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This information is for general knowledge. If you have a critical application check with supplier. Different manufacturing processes change the feel, appearance, and strength of ropes. only.

Synthetic Rope Comparison

Comparing the Major Synthetic Rope Materials

When deciding what rope best suits your need, it is often a matter of compromise.

There are 5 major synthetic ropes in use for boat and marine applications. Polypropylene, Polyester, Nylon, UHMWPE (Ultra High Molecular Weight Polyethylene) and Aramids. Each has outstanding virtues and each has faults.

Rope Manufacturers often combine different fibers and add specialized coatings in order to benefits from the good quality of each material.

Synthetic Rope Comparison Table

MATERIAL	ADVANTAGES	DISADVANTAGES	USES
Polypropylene	Floats Inexpensive Not sensitive to chemical attack Tough, abrasion resistant Resists wetting No loss of strength in water	Degrades in UV Not very strong Stiff, knots come undone (some softer braids are made) Low melting point Stretches (not as much as Nylon)	Dinghy Mainsheets, Rescue and tow lines, Water ski lines
Nylon Perlon	Good UV Resistance Absorbs shock (stretches) Good chemical resistance Moderately priced	Very stretchy Weaker in when wet Smoke is nasty (cyanide)	Anchor lines, Some tow lines, Mooring lines, Safety lines
Polyester	Excellent UV resistance Moderate stretch Abrasion resistant Good chemical resistance Keeps strength when wet Moderately priced Not unpleasant to handle	Sinks Quite stiff	Best all round line when you don't need ultra strong or light lines. Most common halyard rope material for boat use.
UHMWPE Spectra, Dyneema, Nomex	Very Strong Doesn't wet Very Chemically resistant Abrasion Resistant UV resistant Light and floats Good flex fatigue resistance	Slippery Low melting point Creeps under constant load Ropes tend to distort under load unless coated Expensive	High performance yacht lines
Aramid Kevlar, Twaron, Technora	Very Strong Low stretch Low creep Fire Resistant Good chemical resistance Cut resistant	UV sensitive Sensitive to shock loads Sensitive to Chlorine Poor flex/fatigue resistance Weakened by knots Sensitive to internal friction Expensive	Winch lines, Sometimes as steel rope replacement where weight saving is important. Not much used in boats.

This synthetic rope comparison is offered for general information. New materials are developed every day.

I try to be accurate and check my figures, but mistakes happen. Check the suitability of any material against the technical information provided by the manufacturer.

Many of the strength figures I quote come from Wikipedia or from the actual manufacturer. I sometimes make mistakes (!!?!) in transcribing the data.

email me if you find mistakes, I'll fix them and we'll all benefit: Christine