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Lyocell: Properties and applications

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This is a comprehensive article covering a wide range of characteristics of this widely used material. The definition of lyocell, a cellulose fibre obtained using an organic solvent spinning process is given together with explanations of the terms used. Physical properties noted include tensile strength, microscopic appearance, average diameter, and density. It is noted that is the strongest known cellulose fibre even when wet when it is stronger than cotton fibre. Table 2 lists the physical properties of lyocell fibres that are compared with three other fibres. Table 1 shows the manufacturer, country of manufacture and trade names for a variety of commercial fibres. Selected physical properties such as thermal, chemical and physiological properties are briefly noted. The penultimate paragraph discusses relatively new material, tencel denim, an indigo dyed material with better softness than traditional denim made from cotton. Table 3 lists the large variety of personal, home and industrial uses for lyocell.
... The calculated stability constants for the complexations between PZQ and a-, b-and g- CDs were 56.18, 396.91 and 15.17 M − 1 , respectively . The higher stability constant for the b-CD complex (396.91 M − 1 ) may reflect spatial compatibility of the guest PZQ molecule and the strength of the interaction by partial fit into the CD cavity (Szejtli, 1984 ). The lower stability constants given by the a-and g-complexes suggest weaker more labile interactions which would result in premature release of the drug. ...
... The lower stability constants given by the a-and g-complexes suggest weaker more labile interactions which would result in premature release of the drug. Only the b-CD complex had a stability constant within the limits reported to be suitable for pharmaceutical utilisation (Szejtli, 1984 ). Computer-aided modelling and 1 H NMR data indicated the formation of 1:1 complexes. ...
... M − 1 ), resulting in the fastest dissolution. Inclusion complexes with small stability constants have also been observed by other investigators (Uekama et al., 1983; Szejtli, 1984; Duchêne and Wouessidjewe, 1990), who have reported faster dissolution rates and extensive dissociation upon dissolution. The low stability constant for the a-CD complex suggests both a high solubility and a fast dissolution rate. ...
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