Surface Modification of Cellulose Acetate with Cutinase and ...

Subchapter 2.1
major material of commerce, produced by the oxidation of ethylene followed by ring
opening with water. The large-scale production of all PET monomers assures low-cost
polymers and makes competition from new compositions of fiber-forming polymers
very difficult.
2.2. PET fibres properties
PET fiber has excellent properties like convenient processability and tailorable
performance, associated with low cost production. Undesired characteristics of the most
widely used synthetic fibres based on polyethyleneterephthalates (PET) include
difficulties in finishing, build-up of electrostatic charge, the tendency to pilling,
insufficient washability and wearing comfort due to low water absorbency (East, 2005).
Although alkaline treatment of PET can easily increase hydrophilicity, favourable
properties such as strength are negatively influenced (Zeronian and Collins, 1989).
3. Polyamides
3.1. Aliphatic polyamides
Aliphatic polyamides are macromolecules whose structural units are characteristically
interlinked by the amide linkage –NHCO-. The nature of the structural unit constitutes a
basis for classification. Aliphatic polyamides with structural units derived
predominantly from aliphatic monomers are members of the generic class of nylons,
whereas aromatic polyamides in which at least 85% of the amide linkages are directly
adjacent to aromatic structures have been designated aramids (Reimschuessel, 1998).
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3.1.1. Polyamide 6,6
Among various nylon compositions, nylon-6,6 is by far the most important polyamide
for the commercial production of fibers. Nylon 6,6 is a copolymer of diamine
(hexamethylene diamine) and diacid (adipic acid). These molecules alternate along the
chain, each donating 6 carbons to the polymer.