Problem 6. a. You want to make a solid tissue engineering scaffold for a vascular graft using poly(glycerol-co-sebacate) (PGS). You decide that you need to obtain a PGS film with a storage modulus (G) of 1 MPa. What should the quantity of active network chain segments per volume be to ensure this value at physiologic temperature (T = 37 C)? b. You want to use PGS for a bone tissue engineering scaffold and thus require a storage modulus (G) of 100 MPa. What should the quantity of active network chain segments per volume be to ensure this value at physiologic temperature (T = 37 C)? c. Qualitatively describe hydrolysis of PGS on the storage modulus (G). d. Sketch a qualitative plot of G vs. time for a hydrolytically labile elastomer that undergoes surface erosion. Now sketch a qualitative plot of G vs. time for a hydrolytically labile elastomer that undergoes bulk erosion. e. Explain your answers in (d)