Is Nylon Waterproof?

Are you wondering if nylon is waterproof?

Maybe you’re planning to go kayaking, snorkeling, or fishing and, of course, want waterproof outdoor gear or a backpack that will keep your stuff dry. You’re aware nylon is a versatile material used in making everything from clothing items to household items to luggage, umbrellas, you name it. Still, you wonder just how well it holds up against fluids.

Here at Waterproved, we understand your dilemma and want to help. That’s why in this article, we will discuss how waterproof nylon fabric really is.

Where is Nylon Commonly Used?

When it comes to where nylon is commonly used, it’s almost easier to say where nylon is not used. Think about it. There’s nylon in nearly every item you can think of – toothbrushes, bedspreads, umbrellas – the list is endless. It’s no wonder nylon is one of the most popular man-made materials used in the United States.

Below are some common uses of nylon:

  • Apparel: Due to its good dimensional stability, it’s used to make gloves, stockings, swimwear, and hosiery.
  • Clothing: T-shirts, foundation garments or shaping underwear (such as corsets), lingerie, and swimwear.
  • Domestic use: Nylon is widely used in carpets, upholstery, draperies, bedspreads, and ropes and cords.
  • Industrial use: High tenacity nylons are used to manufacture fishing nets, sewing thread, parachute fabrics, airbags, tarpaulins, conveyor and seat belts, tire cords, and ropes.
  • Outdoor gear: Such as backpacks, hammocks, tents, sleeping bag lining, shoes, hiking boots, ski boots, fishing floats, tarps, and eyewear.
  • Outdoor wear: These are comfortable clothes you wear for hiking, camping, backpacking, skiing, climbing, and so on, including rainwear, cyclewear, windbreakers, and activewear (comfortable casual wear suitable for sports or exercise).

Technical Makeup of Nylon

Below is a breakdown of the properties of nylon:

  • Density: Density is the mass of a substance per unit volume. Nylon has a density of 1.13 to 1.35g/cm3.
  • Glass transition temperature (for Nylon 66) refers to the temperature range where the substrate converts from its rigid glassy form to a soft material. It’s measured in terms of modulus or stiffness. The glass transition temperature for nylon is 1130F (450C).
  • Maximum continuous use temperature: This refers to the maximum acceptable temperature beyond which electrical properties (such as dielectric strength) or mechanical properties (such as tensile strength) of a part or item made from a material become degraded over the tested product’s reasonable lifetime. Nylon has a maximum continuous use temperature of 302 to 3650F (50 to 1850C).
  • Melting point: This is the temperature at which a substance can exist at equilibrium, after which it converts to liquid. For nylon, it’s 374 to 6620F (190 to 3500C).
  • Moisture Regain: This is the amount of wetness a material can reabsorb after drying and is expressed as a percentage of the weight per weight. Nylon has a moisture regain of about 4%.
  • Notched Izod impact strength: This refers to a material’s resistance to impact; how much energy you require to break or tear the fabric. Nylon has a notched impact strength of 5 to 13 Kj/m2.
  • Tenacity: Tenacity is the maximum mass you can put on the material before it breaks. Nylon has a tenacity of 3.5 to 7g/d under dry conditions and 2 to 6.2g/d under wet conditions.
  • Tensile strength: This is the ability of a material to withstand stretching without rupturing, measured as force per unit area. Nylon has a tensile strength of 90 to 185 N/mm2.
  • Thermal expansion coefficient of expansion (expansivity): This refers to the expansion per unit increase in temperature. Nylon has a thermal coefficient of expansion of 80 X 10-6.

Is Nylon, In Its Rawest Form, Waterproof?

No, nylon is not waterproof in its most basic form.

If we consider nylon’s molecular properties, it’s a hygroscopic material, meaning rather than resist fluids passing through it, it absorbs liquids and allows them to pass through it. And higher humidity boosts the rate of absorption.

When immersed in water, nylon acts much like a sponge and will absorb the water extremely fast until it reaches a saturation point. After it has reached the saturation point, no amount of humidity will cause it to absorb more liquid.

In addition to absorbing water when submerged or poured on it, nylon will also absorb moisture directly from the surrounding air.

What Properties Can Make Nylon More Water Resistant?

Some properties can make nylon more water resistant (we cover the difference between water resistant and waterproof here too). Let’s cover them!

Thread count

Thread count refers to the number of threads (both lengthwise and widthwise) woven together per square inch. And just a side note, the lengthwise threads are also known as warp, and the widthwise threads as weft.

So, for example, a thread count of 300 means 150 threads woven lengthwise and 150 threads woven widthwise.

Thread count is a great property in fabric and not just a marketing gimmick aimed at getting you to buy Egyptian cotton sheets. It improves not only a fabric’s breathability and comfort but also its water resistance.

That said, the threads’ quality matters too, and both quantity and quality must go hand-in-hand for the high thread count to be of any real value.


Increasing the weight of materials boosts water-resistance. This can be attributed to more of the cellulosic particles being exposed, which tend to absorb water.

Tests on the impact of weight on water resistance done on kenaf and bamboo reinforced polythene composites displayed a significant difference in the amount of water absorbed and tensile properties. The tensile strength and ability to resist water both improved with the increase in fiber weight.

Of course, the weight fraction and size of the natural fiber used are key.


According to researchers at ETH Zurich, making the material more flexible and elastic increases its water resistance by boosting its hydrophobicity. The study conducted on suspended films showed that the films with enhanced elasticity and thickness repelled water about 1.5 times more than the same films mounted on a substrate.

Hydrophobic surfaces naturally repel water, causing droplets to form.

Interestingly, the inspiration for hydrophobic coatings to increase flexibility is borrowed from nature.

There are several surfaces in nature whose super-hydrophobicity is complemented by flexibility. Good examples are butterfly wings, insects, some birds, and certain plant leaves.

To understand how elasticity makes it more waterproof, let’s consider a water-repellent material in the rain.

When raindrops collide with an elastic surface, the impact is cushioned, causing the droplets to bounce back with less impact. But if the surface isn’t flexible, the droplets bounce back harder, and so the surface gets wet more easily.

How to Make Nylon Waterproof

Clearly, water resistance is not one of nylon’s strong properties. But the good news is, there are ways to make nylon waterproof. These include:

●  Improving production techniques: Tightening a material’s weave and increasing the weight are techniques used to make nylon waterproof. Such techniques minimize and eliminate the amount of water that can pass through a fabric, improving its water resistance and overall quality.

●  Adding external waterproof coating or sealant: There are various waterproof agents available for nylon, including rubber, urethane, and DWR. These waterproof agents prevent fluid flow through fabrics and cause the water to bead off the surface.

While nylon is not waterproof, it makes a great base material for many waterproof products. In a future article, we’ll share some of our favorite strategies for waterproofing nylon.

The Last Drop

Have questions about nylon? Shoot us a message! We love talking about this stuff.

If you’re interested in the waterproof properties of other fabrics, check out our other articles below.