What Is a Macromolecule?
Macromolecules, also known as polymers, are large organic molecules with a molecular weight of over 10,000, primarily composed of carbon along with elements like oxygen, hydrogen, and nitrogen. They are categorized into synthetic macromolecules and biopolymers.
Since their conceptualization in 1917, macromolecules have been central to advancements in materials science, leading to a variety of applications, especially during World War II.
Uses of Macromolecules
Macromolecules serve as the foundation for a wide range of products, from synthetic plastics and fibers to biological DNA and proteins. They are critical in manufacturing, medical materials, and everyday products due to their versatile properties like strength, heat resistance, and transparency.
Principles of Macromolecules
Macromolecules are formed by polymerization, where small molecules (monomers) bond together. This process can vary, resulting in diverse structures and properties among macromolecules, depending on the monomers and polymerization methods used.
1. Chain Polymerization
A process where monomers link into long chains, categorized by the type of initiating active species into radical, anionic, and cationic polymerization.
2. Sequential Polymerization
Monomers with multiple functional groups react to form intermolecular bonds, leading to chain elongation. This includes polycondensation, polyaddition, and addition-condensation reactions.
Types of Macromolecules
Macromolecules vary widely in properties based on their monomer composition and molecular weight. For example:
1. Chain Polymerization
Examples include polyethylene (PE), polypropylene (PP), and polystyrene (PS).
2. Sequential Polymerization
Examples include polyethylene terephthalate (PET) and polyamide (PA).