Selecting the correct polymer is critical for structural integrity. For standard indoor masonry, Polyamide (Nylon 6 or 66) is the industry gold standard due to its high tensile strength, elasticity, and resistance to aging. For outdoor or humid environments, ensure the material is UV-stabilized and consider Polyethylene (PE) or Polypropylene (PP) for better moisture resistance, though they offer lower load-bearing capacities than Nylon. Always verify that the material is virgin grade rather than recycled to prevent brittleness.