What are polymers, monomers and macromolecules?
Polymers are macromolecules composed of one or more chemical units (known as monomers) that are repeated along the entire chain. Imagine, for example, a necklace of pearls: each of the pearls would be a monomer while the entire necklace is what is known as a polymer.
As you can imagine, polymers to which we give so different utilities have very different characteristics and some of them are marked by their origin. Here we explain what natural polymers are and what differentiates them from artificial polymers:
Monomer and polymer examples
A polymer is a chain of repeating units or monomers (from the Greek mono=one, unit) that are joined and repeated to form a macro-molecule (tens of millions of repeating units) or polymer.
The most common atoms forming plastic resins are 3: carbon, whose chemical symbol is C with 4 bonds, Hydrogen, whose chemical symbol is H and has one bond and Oxygen, whose chemical symbol is O with 2 bonds.
Carbon is possibly the most important atom in the formation of plastic resins since it forms what is known as the backbone, taking 2 bonds to join one carbon to another and leaving 2 bonds to join other atoms.
In the following example we can see the ethylene molecule (CH2=CH2), these molecules when subjected to pressure and temperature inside a reactor, will unite forming the polyethylene polymer, this process is known as polymerization.
Natural gas is a source of raw material in the production of polymers, from which ethylene is released to form polypropylene and methane is transformed into formaldehyde, from which phenolic resins are made.
What is the difference between a monomer and a brainly polymer?
They are those coming directly from the vegetable or animal kingdom, such as silk, wool, cotton, cellulose, starch, proteins, natural rubber (latex or rubber), nucleic acids, such as DNA, among others. There are natural polymers of great commercial significance:
They are those transformed or “created” by man. These include all plastics, the best known in everyday life being nylon, polystyrene, polyvinyl chloride (PVC) and polyethylene. The wide variety of physical and chemical properties of these compounds allows them to be used in construction, packaging, the automotive industry, aeronautics, electronics, agriculture and medicine.
Styrene Butadiene Rubber, better known as SBR, is a copolymer (polymer formed by the polymerization of a mixture of two or more monomers) of styrene and 1,3-butadiene. It is the most widely used synthetic rubber worldwide.
Monomer oligomer and polymer
Polymerization is a chemical reaction by which the reactants, monomers (compounds of low molecular weight), form chemical bonds with each other to give rise to a molecule of high molecular weight (macromolecule), whether it has a linear chain or a three-dimensional structure, called a polymer.
As previously mentioned, a polymerization by addition occurs when the monomer molecule becomes part of the polymer without loss of atoms, i.e., the chemical composition of the resulting chain is equal to the sum of the chemical compositions of the monomers that make it up. Therefore, no by-products are generated during addition polymerization.
An example to illustrate this point could be the synthesis of polyethylene. When ethylene is polymerized to obtain polyethylene (PE), each atom of the ethylene molecule is transformed into part of the polymer. The monomer is added to the polymer as a whole.
Let us look at an example to illustrate this point. In the production of nylon 6,6 (polyamide) from adipoyl chloride and hexamethylene diamine, each chlorine atom of the adipoyl chloride together with one of the hydrogen atoms of the amine is expelled as gaseous HCl (hydrogen chloride).