To expand the availability and solubility range of polymer supports for liquid-phase organic synthesis (LPOS) we have applied a sequence of normal and “living” free radical polymerization to generate a library of block copolymers possessing either block or graft architecture with initiators 1−4 and a diverse set of vinyl monomers 5−9. The structure, molecular weight, and polydispersity (PD) of the individual library members have been determined by size exclusion chromatography (SEC), 1H and 13C NMR, and as a function of the solubility of each polymer in a range of solvents. One copolymer, polyBS-DS (Mn = 17 000, PD = 1.54) derived from 4-tert-butylstyrene (6, BS), 3,4-dimethoxystyrene (7, DS), and initiator 1 has a solubility profile [soluble in toluene, tetrahydrofuran (THF), ether, acetone and methylene chloride (DCM), insoluble in methanol and water] that is different from the present polymer of choice for LPOS, poly(ethylene) glycol (PEG), and has been studied in some detail as a new support in LPOS. ...