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 99 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?

For high blood pressure (hypertension), a new class of drug, called a vasopeptidase blocker (inhibitor), has been developed. It decreases blood pressure by simultaneously dilating the peripheral arteries and increasing the body's loss of salt.

Did you know?

Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.

Did you know?

Once thought to have neurofibromatosis, Joseph Merrick (also known as "the elephant man") is now, in retrospect, thought by clinical experts to have had Proteus syndrome. This endocrine disease causes continued and abnormal growth of the bones, muscles, skin, and so on and can become completely debilitating with severe deformities occurring anywhere on the body.

Did you know?

The term pharmacology is derived from the Greek words pharmakon("claim, medicine, poison, or remedy") and logos ("study").

Did you know?

Chronic necrotizing aspergillosis has a slowly progressive process that, unlike invasive aspergillosis, does not spread to other organ systems or the blood vessels. It most often affects middle-aged and elderly individuals, spreading to surrounding tissue in the lungs. The disease often does not respond to conventionally successful treatments, and requires individualized therapies in order to keep it from becoming life-threatening.

For a complete list of videos, visit our video library