Microcapsules that can be incorporated into the walls of data centers could help manage server temperature in the event of a power or cooling outage.

Chemistry firm Alexium International Group has made its microencapsulated phase change material (mPCM) solutions available to US data center developers as “a passive thermal buffer built into the facility itself.”

Originally developed by chemical company BASF, the mPCMs transform ordinary wallboard, plaster, aerated concrete, ceiling cassettes, and architectural coatings into latent thermal mass, Alexium said.

Each microcapsule holds a proprietary core inside a cross-linked shell, small enough to mix into the building material without changing how it is installed. When room air temperature climbs past the mPCM's melt point, the core melts and absorbs heat; when the space cools, it re-solidifies and releases it.

Alexium is not marketing this as a data center cooling solution. After all, it is not capable of removing heat, simply storing it. But it says its mPCM-based coatings could be a useful addition to a data hall in the event of a cooling system failure, absorbing additional heat generated by servers before backup systems kick in and repairs can be carried out.

The company manufactures wall coatings containing the microcapsules, with three different options for capsule melting point, to suit different scenarios. It acquired the technology in December 2025, when it purchased Microtek Laboratories.

It says 15mm board loaded with three kg/sqm of its capsules can offer the same heat-storage capacity of roughly 9cm of concrete. The capsules have apparently been tested through 10,000 thermal cycles, equivalent to about 30 years of daily use, with no notable change in performance.

"The data center industry is asking a building-materials question — how can active temperature management solutions help minimize peak energy demand during extreme daily temperature swings," said Billy Blackburn, CEO and managing director of Alexium.

"Alexium’s suite of PCMs are designed to meet these challenges and now vertically integrated for global manufacturing & distribution. We're putting it in front of the developers, engineers and manufacturers who are building the data center & AI campuses of the next decade."

"Our microencapsulation platform is what lets us tune the melt point to the room — a 26°C (78.8°F) grade for a data hall envelope, a custom point for a chilled-water loop," said Randall Lane, Alexium COO. "That's the conversation we want to have with engineers and OEMs now, while these facilities are still on the drawing board."