8/13/2019 MLE1101 - Tutorial 5
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5.
Determinethemolefractionofpolyvinylchlorideandpolyvinylacetateinacopolymerhavingamolecularweightof11,000g/molandadegreeofpolymerizationof150.
6.
Howmuchsulphurmustbeaddedto70gofbutadienerubbertocrosslink3.0%ofthemers?(Assumeallsulphurisusedtocrosslinkthemersandthatonlyonesulphuratomis
involvedineachcrosslinkingbond.)
7.
Howisitpossibleforapolymerchainsuchasapolyethyleneonetokeepgrowingspontaneouslyduringpolymerization?
8.
Howdoestheamountofcrystallinityinathermoplasticaffect(a)itsdensity,and
(b)itstensilestrength?
Explain.
9.
Howdoesthepresenceofamethylgrouponeveryothercarbonatomofthemainpolymerchainaffecttheglasstransitiontemperatureofthismaterialwhencomparedto
polyethylene?
