13-NMR, and Fourier transform infrared. Plasticisation property of fibres was also predicted from stress to strain data. The results showed that the handsheets were hydrophobised and alkyl esters were formed. The presence of trace amounts of carboxylic acid in the treated fibre was attributed to the hydrolysis of alkyl anhydrides during the reaction process. The treated fibres required less energy during refining, improved moisture resistance and good sheet formation compared to handsheets formed from untreated flax shives pulps. Chemically treated and refined shives closely resembled chemithermomechanical pulp of flax shives and can be a potential alternative source for wood pulp. (C) 2002 Elsevier Science B.V. All rights reserved.