Macromolecules
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amine (Aldrich, 97%) and 2-adamantylamine hydrochloride (Aldrich,
99%) were used without further purification. Triethylamine was distilled
over CaH2. tert-Butyl methacrylate (tBMA) was distilled over CaH2 in
vacuo and subsequently distilled from trioctylaluminum (2 mol %) on a
vacuum line.24 THF utilized in the polymerization procedure was
refluxed over sodium wire for 5 h and then distilled from lithium
aluminum hydride and eventually distilled from its sodium naph-
thalenide (Na-Naph) solution on the vacuum line. Lithium
naphthalenide (Li-Naph) and potassium naphthalenide (K-Naph)
were prepared by the reactions of a small excess amount of naphthalene
with the corresponding alkali metal in dry THF at room temperature.
Diphenylmethylpotassium (Ph2CHK) and diphenylmethyllithium
(Ph2CHLi) were synthesized by the reactions of 1.5 molar excess of
diphenylmethane with the corresponding alkali metal naphthalenide (K-
Naph and Li-Naph) in dry THF at room temperature for 3 days.
Oligo(α-methylstyryl)dipotassium was prepared prior to the polymer-
izations from K-Naph and 2−4-fold α-methylstyrene (α-MeSt) in THF
at −78 °C for 10 min. The initiators and tBMA were stored at −30 °C in
ampules equipped with break-seals.
C(6)H2, C(9)H2), 2.40−2.43 (m, 2H, C(2)H), 3.45 (s, 1H, C(1)H),
5.28−5.83 (2d, 2H, CH2, J = 10.9 and 17.6 Hz), 6.69−6.79 (dd, 1H,
−CH, J = 10.9 and 17.6 Hz), 7.42−7.75 (m, 4H, aromatic), 8.32 (s,
1H, CHN). 13C NMR (75 MHz, CDCl3): δ = 27.8−28.7 (C7, C8),
32.4 (C4, C6), 35.9 (C2), 37.8 (C3, C5), 38.5 (C9), 74.9(C1), 115.1
(Cβ), 126.7 (Cb), 128.7 (Cc), 136.9 (Cd), 137.0 (Cα), 139.7 (Ca),
157.7 (Ca′). IR (KBr, cm−1): 2932, 2893, 2849, 1640 (CHN), 1604,
1560, 1448, 1387, 1352, 1300, 1105, 1056, 1018, 966, 909, 849, 838.
Anal. Calcd for C19H23N (265.39): C, 85.99; H, 8.74; N, 5.28. Found: C,
86.17; H, 9.15; N, 5.12.
Anionic Polymerization of 1 and 2. All polymerizations were
carried out under high-vacuum conditions in the sealed all-glass reactors
equipped with break-seals.8 The reactors were prewashed with initiator
solutions after sealing off from the vacuum line. The polymerizations
were usually performed by pouring a THF solution of monomer to the
initiator solutions in THF at −78 °C (dry ice−acetone bath) for 1 h. The
polymerizations were terminated with degassed methanol, and the
reaction solutions were poured into methanol to precipitate polymers.
The polymers were further purified by reprecipitation in THF/MeOH.
The resulting polymers were then dissolved in benzene and freeze-dried
under vacuum condition for characterization. The resulting poly(1) and
1
Measurements. H and 13C NMR spectra were measured on a
Bruker DPX300 in CDCl3. Chemical shifts were recorded in ppm
1
poly(2) were characterized by H and 13C NMR, IR, and elemental
downfield relative to CHCl3 (δ 7.26) and CDCl3 (δ 77.1) for 1H and 13
C
analysis. 1H and 13C NMR spectra of poly(1) are shown in Figure 3b and
NMR as standard, respectively. IR spectra (KBr disk) were recorded on
a JASCO FT/IR-4100 instrument. Size exclusion chromatogram (SEC)
curves for determination of Mw/Mn were obtained in THF at 40 °C at
flow rate of 1.0 mL min−1 with a Viscotek TDA302 equipped with three
polystyrene gel columns (TSKgelG5000HHR + G4000HHR
+
G3000HHR). The combination of viscometer, right angle laser light
scattering detection (RALLS), and refractive index (RI) detection was
applied for the online SEC system in order to determine the absolute
molecular weights of polymer. A Seiko Instrument TG/DTA6200 was
used for TGA analysis at 30−600 °C under nitrogen flow with heating
rate of 20 °C min−1. The Tg of the polymer was measured by DSC using
a Seiko instrument DSC6220 apparatus under nitrogen flow. The
polymer sample was first heated to 100 °C, cooled to 30 °C, and then
scanned at a rate of 20 °C min−1 under nitrogen.
