PVA PVA is commonly known for its ability to be dissolved in water and is often used as a support material for complex prints. Polypropylene Polypropylene is great for high-cycle, low strength applications due to its fatigue resistance, semi-flexible, and lightweight characteristics. Nylon Nylon is a tough and semi-flexible material that offers high impact and abrasion resistance. It is an ideal choice for printing durable parts. Flexible Flexible filaments, commonly referred to as TPE or TPU, are known for their elasticity allowing the material to easily stretch and bend.