What are the challenges of achieving airtight seals in hollow polypropylene sculptures?

Creating airtight seals in hollow polypropylene sculptures presents several unique challenges. Polypropylene, while lightweight and durable, has a low surface energy, making it difficult for adhesives to bond effectively. The material's tendency to warp under heat complicates welding processes, often leading to weak seams or leaks. Additionally, hollow structures require precise joint alignment to prevent gaps, and internal stresses from molding can cause micro-fractures over time. To address these issues, advanced techniques like hot gas welding or laser welding are often employed, but achieving a perfect seal remains a delicate balance of material science and craftsmanship. Understanding these challenges is crucial for artists and engineers working with polypropylene in sculptural applications.