Deciding which type of rope is best for a given use requires an understanding of the characteristics of the various materials used in making ropes. For centuries, rope was made of fibers from plants found in nature and easily cultivated—biodegradable and sustainable. Today, the rope market is dominated by synthetic ropes manufactured using man-made materials.
As this Guide illustrates, the physical properties of natural and synthetic materials translate into the capabilities and shortcomings of ropes made from them. A rope that might be well-suited for one purpose might be absolutely the wrong choice for another. (Of course, cost also enters into the selection process). Once you have found what you need from our guide you can check out our rope selection to find the perfect rope for your industry needs.
Natural Rope Materials
The natural materials most commonly used in rope-making are cotton, flax, jute, manila, and sisal.
Cotton
Cotton, is one of the first fibers used to make rope, dating back at least 5,000 years to ancient Egypt. The cotton plant is also native to South America, Central America, Mexico, and the American Southwest. It has long been a major crop of the American Southeast.
The greatest advantages of cotton are its flexibility, soft feel, and relative strength for its lightweight feel. These properties make cotton rope a good choice for comfort. It’s easy on the hands, and its flexibility makes it a breeze to tie into knots that will hold firmly under load. Cotton rope is used for a wide variety of purposes, from clotheslines to gardening and craft projects to tying down lighter loads for transport.
On the downside, cotton swells in high humidity and absorbs liquid, which makes it susceptible to mold, mildew, and rot. This, of course, limits the utility of cotton rope in damp environments.
Flax
Flax fibers are extracted from the flax/linseed plant, which is one of the world’s oldest cultivated crops. Native to Asia and the Mediterranean, most of the flax used in the U.S. today is grown in and imported from Canada.
Like cotton, flax is surprisingly strong for its weight. It stays cool when temperatures rise, absorbs moisture, and doesn’t stretch much. While rope made from flax isn’t the strongest rope on the market, its 285-pound breaking point is impressive, considering how thin it is.
Because of its flexibility and heat resistance, flax rope is commonly used for tying cables on film sets, in TV studios, in IT departments, and anywhere else where tangles of cables can be unsightly or cause trip and fall hazards. Flax rope is also used in the natural furniture market as a way to strengthen joints without metal fasteners and to create rustic woven chair seats. Its rustic look and feel makes it a good choice for interior décor purposes. And if you have “fur babies,” you may find it interesting that flax rope is commonly used in making pet toys.
Jute
Jute is a natural fiber known for its pliability, durability, and modest cost. It comes from the bark of the white jute plant that is native to Southeast Asia.
Jute is made into twine as well as ropes of varying thicknesses. Ropes of different thicknesses have different strength ratings. While jute twine is used where strength is not a requirement, ½ inch jute rope has a strength rating of 425 pounds. The pliability of jute rope makes it easy to form secure knots, and its strength makes it a good option for ting down light loads. Like ropes made of flax, jute ropes are used as cable ties to prevent accidents and for DIY and crafting projects.
Manila
Manila is extracted from the tropical abaca plant, native to the Philippines. It is the strongest of all natural fibers used in rope-making. All rope has a breaking point. But unlike synthetic ropes, manila ropes don’t snap under heavy loads, which can be a safety hazard. They merely begin to fray.
Manila rope is flexible and easy to tie into knots. Plus, it contracts when wet, which will tighten up any knots. Manila is also resistant to damage from saltwater, making it a good choice for many marine tasks. In fact, manila rope is a popular choice for a general utility rope inside and outdoors.
But, be mindful that long-term exposure to the elements is not a good idea for this rope because it is highly absorbent and vulnerable to UV damage. Leaving manila rope outdoors for a long period of time can cause its surface to become hard and begin to rot.
Sisal
Sisal comes from the flowering agave sisalana plant, which originated in southern Mexico but spread through cultivation to hot and arid regions around the world. It offers outstanding strength for a natural fiber, with less stretch than most other natural rope materials. It’s stiff, tough, and UV resistant, but its rough texture can make it uncomfortable to handle, especially for people with sensitive skin.
Because it has relatively little give, sisal rope will hold firm when knotted or used for bundling or tie-down purposes. Sisal is not treated with any chemicals and is naturally antimicrobial, which makes it good for use in agriculture and around animals. Scratching posts for cats are typically made by winding sisal rope around a wood post or frame.
Synthetic Rope Materials
In this section, we’ll look at popular synthetic materials used in rope-making: nylon, polyester, polypropylene, and UHMWPE.
Nylon
Created in the 1930s, nylon (polyamide) was the first synthetic material used in rope-making, specifically in manufacturing nylon cords for parachutes and tow lines for small planes during World War II. Nylon is very strong and resistant to abrasion, mold, mildew, and UV damage.
Nylon rope holds up well in outdoor applications such as towing and pulling, winching, tie-down tasks, and flagpole rope. It has a little give and is flexible enough to form knots with ease. It’s ideally suited for uses that require high shock absorption.
