Producing polymers with high molecular weights is difficult in
step polymerizations. Why is it difficult and which techniques
exist to overcome this difficulty?
31. What is the initiator in the polymerization of isobutylene?
32. What is the general name of the product produced by cationic
initiation?
33. What reactant besides the monomer is present in cationic
chain propagation reactions?
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31. What is the initiator in the polymerization of isobutylene?
32. What is the general name of the product produced by cationic
initiation?
33. What reactant besides the monomer is present in cationic
chain propagation reactions?
Answer about anionic ‘living’ polymerization:
(a) What number-average molecular weight (Mn) polystyrene would be
formed by polymerization of 10 g styrene with 0.1 g of butyl
lithium, under complete living polymer system?
(b) Suggest three different ways to synthesize
polystyrene-b-polybutadiene-b-polystyrene (SBS) tri-block copolymer
with controlled block length.
1. What are some advantages and disadvantages of the general
contract approach? Assume that the general contact will be awarded
on the basis of competitive lump sum bidding.
2. What are the possible options and how a contracting method is
selected for a federal-aided highway project?
For the molecular compound carbon tetrabromide, what would you
multiply "molecules of CBr4" by to get the units "grams of
CBr4"?
For the molecular compound carbon dioxide, what would you
multiply "molecules of CO2" by to get the units "grams of CO2"?
How many ATOMS of carbon are present in 1.85 moles of carbon
monoxide ? How many MOLES of oxygen are present in 3.38×1022
molecules of carbon monoxide ?
How many GRAMS of sulfur are present in 2.60 grams...
How specifically do you get a readers attention in the
introduction ? What style or approach did you use, and what do you
hope to achieve by using it ? Why is this strategy strong ?