scholarly journals Characterization and Filtration Efficiency of Sustainable PLA Fibers Obtained via a Hybrid 3D-Printed/Electrospinning Technique

Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6766
Author(s):  
Mattia Pierpaoli ◽  
Chiara Giosuè ◽  
Natalia Czerwińska ◽  
Michał Rycewicz ◽  
Aleksandra Wieloszyńska ◽  
...  
Keyword(s):  
Corn Starch ◽  
Face Mask ◽  
Equivalent Diameter ◽  
Air Filtration ◽  
Electrospinning Technique ◽  
Aerosol Filtration ◽  
World Demand ◽  
3D Printed ◽  
Single Use ◽  
Reproducible Method

The enormous world demand for personal protective equipment to face the current SARS-CoV-2 epidemic has revealed two main weaknesses. On one hand, centralized production led to an initial shortage of respirators; on the other hand, the world demand for single-use equipment has had a direct and inevitable effect on the environment. Polylactide (PLA) is a biodegradable, biocompatible, and renewable thermoplastic polyester, mainly derived from corn starch. Electrospinning is an established and reproducible method to obtain nano- and microfibrous materials with a simple apparatus, characterized by high air filtration efficiencies. In the present work, we designed and optimized an open-source electrospinning setup, easily realizable with a 3D printer and using components widely available, for the delocalized production of an efficient and sustainable particulate matter filter. Filters were realized on 3D-printed PLA support, on which PLA fibers were subsequently electrospun. NaCl aerosol filtration tests exhibited an efficiency greater than 95% for aerosol having an equivalent diameter greater than 0.3 μm and a fiber diameter comparable to the commercially available FFP2 melt-blown face mask. The particulate entrapped by the filters when operating in real environments (indoors, outdoors, and working scenario) was also investigated, as well as the amount of heavy metals potentially released into the environment after filtration activity.

scholarly journals Non-woven materials for cloth-based face mask inserts: Relationship between material properties and sub-micron aerosol filtration

2021 ◽  
Author(s):  
Leigh Crilley ◽  
Brian Malile ◽  
Andrea Angelucci ◽  
Cora Young ◽  
Trevor C. VandenBoer ◽  
...  
Keyword(s):  
Public Health ◽  
Material Properties ◽  
Face Mask ◽  
Respiratory Viruses ◽  
Public Health Agencies ◽  
Aerosol Filtration ◽  
Health Agencies ◽  
Current Guidance

Current guidance by leading public health agencies recommends wearing a 3-layer cloth-based face mask with a middle non-woven material insert to reduce the transmission of infectious respiratory viruses like SARS-CoV-2....

scholarly journals Waste generation as a side impact of the COVID-19 pandemic: Communication on correct disposal of single-use face masks

2021 ◽  
Author(s):  
Débora Tomaszewski
Keyword(s):  
Face Mask ◽  
Side Impact ◽  
Waste Generation ◽  
Visual Aids ◽  
Plastic Pollution ◽  
Environmental Consequences ◽  
Global Spread ◽  
Single Use ◽  
Regional Authorities ◽  
Primary Measure

The rapid global spread of SARS-CoV-2 and the resulting Coronavirus disease (COVID-19) pandemic has led to urgent efforts to contain and mitigate transmission. The useof face masks became a primary measure to limit the spread, which increased the production and consequentwaste generation. It is estimated that globally 129 billion single-use face masks are discharged into the environment every month. Besides to add to already great concerns over plastic pollution, contaminated face masks not properly handled also poses a health risk. The health and environmental consequences caused by the inadequate disposal of single-use face masks are treated in this study as an eminent risk to be properly communicated. This study framed the waste generation as a side impact of the COVID-19 pandemic and analysed how the communication has been made regarding the correct disposal of single-use masks, with focus in users of public transport in Stockholm region. National and regional authorities are recognized as the main responsibles for the communication about correct disposal, together with manufacturers and suppliers of single-use face masks. Disclosure and informative material of four government authorities and instruction manuals of eight brands of single-use face masks are analysed according to: i) presence / absence of information (about the disposal); ii) type of communication (visual or written); iii) message transmitted and; ix) availability in other languages.It was found guidance about correct disposal of face mask in two thirds of the existing communication, that is mainly written and with few visual aids. Half of communication is made only in Swedish and with no sufficient focus on the importance of correct disposal neither with reference to trash bins with lid. It suggests that the current communication about how to disposesingle-use masks safelymay not be enough, which is affecting the perception of risk by the population and worsening the health and environmental consequencescaused by the inadequate disposal.

