Surface Modification of Cellulose Acetate with Cutinase and ...

Subchapter 2.1
End uses include sweaters, hand-knitting yarns, rugs, awnings, boat covers, and beanies;
the fiber is also used as a precursor for carbon fiber.
4.1. Polyacrylonitrile fibres Properties
Polyacrylonitrile (PAN) fibres are characterised by a combination of desirable
properties such as high resistance to outdoor exposure and chemicals, excellent
elasticity, natural-like aesthetics properties and colour fastness. However, due to its
hydrophobic nature, PAN fibres also exhibit undesirable properties such as
uncomfortable hand and static charge accumulation (Lulay, 1995; Frushour and Knorr,
1998). The quality and properties of acrylic fibres can be improved by chemical and
physical means using co-monomers, additives and polymer blends (Burkinshaw, 1995).
The surface modification is also considered an important tool to improve the quality and
the processing properties of PAN fibres (Battistel et al., 2001). Traditional processes
used to modify polymer surfaces are based on the addition of strong chemical agents.
The application of enzymes towards the modification of this polymer has major
advantages compared to those agents, such as milder reaction conditions, easier control,
specific non-destructive transformations, and environmental friendly processes.
5. Surface modification of synthetic fibres
Major characteristics of synthetic fibers are their excellent strength, high hydrophobicity
and low reactivity with most common chemical agents. The suitability of fibers for a
given end-use application depends on several factors including mechanical behavior,
chemical resistance, dimensions, and surface characteristics. For instance, the low
hydrophobicity makes those fibers less suitable to be in contact with the human skin,
and the low reactivity makes the fiber unsuitable to act as carrier to other chemical
finishing agents. The interest in fiber surface modification is related to the introduction
of specific properties required for a certain application. The desired properties may
range from improved adhesion to response to stimuli from the environment.
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