Question

Thermoplastics have bonds which [Select] are strongest between the chains are strongest along the length of the chains are strongest in the cross links are strongest between the bulky side groups

Answer 1

Feature/Property Thermoplastics Thermosets Molecular structure Linear polymer: weak molecular bonds in a straight- chain formation Network polymers: high level of crosslinking with strong chemical molecular bonds

Though Thermoplastics have weak molecular bonds in a straight chain but are strongest in the cross links when made into thermosets.

In the last lesson on ceramics, we saw that one way to classify ceramics is by their uses (refractories, glass, clay products, abrasives, etc.). Other possible classification categories might include crystal structure and whether they are crystalline or non-crystalline. For polymers, one useful classification is whether they are thermoplastic or thermosetting polymers. As you read in the last reading assignment, thermoplastics soften when heated and harden when cooled. This is totally reversible and repeatable. Most linear polymers and branched structure polymers with flexible chains are thermoplastics. This is in contrast to thermosetting polymers, which do not soften when heated due to strong covalent crosslinks. Thermoset polymers are generally harder and stronger than thermoplastics and have better dimensional stability.