Studies on Fluorocarbon Elastomer Nanocomposites for Sealing Applications

The usage of seals in several applications like aircraft engines is mostly made of Fluorocarbon (FKM) elastomer. They are coloured products that enable easier identification based on the applications. In such seals, fillers like carbon black cannot be added to reinforce and improvise the mechanical properties since carbon black does not make it possible to add colours. The properties after ageing are also very critical in sealing application, and they must also be improved. Also, Nanocomposites are the modern and growing trends in the field of polymers that show enormous changes in the properties of the polymers without affecting their basic properties. So, the need for improvisation of FKM seals and the concept of Nanocomposites can be merged to form FKM Nanocomposites with Nano clay and Nano silica as the fillers. The objective of this project is to improve the mechanical properties, better retention of properties after ageing and after fluid interaction of the FKM seals with the aid of Nanofillers. Different proportions of FKM nanocomposites were prepared using modified Nano Kaolin Clay & modified Montmorillonite clay (Cloisite grades). Various mechanical properties like tensile strength, tensile modulus, elongation at break, compression set and tear strength etc., were studied. The test results have shown good improvements while increasing the filler loading. This is helpful to manufacture seals of desired colours thereby avoiding the difficulties faced in the carbon black-filled FKM compounds.

The Impact of Nano Clay on Normal and High-Performance Concrete Characteristics: A Review

The use of nano clay to improve the qualities of construction materials and engineering applications has attracted a lot of discussion in recent years. This review article summarizes the influence of nano clay as a cement substitute and supplement on the performance of conventional and high-performance concrete. The addition of nano clay to high performance concrete revealed an increase in compressive and flexural strength, as well as durability attributes such as resistance to elevated temperatures and sulfate attack, while simultaneously decreasing porosity, permeability, and water absorption. This enhancement is a result of nano clay’s roles as nano reinforcements, nanofillers, nucleation sites, and reactive pozzolans, which promote hydration and increase material characteristics.

MB Dye Adsorption Behavior on Poly (N cyclohexylacrylamide-co-Acrylamide/Maleicacid)/ OMMT Nanocomposite Hydrogels

A series of poly (N-cyclohexylacrylamide-co-Acrylamide/Maleic acid) /OMMT nanocomposite hydrogels (NC) were prepared from free-radical copolymerization in water/methanol medium using ammonium persulfate (APS) as a free radical initiator and N,N’- methylene-bis-acryl amide(MBA) as the cross-linker at 60˚C. The nanocomposite hydrogels were synthesized via in situ polymerization using organo modified MMT (O-MMT) nano clay. The optimum swelling of nanocomposite superabsorbents was achieved at 0.150g of OMMT nanoclay. The synthesized nanocomposites were characterized by FTIR, SEM, XRD and TGA techniques. Swelling and diffusion parameters in water and dye solution were calculated. The effect of two cationic salt solutions on the swelling was studied. The hydrogel nanocomposites showed up to 99.9% removal efficiency towards methylene blue dye adsorption study.

Adsorptive Capture of Ionic and Non-Ionic Pollutants Using a Versatile Hybrid Amphiphilic-Nanomica

A versatile, functional nanomaterial for the removal of ionic and non-ionic pollutants is presented in this work. For that purpose, the high charge mica Na-4-Mica was exchanged with the cationic surfactant (C16H33NH(CH3)2)+. The intercalation of the tertiary amine in the swellable nano-clay provides the optimal hydrophilic/hydrophobic nature in the bidimensional galleries of the nanomaterial responsible for the dual functionality. The organo-mica, made by functionalization with C16H33NH3+, was also synthesized for comparison purposes. Both samples were characterized by X-ray diffraction techniques and transmission electron microscopy. Then, the samples were exposed to a saturated atmosphere of cyclohexylamine for two days, and the adsorption capacity was evaluated by thermogravimetric measurements. Eu3+ cations served as a proof of concept for the adsorption of ionic pollutants in an aqueous solution. Optical measurements were used to identify the adsorption mechanism of Eu3+ cations, since Eu3+ emissions, including the relative intensity of different f–f transitions and the luminescence lifetime, can be used as an ideal spectroscopic probe to characterize the local environment. Finally, the stability of the amphiphilic hybrid nanomaterial after the adsorption was also tested.

