Ps b paa

Polystyrene-block-polyacrylic acid (PS-b-PAA, batch number: MKBQ5839V) was purchased from Sigma Aldrich (Steinheim, Germany). The molecular weights were determined by GPC with the solvent THF and PS as the standard. A value of 27,617 g/mol was obtained for PS and 1761 g/mol for PAA, leading to a total molecular weight of 29,378 g/mol with a polydispersity ≤1.1. The degree of polymerization of PS was 275 and of PAA 30. Deionized water was used as the selective solvent for polystyrene and for the silica synthesis. Tetrahydrofuran (THF, not stabilized, for HPLC) from Sigma Aldrich (Steinheim, Germany) served as the solvent for PS-b-PAA. Tetraethylorthosilicate (TEOS, for synthesis; purity ≥ 99.0%), aqueous ammonia solution 25% (for analysis, Reag. Ph. Eur.), 3-aminopropyl triethoxysilane (APTES; purity ≥ 98.0%), hexanoic acid (for synthesis; purity ≥ 98.0%), octanoic acid (for synthesis; purity ≥ 99.0%), decanoic acid (for synthesis; purity ≥ 98.0%), N,N’-diisopropylcarbodiimide (DIC, for synthesis; purity ≥ 99.0%) from Sigma Aldrich (Steinheim, Germany), and absolute ethanol (purity ≥ 99.8%, Reag. Ph. Eur.) from VWR chemicals (Darmstadt, Germany) were used for silica synthesis and surface functionalization.

Polystyrene-block-polyacrylic acid (PS-b-PAA, batch: MKBQ5839V) was purchased from Sigma Aldrich (Steinheim, Germany). The degree of polymerization of PS is 275 and of PAA 30, as stated by the manufacturer. The molecular weights (M_n) and the polydispersity index (PDI) of PS-b-PAA are summarized in Table 1.
Deionized water was used as the selective solvent for the hydrophobic part (polystyrene). Tetrahydrofuran (THF, for HPLC, not stabilized) and 1,4-dioxane (for HPLC, not stabilized) from Carl Roth (Karlsruhe, Germany) were utilized as good solvents for PS-b-PAA.
Filters were used for microscopy (Whatman^® Nuclepore™ track-etched polycarbonate membranes, with pore diameters of between 0.2 µm and 2.0 µm, Dassel, Germany). A quartz glass cuvette (Hellma Analytics, Type 100 QS, Müllheim, Germany) with a layer thickness of 10 mm and a nominal volume of 3.5 mL was used for dynamic light scattering measurements.