Aspen Aerogels, a Northborough, Mass.-based company that uses nanotech-processes to make insulation materials, has wrapped up a $37 million fourth round of funding. The round was led by Arcapita Ventures and joined by existing investors Lehman Brothers Venture Partners Reservoir Capital Group and RockPort Capital Partners.

Its patented aerogels, silica-based jelly-like materials, have a wide range of insulating applications in the apparel, building, transport and energy markets. The firm sells them in fabricated packages and easy-to-apply blankets that it claims are 2 – 8 times more effective than rival products.

Aerogels are extremely effective insulators — blocking most forms of thermal transfer and minimizing heat loss — which makes them invaluable in the construction of energy-efficient buildings. The same technology can be carried over to apparel and footwear, where it can easily be integrated into boots, jackets and other outdoor gear. Aspen’s aerogels are light, thin, waterproof and highly resistant under stress conditions.

The company has worked with major corporations like Samsung, Exxon Mobil, Boeing and British Gas. It had previously raised over $61 million. Serious Materials, a well-capitalized competitor in the energy-efficient construction sector, recently scooped up Alpen Windows, which sells windows with strong insulation properties.