"Polytex" is a high-quality 3-strand polypropylene rope manufactured by Langman Ropes in The Netherlands. The rope is designed with enhanced UV-stabilisation and constructed with additional twine to give a very abrasion-resistant rope, well-suited to running rigging on classic sailing boats.
The replica of General Lafayette's frigate L'Hermoine, recently launched in France (see video below), used "Polytex" rope for high-load parts of the rigging. Incidentally, Langman Ropes supplied of all ropes for the rebuilding of L'Hermoine - some 25km or rope.
Since it's made from polypropylene "Polytex" is very light compared to similarly-sized ropes made from other materials. It will float in water.
"Polytex" is sold by the metre or on spools of 220 metres. Discounts apply for bulk purchases of 50m or more - see above for details.