A review of recently developed polymer composite materials for fused deposition modeling 3D printing

Additive Manufacturing (AM) is a rapidly evolving technology due to its numerous advantages over traditional manufacturing processes. AM processable materials are limited and have poor mechanical performance, restraining the technology's potential for functional part manufacturing. Although FDM is the most popular and growing technique, the inferiority of the material limits its application to prototyping. Nanocomposite material improves the thermal, mechanical, and electrical performance of FDM objects. Mostly polymer nanocomposites are feasible to process and several researchers have reported enhanced performance with polymer nanocomposites. Carbon nanotubes, graphene nanoplatelets, nano clay, and carbon fiber are primary reinforcements to thermoplastics. The current state of the art relevant to advances in nanocomposites for the FDM process, as well as the influence of nanofillers on mechanical properties of the build object are reviewed in this paper.

Polyhydroxybutyrate-Based Nanocomposites for Bone Tissue Engineering

Bone-related diseases have been increasing worldwide, and several nanocomposites have been used to treat them. Among several nanocomposites, polyhydroxybutyrate (PHB)-based nanocomposites are widely used in drug delivery and tissue engineering due to their excellent biocompatibility and biodegradability. However, PHB use in bone tissue engineering is limited due to its inadequate physicochemical and mechanical properties. In the present work, we synthesized PHB-based nanocomposites using a nanoblend and nano-clay with modified montmorillonite (MMT) as a filler. MMT was modified using trimethyl stearyl ammonium (TMSA). Nanoblend and nano-clay were fabricated using the solvent-casting technique. Inspection of the composite structure revealed that the basal spacing of the polymeric matrix material was significantly altered depending on the loading percentage of organically modified montmorillonite (OMMT) nano-clay. The PHB/OMMT nanocomposite displayed enhanced thermal stability and upper working temperature upon heating as compared to the pristine polymer. The dispersed (OMMT) nano-clay assisted in the formation of pores on the surface of the polymer. The pore size was proportional to the weight percentage of OMMT. Further morphological analysis of these blends was carried out through FESEM. The obtained nanocomposites exhibited augmented properties over neat PHB and could have an abundance of applications in the industry and medicinal sectors. In particular, improved porosity, non-immunogenic nature, and strong biocompatibility suggest their effective application in bone tissue engineering. Thus, PHB/OMMT nanocomposites are a promising candidate for 3D organ printing, lab-on-a-chip scaffold engineering, and bone tissue engineering.

Study of heat and sound insulation for polymeric composites reinforced with nano clay

Composite materials were prepared using epoxy as a matrix and nanoclay as a reinforcement with weight fractions 5% and 10%, using hand lay-up as a preparation technique. An unreinforced epoxy cast was also prepared for comparison. Heat and acoustic insulation were studied, in addition to tensile, compression, and impact tests. The results showed that the sound levels were the highest in the unreinforced specimen, and decreased gradually with nanoclay, suggesting that the nanoclay have impeded the path for sound waves transmission. The same behavior was observed with thermal conductivity. The tensile strength for the 5% wt. specimens were about 40% higher than that of the 10% wt. specimens, and about 60% higher than the unreinforced epoxy. The Young's modulus was 1.899 MPa, 3.25 MPa, and 4.143 MPa for the 5%, 10%, and unreinforced epoxy, respectively. Impact and compressive strengths were directly proportional with nano clay content. Scanning electron microscopy was used to reveal the microscopic details. The results prove that the addition of nanoparticles must be optimized to get the desired results.