Effect of Mixing Time on Properties of Whole Wheat Flour-Based Cookie Doughs and Cookies.

This study investigated if whole wheat flour-based cookie dough's physical properties were affected by mixing time (1 to 10 min). The cookie dough quality was assessed using texture (spreadability and stress relaxation), moisture content, and impedance analysis. The distributed components were better organized in dough mixed for 3 min when compared with the other times. The segmentation analysis of the dough micrographs suggested that higher mixing time resulted in the formation of water agglomeration. The infrared spectrum of the samples was analyzed based on the water populations, amide I region, and starch crystallinity. The analysis of the amide I region (1700-1600 cm-1) suggested that ß-turns and ß-sheets were the dominating protein secondary structures in the dough matrix. Conversely, most samples' secondary structures (α-helices and random coil) were negligible or absent. MT3 dough exhibited the lowest impedance in the impedance tests. Test baking of the cookies from doughs mixed at different times was performed. There was no discernible change in appearance due to the change in the mixing time. Surface cracking was noticeable on all cookies, a trait often associated with cookies made with wheat flour that contributed to the impression of an uneven surface. There was not much variation in cookie size attributes. Cookies ranged in moisture content from 11 to 13.5%. MT5 (mixing time of 5 min) cookies demonstrated the strongest hydrogen bonding. Overall, it was observed that the cookies hardened as mixing time rose. The texture attributes of the MT5 cookies were more reproducible than the other cookie samples. In summary, it can be concluded that the whole wheat flour cookies prepared with a creaming time and mixing time of 5 min each resulted in good quality cookies. Therefore, this study evaluated the effect of mixing time on the physical and structural properties of the dough and, eventually, its impact on the baked product.

Effect of Accelerated Weathering on the Thermal, Tensile, and Morphological Characteristics of Polypropylene/Date Nanofiller Composites.

The aging of polypropylene (PP) composites reinforced with date palm nanofiber (DNF) was investigated in this study in order to predict their long-term performance. To produce composites, date palm nanofibers in the range of 1-5 wt% loading were dry-melt-blended with polypropylene. These biocomposites were then subjected to UV exposure (Xenon arch source) for accelerated weathering for 250 and 500 h according to a standard method. The change in thermal properties before and after accelerated weathering was investigated using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). TGA analysis shows that the maximum degradation temperature for sample at 1 wt% loading was 382.7 °C, which slightly decreased to 379.9 °C after 250 h and to 367.7 °C after 500 h of weathering. DSC analysis also revealed lower crystallinity of the same samples after exposure to accelerated weathering. Mechanical properties were also studied to identify the damage induced by accelerated weathering. The tensile strength of the highest loading (5 wt%) of the sample was found to occur at 34.83 MPa, which was slightly lowered to 31.64 after 500 h treatment. A minimal decrease in tensile strength, deterioration, and weathering-induced oxidation indicates the excellent stability of these composites. Therefore, our study provides insight into the aging behavior of such composites, which may be useful in dry conditions, as well as nonstructural automotive and other parts for which minimum tensile strength (~25 MPa) is specified.

Development of a Soft Robotic Bending Actuator Based on a Novel Sulfonated Polyvinyl Chloride-Phosphotungstic Acid Ionic Polymer-Metal Composite (IPMC) Membrane.

This work presents the development of a cost-effective electric-stimulus-responsive bending actuator based on a sulfonated polyvinyl chloride (SPVC)-phosphotungstic acid (PTA) ionic polymer-metal composite (IPMC), using a simple solution-casting method followed by chemical reduction of platinum (Pt) ions as an electrode. The characterizations of the prepared IPMC were performed using Fourier-transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques, Thermogravimetric analysis (TGA), and Energy-dispersive X-ray (EDX) analysis. Excellent ion-exchange capacity (IEC) and proton conductivity (PC), with values of ca. 1.98 meq·g-1 and ca. 1.6 mS·cm-1, respectively, were observed. The water uptake (WU) and water loss (WL) capacities of the IPMC membranes were measured at 25 °C, and found to have maxima of ca. 48% for 10 h, and ca. 36% at 6 V DC for almost 9 min, respectively. To analyze the actuation performance of the developed membrane, tip displacement and actuation force measurements were conducted. Tip displacement was found to be ca. 15.1 mm, whereas bending actuation was found to be 0.242 mN at 4 V DC. The moderate water loss, good proton conductivity (PC), high thermal stability, and good electrochemical properties of the developed IPMC membrane actuator position it as a cost-effective alternative to highly expensive conventional perfluorinated polymer-based actuators.

