Abstract:

The article gives an account of investigations on the preparation of highly porous dibutyrylchitin fibres containing tri-calcium phosphate (â-TCP) or nano-hydroxyapatite (nano HAp). Fibers were spun from 16% dibutyrylchitin (DBC) solutions in ethanol (content of ethanol: 67 - 78%). The fibers obtained showed a sheath/core structure; the sheath being a solid skin while the core presented itself as a macro-, micro- and nano-porous interior filled with air. DBC was used with an intrinsic viscosity [η] of 1.96, 2.19 & 2.42 dl/g and a content of b-TCP or nano HAp in the amount of 6 and 11.7% on DBC, respectively. The impact of ethanol concentration in the spinning solutions was investigated with respect to forming conditions: as-spun draw ratio, draw ratio, spinning speed and pH of the coagulation bath upon the morphology structure and mechanical properties of the fibers. Lab-scale wet spinning was applied, which produced highly porous fibers (DBC/HPCF) characterised by a tenacity of 4.0 - 10.5 cN/tex and elongation of 10 - 14.5% (conditioned state). The porosity of the fibres was assessed by mercury porosimetry, and as a comparison by digital analysis of SEM images of the fibre cross-section. The novel fibres may be used as material in the construction of bone implants, hygiene products and in various technical applications.