Question

Which of the following is an example of a thermoplastic polymer?
A.Bakelite
B.Polysiloxanes
C.Sealing wax
D.All of the above

Answer 1

We know that plastic is a polymer. When a plastic is heated, it melts and is given a particular shape when it cools. The plastics which can undergo this process are known as thermoplastics. On heating, thermoplastics soften and harden when cooled.

Complete answer:
With regard to the behaviour they show at high temperatures, polymers can be classified as either thermoplastics or thermosetting plastics. Thermoplastic polymers are those which have a linear and branched structure. Thermoplastics on exposure to heat soften and when cooled, they harden. In contrast, thermosetting polymers once they hardened, do not soften upon heating. They have a cross-linked and network structure.
Based on this information, we can conclude that of the following plastic polymers, the thermoplastic is sealing wax.

Thus, the correct answer is C.

Additional information:
Many thermoplastic polymers are reinforced with fibers to improve their physical properties, mainly heat deflection temperature. The most commonly used reinforcing material is glass fibre. The use of aramid reinforcement improves the wear abrasion resistance of the thermoplastic polymer.
Thermoplastic polymers have been used widely for a long time. Recently a newer high temperature or high performance thermoplastic has been introduced. The early thermoplastic polymers were made up of predominantly aliphatic carbon backbones in which the flexible carbon chains could be extended and rotated into many configurations easily.

Note:
Thermoplastics as compared to thermosetting polymers, absorb much less moisture with a less consequential reduction in the mechanical properties at high temperatures. Thermoplastics are much tougher and therefore have a better resistance to impact and inter- laminar strength.