Quick Answer: BioCool PL by Alexium International is a 94% bio-based phase change material (PCM) for mattress ticking that absorbs body heat above a set temperature and releases it once you cool down, providing sustained cooling across the full sleep cycle. BioCool PL Plus achieves over 200 J/g thermal density with faster recrystallization than earlier PCM formulations. It is available in mattresses sold in Canada through brands that licence the technology.
In This Guide
Reading Time: 8 minutes
Phase change materials have been in mattress marketing for about a decade. They started appearing in memory foam toppers around 2014, and within a few years "gel-infused PCM" had become a standard feature claim across the mid-range mattress market. Most of those early implementations worked briefly, then stopped being effective as the material reached equilibrium with body temperature.
The BioCool PL technology from Alexium International, launched in 2025 and featured in new mattress models entering the market in 2026, addresses two specific limitations of earlier PCM: it resets faster between heat cycles, and it is made primarily from bio-based raw materials rather than petroleum-derived paraffin. Whether that makes a meaningful difference for your sleep is worth understanding clearly before paying a premium for it.
How Phase Change Materials Work in Mattresses
A phase change material absorbs heat without a corresponding rise in temperature while it transitions from solid to liquid state. The temperature at which this phase change occurs is engineered to match the target comfort zone, typically around 28-32 degrees Celsius for sleep applications.
The Physics of PCM Cooling
When your body temperature rises above the PCM's transition point, the material absorbs heat as it melts, drawing warmth away from the skin surface. This is called latent heat absorption, and it is the same principle that makes sweating effective: evaporation absorbs latent heat. The key metric for PCM performance is thermal density, measured in joules per gram (J/g). Higher J/g means the material can absorb more heat before it reaches full liquid state and stops absorbing. Early PCM formulations in mattresses often achieved 100-150 J/g. BioCool PL Plus targets over 200 J/g, which extends the duration and depth of cooling before the material needs to reset.
The reset process, called recrystallization, is where many PCM formulations fell short in earlier generations. Once the material fully melted, it needed to cool back down to solid state before it could absorb heat again. During that reset, it provided no cooling benefit. In a bedroom at 20 degrees Celsius, this reset happened reasonably quickly. In an Ontario summer bedroom at 25 degrees, the reset took much longer, meaning the PCM provided initial cooling but became ineffective for much of the sleep cycle.
BioCool PL: What Makes It Different
Alexium International's BioCool PL Plus (launched October 2025) introduces two improvements over their previous BioCool formulations:
BioCool PL Plus: Key Features
- Optimised nucleating profile: The crystallisation seed structure in the formulation has been redesigned to accelerate recrystallization, allowing the material to return to solid state faster between heat cycles. This means the PCM resets more frequently through the night rather than staying in liquid state once the initial cooling phase is complete.
- Over 200 J/g thermal density: Higher than most competing formulations, meaning more heat absorption capacity before saturation. In practice, this extends the initial cooling duration and helps manage the sustained low-level heat generation of a body at rest.
- 94% bio-based content: Registered under the USDA BioPreferred Program. The bio-based origin reduces reliance on petroleum-derived paraffin wax PCMs that dominated earlier generations. This matters for sustainability and, depending on the specific formulation, may affect biodegradability and recyclability of the ticking.
- Integration flexibility: Can be applied to mattress ticking fabrics, foam layers, toppers, and performance bedding. This allows mattress manufacturers to use it at the surface level (ticking) for immediate cooling sensation, or deeper in the comfort layer for sustained thermal management.
The USDA BioPreferred registration is verifiable. Alexium's BioCool PL is listed in the programme's database with 94% bio-based content, which aligns with the company's claims. The performance specifications (J/g, recrystallization rate) are proprietary and verified through manufacturer testing rather than independent third-party peer review, which is worth noting.
The Honest Limitations of PCM Technology
PCM is a useful technology in a well-designed mattress. It is not a substitute for good fundamental mattress construction.
