Lei Jun's Watermelon Drop Video Goes Viral, Showcasing Breakthrough Polyurea Coating Technology

2025-03-31 13:52:30

A recent video of Xiaomi CEO Lei Jun dropping a watermelon from the sixth floor has taken the internet by storm.

In the footage, the watermelon bounces multiple times upon impact but remains completely intact. The secret behind this remarkable feat is a bulletproof coating applied to the watermelon's surface. This coating boasts puncture resistance, tear resistance, and extreme durability—the same technology now protecting the battery pack of Xiaomi's SU7 Ultra electric vehicle, creating an impenetrable safety barrier for its battery cells.

From Obscurity to Spotlight: The Rise of Polyurea Coatings

This groundbreaking application has thrust polyurea materials into the limelight. Originally a niche material, polyurea is gaining widespread attention for its exceptional properties and expanding applications across multiple industries.

Polyurea Coatings: A Laboratory-Born Revolution

Polyurea's origins trace back to scientists' relentless refinement of polyurethane materials. In 1989, chemist Dudley J. Primeaux II and his team at Texaco (now Huntsman) developed spray polyurea elastomer technology, publishing the first research paper on the subject. This innovation used a rapid reaction between amine-terminated polyethers and isocyanates to achieve catalyst-free curing, solving traditional polyurethane coatings' humidity sensitivity and bubbling issues.

The breakthrough offered three key advantages:

1. Instant curing (5-second gelation, load-bearing in 1 minute—10x faster than conventional coatings)

2. Environmental friendliness (zero VOC emissions without catalysts)

3. Performance leap (16MPa tensile strength, 5-10x the wear resistance of rubber, and stability from -40°C to 150°C)

Commercialized in North America in 1991, polyurea technology soon spread globally through the Polyurea Development Association (PDA), establishing standards that propelled its use in construction, transportation, energy, and beyond.

China's Polyurea Industry: From Technology Import to Independent Innovation

China's polyurea development has progressed through three critical phases:

1. Technology Introduction (1995-2002)

• Qingdao Marine Chemical Research Institute pioneered domestic research, importing U.S. equipment in 1997 and launching China's first commercial polyurea product in 1998.

2. Rapid Expansion (2002-2009)

• High-speed rail construction drove demand, with the Beijing-Tianjin line using 2,000 tons of polyurea waterproofing. However, quality issues from low-cost bidding temporarily damaged the material's reputation until stricter standards were enforced.

3. Standardization & Innovation (2010-Present)

• National standards (GB/T23446-2009, JG/T200-2010) improved quality control. Environmental policies and infrastructure growth further expanded applications in construction, transportation, and water conservancy.

Polyurea Coatings: A Cross-Industry Game Changer

Initially used for military armor and industrial corrosion protection, polyurea now dominates diverse sectors:

• Construction: Seamless, instant-curing waterproofing for roofs, basements, and utility tunnels

• Transportation: Critical protection for mega-projects like the Hong Kong-Zhuhai-Macao Bridge and undersea tunnels

• Automotive: Xiaomi SU7 Ultra's battery armor demonstrates 10x improvements in tear/puncture resistance versus PVC coatings

Green Polyurea: Pioneering Sustainability

Aligned with global decarbonization goals, manufacturers are developing bio-based and waterborne polyurea formulas to reduce environmental impact. Early adopters of these eco-friendly technologies will lead the next wave of industry growth.

Lei Jun's watermelon experiment not only showcases polyurea's incredible properties but also heralds its expanding role in carbon-neutral manufacturing. As innovation continues, this versatile material will drive quality advancements across countless applications.