Consider the polymer polybutadiene.
(a) Will linear polybutadiene or branched polybutadiene have a higher molar volume?
(b) Will linear polybutadiene or branched polybutadiene have a higher glass transition temperature?
(c) Will linear polybutadiene or branched polybutadiene have a lower fluidity at a given temperature?
a)Branched polybutadiene
b)Branched polybutadiene
c)Linear polybutadiene
tnxs
To determine which form of polybutadiene (linear or branched) will have a higher molar volume, glass transition temperature, and lower fluidity at a given temperature, we need to consider the molecular structure and properties of both forms.
(a) Molar volume: The molar volume is influenced by the size and shape of the polymer molecules. Branched polybutadiene has a more compact structure with branches that reduce the space occupied by the polymer chains. On the other hand, linear polybutadiene has a more extended and less densely packed structure. As a result, branched polybutadiene will have a higher molar volume compared to linear polybutadiene.
(b) Glass transition temperature: The glass transition temperature is the temperature at which an amorphous polymer transitions from a rigid, glassy state to a soft, rubbery state. The presence of branches in polybutadiene introduces additional molecular freedom and flexibility, which lowers the glass transition temperature. Therefore, branched polybutadiene will have a higher glass transition temperature compared to linear polybutadiene.
(c) Fluidity: Fluidity refers to the ability of a polymer to flow or move at a given temperature. It is influenced by factors such as chain mobility and intermolecular interactions. Generally, polymers with more flexible and movable chains exhibit higher fluidity. The presence of branches in polybutadiene increases chain mobility and reduces intermolecular interactions, resulting in higher fluidity. Therefore, branched polybutadiene will have lower fluidity at a given temperature compared to linear polybutadiene.
Overall, the relationship between linear and branched polybutadiene can be summarized as follows:
- Branched polybutadiene has a higher molar volume and lower fluidity compared to linear polybutadiene.
- Linear polybutadiene has a higher glass transition temperature compared to branched polybutadiene.