Interested to Buy Any Domain ? << Click Here >> for more details...
POLYMER ENGINEERING - QUESTION 24.1 : The molecular weights M in kg / mol of 3 different monomers a, b and c in a polymer are Ma = 14, Mb = 16 and Mc = 18. The fraction of polymer chain X of 3 different monomers a, b and c in a polymer are Xa = 0.5, Xb = 0.3 and Xc = 0.2. (i) Calculate number average molecular weight by using the formula Ma Xa + Mb Xb + Mc Xc. (ii) Calculate weight average molecular weight by using the formula (Ma Xa Ma + Mb Xb Mb + Mc Xc Mc) / (Ma Xa + Mb Xb + Mc Xc). (iii) Calculate the polydispersity by using the answer in (ii) divided by answer in (i). (iv) If the molecular weight of repeat unit is 12, calculate the degree of polymerization by using the formula (Ma Xa + Mb Xb + Mc Xc) / (molecular weight of repeat unit).
- 1 Answers
- 2643 Views
- I also Faced
- E-Mail Answers
Answer Posted / kangchuentat
POLYMER ENGINEERING - ANSWER 24.1 : (i) Number average molecular weight = Ma Xa + Mb Xb + Mc Xc = 14 x 0.5 + 16 x 0.3 + 18 x 0.2 = 15.4 kg / mol. (ii) Weight average molecular weight = (Ma Xa Ma + Mb Xb Mb + Mc Xc Mc) / (Ma Xa + Mb Xb + Mc Xc) = (14 x 0.5 x 14 + 16 x 0.3 x 16 + 18 x 0.2 x 18) / 15.4 = 15.558 kg / mol. (iii) Polydispersity = [ answer in (ii) ] / [ answer in (i) ] = 15.558 / 15.4 = 1.0103. (iv) Degree of polymerization = (Ma Xa + Mb Xb + Mc Xc) / (molecular weight of repeat unit) = (15.4 kg / mol) / (12 g / mol) = 1.283 k = 1283. The answer is given by Kang Chuen Tat; PO Box 6263, Dandenong, Victoria VIC 3175, Australia; SMS +61405421706; chuentat@hotmail.com; http://kangchuentat.wordpress.com.
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
Why is post-weld heat treatment (stress relieving) sometimes necessary for welded vessels?
List the advantages and disadvantages of a pfr?
Can asphalt be recycled to form a useful product?
How to caliculate the boil up rate, dia and height in both packed and tray distillation columns and any referance books for the design.
Explain the use of gear pumps in motor?
What diffrence between flush distillation & batch distillation ?
A shiny brown colored element ‘x’ on heating in air becomes black in cooler name the element ‘x’and black colored compound formed?
Explain some of the consequences of an undersized kettle type reboiler?
Explain how can one estimate how the friction factor changes in heat exchanger tubes with a change in temperature?
What are the advantages of using gear pumps?
why traction voltage is 25kv
What are the merits of using a falling film evaporator?
What is the wet bulb globe temperature (wbgt)?
What are the criteria’s involved in choosing mass balances for components?
Explain what type of flow measurement devices is best for slurries?
