Synthesis and Characterization of Star Graft Copolymers
with Asymmetric Mixed “V-shaped” Side Chains via
“Click” Chemistry on a Hyperbranched Polyglycerol
Core
Guowei Wang, Chao Liu, Mugang Pan, and Junlian Huang*
The Key Laboratory of Molecular Engineering of Polymer, State Education Ministry of China,
Department of Macromolecular Science, Fudan University, Shanghai 200433, China
Corresponding author: Junlian Huang; Email: jlhuang@fudan.edu.cn
Supporting Information
The Funtionalization Efficiency of “V-shaped” Side Chain and Its Intermediates.
PS-EEGE: The efficiency of functionalization (E.F.) was determined by 1H NMR in CDCl3 using the
formula: E.F. = [(3×A4.65-4.76)/A0.80]×100% = 97.3%. Where A4.65-4.76 was the intergral area of the ω’ethoxyethyl group proton (–OCH(CH3)O–) at 4.65-4.76 ppm, A0.80 was the intergral area of methyl
group protons (CH3CH2–) at 0.80 ppm. (Figure 1(A))
PS-alkyne-EEGE: E.F. was determined by 1H NMR in CDCl3 using the formula: E.F. = [A3.844.18/(2×A4.65-4.76)]×100%
= 98.9%. Where A4.65-4.76 was the intergral area of the ω’-ethoxyethyl group
proton (–OCH(CH3)O–) at 4.65-4.76 ppm, A3.84-4.18 was the intergral area of methylene group protons (–
OCH2C≡CH) at 3.84-4.18 ppm. (Figure 1(B))
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PS-alkyne-OH: E.F. was determined by 1H NMR in CDCl3 according to the complete hydrolysis for
the acetal group at the end of PS-alkyne-EEGE where the ω’-ethoxyethyl group proton (–OCH(CH3)O–)
at 4.65-4.76 ppm of PS-alkyne-EEGE fully disappeared. (Figure 2(A))
PS-alkyne-Br: E.F. was determined by 1H NMR in CDCl3 using the formula: E.F. = [(3×A3.84–
4.18)/(4×A0.80×E.F.(PS-EEGE))]×100%-E.F.(PS-alkyne-EEGE)
= 96.6%. Where A0.80 was the intergral area of
methyl group protons (CH3CH2–) at 0.80 ppm, A3.84–4.18 was the intergral area of methylene group
protons (–CH2COO–) and methylene group protons ( –OCH2C≡CH). (Figure 2(B))
The Mn(NMR) of PS-alkyne-PtBA. The Mn(NMR) of PS-alkyne-PtBA was determined by 1H NMR
in CDCl3 according to the formula: Mn(NMR) = [(5×A2.08-2.47×2,300×128)/(A6.30-7.30×104)]+ 2,300 =
5,300. Where A2.08-2.47 was the intergral area of methine group proton (–CH2CH–) on PtBA, A6.30-7.30
was the intergral area of aromatic group protons (–C6H5) on PS. The value of 128, 104 and 2,300 were
the molecular weight of tBA, St and Mn(GPC) of PS-EEGE respectively. (Figure 6(A))
Esterification Degree and Mn(NMR) of HPG-g-Br. The degree of esterification (D.E.) was
calculated by two ways. D.E.(1) = (A1.93×5)/(A3.1-5.5×6)×100% = 100%. Where A1.93 was the intergral
area of methyl groups protons (–C(CH3)2–Br) at 1.93 ppm, A3.1-5.5 was the intergral area of methylene
and methine groups protons on HPG core. D.E.(2) = [A5.25+A5.12+(A4.50+A4.34+A4.18)/2]×5/A3.15.5×100%
= 97.5%. Where A5.25 and A5.12 were the intergral area of methine group proton close to the
ester bond (Br–C(CH3)2–COO–CH–) on HPG at 5.25 and 5.12 ppm, A4.50, A4.34 and A4.18 were the
intergral area of methylene group protons close to the ester bond (Br–C(CH3)2–COO–CH2–) at 4.50,
4.34 and 4.18 respectively. A3.1-5.5 was the intergral area of methylene and methine groups protons on
HPG core. (Figure 4(B)) The full esterification means each unit on HPG was reacted with 2bromoisobutyryl bromide.
Thus the Mn(NMR) of HPG-g-Br could be calculated by the following formula: Mn(NMR) = 400×223
= 89,200. Where 400 and 223 were the number and molecular weight of the repeating units 2bromoisobutyryl glycerol.
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Mn(NMR) of HPG-g-N3. As we mentioned in the article, the bromide groups were fully transformed
into azide groups, so Mn(NMR) of HPG-g-N3 was calculated by the following formula: Mn(NMR) =
400×185 = 74,000. Where 400 and 185 were the number and molecular weight of the repeating units.
(Figure 6(B))
Mn(NMR) of HPG-g-PS/PtBA. The Mn(NMR) of HPG-g-N3 was calculated by the following
formula: Mn(NMR) = [(A6.30-7.30×104×74,000)/(A3.1-5.5×74)]×(5,300/2,300)+74,000. Where A6.30-7.30
was the intergral area of aromatic group protons (–C6H5) on PS, A3.1-5.5 was the intergral area of
methylene and methine groups protons on HPG core. 104 and 74 were the molecular weight of St and
glycerol, 74,000, 5,300 and 2,300 were the Mn(HPG-g-N3), Mn(NMR) of PS-alkyne-PtBA and Mn(GPC)
of PS-EEGE, respectively.
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