Be aware that when nylon rope is exposed to damp or wet conditions for extended periods, it tends to stiffen and become more difficult to handle.
Polyester
Polyester was initially used for fabric, but didn’t become a common rope material until the 1950s. To a greater or lesser degree, polyester has many of the same characteristics as nylon. It has roughly the same strength, too, but lacks nylon’s stretch and dynamic shock absorption. Polyester and nylon are about equal in moisture and chemical resistance, but polyester has better UV and abrasion resistance.
Polyester rope is a natural choice for sailing and boating, lifting, and even towing, rigging, and general tie-down applications. The limited stretch of polyester rope means it is more secure than nylon to work with when managing heavy loads.
Polypropylene
Polypropylene was invented in the mid-1950s and was in commercial production by 1957. When polypropylene rope was introduced, it quickly became known as a reliable, versatile general-purpose rope because of its strength, buoyancy, imperviousness to rot, high melting point, and smooth hand feel. For example, it’s commonly used to create swimming lanes and in outdoor activities such as camping and boating.
Polypropylene rope is manufactured in a number of different colors, so it’s easy to find the color that provides the visibility needed for a particular task. For example, bright yellow rope stands out in outdoor settings that are dominated by browns and greens, making it a good choice for crowd control, boating, and use on construction sites.
Polypropylene rope does have some drawbacks, though. Its stiffness and slipperiness make it difficult to tie most kinds of knots. And despite its high melting point, extended exposure to UV light and extreme heat can cause discoloration and fraying of polypropylene rope.
UHMWPE
Ultra-high-molecular-weight polyethylene (UHMWPE) rope has been a commercially viable product since the early 1990s. UHMWPE is a family of synthetic fibers sold under brand names such as Dyneema and Spectra.
UHMWPE is widely regarded as a good alternative to wire cables in applications such as automotive and marine towing. It’s safer than wire because its lower mass and lack of dynamic shock absorption mean there’s no snap-back upon breaking. It’s considerably lighter than wire cable, with a high strength-to-weight ratio. And unlike wire, UHMWPE rope does not kink, which prevents weak spots from developing. Because UHMWPE is not as dense as water, marine cables made from it are easy to spot and recover.
However, UHMWPE rope is vulnerable to damage from UV exposure and high heat. It does not hold knots well, and once it has stretched, it doesn’t return to its original length. Not being dynamic, it should not be used in applications that require a rope with good shock load absorption.
Rope Material Selection Criteria
Understanding the physical properties and performance characteristics of various rope materials is a big part of choosing the right rope for a particular use. Consider the relative merits of different rope materials in terms of their:
- Strength
- Weight
- Shock load ability
- Buoyancy
- Elongation at break
- Flexibility
- Water resistance
- UV resistance
- Abrasion resistance
- Chemical resistance
- Electrical conductivity resistance
Rope Construction
Rope construction is another key factor in rope selection. It can enhance the natural properties of the rope material. Here are the most common constructions:
3-Strand Twisted
Three strands of the rope material are twisted together to form a durable, flexible, easy-to-handle rope.
Single Braid
Strands are braided together without an inner core, which is why this construction is also known as “hollow braid.” Single braid ropes don’t kink and are easy to splice.
Double Braid
This rope construction consists of a braided core inside a braided outer cover, not necessarily of the same material. For example, the core material might be chosen for its strength, while the cover material might be highly heat resistant. How tightly twisted the core material is determines whether the rope is static or dynamic.
Other Constructions
Some companies have developed their own proprietary or patented rope designs and braiding technologies. This is common when new synthetic rope materials are introduced. There’s an entire discipline within materials science devoted to engineering new fibers and polymers to create new rope designs and manufacturing processes. Ongoing innovation leads to continuous improvement in rope characteristics and performance, with each generation of products being stronger, lighter, and more resistant to adverse environmental factors.
Rope Selection Strategy
Choosing the right rope for a given task is driven by the nature of the task. What does the task demand in terms of rope performance? Do you need a rope that can lift a heavy load? Does the task involve the use of a pulley or winch? Will the rope be used in a wet environment? Etc.
Understanding the requirements of the task makes it relatively easy to determine which materials and rope constructions best meet them. Consider a rope’s load rating, strength-to-weight ratio, resistance to certain environmental factors, buoyancy, high visibility, and other characteristics that align with the task requirements.
Cost, of course, also enters into the picture. You may have to make a tradeoff between performance and affordability if you have budget constraints.
Excellent Rope Selections with SEACO
Remember, the ideal rope depends on the circumstances in which it will be used. So, the next time you find yourself looking for a rope that will suit your industry’s task, let our guide be your compass.
Here at SEACO, we’re passionate about ropes. We offer a vast selection of natural and synthetic options in every thickness and construction imaginable. With our expert advice and top-quality products, you’ll find the perfect product for your application. Browse our rope selection here or contact us for more information.