Example 6
The macromonomer (b-1) (5 g) synthesized above was added to a 200 mL three-neck flask and dissolved in THF (50 mL). 4,4′-Diphenylmethane diisocyanate (10.2 g) was added to this solution and dissolved at 60° C. NEOSTAN U-600 (trade name, manufactured by Nitto Kasei Co., Ltd.) (0.05 g) was added to this solution and, furthermore, continuously heated and stirred at 60° C. for two hours. This solution was cooled to 5° C., then, terminal diamine polyethylene propylene glycol (JEFFAMINE ED600 (trade name), number-average molecular weight: 600, manufactured by Huntsman Corporation) (9.1 g) was added thereto, and the components were further continuously stirred at 5° C. for one hour. The obtained polymer solution was added to hexane and precipitated, and the residue was dried in a vacuum at 80° C. for 12 hours. The weight-average molecular weight was 37,600.