Enhancing material performance of Chloroprene rubber (CR) by strategic incorporation of zirconia

Chloroprene rubber (CR) composites, embedded with a well dispersed zirconia, within it’s matrix are produced that combine superior reinforcement of zirconia with the other useful composite properties. The in-situ incorporated...

Reinforcement of Montmorillonite Clay in Epoxy/Unsaturated Polyester Blended Composite: Effect on Composite Properties

Montmorillonite (MMT) clay was disseminated into Unsaturated Polyester (UP) and Epoxy blend systems in diverse weight ratios namely, 0, 1, 2, 3, and 5% to prepare Epoxy/UP/MMT clay composite. The specimen was characterized by thermal and chemical analysis. Homogeneous mixture of blended composites is obtained through mechanical stirring and ultrasonication processes. The testing of thermal and chemical properties was performed. Evidence acquired from the above tests indicate that Epoxy reinforced with UP and further strengthened with MMT clay enhanced the thermal and chemical properties of the composite to a considerable extent. The purpose of this study was to recognize an appropriate composite offering a stronger material with enhanced performance; that is suitable for diverse industrial uses.

Study of Thermal, Mechanical and Barrier Properties of Biodegradable PLA/PBAT Films with Highly Oriented MMT

In order to improve the properties of biodegradable polylactide (PLA), mixtures with polybutylene adipate-co-terephthalate (PBAT) were prepared. PLA is a bio-based and renewable biodegradable material, made from starch. PBAT is a biodegradable polyester for compostable film. In order to improve the composite properties, two types of additives were implemented via melt mixing, a chain extender (CE) and montmorillonite (MMT). CE was used as an interfacial modifier to enhance the adhesion between components. Montmorillonite is a widely studied clay added to polymer nanocomposites. Due to the lamellar structure, it improves the barrier properties of materials. PLA/PBAT films were oriented in the extrusion process and the amounts of filler introduced into the PLA/PBAT nanocomposites were 1.0, 3.0, and 5.0%. The improvement in the PLA barrier properties by the addition of PBAT and 5% of MMT was confirmed as the oxygen permeability decreased almost by a factor of 3. The addition of the biodegradable polymer, chain extender, montmorillonite, and the implemented orientation process resulted in a decrease in composite viscosity and an increase in the PLA crystallinity percentage (up to 25%), and the wettability tests confirmed the synergic behavior of the selected polymer blend.

Study on The Characteristics of NaCl Treated Kenaf Fiber Epoxy Composite Board

The treatment of kenaf fiber surfaces with chemicals has proven to be an effective method to improve composite properties. Meanwhile, natrium chloride (NaCl) is one of the chemicals that has great potential to be used for modifying natural fibers. Therefore, this study aims to investigate the characteristics of a composite board made from NaCl-treated kenaf fiber and epoxy. The method used was a completely randomized design with two factors, namely the level of NaCl in the treatment solution including 1, 3, and 5%wt, as well as the epoxy content of 10, 20, and 30%wt based on the dry weight fiber. The NaCl treatment was carried out by soaking the fibers in the solution for 1 hour at room temperature, rinsed using water until the pH of the water reached 7, and then dried in an oven at 80ᵒC for 6 hours. Furthermore, the Kenaf fiber and epoxy were mixed manually, while the boards were manufactured using a heat pressing system at 120ᵒC, with a pressure of 3.5 MPa for 10 minutes, and a thickness of 10 mm. The physical and mechanical properties were then evaluated based on JIS A5908. The results showed that the composite board properties were optimum at NaCl 5%, 20% of epoxy, modulus of elasticity and rupture of 2.02 GPa, and 18.63 MPa respectively, internal bonding 1.94 MPa, thickness swelling 2.89 %, and water absorption of 10.49%. The results showed that the physical and mechanical properties of the composite board increased with a high NaCl concentration.

