J. Crew, the preppy retailer that has been struggling to find its footing in recent years, may spin off its Madewell brand by the end of 2019.

The company said on Thursday that it was exploring a potential initial public offering for Madewell, which could be completed in the second half of 2019, as it looks to raise much-needed capital. J. Crew, which has not had a leader since November, also said that Michael J. Nicholson, its president and chief operating officer, would be its interim chief executive.

A potential Madewell I.P.O. could bring in capital to help pay off debt that J. Crew is set to repay in 2021 and improve the retailer’s overall balance sheet. The company views a spinoff as “giving us an improved platform to support J. Crew’s turnaround and allowing Madewell to achieve its full potential over the long term,” Mr. Nicholson said in the statement.

J. Crew declined to comment beyond its statement.

The announcement puts a spotlight on J. Crew’s challenges with merchandise and leadership in the past few years and the divergent fortunes of its newer, though much smaller, Madewell brand. J. Crew, known for its classic, colorful workwear, kicked off the decade as a favorite of Michelle Obama. It was taken private in 2011 in a $3 billion deal led by TPG Capital and Leonard Green & Partners. But the brand’s sales started to falter in 2015 as it made fashion missteps and began to lose favor with many of its core consumers, who questioned the quality and fit of its apparel.