Supplementary Information

Synthetic Procedures for Monobenzyl -Carboxyalkanoyl Chlorides

Synthesis of monobenzyl adipate

Monobenzyl adipate was prepared according to the procedure of Kar (Kar et al. 2011). Adipic acid (73 g, 0.5 mol), benzyl alcohol (81 g, 0.75 mol), PTSA (0.95 g, 5 mmol), and toluene (200 mL) were combined in a one neck flask equipped with a Dean-Stark trap, and the resulting solution was heated at reflux for approximately 4 h. The mixture was heated (above 110°C) until the theoretical amount of H2O (13.5 mL, 0.75 mol) was obtained from the Fischer esterification of adipic acid. The solution was then cooled to room temperature, 200 mL of H2O was added, and the pH was adjusted to 9.0 with 6N NaOH. The aqueous layer was separated and washed with ether (2 X 100 mL), then 200 mL of ethyl ether was added, and the pH of the aqueous layer was adjusted to 2.0 with 6N HCl. The ether layer was separated, and washed with 50 mL of 1M NaHCO3 for 15 min. Then the ether layer was separated, concentrated under reduced pressure, and filtered. Monobenzyl adipate (41 % yield) was dried under vacuum at 40°C as a colorless oil: 1H NMR (CDCl3): 1.68 (m, 4 H), 2.36 (m, 4 H), 5.09 (s, 2 H), and 7.32 (m, 5 H).

Similar protocols were followed to synthesize monobenzyl sebacate (white solid, yield 31.35 g, 0.12 mol, 19% yield) and monobenzyl suberate (colorless oil, yield 16.96 g, 0.058 mol, 24% yield).

1H NMR of monobenzyl suberate. (CDCl3): 1.33 (m, 4H), 1.63 (m, 4H), 2.33 (m, 4H), 5.11 (s, 2H), 7.34 (m, 5H).

1H NMR of monobenzyl sebacate (CDCl3): 1.29 (m, 8H), 1.62 (m, 4H), 2.33 (m, 4H), 5.11 (s, 2H), 7.35 (m, 5H).

2.2.3 Synthesis of monobenzyl adipoyl chloride

Monobenzyl adipoyl chloride was prepared according to Liu (Kar et al. 2011; Liu et al. 2014). Monobenzyl adipate (0.068 mol, 15.00 g) was dissolved in dichloromethane (300 mL) in a one-neck flask while stirring, then 5 drops of DMF was added. The solution was cooled in an ice bath to 0°C and oxalyl chloride (24.42 mL, 5.6 eq) was added slowly via an addition funnel. The ice bath was then removed and the solution stirred at room temperature. Completion of gas formation indicated the end of the reaction, at which point the solvent was removed under reduced pressure. Toluene (15 mL) was added and the product was concentrated again under reduced pressure at 50°C for 1 h. Yield: 90% (0.04 mol, 13.5 g). 1H NMR (CDCl3): 1.73 (m, 4 H), 2.39 (t, 2 H), 2.90 (t, 2 H), 5.12 (s, 2 H), 7.32 (m, 5 H).

Similar procedures were followed to synthesize monobenzyl sebacoyl and monobenzyl suberoyl chlorides.

Monobenzyl sebacoyl chloride. Yield: 95% (0.046 mol, 14.35 g). 1H NMR (CDCl3): 1.30 (m, 8H), 1.67 (m, 4H), 2.35 (t, 2H), 2.86 (t, 2H), 5.11 (s, 2H), 7.35 (m, 5H).

Monobenzyl suberoyl chloride. Yield: 90% (0.051 mol, 14.54 g). 1H NMR (CDCl3): 1.34 (m, 4H), 1.66 (m, 4H), 2.36 (t, 2H), 2.86 (t, 2H), 5.12 (s, 2H), 7.35 (m, 5H).

Table S1 shows how the solubility parameter was calculated for the methyl cellulose adipate polymer, and Figure 1 is a schematic of the groups that are affected by DS and the ones that are not.

Table S1: Solubility parameter calculation for methyl cellulose adipate

Group / Number of groups / E (cal*mol-1) / / V (cm3*mol-1) /
a / b / Total
-CH3 / 0 / 1.86 / 1.86 / 1125 / 2092 / 33.5 / 62.3
-CH2 / 1 / 4.40 / 5.40 / 1180 / 6372 / 16.1 / 86.9
-CH / 5 / 0 / 5.00 / 820 / 4100 / -1 / -5
Ring closurec / 1 / 0 / 1 / 250 / 250 / 16 / 16
-OH / 0 / 0.04 / 0.04 / 7120 / 285 / 10 / 0.4
-O- / 2 / 1.86 / 3.86 / 800 / 3088 / 3.8 / 14.7
-COOH / 0 / 1.10 / 1.10 / 6600 / 7260 / 28.5 / 31.4
-CO2 / 0 / 1.10 / 1.10 / 4300 / 4730 / 18 / 19.8
Correctiond / - / - / - / - / - / - / 14.0
Total / - / - / - / - / 28177 / 240.5
Solubility Parameter (MPa1/2) / 22.14

aConstant number of groups for all cellulose based polymers

bIt will change depending on DS for different substituents

cRing closure (5 or more atoms)

dCorrection when Tg > 25˚C

Figure S1: Schematic for SP calculation. The groups in green are not affected by the DS and are constant for diverse cellulose based polymers: 1 ring closure, 5 -CH, 1 -CH2 and 2 –O–. The groups in red will change depending on the DS for each polymer: OR.

Figure S2: 1H-NMR of monobenzyl adipoyl chloride

Table S2: Detailed SEC results.

Ref. No. / Ether type / Ester type / Mn / Poly dispersity / *Calculated Mw / DP
1 / EC / Adipate / 10000 / 1.45 / 296.6 / 34
2 / EC / Suberate / 9000 / 1.50 / 310.1 / 29
3 / EC / Sebacate / 10000 / 1.48 / 326.8 / 31
4 / MC / Benzyl Adipate / 82600 / 4.23 / 386.0 / 213
5 / MC / Benzyl Suberate / 69596 / 3.62 / 416.9 / 167
6 / MC / Benzyl Sebacate / 122319 / 4.9 / 424.1 / 288
  • Molecular weight is calculated according to the degree of substitution.

Figure S3: 13C NMR of benzyl MCSeb in d6-acetone.

Figure S4:13CNMR of benzyl ECAd in d6-DMSO.

Figure S5: 13CNMR of benzyl ECSub in d6-acetone.

Figure S6: 13CNMR of benzyl MCSub in d6-DMSO.

Figure S7: FTIR spectra of MC (blue) and MCAd (Red).

Figure S8: FTIR spectra of MCSub (blue) and MCSeb (Red).

Figure S9: DSC thermogram of ECAd.