Here's the short version: If you're sourcing performance fabrics, Coolmax is polyester with a specific moisture-wicking engineering, nylon is tougher but holds onto moisture, and plain polyester is the cheap workhorse. That's the core of it. But if you're managing procurement for a company—especially a smaller one where every dollar matters—the choice isn't as simple as the marketing makes it seem.
I'm an office administrator for a mid-size company. I manage all our uniform and promotional product ordering—roughly $60k annually across about a dozen vendors. I report to both operations (who care about utility) and finance (who care about unit cost). So I've had to navigate these material decisions from a practical standpoint, not a textile engineer's. Here's what I've found after processing probably 200+ orders for stuff made from these materials.
First, a quick clarification on what Coolmax actually is, because I think this trips a lot of people up. Coolmax is polyester. But not all polyester is Coolmax. Coolmax is a proprietary fiber from The Lycra Company (formerly Invista) that uses a multi-channel or cross-section fiber design. The idea is to increase surface area for moisture to evaporate faster. Regular polyester is a solid cylinder filament. So when you see something labeled 'Coolmax,' you're paying for that specific engineering, not for a fundamentally different material class.
I learned this the hard way. About three years ago, I sourced a batch of polo shirts for our field service team. The catalog said 'moisture-wicking performance fabric.' I assumed it was Coolmax-tier. It wasn't. The shirts were cheap, felt fine out of the package, but after three washes, the 'performance' was gone. Guys complained of feeling clammy in the summer heat. I looked like a bad buyer. Turns out it was low-grade polyester with a topical wicking finish that washed off. The fabric held onto oil-based stains, too—something I didn't anticipate.
So what's the actual difference when you're sitting across from a supplier or scrolling through a B2B catalog?
Nylon vs. Polyester vs. Coolmax: The Practical Differences
Let's cut the technical jargon. Here's what matters to a buyer who has to justify a purchase to a VP who doesn't care about fiber cross-sections.
Polyester (the baseline): It's durable, cheap, dries fast, and resists wrinkles and shrinkage. Its biggest weakness? It doesn't breathe well without fabric engineering. That's why cheap polyester shirts feel like wearing a plastic bag. It also holds onto body oils and odors more than other synthetics. If cost is your only metric, standard polyester is the cheapest option per yard. For things like aprons, tote bags, or basic outer shells where breathability isn't the priority, it's fine.
Nylon: Tougher than polyester. Much better abrasion resistance. Used for jackets, backpacks, and gear that takes a beating—think work pants, equipment covers, heavy-duty outerwear. The catch? Nylon absorbs more water (up to 4% of its weight). So if you're in a humid environment or need fast-drying, nylon works against you. It also degrades under UV light faster than polyester. Nylon is for durability-first applications, not for moisture-wicking. I've ordered nylon work pants that held up great to kneeling on concrete, but the same material in a shirt would be a mistake.
Coolmax: Engineered polyester with specific fiber cross-sections (like a plus sign or four-channel shape). This wicks moisture away from the skin much faster than regular polyester because capillary action is stronger with the increased surface area. It also dries faster. The trade-off? Higher cost per yard—usually in the range of 15-30% more than standard polyester for comparable GSM/weight—and lower abrasion resistance than nylon. But for activewear, base layers, socks, and any garment where sweat management matters, Coolmax is the clear win.
Here's a scenario that made this concrete for me: We ordered custom socks for a team that does outdoor installation work. Standard cotton socks were causing blisters and complaints. We spec'd a nylon-reinforced sock with a Coolmax moisture-wicking liner. The nylon provided the durability in the heel and toe (abrasion resistance), and the Coolmax pulled sweat away from the foot. The per-pair cost was about $1.20 more than the all-cotton alternative. Finance flagged it. I walked them through projected reduction in reorder frequency (socks lasted longer) and fewer complaints. We approved it. The reorder rate from that same team dropped by about 60% because the product actually worked. Saving $1.20 per pair initially would have cost us more in re-sourcing later—a classic story of being penny-wise and pound-foolish.
What About the Other Keywords in This Search?