Development of Bigels Based on Date Palm-Derived Cellulose Nanocrystal-Reinforced Guar Gum Hydrogel and Sesame Oil/Candelilla Wax Oleogel as Delivery Vehicles for Moxifloxacin.

Bigels are biphasic semisolid systems that have been explored as delivery vehicles in the food and pharmaceutical industries. These formulations are highly stable and have a longer shelf-life than emulsions. Similarly, cellulose-based hydrogels are considered to be ideal for these formulations due to their biocompatibility and flexibility to mold into various shapes. Accordingly, in the present study, the properties of an optimized guar gum hydrogel and sesame oil/candelilla wax oleogel-based bigel were tailored using date palm-derived cellulose nanocrystals (dp-CNC). These bigels were then explored as carriers for the bioactive molecule moxifloxacin hydrochloride (MH). The preparation of the bigels was achieved by mixing guar gum hydrogel and sesame oil/candelilla wax oleogel. Polarizing microscopy suggested the formation of the hydrogel-in-oleogel type of bigels. An alteration in the dp-CNC content affected the size distribution of the hydrogel phase within the oleogel phase. The colorimetry studies revealed the yellowish-white color of the samples. There were no significant changes in the FTIR functional group positions even after the addition of dp-CNC. In general, the incorporation of dp-CNC resulted in a decrease in the impedance values, except BG3 that had 15 mg dp-CNC in 20 g bigel. The BG3 formulation showed the highest firmness and fluidity. The release of MH from the bigels was quasi-Fickian diffusion mediated. BG3 showed the highest release of the drug. In summary, dp-CNC can be used as a novel reinforcing agent for bigels.

Date-Palm-Derived Cellulose Nanocrystals as Reinforcing Agents for Poly(vinyl alcohol)/Guar-Gum-Based Phase-Separated Composite Films.

The current study delineates the use of date-palm-derived cellulose nanocrystals (dp-CNCs) as reinforcing agents. dp-CNCs were incorporated in varying amounts to poly(vinyl alcohol)/guar-gum-based phase-separated composite films. The films were prepared by using the solution casting method, which employed glutaraldehyde as the crosslinking agent. Subsequently, the films were characterized by bright field and polarizing microscopy, UV-Vis spectroscopy, FTIR spectroscopy, and mechanical study. The microscopic techniques suggested that phase-separated films were formed, whose microstructure could be tailored by incorporating dp-CNCs. At higher levels of dp-CNC content, microcracks could be observed in the films. The transparency of the phase-separated films was not significantly altered when the dp-CNC content was on the lower side. FTIR spectroscopy suggested the presence of hydrogen bonding within the phase-separated films. dp-CNCs showed reinforcing effects at the lowest amount, whereas the mechanical properties of the films were compromised at higher dp-CNC content. Moxifloxacin was included in the films to determine the capability of the films as a drug delivery vehicle. It was found that the release of the drug could be tailored by altering the dp-CNC content within the phase-separated films. In gist, the developed dp-CNC-loaded poly(vinyl alcohol)/guar-gum-based phase-separated composite films could be explored as a drug delivery vehicle.

Synthesis and Characterization of Cellulose Triacetate Obtained from Date Palm (Phoenix dactylifera L.) Trunk Mesh-Derived Cellulose.

Cellulosic polysaccharides have increasingly been recognized as a viable substitute for the depleting petro-based feedstock due to numerous modification options for obtaining a plethora of bio-based materials. In this study, cellulose triacetate was synthesized from pure cellulose obtained from the waste lignocellulosic part of date palm (Phoenix dactylifera L.). To achieve a degree of substitution (DS) of the hydroxyl group of 2.9, a heterogeneous acetylation reaction was carried out with acetic anhydride as an acetyl donor. The obtained cellulose ester was compared with a commercially available derivative and characterized using various analytical methods. This cellulose triacetate contains approximately 43.9% acetyl and has a molecular weight of 205,102 g·mol-1. The maximum thermal decomposition temperature of acetate was found to be 380 °C, similar to that of a reference sample. Thus, the synthesized ester derivate can be suitable for fabricating biodegradable and "all cellulose" biocomposite systems.