scholarly journals 3D Printing 18F Radioactive Phantoms for PET Imaging

2020 ◽  
Author(s):  
Daniel Gillett ◽  
Daniel Marsden ◽  
Safia Ballout ◽  
Bala Attili ◽  
Nick Bird ◽  
...  
Keyword(s):  
Double Helix ◽  
Human Anatomy ◽  
Radioactive Material ◽  
Ct Scanner ◽  
Pet Ct ◽  
Radioactive Concentration ◽  
3D Printed ◽  
Single Use ◽  
The Mean ◽  
Cylinders And Spheres

Abstract Purpose: Phantoms are routinely used in molecular imaging to assess scanner performance. However, traditional phantoms with fillable shapes do not replicate human anatomy. 3D printed phantoms have overcome this by creating phantoms which replicate human anatomy which can be filled with radioactive material. The problem with these is that small objects suffer from boundary effects and therefore boundary-free objects are desirable. The purpose of this study was to explore the feasibility of creating resin-based 3D printed phantoms using 18 F-FDG. Methods: Radioactive resin was created using an emulsion of printer resin and 18 F-FDG. A series of test objects were printed including twenty identical cylinders, ten spheres with increasing diameters (2 mm to 20 mm) and a double helix. Radioactive concentration uniformity, printing accuracy and the amount of leaching were assessed. Results: Creating radioactive resin was simple and effective. The radioactivity remained bound to the resin for the duration that it was radioactive. The radioactive concentration was uniform among identical objects; the CoV of the mean, max and total signal were 3.6%, 3.8% and 2.6%, respectively. The printed cylinders and spheres were found to be within 4% of the model dimensions. A double helix was successfully printed as a test for the printer and appeared as expected on the PET scanner. The amount of radioactivity leached into the water was measurable (0.72%) but not visible above background on the imaging. Conclusions: Creating an 18F-FDG radioactive resin emulsion is a simple and effective way to create boundary-free, accurate, complex 3D phantoms that can be imaged using a PET/CT scanner. This technique could be used to print clinically realistic phantoms, however, they are single use, and cannot be made hollow without an exit hole. Also, there is a small amount of leaching of the radioactivity to take into consideration.

scholarly journals 3D Printed frames to enable reuse and improve the fit of N95 and KN95 respirators

2020 ◽  
Author(s):  
Malia McAvoy ◽  
Ai-Tram N. Bui ◽  
Christopher Hansen ◽  
Deborah Plana ◽  
Jordan T. Said ◽  
...  
Keyword(s):  
3D Printing ◽  
Design Process ◽  
Clinical Settings ◽  
Short Supply ◽  
Iterative Design ◽  
Healthcare Settings ◽  
Fit Testing ◽  
3D Printed ◽  
Single Use ◽  
Repeated Use

Background: In response to supply shortages during the COVID-19 pandemic, N95 filtering facepiece respirators (FFRs or "masks"), which are typically single-use devices in healthcare settings, are routinely being used for prolonged periods and in some cases decontaminated under "reuse" and "extended use" policies. However, the reusability of N95 masks is often limited by degradation or breakage of elastic head bands and issues with mask fit after repeated use. The purpose of this study was to develop a frame for N95 masks, using readily available materials and 3D printing, which could replace defective or broken bands and improve fit. Results: An iterative design process yielded a mask frame consisting of two 3D-printed side pieces, malleable wire links that users press against their face, and cut lengths of elastic material that go around the head to hold the frame and mask in place. Volunteers (n= 41; average BMI= 25.5), of whom 31 were women, underwent qualitative fit with and without mask frames and one or more of four different brands of FFRs conforming to US N95 or Chinese KN95 standards. Masks passed qualitative fit testing in the absence of a frame at rates varying from 48-92% (depending on mask model and tester). For individuals for whom a mask passed testing, 75-100% (average = 86%) also passed testing with a frame holding the mask in place. Among users for whom a mask failed in initial fit testing, 41% passed using a frame. Success varied with mask model and across individuals. Conclusions: The use of mask frames can prolong the lifespan of N95 and KN95 masks by serving as a substitute for broken or defective bands without adversely affecting fit. Frames also have the potential to improve fit for some individuals who cannot fit existing masks. Frames therefore represent a simple and inexpensive way of extending the life and utility of PPE in short supply. For clinicians and institutions interested in mask frames, designs and specifications are provided without restriction for use or modification. To ensure adequate performance in clinical settings, qualitative fit testing with user-specific masks and frames is required.

