Plexiglass is neither polyethylene nor polypropylene. It is actually a brand name commonly used to refer to acrylic, which is a type of plastic officially known as polymethyl methacrylate (PMMA). While both polyethylene and polypropylene are polymers used in a wide range of applications due to their versatility and durability, PMMA offers unique properties like superior clarity, weather resistance, and excellent light transmission, making it a popular choice for applications requiring clear visibility and durability such as windows, shields, and various design projects.

Polypropylene, a versatile thermoplastic polymer widely used in various applications, is naturally translucent when unmodified. However, it can be produced or colored in a broad spectrum of colors for specific uses, ranging from consumer products to industrial applications. Manufacturers often incorporate additives or pigments to achieve desired colors and properties, such as enhanced UV resistance. This capability to be tinted in any color makes polypropylene popular for a wide array of products, including packaging, automotive components, textiles, and household goods. Its color adaptability, combined with other characteristics like lightweight, resistance to chemicals, and durability, underscores its widespread utility in many sectors.

Low Density Polyethylene (LDPE) is manufactured through the polymerization of ethylene, a gas derived from oil and natural gas, using high-pressure processes at temperatures between 100 and 300°C. In this process, initiated by free radicals, ethylene gas molecules are subjected to high pressure and temperatures, causing them to react and form long polymer chains. The resulting polymer is cooled, cut into granules, and can be further processed into films, containers, and other products. LDPE is characterized by its flexibility, moisture resistance, and transparency, making it ideal for packaging, agricultural films, and electrical insulation.