Arium pro vf system

N-Isopropylacrylamide (NIPAM, TCI Germany GmbH, Eschborn, Germany; 97%) was recrystallized from n-hexane. N,N′-methylenebisacrylamide (BIS, Sigma-Aldrich, Munich, Germany; 99%), sodium dodecyl sulfate (SDS, Sigma-Aldrich, Munich, Germany; $>$  99.5%), ammonium peroxodisulfate (APS, Sigma-Aldrich, Munich, Germany; ≥ 98%), 2-hydroxy-4-(methacryloyloxy)-benzophenone (HMABP, Alfa Aesar, Karlsruhe, Germany; 99%), PdCl₂ (Sigma-Aldrich, Munich, Germany; $>$  99.9%), ammonia (Carl Roth, Karlsruhe, Germany; 25%), HCl (0.1 M, Fischer Scientific GmbH, Schwerte, Germany, volumetric solution), NaOH (0.1 M, Fischer Scientific GmbH, Schwerte, Germany, volumetric solution), NH₄Cl (Carl Roth, Karlsruhe, Germany; ≥ 99.5%), acetic acid (VWR International, Eschborn, Germany; 100%), sodium acetate trihydrate (Sigma-Aldrich, Munich, Germany; ≥ 97%) and sodium borohydride (Sigma-Aldrich, Munich, Germany; 98.0%) were used without further purification. Water was purified using an Arium pro VF system (Sartorius AG, Göttingen, Germany).

N-isopropylacrylamide (NIPAM; Sigma-Aldrich Chemie GmbH Munich, Germany; purity 97%) and N-isopropylmethacrylamide (NIPMAM; Sigma-Aldrich, Chemie GmbH, Munich, Germany; purity 97%) were purified by recrystallisation from hexane. The cross-linker N,N’-methylenebisacrylamide (BIS; Sigma-Aldrich Chemie GmbH, Munich, Germany; purity 99%), the initiator ammonium persulfate (APS; Sigma-Aldrich Chemie GmbH, Munich, Germany; purity ≥ 98%) and pyrene (Sigma-Aldrich Chemie GmbH, Munich, Germany; purity ≥ 99%) were used without further purification. For all experiments, purified water from an Arium®pro VF system (Sartorius AG, Göttingen, Germany) was used.
N-n-propylacrylamide (NNPAM) was synthesized via a Schotten–Baumann reaction published by Hirano et al. [21 ]. For this reaction, acryloylchloride (Sigma-Aldrich Chemie GmbH, Munich, Germany; purity 98%), n-propylamine (Fluka, Sigma-Aldrich Chemie GmbH, Munich, Germany; purity 99%), triethylamine (Grüssing GmbH Analytika, Filsum, Germany; purity 99%) and methylenchloride (p.a.) were used as received. The obtained monomer NNPAM was washed with NaHCO ${}_3$ (10 wt %) and dried over MgSO ${}_4$ . After filtration, the solvent was evaporated and the product was distilled in vacuum (115 ${}^{°}$ C, 10 mbar).

If not stated otherwise, all chemicals were used without further purification. For microgel syntheses N-isopropylacrylamide (NIPAM, 97%; TCI Germany GmbH, Eschborn, Germany) recrystallized from n-hexane (p.a.; VWR International GmbH, Darmstadt, Germany), N-(3-aminopropyl)methacrylamide hydrochloride (APMH, 97%; Sigma Aldrich, Munich, Germany), N,N ${}^{\prime }$ -methylenebisacrylamide (BIS, 99%; Sigma Aldrich) and 2,2 ${}^{\prime }$ -azobis(2-methylpropionamidine) dihydrochloride (V50, 97% granular; Sigma Aldrich) were used. Deuteriumoxide (99.9%) and deuteriumchloride solution (36–38% in D₂O) were purchased from Deutero GmbH, Kastellaun, Germany. Sodium hydroxide solution and hydrochloric acid ( $0.1$ M, Fisher Chemical, Waltham, MA, USA) were used for pH-adjustments, sodium chloride (>99.9%; Carl Roth, Karlsruhe, Germany) was used to alter ionic strength. Water was purified using an Arium pro VF system (Sartorius AG, Göttingen, Germany).

Ultrapure water was produced using an Arium pro VF system (Sartorius AG, Germany). Nitric acid (65% w/w, EMSURE^® ISO, for analysis), hydrofluoric acid (40%, Suprapur^® for trace analysis) and hydrochloric acid used for microwave digestion (30% Suprapur^®) were purchased from VWR, Germany. HNO₃ was sub-boiled (dst-1000, Savillex, USA). For inductively coupled plasma (ICP)-based measurements, HCl Trace SELECT^® Ultra (Sigma Aldrich, Germany) was used.

N-n-propylacrylamide (NNPAM) was synthesized via a Schotten–Baumann reaction published by Hirano et al. [54 (link)]. For this reaction, acryloylchloride (Sigma-Aldrich Chemie GmbH, Munich, Germany; purity 98%), n-propylamine (Fluka, Sigma-Aldrich Chemie GmbH, Munich, Germany; purity 99%), triethylamine (Grüssing GmbH Analytika, Filsum, Germany; purity 99%), and methylenechloride (p.a.) were used as received. The obtained monomer NNPAM was washed with $\mathrm{N}\mathrm{a}\mathrm{H}\mathrm{C}{\mathrm{O}}_3$ (10 wt%) and dried over $\mathrm{M}\mathrm{g}\mathrm{S}{\mathrm{O}}_4$ . After filtration, the solvent was evaporated and the product was distilled in vacuum (115 °C, 10 mbar). N-isopropylacrylamide (NIPAM; Sigma-Aldrich Chemie GmbH, Munich, Germany; purity 97%) and N-isopropylmethacrylamide (NIPMAM; Sigma-Aldrich Chemie GmbH, Munich, Germany; purity 97%) were purified by recrystallization from hexane. The cross-linker N,N’-methylenebisacrylamide (BIS; Sigma-Aldrich Chemie GmbH, Munich, Germany; purity 99%) and the initiator ammonium persulfate (APS; Sigma-Aldrich Chemie GmbH, Munich, Germany; purity ≥98%) were used without further purification. For all experiments, purified water from an Arium pro VF system (Sartorius AG, Göttingen, Germany) was used.