Synthesis of Block Copolymers by Atom Transfer Radical Polymerization, ATRP

Synthesis of Block Copolymers by Atom Transfer Radical Polymerization, ATRP 

The polymerization of 2-(diethylamino)ethyl methacrylate, DEAEMA, was studied under different conditions. It was shown that the best system providing narrow molecular weight distribution polymers involved the use of p-toluenesulfonyl chloride/CuCl/HMTETA as the iniliator/catalyst/ligand at 60 °C in methanol [72]. Taking advantage of these results, well-defined PDEAEMA-b-PfBuMA block copolymers were obtained. The synthesis was successful when either fBuMA or DEAEMA was polymerized first. Poor results with bimodal distributions were obtained when CuBr was used as the catalyst. This behavior was attributed to the poor blocking efficiency of PDEAEMA-Br and the incomplete functionahzation of the macroinitiator. 

A novel coil-rod-coil triblock copolymer, where the rod block was polyfluorene, PF, and the coil blocks poly(2-tetrahydropyranyl methacrylate). 

A half-metallocene iron iodide carbonyl complex Fe(Cp)l(CO)2 was found to induce the hving radical polymerization of methyl acrylate and f-butyl acrylate with an iodide initiator (CH3)2C(CO2Et)l and Al(Oi- Pr)3 to provide controlled molecular weights and rather low molecular weight distributions (Mw/Mn 1.2) [79]. The hving character of the polymerization was further tested with the synthesis of the PMA-fo-PS and PtBuA-fi-PS block copolymers. The procedure efficiently provided the desired block copolymers, albeit with low molecular weights. 

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