After graduating from high school, Sun Aixiang spent nearly two decades selling plastics and adhesive products such as glue and tape. A shrewd decision to establish a materials company with his brother-in-law Zhao Jianping in 2003 has now made both men billionaires on paper, following Shenzhen HFC’s blockbuster listing and a first-day share price surge of as much as 719%.

Sun, the company’s 58-year-old chairman, has amassed an estimated fortune of $1.7 billion from his stake in the company, following its listing on the Shenzhen Stock Exchange, according to Forbes estimates. Zhao, a 63-year-old company director, is worth an estimated $1.3 billion based on his stake.

Shenzhen HFC raised 1.4 billion yuan ($214.4 million) in its initial public offering by selling 18.7 million shares at 76.9 yuan apiece. The company, which is backed by investors including Huawei’s venture capital arm, Hubble Investment, plans to use most of the proceeds to build research centers in China. Strategic investors in the IPO included optical transceiver maker Eoptolink and Alibaba’s cloud computing arm, according to a stock exchange filing. Shenzhen HFC didn’t respond to a request for comment.

The stock’s rally follows a familiar pattern in China. Investors have been eager to buy shares in newly listed companies considered important to China’s drive for technological self-reliance, in anticipation of first-day price surges.

Sun’s company specializes in heat management materials such as thermal pads and thermally conductive gels. These materials are widely used with AI chips and in optical modules and data center equipment to transfer and dissipate heat. Shenzhen HFC also makes electromagnetic-interference shielding and wave-absorbing materials that protect electronic equipment from disruptive electromagnetic interference.

As companies around the world build more data centers, Shenzhen HFC’s revenue surged 114% to 706.7 million yuan in 2025, according to its prospectus. Net income nearly quadrupled from its 2024 level, reaching 269 million yuan. The company, which generates about two-thirds of its revenue overseas, counts billionaire Terry Gou’s Hon Hai Precision Industry, better known as Foxconn, among its largest customers.

Shenzhen HFC has cautioned, however, that it may not be able to sustain such rapid growth. Growth may slow because of global economic uncertainty and customers’ efforts to diversify their supply chains, according to its prospectus. The company expects revenue for the first nine months of 2026 to rise by 31.1% to 39.3%, reaching between 640 million yuan and 680 million yuan. Net income is expected to increase by 28.7% to 40.7%, reaching between 245 million yuan and 268 million yuan over the same period, according to the prospectus.