Supporting Information. LCST-Type Phase Separation of Poly[poly(ethylene glycol) methyl ether methacrylate]s in Hydrofluorocarbon

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1 Supporting Information LCST-Type Phase Separation of Poly[poly(ethylene glycol) methyl ether methacrylate]s in Hydrofluorocarbon Yuta Koda, Takaya Terashima*, and Mitsuo Sawamoto* Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University Katsura, Nishikyo-ku, Kyoto , Japan Tel: , Fax: *: corresponding authors Contents Experimental Section S2 Supporting Data Table S1. Characterization of Poly(PEGMA)s S5 Figure S1. SEC curves of poly(pegma) S5 Figure S2. LCST-type phase separation of poly(pegma)s S6 References S6 S1

2 Experimental Section Materials Ethyl-2-chloro-2-phenylacetate (ECPA; Aldrich; purity > 98%) was purified by distillation under reduced pressure before use. Poly(ethylene glycol) methyl ether methacrylate [PEGMA: CH 2 =C(CH 3 )CO 2 (CH 2 CH 2 O) m CH 3 ; Aldrich; M n = 300 (m = 4.5) and 500 (m = 9)] was purified by column chromatography charged with inhibitor remover (Aldrich) and purged by argon before use. PEGMA [Aldrich; M n = 950 (m = 19)] was purged by argon before use. Methyl methacrylate (MMA; TCI; purity >99%) was dried overnight over calcium chloride and purified by distillation on CaH 2 under reduced pressure before use. [RuCp*(µ 3 -Cl)] 4 (Cp*: pentamethylcyclopentadienyl), prepared according to the literature, 1 1,2-bis(diphenylphosphino)-ethane monooxide (PO-2; Aldrich, purity > 97%), and P(m-tol) 3 [m-tol: tri(m-tolyl)phosphine, Strem, purity > 98%] were handled in a globe box under a moisture- and oxygen-free argon atmosphere (H 2 O < 1 ppm, O 2 < 1 ppm). n-bu 2 NH (TCI; purity > 98%) and 4-dimethylamino-1-butanol (4-DMAB; TCI; purity > 98%) were purged by argon before use. Tetralin (1,2,3,4-tetrahydronaphthalene; TCI; purity > 98%), an internal standard to determine monomer conversion by 1 H NMR, was dried over calcium chloride overnight and distilled from calcium hydride. Toluene (Kishida Chemical; purity > 99%) was purified before use; passing it through a purification column (Glass Contour Solvent Systems by SG Water, USA). 2H,3H-perfluoropentane [CF 3 (CHF) 2 CF 2 CF 3 : 2HPFP; TCI; purity > 98% including isomers] was used as received. Characterization Number-average molecular weight (M n ) and molecular weight distribution (M w /M n ) of the polymers were measured by size exclusion chromatography (SEC) in DMF containing 10 mm LiBr at 40 o C (flow rate: 1 ml/min) on three linear-type polystyrene gel columns (Shodex KF-805L: exclusion limit = g/mol; particle size = 10 µm; pore size = 5000 Å; 0.8 cm i.d. 30 cm) that were connected to a Jasco PU-2080 precision pump, a Jasco RI-2031 refractive index detector, and a Jasco UV-2075 UV/vis detector set at 270 nm. The columns were calibrated against 10 standard poly(methyl methacrylate) samples (Polymer Laboratories: M n = ; M w /M n = ). 1 H NMR spectra were recorded in acetone-d 6, CDCl 3, and 2HPFP with CDCl 3 at 27, 30, 47, and 50 o C on a JEOL JNM-ECA500 spectrometer, operating at MHz. When 1 H NMR measurement of polymers was conducted in 2HPFP, the capillary containing the 2HPFP solution of polymers was placed inside a NMR tube with CDCl 3 (0.5 ml). Ultraviolet-visible (UV/Vis) spectra were recorded in H 2 O or 2HPFP on UV-1800 (Shimadzu, optical path length = 1.0 cm). S2