N-(1-Adamantyl)-N-4-vinylbenzylideneamine (1). A benzene
(50 mL) solution of 4-formylstyrene (8.74 g, 66.2 mmol), 1-
adamantylamine (11.0 g, 72.8 mmol), and catalytic amount of p-
toluenesulfonic acid was refluxed for 24 h with azeotropic separation of
water by means of a Dean−Stark water trap (Scheme 1). The reaction
was quenched with NaHCO3 solution, and the layer was separated. The
aqueous layer was extracted three times with diethyl ether. The organic
phase was combined and dried over anhydrous MgSO4. After
evaporation of the solvent, the residue was purified by the
recrystallization from hexane to afford a white solid (12.30 g, 46.4
mmol, 70%, mp = 82−83 °C). 1H and 13C NMR spectra of 1 are shown
Figure 3. 1H NMR spectra of 1 and poly(1) obtained with Ph2CHK in
THF.
1
in Figure S1. H NMR (300 MHz, CDCl3): δ = 1.67−1.78 (m, 6H,
C(2)H2), 1.82 (s, 6H, C(4)H2), 2.17 (s, 3H, C(3)H), 5.27−5.83 (2d,
2H, CH2 , J = 10.9 and 17.6 Hz), 6.69−6.78 (dd, 1H, −CH, J = 10.9
and 17.6 Hz), 7.42−7.72 (m, 4H, aromatic), 8.26 (s, 1H, CHN). 13C
NMR (75 MHz, CDCl3): δ = 29.7 (C3), 36.7 (C4), 43.2 (C2), 57.7
(C1), 114.8 (Cβ), 126.4 (Cb), 128.2 (Cc), 136.5 (Cd), 136.8 (Cα),
139.4 (Ca), 154.7 (Ca′). IR (KBr, cm−1): 3002, 2902, 2848, 1642
(CHN), 1606, 1563, 1509, 1450, 1407, 1342, 1301, 1089, 986, 925,
904, 868, 837. Anal. Calcd for C19H23N: C, 85.99; H, 8.74; N, 5.28.
Found: C, 86.17; H, 8.60; N, 5.22.
N-(2-Adamantyl)-N-4-vinylbenzylideneamine (2). A benzene
(100 mL) solution of 4-formylstyrene (8.12 g, 61.1 mmol), 2-
adamantylamine hydrochloride (11.88 g, 63.4 mmol), and triethylamine
(100 mL) was refluxed for 4.5 h with azeotropic separation of water by
means of a Dean−Stark water trap (Scheme 1). The reaction mixture
was quenched with NaHCO3 solution, and the layer was separated. The
aqueous phase was extracted three times with diethyl ether. The
combined organic phase was dried over anhydrous MgSO4. After
evaporation of the solvent, the residue was purified by the
recrystallization from hexane to afford a white needle crystal (10.03 g,
37.8 mmol, 62%, mp = 123−124 °C). 1H and 13C NMR spectra of 2 are
shown in Figure S2. 1H NMR (300 MHz, CDCl3): δ = 1.52−1.55 (m,
2H, C(7)H, C(8)H), 1.80−1.93 (m, 10H, C(3)H2, C(4)H2, C(5)H2,
Figure S3a, respectively. 1H and 13C NMR spectra of poly(2) are shown
and Figure S5, respectively. The followings are the IR and EA data of
poly(1) and poly(2).
Poly(1). IR (KBr, cm−1): 3020, 2904, 2848, 1703, 1640 (CHN),
1607, 1571, 1508, 1451, 1419, 1307, 1173, 1089, 1016, 984, 925, 865,
826. Anal. Calcd for (C19H23N)n: C, 85.99; H, 8.74; N, 5.28. Found: C,
85.72; H, 9.89; N, 5.13.
Poly(2). IR (KBr, cm−1): 2900, 2848, 1645 (CHN), 1607, 1572,
1509, 1448, 1299, 1215, 1174, 1102, 1053, 1018, 962, 828. Anal. Calcd
for (C19H23N)n: C, 85.99; H, 8.74; N, 5.28. Found: C, 85.88; H, 8.72; N,
5.16.
Block Copolymerization of 1. The first-stage polymerization of 1
was performed with Ph2CHK in THF at −78 °C for 1 h in an all-glass
apparatus equipped with break-seals under high vacuum. After a small
portion of the poly(1) solution was sampled, tBMA in THF was added
to the residual living poly(1) in THF at −78 °C. The second-stage
polymerization of tBMA was continued for an additional 1 h to achieve
the complete conversion. The reaction solutions were terminated with
methanol and poured into methanol to afford a poly(1) and a poly(1)-b-
C
Macromolecules XXXX, XXX, XXX−XXX