Polypropylene (PP), a thermoplastic polymer, is renowned for its unique blend of properties, making it highly versatile in various applications. Key characteristics include its resistance to chemical solvents, bases, and acids, contributing to its durability in chemically demanding situations. Additionally, PP has a high melting point (approximately 160°C), enabling its use in scenarios requiring thermal resistance. Its low density translates to lightweight products without sacrificing strength or rigidity, making it ideal for packaging, automotive parts, textiles, and consumer goods. Another notable feature is its fatigue resistance, essential in the manufacture of living hinges, such as those on flip-top bottles. Polypropylene can also be easily modifiable with additives to enhance colors, flexural strength, or UV resistance, increasing its utility across industries. However, it is susceptible to UV degradation and can become brittle in cold temperatures, limitations that can be partly mitigated through material engineering and treatments.

Titanium has a density of 4.506 grams per cubic centimeter. while aluminum has a density of 2.70 grams per cubic centimeter.

To keep yarn from frizzing, start by choosing yarns with tightly twisted fibers or those made from materials less prone to frizz, such as cotton or synthetic blends. Store your yarn in a cool, dry place, away from direct sunlight and moisture, to prevent deterioration. When working with yarn, maintain a gentle tension to avoid overstretching the fibers, which can lead to frizzing. Use the appropriate needle or hook size to minimize stress on the yarn. Avoid dragging the yarn across rough surfaces. If frizzing occurs, lightly mist the yarn with water and smooth it with your fingers or comb it gently with a wide-tooth comb. For completed projects, wash according to the yarn’s care instructions, and lay flat to dry. Consider using a fabric softener or a specialized yarn conditioner in the wash to help keep fibers smooth.