Chemicals are fundamental to the production of polymers, which are large molecules made through chemical reactions involving monomers (small molecules). The key processes involve polymerization, modification, and cross-linking, utilizing various chemicals to control the structure and properties of the resulting polymers. Monomers are the basic building blocks such as styrene, butadiene and others which serve as the raw material. These monomers contain reactive functional groups (like double bonds, hydroxyl groups, etc.) that enable polymerization. Initiators are typically chemicals such as peroxides which initiate the polymerization process. They generate free radicals, cations, or anions that start chain reactions. Different monomers are combined to create copolymers with tailored properties. Flame retardants are also used to make Flame retardant polymers.