Engineering, 20.03.2020 09:46 david3253
For each of the following pairs of polymers, decide whether or not it is possible to determine whether one polymer has a higher melting temperature than other. If it is possible, then from the pull-down menu select that polymer having the higher melting temperature. If it is not possible to decide, then select "not possible" from the pull-down menu.
(a) Branched polyethylene having a number-average molecular weight of 850,000 g/mol; linear polyethylene having a number-average molecular weight of 850,000 g/mol.
1- branched polyethylenenot
2- possible
3- linear polyethylene
(b) Polytetrafluoroethylene having a density of 2.14 g/cm3 and weight-average molecular weight of 600,000 g/mol; PTFE having a density of 2.20 g/cm3 and a weight-average molecular weight of 600,000 g/mol.
`1-PTFE
2-polytetrafluoroethylene
3-not possible
(c) Linear and syndiotactic poly(vinyl chloride) having a number-average molecular weight of 500,000 g/mol; linear polyethylene having a number-average molecular weight of 225,000 g/mol.
1-linear and syndiotactic poly(vinyl chloride)
2-not possible
3-linear polyethylene
(d) Linear and syndiotactic polypropylene having a weight-average molecular weight of 500,000 g/mol; linear and atactic polypropylene having a weight-average molecular weight of 750,000 g/mol.
1-linear and syndiotactic polypropylene
2-linear and atactic polypropylene
3-not possible
Answers: 3
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For each of the following pairs of polymers, decide whether or not it is possible to determine wheth...
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