Self-assembly of L-proline functional thermoresponsive double hydrophlic block copolymers for aldol reaction in water: the influence of POEGA block content

The self-assembly of L-proline functional thermoresponsive double hydrophlic block copolymers (DHBCs) can effectively catalyze aldol reaction in water. Considering the block content of copolymers influences the assemblies and catalytic activities, thermoresponsive DHBCs supported L-proline P(NIPAm- co -ProlA)- b -POEGA with different POEGA block content were prepared by reversible addition fragmentation chain transfer (RAFT) polymerization. The therm-triggered self-assemblies were investigated by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Then, the resultant assemblies were used as catalysts for the aldol reaction with cyclohexanone and 4-nitrobenzaldehyde as substrates. The results indicated that P(NIPAm- co -ProlA)- b -POEGA with ca. 18 mol% of POEGA can form stable catalytic system, which maintained high selectivity and productivity of product, accompanied with satisfactory reusability.