Generation of nanocomposites based on polystyrene-grafted CdSe nanoparticles by grafting through and block copolymer

Abstract

Continuing with our previous work, in which CdSe nanoparticles were functionalized with polystyrene (PS) brushes (CdSe-PS) by grafting through method, nanocomposites 2 were prepared by adding them to a poly (styrene-b-butadiene-b-styrene) (SBS) triblock copolymer. After characterizing CdSe-PS nanoparticles obtained at different polymerization times of 3, 5 and 8 h by means of thermogravimetric analysis (TGA) and gel permeation chromatography (GPC), CdSe-PS nanoparticles obtained after 5 h of polymerization (CdSe-PS(5h)) were chosen as the most adequate for the generation of nanocomposites. Atomic force microscopy (AFM) was used for morphological characterization of SBS/CdSe-PS (5h) nanocomposites. AFM images showed a good dispersion of the nanoparticles in the block copolymer, with the placement of the nanoparticles in the PS domains due to the improved affinity obtained by their functionalization with PS brushes.

Self-Assembly of Diblock Copolymer–Maghemite Nanoparticle Hybrid Thin Films

“…Particularly, applications using maghemite NPs (γ-Fe 2 O 3 ) profit from the low magnetic remanence and coercivity compared with those of bulk magnetic material, such as in medical applications and high-density memory devices. ,, Diblock copolymers (DBCs) are powerful and promising tools for the manufacture of diverse nanoscale ordered structures via a low-cost, highly efficient self-assembly method. , The tuning of the polymer domain spacing in the range of 10–100 nm can be achieved by selecting the molecular weight and the chemistry of the polymer blocks . An ordered, highly periodic polymer template is essential for producing well-defined metal oxide–polymer nanocomposites. − Employing the selective metal oxide NP deposition in one block of the DBC films enables a highly ordered metal oxide NP distribution within the polymer film. Both enthalpic and entropic interactions, such as metal oxide–metal oxide interactions play important roles on the overall spatial distribution of the metal oxide NPs within the polymer matrix. , Morphological modifications of the nanostructured DBC films upon incorporation of the metal NPs has been reported .…”

Enhanced Ordering of Block Copolymer Thin Films upon Addition of Magnetic Nanoparticles

“…This makes the fabrication of homogeneous nanocomposites with uniform distribution of the NPs localized inside the desired copolymer block quite challenging. Among the diverse ways to improve the affinity of nanoparticles toward individual polymer blocks, the chemical surface modification approach is gaining considerable attention. , Grafting different organic ligands, such as oleic acid, polymer chains, and silane groups, to NPs was proven to increase the spatial repulsion between the NPs and thus decrease the tendency to agglomeration, as well as enhance the selectivity of NPs to the desired block of the copolymer. − However, existing studies have been predominantly focused on manipulating with relatively weak NP interactions, such as van der Waals interactions between nanoparticles shell and one of the copolymer blocks . Increasing favorable enthalpic interactions between BCPs and nanoparticles (i.e., hydrogen-bonding or ionic interactions) not only improves the nanoparticles distribution within the polymeric matrix but also allows us to tune the microphase-separated morphologies of BCPs .…”

Production and characterization of novel nanocomposites based on poly(amide‐imide) containing N‐trimellitylimido‐l‐alanine diacid and 4,4′‐diaminodiphenylmethan segments reinforced with grafted nano‐ZnO by citric acid as a biological ligand

“…They have attracted increasing attention due to their improved properties compared with the conventional materials and have also advantages of polymers such as high homogeneity, flexibility, and conformity . The NCs have vast potential for different applications such as packaging, sporting goods, and electrical applications .…”