Polybutylene is a type of plastic commonly used in plumbing systems and piping. It is known for its flexibility, lightweight nature, and resistance to corrosion, making it a popular choice for water supply lines in homes and buildings. However, it has faced criticism due to concerns about its durability and potential for leaks over time. In the 1990s, issues arose with polybutylene pipes, leading to lawsuits and recalls. Many homeowners experienced failures in their plumbing systems, prompting a shift towards more reliable materials like PVC and PEX. Today, polybutylene is less commonly used in new construction due to these concerns.