Controllable Synthesis Of Amphiphilic Block Copolymer Pmneos-B-Paa And Co-Assembly Morphologies Of Pmdeos-B-Paa/Ps-B-Paa

The co-assembly of polymers has attracted increasing attention due to the ability of generating diverse assembly morphology. This paper describes the synthesis and self-assembly of several novel amphiphilic block copolymers (PMnEOS-b-PAA, n=1-3) as well as co-assembly of PMDEOS-b-PAA with typical polystyrene-b-polyacrylic acid (PS-b-PAA). Namely, these block copolymers were fabricated by reversible addition fragmentation chain transfer (RAFT) polymerization of functionalized styrene bearing different glycol units on the para-position and acrylic acid, and characterized by H-1 nuclear magnetic resonance spectrum (H-1 NMR). The thermo-responsive and pH-responsive properties of these block copolymers were then investigated, and they showed good thermo- and pH- responsiveness. Furthermore, as a comparison, the self-assembly actions of these block copolymers were also examined in tetrahydrofuran (THF)/H2O and THF/toluene (PhMe) , respectively. It was found that the different block copolymers with different glycol units displayed various morphologies, especially in two different solvent systems. More interestingly, the co-assembly action of PMDEOS-b-PAA/PS-b-PAA( mass ratio 1: 1) in a mixture of THF-PhMe( volume ratio 2: 1) was detaily studied and a new spherical nanoparticle with uniformly distributed internal channel and smooth surface was found. Also, this coassembly morphology could be well repeated. The corresponding self- and co-assembly mechanisms were also proposed. This novel co-assembly mode would have potential application for further supporting catalysts, small molecules recognition and release in industry.