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Eco-friendly, nontoxic and high-energy storage materials are very important for flexible electrode materials. Bi₄Ti₃${\text{O}}_{12}$ lead-free, perovskite phase may prove suitable as filler in composites for electrode materials because of its large spontaneous polarization. We have synthesized Bi₄Ti₃${\text{O}}_{12}$/polystyrene (BTO/PS) composites and carried out their structural, morphological and bonding studies with the help of X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), in that order. Dielectric measurements in the broad frequency range of synthesized composites determined by Impedance analyzer. We observed that the dielectric constant of composites increased with filler concentration and decreased with applied field frequency. Bi₄Ti₃${\text{O}}_{12}$/PS composites can be good electrode materials.

In actual production processes, pure ethyl vinyl acetate (EVA) foams have a high shrinkage rate, and the foaming matrix is prone to plastic deformation, even causing the collapse of bubbles. This limits the further application of EVA foams. In this study, we incorporated styrene butadiene rubber (SBR) and butadiene rubber (BR) into EVA to improve the mechanical properties and dimensional stability of EVA composite foams without sacrificing their low-density characteristics of low density. We used a melting index meter, rotorless vulcanizing meter and dynamic mechanical analysis (DMA) to characterize the changes in viscosity and energy storage modulus of the composite matrix. Scanning electron microscopy (SEM) was used to study the microscopic morphology of foams. The mechanical properties test results showed that the addition of SBR reduced the density of EVA/SBR/BR composite foams, and the addition of BR improved the mechanical properties and dimensional stability of the foams. By combining the advantages of both, the density of products is comparable to pure EVA, the tensile strength and the compressive strength are increased by 11% and 6.3% relative to pure EVA, respectively.

The length of the optical fiber which contains the sensor must be able to withstand the tensile loads that will be placed on it during the duration of its service lifetime. It is important to assess the effect of the UV radiation and removal of coating on the strength of the fiber within the region where the grating has been written. In this study, we have identified the various mechanical and laser fabrication parameters which constrain the strength of fiber gratings. These factors include the laser pulse rate, laser energy per pulse, UV exposure time, methods of coating removal and environmental degradation (moisture). The variation in strength with respect to these factors is discussed in detail. However, it is observed in all the investigations that the average strength of all the fiber grating samples decreased. Finally, the enhancement of mechanical strength of fiber gratings can be achieved by adjusting the laser settings and improving the coating removal methods.

This article studies about the mechanical strength of different functionalized Carbon nanotubes (CNTs) reinforced Polyethylene (PE) fiber composite fabricated by melt spinning. There are four types of CNTs used, which are called as produced, carboxylated, octadecylated, polymer wrapped CNTs. Influence of mechanical drawing (melt spinning) on the mechanical strength of fibers is measured by direct comparison with mechanical strength of bulk type functionalized CNTs polymer composites, which fabricated using hot press. Dispersion and interfacial bonding strength/adhesion of CNTs with PE matrix are investigated through fracture surfaces image analysis. Functionalized CNTs composites show a significant improvement of mechanical strength of pure polymer than non functionalized CNTs polymer composite. Whereas polymer wrapped CNTs polymer composite give the highest mechanical strength in this study. Mechanical strength of bulk composites are significantly increased after mechanical drawing process indicates that melts spinning may influence on the crystallization of polymer. Fracture surface analysis revealed that additional functionalized CNTs enhanced dispersion and interfacial bonding with polymer matrix.

The degree of polymerization (DP) has been regarded as an important symbol of mechanical strength, reflecting the aging condition of transformer insulation paper. In this article, a new concept called fracture degree is proposed on the basis of DP. First, nine cellulose I_β crystal models with different fracture degrees were built. Then relevant mechanical parameters and hydrogen bond numbers were calculated by molecular dynamics (MD) simulation. Results showed that during the aging process of insulation paper with fracture of cellulose chain, the elastic constant C₃₃ produces appreciable impact on the Young's modulus (E). With the decrease of DP and increase of fracture degree, the Young's modulus step decreases. To the 50% and 100% fracture degree models respectively, the relationship between their different degrees of polymerization and Young's modulus is subjected to similar exponential distributions. With the increase of the fracture degree, the average hydrogen bond number drops, and the change rules apply to the Young's modulus. Since hydrogen bond is the main factor of mechanical strength, it can be inferred that the fracture degree influences mechanical strength seriously.

