Recycling
Thermoplastics are easily recyclable, compared to thermosets, because the polymer chain does not degrade when melted down. This is because the weaker interactions between polymer chains break down at much lower temperatures than the chemical bonds between monomers. This allows thermoplastics to be recycled indefinitely until the polymers are broken down to the point that the material loses structural integrity.
Brick and concrete are good analogies when comparing the properties of thermosets and thermoplastics. A thermoplastic is made of strong polymers, like bricks, with weak forces holding them together, like mortar. A thermoset is made of strong polymers that bind together and form one molecule, similar to concrete. Recycling or reforming a thermoplastic is like chipping out the mortar and re-laying the bricks; in contrast, a thermoset, like concrete, can never be broken down and reformed with the same strength. However, if individual bricks are damaged, relaying them will not restore the strength of the unbroken bricks, just as remelting a degraded thermoplastic will not restore damaged polymers.
In real-world recycling, thermoplastics have a limit recyclable lifespan due to degradation of the polymers and contamination during the recycling process. Contaminants can be inert materials, which act as fillers, or they can be other plastics, which alters the physical properties of the resulting material.
Read more about this topic: Thermoplastic
Famous quotes containing the word recycling:
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