3 Polymer Synthesis The synthesis of PEGMA polymers (P1 P3) and a MMA/PEGMA block copolymer was carried out by syringe technique under argon in a baked glass tube or round-bottom flask equipped with a three-way stopcock. P1: A ruthenium complex stock solution was first prepared by mixing [RuCp*(µ 3 -Cl)] 4 (0.026 mmol, 28 mg) and PO-2 (0.21 mmol, 85 mg) in toluene (3.4 ml) in a baked glass tube at 60 o C for 12 h. Toluene (8.8 ml), tetralin (0.1 ml), a 400 mm toluene solution of n-bu 2 NH (0.18 mmol, 0.45 ml), PEG4.5MA (9.1 mmol, 2.6 ml), and a 670 mm toluene solution of ECPA (0.036 mmol, ml) were sequentially added into a glass tube at 25 o C under argon. Into the mixture, the Ru stock solution (0.6 ml) was then added at 25 o C (total volume: 12.6 ml). The glass tube with the mixture was placed in an oil bath kept at 80 o C. After 56 h, the reaction was terminated by cooling the mixture to 78 o C. The conversion of PEG4.5MA was determined as 82% by 1 H NMR with tetralin as an internal standard. The crude product was purified by silica gel column chromatography with toluene as an eluent and was further dialyzed against methanol and water with a regenerated cellulose membrane [Spectra/Por 7; molecular weight cut-off (MWCO) 15000]. The inner aqueous solution was liophilized to give a colorless product (P1). SEC: M n = g/mol; M w /M n = H NMR [500 MHz, acetone-d 6, 30 o C, δ = 2.05 (acetone)]: δ (aromatic), 6.2, 5.7 (olefin), ( CO 2 CH 2 ), ( CO 2 CH 2 CH 2 O ), ( OCH 2 CH 2 O ), ( OCH 2 CH 2 OCH 3 ), ( OCH 3 ), ( CH 2 ), ( CCH 3 ). P2 was similarly synthesized with PEG9MA. P3: A ruthenium complex stock solution was first prepared by mixing [RuCp*(µ 3 -Cl)] 4 (0.011 mmol, 12 mg) and P(m-tol) 3 (0.092 mmol, 28 mg) in toluene (2.2 ml) in a baked glass tube at 60 o C for 12 h. PEG19MA (6.4 mmol, 6.09 g, 5.54 ml) was placed in a 100 ml round-bottom flask and purged by argon. Into the flask, ethanol (11.4 ml), tetralin (0.2 ml), a 500 mm ethanol solution of 4-DMAB (0.26 mmol, 0.51 ml), and a 570 mm toluene solution of ECPA (0.032 mmol, ml) were sequentially added at 25 o C under argon. Into the mixture, the Ru stock solution (0.64 ml) was then added at 25 o C (Total volume: 18.3 ml). The flask with the mixture was placed in an oil bath kept at 40 o C. After 26 h, the reaction was terminated by cooling the mixture to 78 o C. The conversion of PEG19MA was determined as 80% by 1 H NMR with tetralin as an internal standard. The crude product was purified by silica gel column chromatography with toluene as an eluent and was dialyzed against methanol and water with a regenerated cellulose membrane [Spectra/Por 7; molecular weight cut-off (MWCO) 15000]. The inner aqueous solution was liophilized to give a white solid product (P3). SEC: M n = g/mol; M w /M n = H NMR [500 MHz, acetone-d 6, 30 o C, δ = 2.05 (acetone)]: δ (aromatic), 6.1, 5.8 (olefin), ( CO 2 CH 2 ), ( CO 2 CH 2 CH 2 O ), ( OCH 2 CH 2 O ), S3

