N‐Hydroxyethylacrylamide (HEAA) was polymerized using the atom transfer radical polymerization (ATRP) with ethyl 2‐chloropropionate (ECP), copper(I) chloride (CuCl), and tris[2‐(dimethylamino)ethyl]amine (Me6TREN) in ethanol/water, producing poly(N‐hydroxyethylacrylamide) (PHEAA) with well‐defined molecular weights. The thermogravimetric analysis (TGA) indicated that the obtained PHEAA broadly decomposed with a two‐stage weight loss. The first loss was due to the decomposition of the hydroxyethyl groups, which started at temperatures ranging from 249.2 to 277.1 °C. The remaining polyacrylamide backbones started to decompose at temperatures ranging from 352.5 to 383.4 °C. The differential scanning calorimetry (DSC) indicated that PHEAA had a glass transition temperature (Tg) ranging from 70.6 to 117.8 °C. The ability of the obtained PHEAA as a prepolymer to initiate other acrylamide derivatives is described. N,N‐Dimethylacrylamide (DMAA), N‐acyloylmorpholine (NAM), and N‐[3‐(dimethylamino)propyl]acrylamide (DMAPAA) were subsequently added to the solutions after the polymerization of HEAA with ECP/CuCl/Me6TREN, producing the corresponding block copolymers.magnified image

1-Adamantyl methacrylate (AdMA) was polymerized using the atom transfer radical polymerization (ATRP) method with methyl a-bromoisobutyrate (MBiB), copper(I) bromide (CuBr), copper(II) bromide (CuBr 2 ) and 1,1,4,7,10,10-hexamethyltriethylenetetramine (HMTETA) in toluene at 60 1C, producing well-defined poly(1-adamantyl methacrylate) (PAdMA). Simultaneous control of the molecular weight and tacticity of PAdMA was successfully achieved by the ATRP method using the MBiB/CuBr/CuBr 2 / tris[2-(dimethylamino)ethyl]amine-initiating system in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) at À20 1C. Block copolymerization of AdMA and methyl methacrylate (MMA) was successfully achieved by the poly(methyl methacrylate) macroinitiator/CuBr 2 /HMTETA/tin(II) 2-ethylhexanoate-initiating system based on activators generated by electron transfer (AGET) ATRP method. Differential scanning calorimetry revealed the relationship between the glass transition temperature, molecular weight and tacticity of the obtained PAdMA.

We report a series of cyclopolymerizations of bis(4-vinylbenzoate) monomers through an atom transfer radical polymerization (ATRP) using chiral ligands. Cyclized polymers showing chiroptical properties were produced by polymerization of the racemic bifunctional monomer, rac-2,4-pentanediyl bis(4-vinylbenzoate) (rac-1), and enantiomerically unbalanced bifunctional monomers were recovered, providing substantial evidence for the enantiomer-selective polymerization of rac-1 mediated through the ATRP with chiral ligands. A comparison between the enantiomerically pure monomers, (2R,4R)-2,4-pentanediyl bis(4-vinylbenzoate) (RR-1) and (2S,4S)-2,4-pentanediyl bis(4-vinylbenzoate) (SS-1), revealed a drastic discrepancy in the rates of their homopolymerizations during the ATRP. The enantiomeric copolymerization of RR-1 and SS-1 indicated that the monomer reactivity ratio of RR-1 was higher than that of SS-1 for the ATRP with chiral ligands. The results of both homopolymerizations and copolymerizations clearly demonstrate the propensity for incorporation of the RR-1 enantiomer and thus the enantiomer-selective polymerization in this system. The monomer-structural effects on the enantiomer-selectivity were examined, and it was concluded that the chirality in the monomer is also essential for the enantiomer-selective polymerization as well as the chiral ligands for ATRP. Finally, the viability of the cyclopolymerization in the enantiomer-selective polymerization was proved using mono(4-vinylbenzoate) monomers incapable of cyclizing through the polymerization.

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