US firms Avantor Performance Materials and NuSil Technology have agreed to merge. Both are majority held by New York-based private equity fund New Mountain Capital which will remain as the major owner post-merger. The deal will create the global leader in ultra-high purity materials for the life sciences and advanced technology markets. Combined revenues will be above $700 million, and growing at 14% per year.

To be called Avantor, the new company will provide performance materials and solutions for the production and research needs of more than 6,500 customers across a variety of industries including biotechnology, pharmaceutical, medical device, diagnostics, aerospace & defense, and semi-conductor.

In addition, the combination of complementary technologies and advanced analytical capabilities will create a portfolio of more than 30,000 products which meet increasingly stringent standards across markets that are technology-driven and highly regulated.

New Mountain Capital’s managing director, Matt Holt, said the two companies had seen a positive transformation during its ownership, with strong organic growth and attractive margins. “The combined company will have strong positions across the drug lifecycle value chain including particular strengths in the bioprocessing and biomaterials segments, which we see as two highly attractive end markets that increasingly converge,” he said.

The investment firm bought into Avantor and Nusil in 2010 and 2011, respectively. Completion is expected in late September, subject to the usual closing conditions. Financial terms were not disclosed.