Ring-Opening Polymerization of Lactones Catalyzed by Silicon-Based Lewis Acid

Table 2

Polymerization of cyclic monomers by 1a.

Run	Monomer	Time (h)	Yield (%)	Mn^a (kg/Mol)	Đ^a
19	δ-VL	1	>99	25	1.4
20		1/6	93	20	1.7
21^b		24	12	6	1.4
22^c		24	42	12	1.4
23	β-PL	1	24	1.8	1.5
24	β-BL	1	<1	—	—
25	ε-DL	1	<1	—	—
26	GL	1	<1	—	—
27	LLA	1	<1	—	—
28	TMC	1/6	99	21	1.6
29^d		24	26	7	2.3
30^e	DTC	1	22	7	2.0
31^f	PO	1	<1	—	—

Conditions: bulk polymerization, [M]₀ : [cat.] = 100 : 1, temp. = 100°C.
^aEstimated by GPC analysis calibrated with standard polystyrenes in THF.
^bSolution polymerization in toluene at [M]₀ = 0.62 mol/L.
^cSolution polymerization in toluene at [M]₀ = 0.82 mol/L.
^dSolution polymerization in toluene at [M]₀ = 0.41 mol/L.
^eTemp. = 120°C.
^fTemp. = 20°C.