scholarly journals Robust polyimide nano/microfibre aerogels welded by solvent-vapour for environmental applications

2019 ◽  
Vol 6 (8) ◽  
pp. 190596 ◽  
Author(s):  
Ying Shen ◽  
Dawei Li ◽  
Bingyao Deng ◽  
Qingsheng Liu ◽  
Huizhong Liu ◽  
...  
Keyword(s):  
Compressive Strain ◽  
Building Blocks ◽  
Uniform Structure ◽  
Low Density ◽  
High Porosity ◽  
Air Filtration ◽  
Solvent Vapour ◽  
Fibrous Network ◽  
Aerosol Filtration ◽  
New Perspective

Due to the high porosity, resilience and ultra-low density, polymer nanofibre-derived aerogels (NFAs) have been widely investigated in recent years. However, welding of the fibrous networks of NFAs, which has been proved extremely essential to their structural performance, still remains a major challenge. Herein, electrospun polyimide (PI) nano/microfibres were used as building blocks to construct hierarchically porous aerogels through a solid-templating technique. By further welding the adjacent nano/microfibres at their cross-points in a controllable fashion by solvent-vapour, super elasticity was achieved for the aerogels, with a recoverable ultimate strain of 80%. It is noteworthy that this process is free from cross-linking, heating and significant structure changing (i.e. chemical structure, crystallinity and fibrous network). Additionally, the porous structure of PI nano/microfibre aerogels (PI-N/MFAs) could be tuned by adjusting the organization of microfibres from a disordered/ordered cellular to a uniform structure. The as-obtained aerogels showed ultra-low density (4.81 mg cm −3 ), high porosity (99.66%), and comparable or higher recoverable compressive strain and stress relative to the other nanofibre-based aerogels. Furthermore, we showed the potential of such an aerogel for particle or aerosol filtration. PI nanofibre aerogels composite filters (PI-NFACFs) manifested excellent performance in PM 2.0 filtration (99.6% filtration efficiency with 115 Pa pressure drop). Therefore, this study brought a new perspective on the simple preparation of nanofibre-based aerogels for air filtration.

scholarly journals 3D Printing to Support the Shortage in Personal Protective Equipment Caused by COVID-19 Pandemic

Materials ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3339 ◽  
Author(s):  
Mostapha Tarfaoui ◽  
Mourad Nachtane ◽  
Ibrahim Goda ◽  
Yumna Qureshi ◽  
Hamza Benyahia
Keyword(s):  
3D Printing ◽  
Medical Devices ◽  
Personal Protective Equipment ◽  
Health Concern ◽  
Protective Equipment ◽  
Global Public Health ◽  
Comprehensive Overview ◽  
3D Printed ◽  
Single Use ◽  
Tract Infections

Currently, the emergence of a novel human coronavirus disease, named COVID-19, has become a great global public health concern causing severe respiratory tract infections in humans. Yet, there is no specific vaccine or treatment for this COVID-19 where anti-disease measures rely on preventing or slowing the transmission of infection from one person to another. In particularly, there is a growing effort to prevent or reduce transmission to frontline healthcare professionals. However, it is becoming an increasingly international concern respecting the shortage in the supply chain of critical single-use personal protective equipment (PPE). To that scope, we aim in the present work to provide a comprehensive overview of the latest 3D printing efforts against COVID-19, including professional additive manufacturing (AM) providers, makers and designers in the 3D printing community. Through this review paper, the response to several questions and inquiries regarding the following issues are addressed: technical factors connected with AM processes; recommendations for testing and characterizing medical devices that additively manufactured; AM materials that can be used for medical devices; biological concerns of final 3D printed medical parts, comprising biocompatibility, cleaning and sterility; and limitations of AM technology.