I noticed the query also mentions h and m coolmax t shirt, lettia coolmax fleece girth, olefin fabric outdoor cushions, and velvet mary janes women. These are diverse categories, but they all connect to a broader point: material choice depends heavily on the application context.
H&M Coolmax T-shirt: H&M uses Coolmax in some of their activewear lines. This tells you it's a consumer-facing application where the Coolmax branding itself is a marketing differentiator. For a B2B uniform program, this signals that the technology is available at a consumer-friendly price point, but the industrial-grade Coolmax (like Lycra Co. branded) is usually what you want for heavy-duty team uniforms. The H&M version might be a lower fabric weight or blended with cotton to hit a retail price.
Lettia Coolmax Fleece Girth: This is an equestrian product (a girth strap for a horse saddle), and it's probably a specific branded product using Coolmax in the lining. It's a niche application—equestrian gear demands high moisture-wicking for horse comfort and durability against friction. This tells you that Coolmax has specialized applications beyond activewear, and that a dedicated product (like Lettia) may justify a premium price based on performance guarantees.
Olefin Fabric Outdoor Cushions: Olefin (polypropylene) is a completely different beast. It's not polyester or nylon. Olefin resists moisture and stains better than both, is UV-resistant, and is cheap. But it has low heat resistance (melts at lower temps) and feels less 'soft' to the touch. For outdoor cushions where rain and sun are the enemies, olefin is actually superior to polyester for durability. This is a case where the 'less popular' material wins for the specific use case. If you were comparing olefin vs. polyester for marine cushions, olefin would win on weather resistance. But if you need structure and softness for indoor upholstery, polyester has the edge.
Velvet Mary Janes Women: This isn't synthetic performance fabric at all—it's a dress shoe. The 'velvet' is likely polyester or nylon pile (or cotton) for a luxury aesthetic. The 'Mary Jane' style is about fashion, not function. This keyword in the same search string suggests you're maybe exploring a whole retail category, or the SEO targeting is broad. For a B2B buyer, the lesson is: know the end-use before spec'ing material. Specifying velvet for a work boot is wrong. Specifying Coolmax for a dress shoe is wrong. Match material to use case.
Which One Should You Choose?
This is where my answer gets specific to your situation:
- For base layers, socks, activewear, or anything next to skin where sweat is a problem: Engineered polyester (Coolmax) is best. Nylon would hold moisture. Standard polyester would work but less effectively. Expect to pay a 15-30% premium over basic polyester for genuine branded Coolmax.
- For outer shells, bags, straps, or high-wear items: Nylon is the winner for abrasion resistance. Nylon rates better on the Martindale abrasion test (a textile test with a standard specification). But don't skimp on UV protection additives if the gear will be in direct sun.
- For budget-conscious bulk uniforms where performance is secondary: Standard polyester is fine. But test a sample first—not all polyester is equal. The 'heathering' effect of spun polyester yarns can help with durability and feel.
- For outdoor furniture, marine, or wet environments: Olefin beats both nylon and polyester for weather resistance. It's not a like-for-like swap because it has a different hand feel and lower heat tolerance, but for cushions and awnings, it's often the default.
My experience is based on about 200 mid-to-high volume orders for a mix of uniform, promotional, and equipment items. I can't speak to how this applies to luxury fashion or ultra-heavy industrial gear (like conveyor belts, where nylon's tensile strength at a certain denier is the spec). Your situation might be different if you're dealing with medical-grade, flame-retardant, or food-service fabrics where regulations change the game.
One last thing I learned: don't assume the label tells the whole story. 'Coolmax' is a trademarked brand, not a generic term. Unscrupulous vendors might call a fabric 'cooling' or 'wicking' without it being genuine Coolmax technology. If the performance matters to you, ask for the Lycra Co. hang tag or certification. I've been burned by vanity labeling more than once. Check the care label for the fiber content—if it says '100% polyester' without a specific trademark, you're getting standard polyester at a premium price.
In the end, the right material is the one that fits your use case, budget, and your buyer's risk tolerance. I've learned to keep a swatch binder and document the fabric certifications for each order. That $60 in swatch samples saved me a $2,400 batch of failed polo shirts. It's a small cost for confidence in a purchase.