Partners: Alejandra Garcia
Date: 2 December 2011
TA: Mengbin Chen
Skill Building Exercise #2
Answer the following questions:
1. What does it mean when a polymer is crosslinked?
Crosslinked is one manner in which monomers link together. In this method, separate polymer chains are connected via bonds between the individual polymer chains. 2. We discussed how polymer linking and structure contribute to its properties. How would you expect the density, elasticity, and rigidity of a polymer that is branched to compare to one that is linear? I would expect the density of the linear polymer to be much higher than the density of the branched polymer, which I would expect to have low density. The branched structure, though, would be more elastic than the linear structure. The linear polymer would be expected to have more rigidity than the branched structure.
3. Consider the following polymer:
a. Identify and draw the chemical formula of the monomer from which this polymer is made of. Clearly explain the criteria you used to identify the monomer. State how many carbons, oxygens, and hydrogens can be found in one monomer of this polymer. This is the monomer. (C2H4O)
In this monomer there are two carbons, four hydrogens, and one oxygen. I identified this as the monomer by looking for the repeating component of the polymer. b. This polymer is hydrophilic. Give a plausible reason for this behavior. Your explanation should be based on the molecular structure of the polymer, the molecular structure of water, and the interactions between molecules of these two substances. You should use terms such as polarity, polar bond, charge, interactions, attractions, repulsions or hydrogen bonds. However, you should use only those terms that apply to this situation. The polymer is surrounded by hydrogens via hydrogen bonds between the hydrogens and the carbons. This is a polar bond, resulting in hydrogen being relatively...