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Millions of people across the globe are severely afflicted because of water potability issues, and to proffer a solution to this crisis, efficient and cost-effective desalination techniques are necessitated. Membranes, in particular Graphene-derived membranes, have emerged as a potential answer to this grave problem because of their tunable ionic and molecular sieving capability, thin structure, and customizable microstructure. Among graphene-derived membranes, Graphene Oxide membranes have been the most promising, given the replete presence of oxygen-containing functional groups on its surface. However, the prospects of commercial applicability of these membranes are currently plagued by uneven stacking, crossflow delamination, flawed pores, screening and pH effects, and horizontal defects in the membrane. In addition, due to the selectivity–permeability trade-off that commonly exists in all membranes, the separation efficiency is negatively influenced. This review, while studying these challenges, aims to outline the most recent ground-breaking developments in graphene-based membrane technology, encompassing their separation mechanism, selectivity, adjustable mechanical characteristics, and uses. Additionally, we have covered in detail how several process variables such as temperature, total oxygen concentration, and functional groups affect the effectiveness of membrane separation with the focal point tilted toward studying the currently used intercalation techniques and effective nanomaterial graphene oxide membranes for water desalination

 

Structurally well-defined polymer-grafted nanoparticle hybrids are highly sought after for a variety of applications, such as antifouling, mechanical reinforcement, separations, and sensing. Herein, we report the synthesis of poly(methyl methacrylate) grafted- and poly(styrene) grafted-BaTiO3 nanoparticles using activator regeneration via electron transfer (ARGET ATRP) with a sacrificial initiator, atom transfer radical polymerization (normal ATRP), and ATRP with sacrificial initiator, to understand the role of the polymerization procedure in influencing the structure of nanoparticle hybrids. Irrespective of the polymerization procedure adopted for the synthesis of nanoparticle hybrids, we noticed PS grafted on the nanoparticles showed moderation in molecular weight and graft density (ranging from 30,400 to 83,900 g/mol and 0.122 to 0.067 chain/nm2) compared to PMMA-grafted nanoparticles (ranging from 44,620 to 230,000 g/mol and 0.071 to 0.015 chain/nm2). Reducing the polymerization time during ATRP has a significant impact on the molecular weight of polymer brushes grafted on the nanoparticles. PMMA-grafted nanoparticles synthesized using ATRP had lower graft density and considerably higher molecular weight compared to PS-grafted nanoparticles. However, the addition of a sacrificial initiator during ATRP resulted in moderation of the molecular weight and graft density of PMMA-grafted nanoparticles. The use of a sacrificial initiator along with ARGET offered the best control in achieving lower molecular weight and narrow dispersity for both PS (37,870 g/mol and PDI of 1.259) and PMMA (44,620 g/mol and PDI of 1.263) nanoparticle hybrid systems. 

The block copolymer (BCP) phase separation is an intriguing phenomenon, the dynamics of which can be expected to differ significantly from that of the polymer blends due to the chain connectivity constraints. The BCP phase separation dynamics has been studied theoretically, but there has been little experimental evidence to confirm the BCP domain growth scaling laws put forward by theoretical studies. Here, we demonstrate the dynamics of late-stage lamellar BCP domain coarsening and show that the scaling exponent for domain growth is ≈1/6 (0.17) irrespective of the annealing temperature, which is close to the scaling exponent of 0.2 shown by theoretical studies. Furthermore, we show that the pre-factors in the domain coarsening equation show Arrhenius dependence on temperature indicating that the BCP domain growth dynamics is Arrhenius. 

The synthesis of polymer-grafted nanoparticles (PGNPs) or hairy nanoparticles (HNPs) by tethering of polymer chains to the surface of nanoparticles is an important technique to obtain nanostructured hybrid materials that have been widely used in the formulation of advanced polymer nanocomposites. Ceramic-based polymer nanocomposites integrate key attributes of polymer and ceramic nanomaterial to improve the dielectric properties such as breakdown strength, energy density and dielectric loss. This review describes the ”grafting from” and ”grafting to” approaches commonly adopted to graft polymer chains on NPs pertaining to nano-dielectrics. The article also covers various surface initiated controlled radical polymerization techniques, along with templated approaches for grafting of polymer chains onto SiO2, TiO2, BaTiO3, and Al2O3 nanomaterials. As a look towards applications, an outlook on high-performance polymer nanocomposite capacitors for the design of high energy density pulsed power thin-film capacitors is also presented.