PCM works best when it has a temperature differential to drive the phase change. In a very hot room, or when sleeping under a heavy duvet, the material may saturate quickly and the reset time increases. For significant night sweats or very warm sleeping environments, PCM provides some benefit but is not sufficient on its own.
What We Tell Hot Sleepers in Brantford
In our 37 years of fitting customers at Mattress Miracle, the pattern with cooling mattress technology is consistent: the people who get the most benefit from PCM-treated surfaces are those who sleep warm but not extremely hot, in reasonably climate-controlled bedrooms. The customers who are truly drenched in the night, or who are in a room that regularly hits 26-28 degrees in an Ontario summer, typically need a coil-based mattress with good airflow as the foundation, not just a PCM ticking treatment. PCM is a useful layer on top of that system. It is not the system.
There is also the question of durability. PCM microcapsules in mattress ticking are subject to mechanical stress over years of use and washing (for removable covers). The thermal density and reset performance of a PCM-treated surface in year 8 of use is not the same as year 1. This is rarely discussed in marketing materials.
Cooling Mattress Options for Hot Sleepers in Canada
Canadian hot sleepers in 2026 have several technology approaches to choose from, which are not mutually exclusive:
PCM-treated ticking: BioCool PL and similar products provide an immediate cooling sensation at the sleep surface and some buffering of temperature fluctuations. Best for moderately warm sleepers in reasonably cool bedrooms.
Natural fibre comfort layers: Wool, latex, and cotton are the longstanding alternatives to synthetic foam for thermal management. Wool wicks moisture and breathes. Latex's open-cell structure resists heat retention better than memory foam. These are passive thermal management strategies with decades of use history. Our Restonic Luxury Silk and Wool Queen ($1,395) combines these materials with a zoned pocket coil system for consistent temperature management through the night.
Pocket coil airflow: Individually wrapped coil systems allow air to circulate through the coil layer, preventing heat from concentrating at the sleep surface. The Restonic ComfortCare Queen ($1,125 with 1,222 coils) uses this approach. Heat generated by the body escapes downward through the coils rather than being trapped in solid foam.
Smart mattress cooling systems: Active cooling systems like Eight Sleep Pod 4 use water-circulated cooling pads. We reviewed these in our Eight Sleep review. They are more effective than passive PCM for significant heat management but significantly more expensive and require ongoing maintenance.
A Layered Approach to Sleep Temperature
The best results for hot sleepers come from layering complementary strategies rather than relying on any single technology.
Building a Cooler Sleep System
- Mattress foundation: Pocket coil system with natural fibre or open-cell latex comfort layers. Avoids solid memory foam. (Restonic ComfortCare or Revive Reflections ET).
- Ticking technology: PCM-treated ticking for surface cooling sensation. BioCool PL or similar. Increasingly standard on mid-to-premium mattresses.
- Mattress protector: Cotton terry or moisture-wicking protector, not vinyl-backed. A waterproof protector with a non-breathable backing negates any ticking cooling benefit. Ask us which protectors we recommend at Mattress Miracle.
- Bedding: Percale or bamboo cotton sheets. Avoid microfibre. Keep a single lighter blanket rather than a heavy duvet for temperature flexibility through the night.
- Room temperature: Target 17-19 degrees Celsius (Canadian Sleep Society recommendation). A fan with indirect airflow reduces the ambient temperature that determines PCM reset effectiveness.
- Sleepwear: Moisture-wicking fabric if you sweat significantly. See our cooling sleepwear guide.
Dorothy, our sleep specialist, sometimes puts it this way: "Cooling technology in a mattress is like sunscreen on a hot day. It helps, but it does not replace the shade." The mattress construction provides the shade. The PCM provides the sunscreen. You need both to be genuinely comfortable as a hot sleeper in an Ontario summer.
If you are in Brantford or the surrounding region, come into Mattress Miracle at 441 1/2 West Street and lie on a few options. We can show you the difference in feel between a coil-based mattress and a foam mattress, and help you understand which combination of materials matches your sleeping temperature. Call (519) 770-0001 to check current stock.
