Liquid crystalline phases from polymer functionalized ferri-magnetic Fe₃O₄nanorods

Abstract

LC-phases from ferrimagnetic nanoparticles formed due to their anisotropy of form, and they can be modified using external magnetic fields.

Microfluidic Synthesis of Liquid Crystalline Elastomer Particle Transport Systems which Can Be Remote‐Controlled Magnetically

“…PMMA signals of functionalized particles could be visualized through IR spectroscopy (Figure S11, Supporting Information) (data of Figures S3–S11, Supporting Information are already published in ref. ).…”

“…Hereby, stable suspensions could be obtained, especially when the LC precursor monomers are heated into their isotropic phase. The reaction scheme to obtain PMMA functionalized magnetic nanoparticles (MNPs) is shown in Figure S2 (Supporting Information) and follows a previously described procedure . Reversible addition‐fragmentation chain transfer (RAFT) polymerization as a controlled radical polymerization type was chosen to obtain a diblock copolymer consisting of PMMA and an anchor block to bind on the oxidic surfaces of MNPs.…”

“…Afterward, this reactive ester block was transformed to a poly(dopamine acryl amide) (P(DOPA)) block through a polymer analogous reaction with dopamine. The introduced catechol groups are known to bind strongly to oxidic surfaces and thus are suitable for the functionalization of anisotropic Fe 3 O 4 nanoparticles . All reactions were monitored with 1 H‐NMR spectroscopy and 19 F‐NMR spectroscopy (Figures S3–S5, Supporting Information).…”

“…Materials and Reagents : The liquid crystalline monomer (4′‐acryloyloxybutyl 2,5‐di(4′‐butyloxybenzoyloxy)benzoate), the liquid crystalline azobenzene monomer (4‐butoxy‐2′‐(4‐methacryloyloxybutoxy)‐4′‐(4‐butoxybenzoyloxy)azobenzene), the comonomer (4′‐acryloyloxybutyl 2,5‐di(4′‐pentylcyclohexyloyloxy)benzoate), the liquid crystalline crosslinker (1,4‐bis (4‐(6′‐acryloxy‐hexyloxy)benzoyloxy)‐2‐toluene), the dye for the initiator (1,3,3,1′,3′,3′‐hexamethyl‐11‐chloro‐10,12‐propylene‐tricarbocyanine iodide), the Fe 3 O 4 nanorods, P(MMA‐b‐DOPA) ( M n,GPC : 17 000 g mol −1 , M w M n −1 = 1.08) and P(MMA‐b‐DOPA) functionalized Fe 3 O 4 nanorods were synthesized as described in the literature.…”

Magnetic field induced uniaxial alignment of the lyotropic liquid-crystalline PMMA-grafted Fe3O4 nanoplates with controllable interparticle interaction

“…Thus, PMMA-modied Fe 3 O 4 NPs are expected to show promise in the exploitation of various functions in magnetorheological and magnetic uids, electrochemical sensors, and lyotropic liquid crystals (LCs). [37][38][39][40] In particular, magnetorheological uids (MR uids), as a type of magnetic suspension whose viscosity increases dramatically in the presence of an external magnetic elds, have potential application in some smart devices. 41 On the other hand, ionic liquids, as organic solvents, can mix well with PMMA-modied inorganic NPs and exhibit unique rheological and optical properties.…”