A Convenient and Simple Ionic Polymer-Metal Composite (IPMC) Actuator Based on a Platinum-Coated Sulfonated Poly(ether ether ketone)-Polyaniline Composite Membrane.

Herein, we present new approaches for developing sulfonated polyether ether ketone (SPEEK) and polyaniline-based (PANI) actuator formed by film-casting and chemical reduction of Pt electrodes. We have thoroughly studied the synthesis of SPEEK and characterized it by different analytical techniques. The ion-exchange capacity (IEC) and proton conductivity of SPEEK-PANI polymer membrane were calculated to be 1.98 mmol g-1 and 1.97 × 10-3 S cm-1, respectively. To develop an IPMC actuator, SPEEK was combined with PANI through in-situ polymerization method. SEM and XRD were used to check the morphology of the given SPEEK-PANI-Pt membrane. In addition, FT-IR and EDX techniques confirmed the molecular structure and chemical conformation of SPEEK-PANI polymer membrane. Pt electrode layers homogeneously dispersed on the IPMC membrane surface, which was demonstrated by smooth SEM micrographs. The actuation functioning, including the high bending deflection, proton conductivity, current density and IEC of IPMC actuator based on SPEEK-PANI-Pt, was obtained owing to its strong electrochemical and electromechanical characteristics. Synergistic combinations of SPEEK and PANI produced membrane that are flexible, mechanically strong and robust. The developed materials have immense capability as actuators for various applications including in biomimetics and robotics.

Isolation and Characterization of Alpha and Nanocrystalline Cellulose from Date Palm (Phoenix dactylifera L.) Trunk Mesh.

Highly pure cellulosic polymers obtained from waste lignocellulose offer great potential for designing novel materials in the concept of biorefinery. In this work, alpha-cellulose and nanocrystalline cellulose were isolated from the date palm trunk mesh (DPTM) through a series of physicochemical treatments. Supercritical carbon dioxide treatment was used to remove soluble extractives, and concentrated alkali pretreatment was used to eliminate the lignin portion selectively to obtain alpha-cellulose in approximately 94% yield. Further treatments of this cellulose yielded nanocrystalline cellulose. The structure-property relationship studies were carried out by characterizing the obtained polymers by various standard methods and analytical techniques such as Fourier transform infrared spectroscopy-attenuated total reflection (FTIR-ATR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), energy dispersive X-ray diffraction (EDX-XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Almost 65% yield of pure cellulose was achieved, out of which 94% is the alpha-cellulose. This cellulose shows good thermal stability and crystallinity. The microscopic analysis of the nanocellulose showed a heterogeneous mix of irregular-shaped particles with a size range of 20-60 nm. The percentage crystallinity of alpha-cellulose and nanocellulose was found to be 68.9 and 71.8, respectively. Thus, this study shows that, this DPTM-based low-cost waste biomass can be a potential source to obtain cellulose and nano-cellulose.

Engineered biochar from wood apple shell waste for high-efficient removal of toxic phenolic compounds in wastewater.

This study investigated a novel agricultural low-cost bio-waste biochar derived from wood apple fruit shell waste via the pyrolysis method, which is modified by ball milling and utilized to remove toxic phenol and chlorophenols (4-CPh and 2,4-DCPh) from contaminated aqueous media. The ball-milled wood apple fruit shell waste biochar (WAS-BC) sorbent was systematically analyzed by BET, CHN, and FTIR as well as particle size, SEM-EDS, XPS and TGA studies. The sorption equilibrium and kinetic studies exhibit that the sorption capacity was greater than 75% within the first 45 min of agitation at pH 6.0. The uptake capacity of 2,4-DCPh onto WAS-BC was greater than those of 4-CPh and phenol. Equilibrium results were consistent with the Langmuir isotherm model, while the kinetic data were best represented by the Elovich and pseudo-second-order model. The maximum uptake of phenol, 4-CPh, and 2,4-DCPh was 102.71, 172.24, and 226.55 mg/g, respectively, at 30 ± 1 °C. Thus, this study demonstrates that WAS-BC is an efficient, low-cost sorbent that can be used for the elimination of phenol and chlorophenol compounds from polluted wastewater.