A unique polymersome covered by loop-cluster polyamine corona

In this work, we synthesized a new comb-like copolymer (c-iMP) possessing amphiphilic diblock side chains consisting of poly(methyloxazoline) (PMOZ) and poly(phenyloxazoline) (PPOZ) via reversible addition-fragmentation chain-transfer (RAFT) polymerization of p -choloromethylstyene (CMS) and cationic ring-opening polymerization (CROP) of 2-methyl-2-oxazoline (MOZ) and 2-phenyl-2-oxazoline (POZ). Then, by performing selective hydrolysis of the hydrophilic PMOZ block, the PMOZ block was transformed into PEI (polyethylenimine) from which comb-like copolymers (c-iEP) possessing two blocks of PEI (E) and PPOZ (P) were produced. The comb-copolymers c-iEP showed unique self-assembling behavior in water to give an unusual polymersome covered by a loop-cluster polyamine corona. The polymersome showed extreme toughness and stability without collapse and fusion even at dry conditions and could be transformed into capsules. This is the first example of polymesome without free-ends on the vesicle wall which could include Ag ions inside and could deposit silica around the wall to form hybrid hollow spheres. The comb with teeth of amphiphilic block copolymer possessing hydrophilic polyethyleneimine (inside) and hydrophobic poly(2-phenyl-2-oxazoline) (outside) self-assembled into extremely stable loop-cluster covered polymersome with very thin vesicular wall ( ca. 3 nm).