Question

Polystyrene can be made more rigid by copolymerizing styrene with divinylbenzene: How does the divinylbenzene make the copolymer more rigid?

Short answer

The divinylbenzene makes the copolymer more rigid by forming cross-links between the polymer chains due to the presence of its two vinyl groups. This creates a more interconnected and rigid network structure in the copolymer, resulting in increased rigidity and durability compared to polystyrene alone.

Step-by-step solution

Understand copolymerization

Copolymerization is a process where two or more different monomers (small molecules) are chemically combined to form a polymer (a large molecule composed of repeating units). In this case, we want to understand the copolymerization of styrene and divinylbenzene, and how this process makes the resultant copolymer more rigid.

Analyze the structure of styrene and divinylbenzene

Styrene is a monomer with the chemical formula C8H8. Its structure consists of a benzene ring with a vinyl group (CH=CH2) attached to it. Divinylbenzene, on the other hand, is similar to styrene but has two vinyl groups attached to the benzene ring, with the formula C10H10.

Understand the impact of divinylbenzene on the copolymer

When styrene and divinylbenzene are copolymerized, the resultant copolymer has a more complex structure than that of polystyrene alone. The presence of two vinyl groups in the divinylbenzene molecule allows it to form cross-links between the polymer chains, creating a more interconnected and rigid network structure in the copolymer.

Conclusion

The addition of divinylbenzene to styrene during the copolymerization process results in the formation of a more rigid copolymer. This is because the divinylbenzene molecules can form cross-links between the polymer chains, allowing for a more interconnected and rigid network structure in the copolymer. This increased rigidity can be beneficial in various applications, such as in the production of more rigid and durable plastic materials.