ORIGINAL PAPER Regeneration of fibres from alkaline solution containing enzyme-treated 3-allyloxy-2-hydroxypropyl substituted cellulose Marianna Vehvila¨inen . Taina Kamppuri . Harri Seta¨la¨ . Stina Gro¨nqvist . Marja Rissanen . Mari Honkanen . Pertti Nousiainen Received: 16 December 2014 / Accepted: 3 May 2015 / Published online: 10 May 2015 Ó Springer Science+Business Media Dordrecht 2015 Abstract The aim of this study was to regenerate fibres from the alkaline cellulose solution containing 3-allyloxy-2-hydroxypropyl substituents. Enzyme- treated cellulose was modified in alkaline aqueous tert-butanol (tBuOH) using allyl glycidyl ether (AGE) as the modification reagent. 3-allyloxy-2-hydrox- ypropyl substituted (AHP) enzyme-treated cellulose with DS A 0.05 was obtained. Enzyme-treated cellu- lose without (reference) and with substituents were dissolved in sodium zincate using the freezing-thaw- ing cycle. The reference solution alone and the mixture solutions containing 10 or 25 % of the AHP cellulose were regenerated into cellulosic fibres using the wet spinning technique. The solutions containing 100 or 50 % of the AHP cellulose did not form fibres in acidic bath. The 10 % share of AHP cellulose did not affect the mechanical properties of the fibres (1.5 cN dtex -1 ), while the 25 % share decreased the tenacity slightly (1.3 cN dtex -1 ). Elongation of the fibres ranged from 18 to 22 %. The 10 and 25 % shares of AHP cellulose increased the water holding ability of fibres by 12 and 33 %, respectively. According to FESEM the fibre structures are composed of nanosized fibrils. Keywords Enzyme-treated cellulose  3-Allyloxy- 2-hydroxypropyl cellulose  AHP cellulose  Wet spinning  Regenerated fibres  Biocelsol  Fibril structure Introduction Native cellulose fibre has a complex layered structure, high degree of polymerisation (DP), and strong intra- and intermolecular hydrogen bond network which limit its dissolution and further processing (Klemm et al. 2005). As a consequence, the chemical modifications of cellulose through substitution reactions are important routes for the commercial cellulosic products. The two main reactions used are esterification and etherification of cellulose. Industrially, the most important ester is cellulose xanthate which is an intermediate product in the viscose process. It is formed through a carbon disulphide (CS 2 ) treatment of mercerized cellulose and it enables the dissolution and subsequent regeneration of the modified cellulose in aqueous environment (Wilkes 2001). The other commercial cellulose esters do not commonly dissolve in water-based solvents (Heinze and Liebert 2001). The industrially important cellulose ethers include methyl cellulose (MC), carboxymethyl cellulose (CMC) and hydroxyethyl cellulose (HEC) (Klemm et al. 2005). Depending on the degree of M. Vehvila¨inen (&)  T. Kamppuri  M. Rissanen  M. Honkanen  P. Nousiainen Materials Science, Tampere University of Technology, P.O. Box 589, 33101 Tampere, Finland e-mail: marianna.vehvilainen@tut.fi H. Seta¨la¨  S. Gro¨nqvist VTT Technical Research Centre of Finland, P.O. Box 1000, 02044 Espoo, Finland 123 Cellulose (2015) 22:2271–2282 DOI 10.1007/s10570-015-0647-6