4 ( OCH 2 CH 2 OCH 3 ), ( OCH 3 ), ( CH 2 ), ( CCH 3 ). MMA/PEG19MA Block Copolymer: A ruthenium complex stock solution was first prepared by mixing [RuCp*(µ 3 -Cl)] 4 (0.016 mmol, 17 mg) and P(m-tol) 3 (0.14 mmol, 42 mg) in toluene (3.2 ml) in a baked glass tube at 60 o C for 12 h. PEG19MA (7.9 mmol, 7.52 g, 6.84 ml) and PMMA Cl macroinitiator [0.147 mmol, 1.63 g, M n = g/mol, M w /M n = 1.15, M n (NMR) = g/mol] were placed in a 200 ml round-bottom flask and purged by argon. Into the flask, DMF (7.2 ml) was first added to solubilize PEG19MA and PMMA Cl, and subsequently tetralin (0.1 ml), a 500 mm ethanol solution of 4-DMAB (0.50 mmol, 1.0 ml), ethanol (7.2 ml), and the Ru stock solution (1.3 ml) were added at 25 o C (Total volume: 25.3 ml). The flask with the mixture was placed in an oil bath kept at 40 o C. After 23 h, the reaction was terminated by cooling the mixture to 78 o C. The conversion of PEG19MA was determined as 98% by 1 H NMR. The crude product was purified by silica gel column chromatography with toluene as an eluent and was dialyzed against methanol and CH 2 Cl 2 with a regenerated cellulose membrane [Spectra/Por 7; MWCO 3500]. The inner CH 2 Cl 2 solution was evaporated to give a solid product. SEC: M n = g/mol; M w /M n = H NMR [500 MHz, CD 2 Cl 2, 30 o C, δ = 5.32 (CHDCl 2 )]: δ (aromatic), ( CO 2 CH 2 ), ( OCH 3, OCH 2 CH 2 O ), ( OCH 2 CH 2 OCH 3 ), ( CH 2 ), ( CCH 3 ); M n (NMR) = g/mol (DP: MMA/PEG19MA = 110/55). 1 H T 1 and T 2 Measurements 1 H spin-lattice relaxation time (T 1 ) and spin-spin relaxation time (T 2 ) measurements of P2 were conducted in CDCl 3 or in 2HPFP with CDCl 3 at 30 o C ([polymer] = 30 mg/ml). For the measurement in 2HPFP, the capillary containing a 2HPFP solution of polymers ([polymer] = 30 mg/ml) was placed inside a NMR tube with CDCl 3 (0.5 ml). 1 H T 1 values were determined with a standard inversion-recovery pulse sequence. The delay (τ) between the inversion pulse and the read pulse was varied along 16 values with a minimum value of 25 ms and the maximum value of 20 s (in 2HPFP) or 30 s (in CD 2 Cl 2 ). The NMR samples were not spinning for the measurement. The number of scans was set at 32. Other parameters were as follows: spectral width = 15 ppm; 90 pulse width = 13.5 µs; relaxation delay = 20 s (in 2HPFP) or 30 s (in CD 2 Cl 2 ); data points = H T 2 values were determined using the Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence using 16 values of τ, with a minimum value of 25 ms and the maximum value of 20 s (in 2HPFP) or 30 s (in CD 2 Cl 2 ). The NMR samples were not spinning for the measurement. The number of scans was set at 32. Other parameters were as follows: spectral width = 15 ppm; 90 pulse width = 13.5 µs; relaxation delay = 20 s (in 2HPFP) or 30 s (in CD 2 Cl 2 ); data points = S4

5 Supporting Data Table S1. Poly(PEGMA)s Obtained from Ruthenium-Catalyzed Living Radical Polymerization a Code Monomer Time (h) Conversion (%) b M n c (SEC) M w /M n c (SEC) DP b (NMR) M n b (NMR) mm/mr/rr (%) d P1 PEG4.5MA /34/62 P2 PEG9MA /32/65 P3 PEG19MA /24/73 a P1: [PEG4.5MA] 0 /[ECPA] 0 /[RuCp*Cl(PO-2) 2 ] 0 /[n-bu 2 NH] 0 = 722/2.9/1.5/14 mm in toluene at 80 o C. P2: [PEG9MA] 0 /[ECPA] 0 /[RuCp*Cl(PO-2) 2 ] 0 /[n-bu 2 NH] 0 = 750/3.0/1.5/15 mm in toluene at 80 o C. P3: [PEG19MA] 0 /[ECPA] 0 /[RuCp*Cl(P(m-tol) 3 ) 2 ] 0 /[4-DMAB] 0 = 330/1.6/0.66/13 mm in ethanol at 40 o C. b Determined by 1 H NMR. c Determined by SEC in DMF (10 mm LiBr) with PMMA standard calibration. d Stereoregularity determined by 1 H NMR. Figure S1. SEC curves of P1 P3 obtained from ruthenium-catalyzed living radical polymerization of PEGMA [m = 4.5 (P1), 9 (P2), 19 (P3)]. P1: [PEG4.5MA] 0 /[ECPA] 0 /[RuCp*Cl(PO-2) 2 ] 0 /[n-bu 2 NH] 0 = 722/2.9/1.5/14 mm in toluene at 80 o C. P2: [PEG9MA] 0 /[ECPA] 0 /[RuCp*Cl(PO-2) 2 ] 0 /[n-bu 2 NH] 0 = 750/3.0/1.5/15 mm in toluene at 80 o C. P3: [PEG19MA] 0 /[ECPA] 0 /[RuCp*Cl{P(m-Tol) 3 } 2 ] 0 /[4-DMAB] 0 = 330/1.6/0.66/13 mm in ethanol at 40 o C. S5

6 Polymer / m Poly(MMA) / 0 Cp in H 2 O Insoluble Cp in CF 3 (CHF) 2 CF 2 CF 3 Non P1 / 4.5 P2 / 9 63 o C 90 o C Solubility 52 o C 46 o C Solubility P3 / 19 Non 41 o C Figure S2. LCST-type phase separation of poly(pegma)s (P1 P3) in H 2 O or 2HPFP. References (1) Yoda, H; Nakatani, K.; Terashima, T.; Ouchi, M.; Sawamoto, M. Macromolecules 2010, 43, S6