A one-step synthesis of nanotubes by RAFT dispersion polymerization of cyclodextrin/styrene (CD/St) complexes directly in water is presented. The resulted amphiphilic PEG-b-PS diblock copolymers self-assemble in situ into nanoparticles with various morphologies. Spheres, worms, lamellae, and nanotubes were controllably obtained. Because of the complexation, the swelling degree of polystyrene (PS) blocks by free St is limited, resulting in limited mobility of PS chains. Consequently, kinetically trapped lamellae and nanotubes were obtained instead of spherical vesicles. During the formation of nanotubes, small vesicles first formed at the ends of the tape-like lamellae, then grew and fused into nanotubes with a limited chain rearrangement. The introduction of a host-guest interaction based on CDs enables the aqueous dispersion polymerization of water-immiscible monomers, and produces kinetically trapped nanostructures, which could be a powerful technique for nanomaterials synthesis.

The compounds (1Àx)PbTiO 3 -xBi(Mg,Ti) 1/2 O 3 (x ¼ 0-0.7) were prepared in order to hunt for low thermal expansion piezoceramics, in particular for zero thermal expansion over a wide temperature range. The negative thermal expansion of PbTiO 3 was much weakened by forming a solid solution with Bi(Mg,Ti) 1/2 O 3 . Solutions of (1Àx)PbTiO 3 -xBi(Mg,Ti) 1/2 O 3 with x ¼ 0.2 and x ¼ 0.4 exhibited zero thermal expansion covering a wide temperature range (from RT to about 500 C). The (1Àx)PbTiO 3 -xBi(Mg,Ti) 1/2 O 3 ceramics had high density and their mechanical performances were satisfactory with high fracture toughness. The promising applications of the zero thermal expansion materials (1Àx)PbTiO 3 -xBi(Mg,Ti) 1/2 O 3 are due to its high piezoelectric d 33 , controllable thermal expansion, and high thermal stability.

Using isotropic diblock copolymer spheres, polymerization-induced particle-assembly directly produces colloidal molecules.

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The reversible addition-fragmentation chain transfer (RAFT) mediated polymerization-induced self-assembly (PISA) enables efficient and convenient syntheses of polymeric nanoparticles, generally based on thermal initiation. However, the thermal initiation confines the incoporation...