4 4 0 azobis 4 cyanopentanoic acid

Styrene (Sigma Aldrich, 99%) was deinhibited over activated basic alumina prior to each polymerization. The RAFT agents TTC 2 (ABCR, 97%) and TTC 3 (ABCR, 97%) were used as received. The chemicals used as reactants, acryloyl chloride (ABCR, 96%, stabilized with phenothiazine), pyrrolidine (Acros, 99%), butanethiol (Sigma Aldrich, 99%), potassium hydroxide (Merck, 485%), carbon disulfide (Merck, 99%), p-tosyl chloride (Merck, 98%), and 4,4 0 -azobis(4-cyanopentanoic acid) (Sigma Aldrich, 98%) were used as received. All solvents for reactions, purifications, and NMR, dichloromethane (Acros, 99.9%), 1,4-dioxane (Gru ¨ssing, 99%), dimethylformamide (VWR, 99.5%), acetone (Merck, 99%), methyl acetate (Merck, 99%), n-hexane (VWR Chemicals, 95%), chloroform-d 1 (Euriso-Top, 99.8%), and tetrahydrofuran-d 8 (Euriso-Top, 99.5%) were used without further purification. All other chemicals, sodium chloride Gru ¨ssing (99%), KHSO 4 (Gru ¨ssing, 99%), NaHCO 3 (Gru ¨ssing, 99%), Mg 2 SO 4 (Gru ¨ssing, 99%), and activated basic aluminum oxide (Merck, 99%, grain size between 0.063-0.200 mm) were also used as received.

Glycerol monomethacrylate (GMA) was donated by GEO Specialty Chemicals (Hythe, UK). Methyl methacrylate (MMA; 99%), benzyl methacrylate (BzMA; 96%), 4,4 0 -azobis(4-cyanopentanoic acid) (ACVA; 98%), 2,2 0 -azobisisobutyramide dihydrochloride (AIBA; 99%) and 2-cyano-2-propyl benzodithioate (CPDB; 97%) were purchased from Sigma-Aldrich (UK) and used as received. 4-Cyano-4-(2-phenylethanesulfanylthiocarbonyl)-sulfanylpentanoic acid (PETTC) was prepared according to a literature protocol. 88 Morpholine-functionalized, trithiocarbonate-based RAFT agent (MPETTC) was prepared according to a literature protocol. 89 Synthesis of neutral (0) PGMA 50 into a ten-fold excess of dichloromethane (three times). A mean degree of polymerization (DP) of 50 was determined by endgroup analysis via 1 H NMR spectroscopy (integrated aromatic proton signals at 7.4-7.8 ppm were compared to the methacrylic backbone protons at 0.7-2.5 ppm). A similar protocol was employed for the synthesis of the anionic (À) PGMA 54 precursor and the cationic (+) PGMA 48 precursor by RAFT solution polymerization in ethanol (see ESI † for further details).