Frequently Asked Questions
What is BioCool PL and how is it different from regular phase change material?
BioCool PL by Alexium International is a 94% bio-based phase change material with over 200 J/g thermal density and an optimised recrystallization profile that allows it to reset between heat cycles faster than earlier PCM formulations. Earlier PCMs were typically petroleum-derived paraffin with lower thermal density, meaning they saturated sooner and took longer to reset. BioCool PL is registered under the USDA BioPreferred Program.
Does PCM in a mattress actually work for hot sleepers?
Yes, with qualifications. PCM provides measurable initial cooling and some buffering of temperature fluctuations during sleep. It works best for moderately warm sleepers in bedrooms below 23 degrees Celsius. For severe night sweats or very hot bedrooms, PCM alone is insufficient and benefits from being combined with a coil-based mattress structure that allows airflow and natural fibre comfort layers that manage moisture.
Are PCM mattresses available in Canada?
Yes. Several mattress brands in Canada use PCM-treated ticking, including mattresses available through major retailers. BioCool PL specifically is licenced to mattress manufacturers who may sell in Canada. When shopping, ask specifically about the PCM technology used and whether it is surface-applied or foam-integrated, as performance differs between applications.
What mattresses at Mattress Miracle are best for hot sleepers?
Our Restonic ComfortCare Queen ($1,125, 1,222 individually wrapped coils) and Revive Reflections ET ($1,395, flippable dual-sided) are both consistent recommendations for hot sleepers. The coil systems allow heat to escape rather than concentrating at the surface. Our Luxury Silk and Wool Queen ($1,395) adds natural fibre thermal management for those who prefer natural materials throughout. Come into our Brantford showroom or call (519) 770-0001 to discuss which is right for you.
How do I keep my bedroom cool enough for PCM to work properly in an Ontario summer?
Target a bedroom temperature of 17-19 degrees Celsius, as recommended by the Canadian Sleep Society. In summer, this typically requires either air conditioning or a fan with good whole-house cross-ventilation. Positioning a fan to draw cool air in from a north-facing window overnight, then blocking that window during the day, is a low-cost approach for homes without AC. A higher-performing PCM like BioCool PL resets faster in cooler ambient conditions, so room temperature management directly affects how well the mattress technology works.
Sources
- Alexium International. (October 2025). Alexium Launches BioCool PL Bio-Based PCM Technology. Bedtimes Magazine. bedtimesmagazine.com
- Alexium International. (2025). BioCool: Microencapsulated PCM products for bedding applications. alexiuminternational.com/biocool
- Okamoto-Mizuno, K., & Mizuno, K. (2012). Effects of thermal environment on sleep and circadian rhythm. Journal of Physiological Anthropology, 31(1), 14. doi.org/10.1186/1880-6805-31-14
- Krauchi, K. (2007). The thermophysiological cascade leading to sleep initiation in relation to phase of entrainment. Sleep Medicine Reviews, 11(6), 439-451. doi.org/10.1016/j.smrv.2007.07.001
- Shin, M., et al. (2016). The effects of fabric for sleepwear and bedding on sleep at ambient temperatures of 17°C and 22°C. Nature and Science of Sleep, 8, 121-131. doi.org/10.2147/NSS.S100271
- Jacobson, B.H., et al. (2008). Grouped comparisons of sleep quality for new and personal bedding systems. Journal of Chiropractic Medicine, 7(4), 139-144. doi.org/10.1016/j.jcme.2008.09.002
Visit Our Brantford Showroom
Mattress Miracle
441 1/2 West Street, Brantford
Phone: (519) 770-0001
Hours: Mon-Wed 10-6, Thu-Fri 10-7, Sat 10-5, Sun 12-4
If heat is keeping you awake, come and lie on our coil-based options. The difference between a pocket coil mattress and a dense foam mattress in terms of thermal feel is something you have to experience to appreciate. We have been helping hot sleepers in Brantford find the right match since 1987.