scholarly journals The Adsorption Mechanism of Activated Carbon and Its Application - A Review

2021 ◽  
Vol 1 (3) ◽  
pp. 118-124
Author(s):  
Muhammad S. Muzarpar ◽  
A. M. Leman
Keyword(s):  
Activated Carbon ◽  
Adsorption Mechanism ◽  
Daily Life ◽  
Chemical Activation ◽  
Face Mask ◽  
Water Filtration ◽  
Physical Activation ◽  
Activation Process ◽  
Air Filtration ◽  
Production Face

Activated carbon (AC) was recognized by many researchers as useful substance in adsorption of impurities. Several processes involved in the production of AC which were carbonization, crushing, and activation process. Carbonization of carbon required high temperature up to 900oC. Then the carbon will be crush to a desired size for activation process. Activation of carbon can be either chemical activation, physical activation or combination of chemical and physical activation which called physiochemical activation. The mechanism adsorption of AC commonly due to its micropore present in the carbon or the weak vander waals forces which can attract the impurities. Activated carbon have multiple function in human daily life. This study will be discuss the function of AC in the production face mask, water filtration and air filtration.

scholarly journals Non-Woven Materials for Cloth-Based Face Mask Inserts: Relationship Between Material Properties and Sub-Micron Aerosol Filtration

2021 ◽  
Author(s):  
Leigh R. Crilley ◽  
Andrea Angelucci ◽  
Brian Malile ◽  
Cora J. Young ◽  
Trevor C. VandenBoer ◽  
...  
Keyword(s):  
Face Mask ◽  
Filtration Efficiency ◽  
Evidence Based ◽  
Public Health Agencies ◽  
Wide Range ◽  
Aerosol Filtration ◽  
Health Agencies ◽  
Micron Particle ◽  
Current Guidance ◽  
Evidence Based Guidelines

<div>Current guidance by leading public health agencies recommends wearing a 3-layer cloth-based face mask with a middle non-woven material insert to reduce the transmission of infectious respiratory viruses like SARS-CoV-2. In this work we explore the material characteristics for a range of readily available non-woven materials and their sub-micron particle filtration efficiency (PFE), with the aim of providing evidence-based guidelines for selecting appropriate materials as inserts in cloth-based masks. We observed a wide range of ideal PFE for the tested non-woven materials, with polypropylene, Swiffer and Rayon/polyester blend providing the highest PFE and breathability. Our results suggest that materials comprising loose 3D fibrous webs (e.g. flannel, Swiffer and gauze) exhibited enhanced filtration efficiency compared to compressed counterparts. Common modifications to fabrics, such as water-resistant treatment and a sewn seam were also investigated. Overall, we demonstrate that adding an appropriate non-woven material as an insert filter can significantly improve the performance of cloth-based masks, and there exist suitable cellulose-based alternatives to polypropylene.</div>

scholarly journals Synthesis of Electrospun Nanofibers Membrane and Its Optimization for Aerosol Filter Application

2016 ◽  
Vol 1 ◽  
Author(s):  
Abdul Rajak
Keyword(s):  
Pressure Drop ◽  
Fiber Diameter ◽  
Polymer Concentration ◽  
Electrospun Nanofibers ◽  
Diameter Distribution ◽  
Air Filtration ◽  
Sem Image ◽  
Aerosol Filtration ◽  
Electrospinning Method ◽  
Fiber Diameter Distribution

Nanofibers membranes were synthesized using electrospinning method for air filtration application. Polyacrylonitrile (PAN) with three different concentrations as the polymeric matrix of the nanofibers membrane is used. In the aerosol filtration, the pressure drop is one of the most important parameters, which is determined by the membrane characteristics. One of the parameters that influence the characteristics of membrane is concentration of polymer solution, in which it will determine the diameter of fiber. In this study, the relation between the PAN concentration and the pressure drop in air filtration test was examined. Three different concentrations of PAN solution (6, 9, and 12 wt.%) were employed under the same process parameters of electrospinning. The fiber diameter distribution of each membrane was measured from its scanning electron microscope (SEM) image. The three concentrations resulted in significant different effect to the pressure drop that proved the existing correlation between the polymer concentration and the air pressure drop.

Sign in / Sign up

Export Citation Format

Share Document