Two Polymer Science and Engineering papers (WPE 101) from BUTEX affiliated colleges' 2023 Level-1 Term-I finals. Questions cover step polymerization, free radical mechanisms, degradation types, molecular weight averages with PDI numericals, and Teflon crystallinity.
Q1
Level-1 Term-I, Final Exám-2023
Subject: Polymer Science and Engineering (Code: WPE 101)
Time: 3.0 Hrs. Full Marks: 72
(Use separate answer script for Part: A and Part: B)
(All parts of a question must be answered consecutively)
Part: A
(Answer any three questions)
1. (a) Point out the features of step polymerization process.
(b) Describe the mechanism of free radical polymerization process with reaction.
(c) What is step polymerization? Explain in brief about various types of step polymerization reactions.
[2+4+6 = 12]
2. (a) What do you mean by polymer degradation?
(b) Briefly discuss about chain end degradation and random degradation.
(c) Describe about physical and chemical factors of polymer degradation.
[2+5+5 = 12]
3. (a) Express Number-average molecular weight & Weight average molecular weight.
(b) Write short note on i) Tacticity ii) Vulcanization.
Q2
Level-1 Term-II, Final Exám-2023
Subject: Polymer Science & Engineering (Code: WPE 101)
Time: 3.0 Hrs. Full Marks: 72
(Use separate answer script for Part: A and Part: B)
(All parts of a question must be answered consecutively)
Part: A
(Answer any three questions)
1. (a) What is meant by polymer? How it is distinguish from oligomer?
(b) Differentiate between monomer and repeating unit.
(c) Show the monomers and repeating units of the following: i) Polyvinile alcohol ii) polystyrene
[4+2+6 = 12]
2. (a) Define degree of polymerization.
(b) If DP of cellulose is 5000 and DP of regenerated cellulose is 500, what will be the reduction of DP? What are the merits and demerits of this reduction.
(c) Differentiate among elastomers, plastics and biopolymers.
[4+4+4 = 12]