Ionic liquid-plasticised composites of chitosan and hybrid 1D and 2D nanofillers

The focus of this research was to study the effect of combining nanofillers with different geometry and surface chemistry on the structure and properties of biopolymers as an alternative to traditional plastics. How the inclusion of 2D graphene oxide (GO) or reduced GO (rGO) combined with 1D sepiolite (SPT) or cellulose nanocrystals (CNCs) affect the structure and properties of chitosan and chitosan/carboxymethyl cellulose (CMC) materials was investigated. A 3D interconnected microstructure formed, composed of GO and SPT due to the strong interactions between these hydrophilic nanofillers. The chitosan/CMC/GO/SPT composite had the highest tensile strength (77.5 ± 1.2 MPa) and Young’s modulus (1925.9 ± 120.7 MPa). For the un-plasticised matrices, hydrophobic rGO nanosheets generally hindered the interaction of SPT or CNCs with the polysaccharides (chitosan and CMC) and consequently, composite properties were mainly determined by the rGO. However, for the chitosan matrix plasticised by 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), rGO + CNCs or rGO + SPT disrupted polymer chain interactions more effectively than the nanofillers when added alone and resulted in the chitosan being more plasticised, as shown by increased chain mobility, ductility, and surface hydrophilicity. For the [C2mim][OAc]-plasticised chitosan/CMC matrix, the advantages of including hybrid fillers, rGO + CNCs or rGO + SPT, were also obtained, resulting in higher thermal stability and surface hydrophobicity. Graphical Abstract

Study on Thermal, Thermo-Mechanical, and Flexural Properties of Jute Fiber Surface Modification and Its Reinforced Composite

In recent years, reinforced composites from biodegradable and natural fibers have a worldwide scope for advanced applications. However, the core limitation of natural fiber reinforced composites are poor consistency among supporting fibers and the matrix. Therefore, optimal structural performance of fibers and matrix is desirable. In this study, chemical treatments (i.e., alkali pretreatment, acid pretreatment, and scouring) were applied to jute fibers for improvement of composite properties. Thermal, thermo-mechanical, and flexural properties, and surface morphology, of untreated and treated jute fibers were studied on the treated fibers. Jute fiber/epoxy composite properties were analyzed by thermogravimetric analysis (TGA), flexural strength and modulus, and dynamic mechanical analysis (DMA). The chemical treatments had a significant impact on the properties of jute fiber composites.

Effects of Graphite on Electrically Conductive Cementitious Composite Properties: A Review

Electrically conductive cementitious composites (ECCCs) have been widely used to complete functional and smart construction projects. Graphite, due to its low cost and wide availability, is a promising electrically conductive filler to generate electrically conductive networks in cement matrixes. Cement-based materials provide an ideal balance of safety, environmental protection, strength, durability, and economy. Today, graphite is commonly applied in traditional cementitious materials. This paper reviews previous studies regarding the effects and correlations of the use of graphite-based materials as conductive fillers on the properties of traditional cementitious materials. The dispersion, workability, cement hydration, mechanical strength, durability, and electrically conductive mechanisms of cementitious composites modified with graphite are summarized. Graphite composite modification methods and testing methods for the electrical conductivity of ECCCs are also summarized.

Incorporation of Biochar to Improve Mechanical, Thermal and Electrical Properties of Polymer Composites

The strive for utilization of green fillers in polymer composite has increased focus on application of natural biomass-based fillers. Biochar has garnered a lot of attention as a filler material and has the potential to replace conventionally used inorganic mineral fillers. Biochar is a carbon rich product obtained from thermochemical conversion of biomass in nitrogen environment. In this review, current studies dealing with incorporation of biochar in polymer matrices as a reinforcement and conductive filler were addressed. Each study mentioned here is nuanced, while addressing the same goal of utilization of biochar as a filler. In this review paper, an in-depth analysis of biochar and its structure is presented. The paper explored the various methods employed in fabrication of the biocomposites. A thorough review on the effect of addition of biochar on the overall composite properties showed immense promise in improving the overall composite properties. An analysis of the possible knowledge gaps was also done, and improvements were suggested. Through this study we tried to present the status of application of biochar as a filler material and its potential future applications.