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This study investigates the effects of the number of layers, x-yarn (weft) density, and z-yarn (binder) path on the mechanical behavior of E-glass 3D orthogonal woven (3DOW) composites during low-velocity impacts. Meso-level finite element (FE) models were developed and validated for 3DOW composites with different yarn densities and z-yarn paths, providing analyses of stress distribution within reinforcement fibers and matrix, energy absorption, and failure time. Our findings revealed that lower x-yarn densities led to accumulations of stress concentrations. Furthermore, changing the z-yarn path, such as transitioning from plain weaves to twill or basket weaves had a noticeable impact on stress distributions. The research highlights the significance of designing more resilient 3DOW composites for impact applications by choosing appropriate parameters in weaving composite designs.

In the first half of the twentieth century, scientific communities worldwide endeavored to diminish dependence on expensive and scarce animal fibers like wool and silk. Their efforts focused on developing regenerated protein fibers, including soy, zein, and casein, to provide comparable benefits to natural protein fibers, such as lustrous appearance, warmth, and a soft feel. The popularity and cost-effectiveness of mass-produced petroleum-based synthetic polymer fibers during World War II diminished interest in developing soy protein fiber. Realizing the ecological degradation caused by fossil fuels and their derived products, a renewed drive exists to explore bio-based waste materials like soy protein. As a fast-growing crop, soy provides abundant byproducts with opportunities for waste valorization. The soybean oil extraction process produces soy protein as a byproduct, which is a highly tunable biopolymer. Various functional groups within the soy protein structure enable it to acquire different valuable properties. This review critically examines scholarly publications addressing soy protein fiber developmental history, soy protein microstructure modification methods, and soy protein fiber spinning technologies. Additionally, we provide our scientific-based views relevant to overcoming the limitations of previous work and share prospects to make soy protein byproducts viable textile fibers.

Tururi (Manicaria saccifera Gaertn.) is a natural fibrous mesh which protects the fruits of the Amazon Ubuçu palm tree. This research targets developing natural fiber composites from Tururi fibers and characterizing their impact properties. A set of composites from Tururi fiber with different construction parameters (number of layers, fiber orientation, and fiber volume fraction) were manufactured. The results indicated that increasing the number of layers significantly increased the impact resistance up to a limit after which the resin penetration is impaired; moreover, stretching the preform significantly reduced the fiber volume fraction, and hence the impact properties. Finally, the fiber orientation had a negligible effect on the impact energy; yet, it had a significant effect on the failure mechanism.

Fiber-reinforced 3D printing (3DP) technology is a recent addition to the material extrusion-based 3DP process unlocking huge potential to apply this technology for high-performance material fabrication with complex geometries. However, in order to take the full advantage of this technology, a comparative analysis with existing technologies targeting a particular application is necessary to understand its commercial applicability. Here, an applied composite part, ring-spinning travelers, has been developed using the unique design features of fiber-reinforced 3DP technology that is beyond the capability of the currently used technology; the injection molding, quality, and performance of the printed and molded travelers were investigated and compared. The results demonstrated that fiber-reinforced 3DP is a promising technology that offers a lot of flexibility regarding reinforcement patterns and materials including both short and continuous fibers to tailor the performance, although the printed travelers showed poorer surface characteristics and wear resistance than the molded travelers. Based on the present analysis, a number of recommendations have been proposed on the design of the traveler to apply the technology effectively and use the printer to improvise and manipulate the performance of the travelers.

Cellulose microfibrils (CMFs) and micronized rubber powder (MRP) can be derived from low or negative-cost agricultural/industrial waste streams and offer environment-friendly and cost-effective pathways to develop engineering products. This study investigated the efficacy of adding these micromodifiers on the performance characteristics of asphalt binders. In this work, samples were produced using a mixture of slow-setting anionic asphalt emulsion with various combinations of MRP (at 0, 2 and 10 wt %) and four types of CMFs (hydrophobic and hydrophilic with crystalline ratios of 86% and 95%) at 0, 2 and 5 wt %. The performance of modified asphalt samples was assessed by penetration depth (PD), softening point (SP), and penetration index (PI). Linear regression analysis showed that adding CMFs and/or MRP reduced PD and increased SP values. The type of CMFs significantly affected the performance, which becomes more distinct with the increased weight content of CMFs. While hydrophilic CMFs caused increases in SP and PI values, no clear trend was seen to determine the effect of CMF crystallinity. It was also discovered that the combined addition of CMF and MRP achieved similar PI values at lower total weight content compared to using MRP alone.

Three-dimensional printing (3DP) is at the forefront of the disruptive innovations adding a new dimension in the material fabrication process with numerous design flexibilities. Especially, the ability to reinforce the plastic matrix with nanofiber, microfiber, chopped fiber and continuous fiber has put the technology beyond imagination in terms of multidimensional applications. In this technical paper, fiber and polymer filaments used by the commercial 3D printers to develop fiber-reinforced composites are characterized to discover the unknown manufacturing specifications such as fiber–polymer distribution and fiber volume fraction that have direct practical implications in determining and tuning composites’ properties and their applications. Additionally, the capabilities and limitations of 3D printing software to process materials and control print parameters in relation to print quality, structural integrity and properties of printed composites are discussed. The work in this paper aims to present constructive evaluation and criticism of the current technology along with its pros and cons in order to guide prospective users and 3D printing equipment manufacturers on improvements, as well as identify the potential avenues of development of the next generation 3D printed fiber-reinforced composites.

This paper critically reviews previous work in the field of electrospinning of biopolymers and antimicrobial polymeric materials, and investigates the potential of Soy Protein fibers in electrospinning. Biomaterials have since long been the popular choice for fabricating medical textiles or scaffolding materials owing to their biocompatibility, intrinsic anti-microbial activity and low immunogenicity. Even among biopolymers, plant-based protein fibers are more preferred than carbohydrates. Electrospinning of such biopolymers into nanofibers provides one with advantages of properties such as relatively very high porosity, pore interconnectivity, drug-carrying capacity and close similarity to the extra-cellular matrix in the body. Soy protein fibers are envisioned to be an excellent component in fiber spinning mixtures. Mixing of Soy protein with other spinnable polymers such as cellulose, PEO, PVA and chitosan is proposed. Wound-healing is an important application for these materials. The emphasis needs to be on the functionality of such materials, more than mechanical strength which is not a vital necessity for class II medical devices such as wound dressings. A comparatively uninvestigated area is the potential of soy protein fibers for such uses. [ABSTRACT FROM AUTHOR]

This study demonstrates that standard polymer optical fibers (POF) can be directly integrated into composites from 3D orthogonal woven preforms during the weaving process and then serve as in-situ sensors to detect damage due to bending or impact loads. Different composite samples with embedded POF were fabricated of 3D orthogonal woven composites with different parameters namely number of y-/x-layers and x-yarn density. The signal of POF was not affected significantly by the preform structure. During application of resin using VARTM technique, significant drop in backscattering level was observed due to pressure caused by vacuum on the embedded POF. Measurements of POF signal while in the final composites after resin cure indicated that the backscattering level almost returned to the original level of un-embedded POF. The POF responded to application of bending and impact loads to the composite with a reduction in the backscattering level. The backscattering level almost returned back to its original level after removing the bending load until damage was present in the composite. Similar behavior occurred due to impact events. As the POF itself is used as the sensor and can be integrated throughout the composite, large sections of future 3D woven composite structures could be monitored without the need for specialized sensors or complex instrumentation. [ABSTRACT FROM AUTHOR]