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Bis(4-isocyanatophenyl)methane and ethane-1,2-diol (structures shown below) can be reacted together to form polyurethane. OCN. NCO OH HO bis(4-isocyanatophenyl)methane ethane-1,2-diol (a) Draw the reaction mechanism (including curly arrows etc.) for the initial step in the polymerisation of hexane-1,6-diamine and adipoyl chloride which gives a dimer of the two monomers. [4 marks] (b) What is the degree of polymerisation (DP) at 7%, 33%, 80% and 99.5% monomer conversion for this polymerisation assuming a 1:1 molar ratio of the two monomers? [4 marks] (c) What is the number average molecular weight of the polymer at 99.5% monomer conversion? [2 marks] (d) What is the polydispersity of the polymer at 99.5% monomer conversion? [1 mark] (e) If the starting molar ratio of bis(4-isocyanatophenyl)methane to ethane-1,2- diol was 1:0.95 what would be the DP of the polymer at 99.5% monomer conversion? [3 marks] (f) Compare and contrast the end-group functionality of the two polymers resulting from the polymerisations described in part c and part e above. Use diagrams in your answer. [4 marks] (g) Name one analytical technique that might be used to confirm your answer to part f (above) and very briefly explain this technique would confirm this.