Table 3. Chain extensions of atactic and isotactic pVEs with racemic and enantiopure thiiranes to generate BCPs with varying tacticities^a.

Entry	BCP	Monomer	Conv.g	M n h (kDa)	Đ h	T o i (°C)	T g j (°C)	T m j (°C)
1b	a-p(EVE)-b-a-p(POPS)	(rac)-POPS	76%	10.1	1.38	271, 373l	−30, 18l	—
2c	a-p(EVE)-b-iso-p(POPS)	(S)-POPS	67%	11.3	1.42	290, 382	−32, 20	118k
3d	iso-p(BnVE)-b-iso-p(PS)	(S)-PS	85%	16.2	1.41	284, 441	−30, −5	151
4e	a-p(IBVE)-b-a-p(PS)	(rac)-PS	36%	23.2	1.41	295, 398	−40, −18	—
5e	a-p(IBVE)-b-iso-p(PS)	(S)-PS	37%	22.5	1.40	298, 397	−38, −14	—
6f	iso-p(IBVE)-b-a-p(PS)	(rac)-PS	84%	41.3	1.29	298, 388	−39, −17	141
7f	iso-p(IBVE)-b-iso-p(PS)	(S)-PS	>99%	43.7	1.36	294, 406	−38, −17	138

^aStandard conditions: thiirane (50–200 eq.), pVE (1 eq.), Ph₄PCl (0.33 eq.), solvent, 60 °C, 6 h.

^bStarting a-p(EVE): M_n = 3.38 kDa, Đ = 1.33 (Table S1, entry 1). Used 50 eq. (rac)-POPS, 15 mM DMAc as solvent.

^cStarting a-p(EVE), M_n = 4.30 kDa, Đ = 1.31 (Table S1, entry 2). Used 50 eq. (S)-POPS, 15 mM DMAc as solvent.

^dStarting iso-p(BnVE), M_n = 7.71 kDa, Đ = 1.95 (Table S2, entry 3). Used 50 eq. (S)-PS, 5 mM 2 : 1 DMAc : THF as solvent.

^eStarting a-p(IBVE), M_n = 14.2 kDa, Đ = 1.27 (Table S1, entry 2). Used 200 eq. (rac)-PS, 5 mM 2 : 1 DMAc : THF as solvent.

^fStarting iso-p(IBVE), M_n = 19.8 kDa, Đ = 1.89 (Table S2, entry 5). Used 200 eq. (S)-PS, 5 mM 2 : 1 DMAc : THF as solvent.

^gDetermined via¹H NMR spectroscopy of the crude reaction mixture.

^hEntries 1 and 2: determined via SEC in DMF with 0.025 M LiBr calibrated against poly(methyl methacrylate) standards. Entries 3–7: determined via Waters SEC in THF calibrated against poly(styrene) standards.

ⁱCalculated from TGA thermograms.

^jDetermined by DSC using the 2^nd heat.

^kDetermined by DSC using the 1^st heat.

^lPreviously reported.³⁷