Since the discovery of lasers, high-quality nonlinear optical (NLO) single crystals have served as the foundation for the creation of novel, cutting-edge devices that meet societal demands. Modern optoelectronic applications such as telecommunication lasers, optical fibers, photodiodes, solar cells, etc. favor high-performance nonlinear optical single crystals with improved optical nonlinearity. Organic crystals are extensively explored for these applications because of their high NLO coefficient. This paper deals with the problems and advancements of organic nonlinear optical single crystals. Here, we review the growth and characterizations of various tosylate family crystals from the vast realm of organic single crystals and their potential applications in the field of optoelectronic devices. Various properties like linear and nonlinear optical, thermal, mechanical, and laser damage threshold values for these samples have been summarized. The attempts are made for highlighting how these tosylate (p-Toluenesulfonic acid based) family crystals can be realized into efficient optoelectronic devices by summarizing variously reported cut-off wavelengths and their wide transmission ranges.

A series of acrylic-based superabsorbent resins were synthesized by inverse suspension polymerization, using potassium persulfate as the initiator, N, N′-methylene bisacrylamide (BIS) and divinylbenzene (DVB) as the multiple crosslinking agents. The morphology of the resulting superabsorbent resins revealed by SEM demonstrated that a hard shell layer was indeed formed due to surface crosslinking. The swelling and deswelling properties, and the mechanical strength of superabsorbents were investigated. The results indicated that the adding time of DVB and the amount of DVB participated in the crosslinking show a significant influence on the properties of superabsorbents. When DVB was added in polymerization later, the amount of DVB participated in reaction decreases and the surface crosslinked shell becomes thinner. It is suitable for DVB to be introduced in the later stage of the polymerization process, because the absorption rate of resin is efficiently improved in conjunction with higher water absorption. Furthermore, it was found that the mechanical strength of swollen superabsorbent with surface crosslinking was indeed enhanced in comparison with that of the conventional one.

The compaction of particulate materials to form tablets is increasingly employed as a final dosage form for functional products due to its simplicity and low cost. However, the functionality of some products may be impaired due to the high compression pressures required. The general aim of the current study is to understand the relationship between the mechanical properties of single feed particles (< 100 µm) and their compaction behaviour in order to produce tablets at low compression pressure with acceptable strength. The materials studied were pharmaceutical excipients, comprising three enteric polymer particles and three different powders in the form of agglomerates. The mechanical properties of the individual particles or agglomerates were determined by a micromanipulation technique. The samples were also compacted in cylindrical tableting dies. It was observed that there was a strong correlation between the forces required to cause the fracture of the single particles and those derived from the compaction measurements as determined using an existing analysis.

In this study the response surface methodology (RSM) coupled with the central composite design (CCD) were used to optimize the mechanical strength properties of poly(L-lactide)/multi-walled carbon nanotube (MWCNT) scaffolds. The scaffolds were prepared by the freeze-extraction method. MWCNTs were incorporated into PLLA composite as a reinforcement agent in order to improve the strength properties of the scaffolds. The effect of process parameters such as ratio of PLLA/(PLLA + MWCNT) (93–100%), solvent amount (100–200 ml), freezing time (5–7 h) and immersing time (2–4 days) were studied using the design of experiment (DOE). Based on CCD, quadratic model was obtained and developed to correlate the process parameters to the strength of the scaffolds. An analysis of variance (ANOVA) was applied to determine the significant factors affecting the experimental design response (strength) of the scaffolds. The predicted values after optimization process were in good agreement with the experimental values. The model was able to accurately predict the response of strength with less than 5% error.

New calcium phosphate cement has been developed. The powder component is a mixture of α-tricalcium phosphate, tetracalcium phosphate and calcium hydrogen phosphate dihydrate, while the liquid is an aqueous solution containing sodium succinate and sodium chondroitin sulfate. An injectable paste or a hand-shapeable dough can be prepared by manually mixing the two components for a minute with proper powder to liquid ratio (P/L=2.0-4.5). The mixture can mostly set within about 6 minutes after mixing at 37°C in humid atmosphere, although the setting time is dependent on the P/L and the environmental temperature during the mixing process. The mixture also sets in the simulated body fluid without severe change in pH and gradually turns into low crystalline carbonated hydroxyapatite that can be slowly substituted by bone in vivo. Compressive strength of the cured material is about 65MPa in 3 days after mixing, and reaches its final strength more than 70MPa in a week. Elastic modulus of the hardened body is about 4.5GPa. This is slightly higher than porous hydroxyapatite implants. These strength and biocompatibility as well as less invasive surgical process by injection of this new cement will bring many opportunities to be applied at fracture fixation, filling bone defect and intensification of bone.