Condensation Polymers: Comparing A & B

[yu]

Can someone please help me with this question? Thanx
Choose those statements that are correct about the following two condensation polymers:

(A) Prepared from ethylene glycol and terephthalic acid
and
(B) Prepared from glycerol (CH2OHCHOHCH2OH) and terephthalic acid

Both polymers have about the same molecular weight.
a) polymer (A) would be predicted to be weaker

b) polymer (A) would be predicted to be more flexible

c) Both polymers are attracted to each other by strong hydrogen bonds

d) polymer (A) would be predicted to have the higher melting point

 

[GCT]

The question is pretty standard.

a) not sure what they mean by "weaker," perhaps something in relevance to bullet proof glass. In this case, you need to determine if the polymer belongs to syndatic, atactic, etc...(should find it in your text).

b)I believe it is atatic polymers which exhibit such flexibility as rubber, although I'm not absolutely sure of this.

c)A polymer with alternating R groups would have the stronger hydrogen bond. This question is worded rather poorly, not very clear, since hydrogen bonds are strong to begin with.

d)both polymers have the same molecular weight and thus if there are any differences in this factor it is due to the effeciency of hydrogen bonding due to structure.

 

[ravenprp]

The correct statements are b) polymer (A) would be predicted to be more flexible and d) polymer (A) would be predicted to have the higher melting point.

Explanation: Polymer (A) is made up of longer chains compared to polymer (B) due to the presence of ethylene glycol, which has two reactive sites, compared to glycerol, which has three reactive sites. This results in longer chains and a higher molecular weight for polymer (A). Longer chains typically result in a more flexible polymer, as there are more opportunities for chain movement. Additionally, the longer chains in polymer (A) also result in a higher melting point, as there are more intermolecular interactions between the chains, making it more difficult for the chains to move and melt. Both polymers may have strong hydrogen bonds, as terephthalic acid has two carboxylic acid groups that can form hydrogen bonds, but polymer (A) would have a higher melting point due to the longer chains and more intermolecular interactions.