High pressure laminates reinforced with electrospun cellulose acetate nanofibers

Recent advances in cellulose-based antimicrobial films: A review

Cellulose, known as the most abundant natural polymer, has renewability, good film-forming, biodegradability, safety, non-toxicity, etc. It can serve as an excellent carrier or substrate for antibacterial agents. In recent years, cellulose antibacterial membranes have become a research hotspot of new antibacterial materials. Cellulose-based antimicrobial films are extensively applied because of their impressive biocompatibility, antimicrobial performance, and other advantages. They are expected to be an effective alternative to petroleum-based antibacterial films. Therefore, the review focuses on the recent progress in cellulose-based antimicrobial films. First, the most widely used antimicrobial agents are described, along with their antibacterial mechanisms. Secondly, the latest research progress on cellulose-based antimicrobial membranes is summarized from the perspective of cellulose-based materials. The fabrication methods of cellulose-based antimicrobial films are then concluded. Finally, the recent advances in the application of cellulose-based antimicrobial film in food packaging, biomedicine, and water treatment are outlined. Moreover, the prospects are made for the study of cellulose-based antimicrobial films.

Preparation and insecticidal performance of 1,8-cineole/cellulose acetate electrospun fibrous membranes

Plant essential oils and their components have broad application prospects as substitutes for chemical pesticides. However, the burst release and persistence time need to be optimized. In this study, 1,8-cineole (1,8-CIN) was embedded in degradable cellulose acetate (CA) by electrospinning to achieve sustained release. The results showed that the sustained-release membrane had good morphology and thermal stability. The release test showed that the deficiency of the explosive release of 1,8-CIN improved after encapsulation, and 21.74 % of the drug remained after 42 days. In the application test, the fiber membrane could kill the test insects in a short period of time and affect the behavior choices of the test insects. It affected the growth and oviposition of the test insects and reduced adult longevity by 13.64 % and oviposition by 23.35 %. This study can improve the utilization rate of pesticides, alleviate environmental pressure, and provide new ideas for pest control.

H2O2 Solution Steaming Combined Method to Cellulose Skeleton for Transparent Wood Infiltrated with Cellulose Acetate

Hydrogen peroxide (H2O2) steaming, a green and highly efficient delignification method, has been demonstrated to provide a wood skeleton with a very low content of residual lignin in the manufacturing of transparent wood. It usually requires a long reaction time and a large amount of H2O2 because the piece of wood is treated using steaming equipment. Herein, a H2O2 solution steaming method was developed for the highly efficient removal of lignin from wood. Specifically, several wood samples were simultaneously immersed in a hot H2O2 solution to obtain delignified wood with a relatively high content of residual lignin, which provided a high strength and preserved the cellulose skeleton. Subsequently, the delignified wood with a relatively high content of residual lignin was further treated with H2O2 steam to obtain a very low lignin delignified wood. Compared with the previous H2O2 steaming method, the reaction time and used H2O2 volume of the H2O2 solution steaming method was reduced by 37.3% and 52.7%, respectively. All-biomass transparent wood could be obtained by infiltrating the delignified wood with cellulose acetate, which showed both a high transmittance of 83.0% and a low thermal conductivity of 0.30 Wm−1K−1.

Co-Loading of Inorganic Nanoparticles and Natural Oil in the Electrospun Janus Nanofibers for a Synergetic Antibacterial Effect

Side-by-side electrospinning is a powerful but challenging technology that can be used to prepare Janus nanofibers for various applications. In this work, cellulose acetate (CA) and polycaprolactone (PCL) were used as polymer carriers for silver nanoparticles (Ag NPs) and lavender oil (LO), respectively, processing these into two-compartment Janus fibers. A bespoke spinneret was used to facilitate the process and prevent the separation of the working fluids. The process of side-by-side electrospinning was recorded with a digital camera, and the morphology and internal structure of the products were characterized by electron microscopy. Clear two-compartment fibers are seen. X-ray diffraction patterns demonstrate silver nanoparticles have been successfully loaded on the CA side, and infrared spectroscopy indicates LO is dispersed on the PCL side. Wetting ability and antibacterial properties of the fibers suggested that PCL-LO//CA-Ag NPs formulation had strong antibacterial activity, performing better than fibers containing only one active component. The PCL-LO//CA-Ag NPs had a 20.08 ± 0.63 mm inhibition zone for E. coli and 19.75 ± 0.96 mm for S. aureus. All the fibers had water contact angels all around 120°, and hence, have suitable hydrophobicity to prevent water ingress into a wound site. Overall, the materials prepared in this work have considerable promise for wound healing applications.

Electrospun nanofiber based on Ethyl cellulose/Soy protein isolated integrated with bitter orange peel extract for antimicrobial and antioxidant active food packaging

The present work was aimed to produce a novel bioactive nanofiber (NFs) based on Ethyl cellulose (EC), Soy protein isolated (SPI), and containing Bitter orange peel extract (BOPE) by electrospinning technology. The EC/SPI NFs were formulated with different weight ratios of 1:1, 2:1, and 1:2 denoted as ES11, ES21, and ES12, respectively, and investigated by several analyses. Based on the obtained results, the maximum hydrogen interactions between these two polymers, ES11 NFs offered a uniform morphology without bead with the diameter of 185.33 nm as a result of the compatibility of the polymer solutions of EC and SPI. Moreover, appropriate thermal stability was presented along with more porosity (78%), maximum water vapor transmission rate (657 g/m2.24h), good tensile stress (6.12 MPa), and acceptable water contact angel (82.3°). Therefore, ES11 NFs were selected as the optimal sample for incorporation of the BOPE as the antibacterial and antioxidant agent. According to the antioxidant activity test, the highest concentration (20% wt) of this extract increased the antioxidant activity of NF around 64.7% and also inhibited the growth of pathogenic bacteria (S. areus, and E. coli). Therefore, the ES11 electrospun NFs containing 20% BOPE can be a beneficial system to increase the safety and quality of foods.