Table 2 Summarized data for the copolymerization reactions of α-substituted acrylates with β-substituted acrylates^a

Entry	M¹	M²	Initiator	Catalyst	Solvent	[M¹]₀	[M²]₀	Time	x^{1 d}	x^{2 d}	Yield^e	M_n^f	Đ^f	f ^g
			mmol	mmol	mL	mol L⁻¹	mol L⁻¹	h	%	%	%	g mol⁻¹	M_w/M_n	%
10	MMA	MC	0.025	0.025	8.9	1.0	–	24 + 24	78	81	72	58,300^h	1.27^h	55
11	MMA	nBC	0.025	0.025	8.7	1.0	–	24 + 24	79	97	81	77,000^h	1.25^h	56
12	nBMA	MC	0.025	0.025	8.7	1.0	–	24 + 24	73	70	56	57,600^h	1.24^h	60
13	nBMA	nBC	0.025	0.025	8.4	1.0	–	24 + 24	78	100	84	68,200^h	1.23^h	75
14	nBMA	MC	0.025	0.025	8.7	1.0	–	12 + 24	51	92	59	56,300	1.21	59
15	nBMA	MCin	0.100	0.100	6.3	1.0	–	6 + 162	100	38	67	16,800	1.17	61
16^b	MC	nBMA	0.025	0.025	8.7	1.0	–	24 + 24	100	4	40	49,300	1.11	43
17^c	nBMA	MC	0.025	0.025	8.7	0.50	0.50	48	6	90	35	46,700	1.16	42

^aPerformed on an aluminum block at 0 °C under an argon atmosphere. The polymerization conditions were as follows: M¹ feed and M² feed = 5.0 mmol, initiator = ^tBuMe2SKA, catalyst = Tf₂NSi^tBuMe₂ (generated via the in situ reaction between ^tBuMe2SKA and Tf₂NH (Scheme S1, Supporting Information)), solvent = CH₂Cl₂. Two-stage polymerization was conducted. M¹ was homopolymerized in the first stage, and then a second feed of M² was added to the polymerization system
^bMC was used as M¹, and nBMA was used as M²
^cM¹ and M² were fed simultaneously into the polymerization system
^dMonomer conversions (x¹ = M¹ conv., x² = M² conv.) were calculated directly using ¹H NMR measurements (500 MHz, rt, CDCl₃) of the reaction mixture
^eThe polymer yield was calculated based on the total weight of the feed monomers (M¹ and M²)
^fThe number-averaged molecular weight (M_n) and dispersity (Đ) were determined using conventional GPC against PSt standards in CHCl₃
^gInitiator efficiency: f = [molecular weight of polymer calculated by a feed ratio]/[number-average molecular weight of polymers determined by GPC]
^hBimodal in GPC as for entries 10–13

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