This topic contains a solution. Click here to go to the answer

Author Question: What are the key polymeric structural features common to most elastomeric materials? What will be ... (Read 68 times)

chads108

  • Hero Member
  • *****
  • Posts: 507
What are the key polymeric structural features common to most elastomeric materials?
 
  What will be an ideal response?

Question 2

Two crosslinkable polyesters are being considered for use as the resin in making a fiberglass-reinforced tank for processing various chemicals. One polyester is made from a glycol having four carbons between the alcohol groups and the other is made using the same acid but from a glycol having eight carbons between the alcohols. Compare the physical, chemical, and mechanical properties of the two resins. If the chemicals being processed are water-based, which resin is the best candidate on the basis of chemical resistance?
 
  What will be an ideal response?



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

leahm14

  • Sr. Member
  • ****
  • Posts: 322
Answer to Question 1

Elastomers are generally linear, aliphatic materials with structures that do not pack together easily and are therefore noncrystalline. These materials have highly random structures in their relaxed state but will become more ordered if stretched.

Answer to Question 2

The material containing the four carbons will have a higher crosslinked density and as such will have a higher shrinkage and stiffness and resistance to chemicals than the material containing the eight carbon bonds. For the same reasons as mentioned, the four carbon bonded polyester will have a better resistance to the water-based chemicals.




leahm14

  • Sr. Member
  • ****
  • Posts: 322

 

Did you know?

The term bacteria was devised in the 19th century by German biologist Ferdinand Cohn. He based it on the Greek word "bakterion" meaning a small rod or staff. Cohn is considered to be the father of modern bacteriology.

Did you know?

Computer programs are available that crosscheck a new drug's possible trade name with all other trade names currently available. These programs detect dangerous similarities between names and alert the manufacturer of the drug.

Did you know?

Only one in 10 cancer deaths is caused by the primary tumor. The vast majority of cancer mortality is caused by cells breaking away from the main tumor and metastasizing to other parts of the body, such as the brain, bones, or liver.

Did you know?

In women, pharmacodynamic differences include increased sensitivity to (and increased effectiveness of) beta-blockers, opioids, selective serotonin reuptake inhibitors, and typical antipsychotics.

Did you know?

Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.

For a complete list of videos, visit our video library