Polymers and Plastics

Monomers are the smallest repeating units that join together through polymerization to form large polymer chains. For example, ethene monomers join to form polythene. 'Repeating unit' refers to the unit within the polymer chain, not the starting molecule, and 'dimer' means only two units bonded together.

Melamine is a thermosetting plastic that exhibits excellent fire resistance due to its strong cross-linked molecular structure. Teflon (PTFE) has high heat resistance but is not specifically classified as fireproof, while polythene and polystyrene are thermoplastics that can melt and burn.

Melamine plastic is used in firefighter uniforms specifically because of its fire resistance property. It does not burn easily and can withstand high temperatures. While melamine is lightweight and has good tensile strength, the critical property for fire safety applications is its resistance to catching fire.

Rayon is smooth, cool, and highly absorbent, making it comfortable to wear. However, unlike natural fibres such as wool or cotton, rayon does not insulate body heat well - it can feel cold to the touch. This lack of thermal insulation is the property that rayon does not possess compared to many other fibres.

Polythene (polyethylene) is formed by the polymerization of ethene (ethylene) monomers. When ethene molecules undergo addition polymerization, they link together to form the long chains that make up polythene. Propene would give polypropylene, ethyne is a different alkyne, and ethane is a saturated hydrocarbon.

Nylon-6,6 is synthesized through condensation polymerization of adipic acid (a dicarboxylic acid) and hexamethylene diamine (a diamine). Formaldehyde and phenol produce bakelite, while acrylonitrile is used for acrylic fibres. The correct monomers for nylon specifically are adipic acid and hexamethylene diamine.

Ballistic nylon is a thick, durable synthetic nylon fabric used for protection, but it is not classified as a standard chemical monomer-based nylon designation like Nylon 6,6, Nylon 6, or Nylon 6,12. Standard nylons are named based on the number of carbon atoms in their monomer chains.

Duroplast is a composite thermosetting plastic, a close relative of formica and bakelite.  Bakelite is a thermosetting phenol formaldehyde resin, formed from an elemination reaction of phenol with formaldehyde.

Carbowax refers to the trademark for polyethylene glycol.

PET is a form of polyster and is used for making bottles, utensils, films, wires and many other useful products.

Bakelite is a poor conductor of heat and electricity. It is used for making electrical switches handles of various utensils etc.

Nylon is a strong fibre, polyester prevents loss of body heat during winters. Melamine resists fire and bakelite is a poor conductor of heat and electricity.

Terylene is a popular polyester.

Bakelite is used for making electrical switches.

Cassava is a plant product used to make biodegradable plastic. Tapioca is a starch extracted from cassava.  In India, the term tapioca is used to represent the root of the plant (cassava), rather than the starch. Tapioca root can also be used to manufacture biodegradable plastic bags.