 Phase separation can be modified to fit many different applications, and pore structure can be varied by using different solvents, which can change the entire process from liquid–liquid to solid–liquid.Porosity and fiber diameter can also be modified by varying the initial concentration of the polymer; a higher initial concentration leads to less pores and larger fiber diameters.This technique can be used to create networks of fibers with diameters reaching type I collagen fiber diameters.