Although the 17 investors in the latest $15m round were undisclosed, in October 2010 BASF Venture Capital, the corporate venturing unit of Germany-based chemical conglomerate BASF, led a $21.5m investment in Aspen Aerogels as a new investor.

Aspen Aerogels, US-based insulation materials company, has raised 60% of a planned $25m round ahead of its flotation, according to a regulatory filing first seen by news provider Mass High Tech.

In June, just after raising $30m in a similar debt, options and warrants round of financing, Aspen said it wanted to raise $115m in its initial public offering co-managed by investment banks Goldman Sachs and Morgan Stanley.

Although the 17 investors in the latest $15m round were…