Surface Modification of Cellulose Acetate with Cutinase and ...
Surface Modification of Cellulose Acetate with Cutinase and ...
Surface Modification of Cellulose Acetate with Cutinase and ...
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1. Synthetic fibres<br />
<strong>Surface</strong> <strong>Modification</strong> <strong>of</strong> Synthetic Fibres - Introduction<br />
Synthetic fibres are defined by the International Organization for St<strong>and</strong>ardization (ISO)<br />
as fibres manufactured from polymers built up from chemical elements or compounds,<br />
in contrast to fibres made from naturally occurring fibre-forming polymers.<br />
Synthetic fibers represent almost 50% <strong>of</strong> the worldwide market <strong>of</strong> textile fibers.<br />
Common synthetic fibres include: acetate, nylon, modacrylic, olefin, acrylic <strong>and</strong><br />
polyester. This chapter will focus on molecular biotechnology approaches aiming at the<br />
surface modification <strong>of</strong> poly(ethylene) terephthalate, polyamide 6,6 <strong>and</strong> acrylic.<br />
2. Polyester<br />
2.1. Poly(ethylene terephthalate) (PET)<br />
Polyester fiber, specifically poly(ethylene terephthalate) (PET), is the largest volume<br />
synthetic fiber produced worldwide. The total volume produced in 2002 was 21 million<br />
metric tons which corresponds to 58% <strong>of</strong> synthetic fiber production worldwide.<br />
Poly(ethylene naphthalate) (PEN); poly(butylene terephthalate) (PBT); poly(propylene<br />
terephthalate) (PPT); <strong>and</strong> poly(lactic acid) (PLA) are examples <strong>of</strong> other polyesters<br />
commercially produced in fiber form, however <strong>with</strong> lower volumes <strong>of</strong> production<br />
compared to PET.<br />
PET is the condensation product <strong>of</strong> terephthalic acid (TA) <strong>and</strong> ethylene glycol. The key<br />
to successful PET polymerization is monomer purity <strong>and</strong> the absence <strong>of</strong> moisture in the<br />
reaction vessel (Brown <strong>and</strong> Reinhart, 1971).<br />
The technology that allowed for the cost-effective polymerization <strong>of</strong> PET was the<br />
development <strong>of</strong> low-cost <strong>and</strong> pure TA from mixed xylenes in the mid-20th century<br />
(McIntyre, 2003). The alternative to TA, <strong>and</strong> the monomer <strong>of</strong> choice before the<br />
availability <strong>of</strong> low-cost TA, was dimethyl terephthalate (DMT). While direct<br />
esterification <strong>of</strong> TA is the preferred method <strong>of</strong> PET synthesis, ester interchange between<br />
DMT <strong>and</strong> ethylene glycol is still utilized in some PET manufacture, partially because <strong>of</strong><br />
local choice <strong>and</strong> partially because DMT is a product <strong>of</strong> polyester recycling by<br />
methanolysis or glycolysis (Milgrom, 1993). The second monomer, ethylene glycol, is a<br />
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