Biodegradation of Polymer Coatings

AbstractConventional paint removal methods include chemical stripping with VOCs, blasting with plastic media, and delamination with high pressure water. These methods have many limitations, in that they are labor intensive, pose human health risks, are relatively expensive and pose significant waste disposal problems. However, polymeric coatings are known to contain structural components, such as ester, amide and urea linkages, that can be degraded biologically. We are working to develop a stable, enzyme-based, non-toxic paint stripping strategy that will be environmentally safe and cost effective.The specific objectives are to identify and characterize microbial systems capable of degrading polymeric coatings, to develop a quantitative degradation assay and to optimize activity levels for subsequent purification and concentration of the biological products required for rapid degradation of coatings.A water-dispersed colloid of an ester-based polyurethane polymer has been used in solid growth medium to screen about 100 different bacteria for microbial degradation activity. Those with demonstrable activity have been grown in the presence of epoxypolyamide paint- and polyester polyurethane paint-coated aluminum coupons. We have demonstrated delamination under certain conditions and have developed a spectrophotometric method for quantitating degradation activity as a function of dye release.

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Physical Properties of Electropolished CoCrMo Alloy Coated with Biodegradable Polymeric Coatings Releasing Heparin after Prolonged Exposure to Artificial Urine

Materials ◽

10.3390/ma14102551 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2551

Author(s):

Wojciech Kajzer ◽

Janusz Szewczenko ◽

Anita Kajzer ◽

Marcin Basiaga ◽

Joanna Jaworska ◽

...

Keyword(s):

Physical Properties ◽

Crevice Corrosion ◽

Mass Density ◽

Polymer Coatings ◽

Metal Substrate ◽

Reference Level ◽

Polymeric Coatings ◽

Initial State ◽

Cocrmo Alloy ◽

Artificial Urine

In this study, we aimed to determine the effect of long-term exposure to artificial urine on the physical properties of CoCrMo alloy with biodegradable heparin-releasing polymeric coatings. Variants of polymer coatings of poly(L,L-lactide-ɛ-caprolactone) (P(L,L-L/CL)) and poly(D,L-lactide-ɛ-caprolactone) (P(D,L-L/CL)) constituting the base for heparin-releasing (HEP) polyvinyl alcohol (PVA) coatings were analyzed. The coatings were applied by the dip-coating method. Heparin was used to counteract the incrustation process in the artificial urine. The study included tests of wettability, resistance to pitting and crevice corrosion, determination of the mass density of metal ions penetrating into the artificial urine, and the kinetics of heparin release. In addition, microscopic observations of surface roughness and adhesion to the metal substrate were performed. Electrolytically polished CoCrMo samples (as a reference level) and samples with polymer coatings were used for the tests. The tests were conducted on samples in the initial state and after 30, 60, and 90 days of exposure to artificial urine. The analysis of the test results shows that the polymer coatings contribute by improving the resistance of the metal substrate to pitting and crevice corrosion in the initial state and reducing (as compared with the metal substrate) the mass density of metal ion release into the artificial urine. Moreover, the PVA + HEP coating, regardless of the base polymer coatings used, contributes to a reduction in the incrustation process in the first 30 days of exposure to the artificial urine.

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A modern-day solution to a 100-yearold problem: the use of a bespoke offloading brace in the rehabilitation of ‘Deck-Slap’ and other high-energy lower limb injuries

Journal of The Royal Naval Medical Service ◽

10.1136/jrnms-100-337 ◽

2014 ◽

Vol 100 (3) ◽

pp. 337-343

Author(s):

MA Osborne ◽

HL Jarvis ◽

N Bennett ◽

RD Phillip

Keyword(s):

Axial Loading ◽

Cost Effective ◽

Armed Forces ◽

High Energy ◽

Lower Limbs ◽

Limb Amputation ◽

Activity Levels ◽

Prosthetic Devices ◽

Functional Benefit ◽

Limb Injuries

Abstract‘Deck-Slap’ is an injury pattern first described at the Battle of Jutland; it is still relevant today, with anti-vehicle mines a significant threat to Coalition troops. The effect of a device exploding beneath a vehicle produces a wave of high energy that is rapidly transmitted through the steel floor; this causes significant axial loading of lower limbs often resulting in severe fractures (notably of the calcaneum). Recent advancements in orthopaedic surgery have allowed for limbs that were destined for immediate amputation following significant trauma to be salvaged. However, despite intense rehabilitation, many of these salvaged limbs have subsequently gone on to delayed amputation, as functional outcomes are often poor. Technologically advanced prosthetic devices are available that afford good quality of life and allow for increased activity levels; these devices are, however, expensive to procure and maintain. This report describes a United Kingdom (UK) Armed Forces soldier who suffered a typical ‘deck-slap’ injury in Afghanistan with subsequent limb salvage. The use of the Bespoke Off-loading Brace (BOB) is discussed. The results presented here indicate that the biomechanical function of a patient with this type of injury improves when wearing the BOB. Further studies are needed to assess long-term clinical outcomes and the functional benefit of the device as a viable and cost-effective alternative to delayed limb amputation.

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The Susceptibility of Healthy People to COVID-19 Infection and the Role of ACE2

Journal of Iranian Medical Council ◽

10.18502/jimc.v4i3.7212 ◽

2021 ◽

Author(s):

Mehdi Kushkestani ◽

Mohsen Parvani ◽

Bakhtyar Tartibian ◽

Rasoul Eslami

Keyword(s):

Risk Factors ◽

Cost Effective ◽

Normal Subjects ◽

Definitive Treatment ◽

Activity Levels ◽

Cost Effective Approach ◽

Increased Risk ◽

Physical Activity Levels ◽

Ace2 Gene

The COVID-19 virus has caused many deaths of people worldwide since the pandemic began. However, no definitive treatment for this infection has been discovered so far. It has been shown that comorbidities such as diabetes, hypertension and cardiovascular diseases are associated with an increased risk of SARS-COV-2 infection. Interestingly, SARS-COV-2, like SARS-COV, uses the ACE2 gene to enter the host cell. Also, changes or imbalance in ACE2.ACE can affect SARS-COV-2 susceptibility, related outcomes and mortality. Regarding the crucial role of ACE2 protein in COVID-19 infection, the effect of different factors such as age, BMI, physical activity levels, nutritional status, altitude, as well as blood group was assessed on the level of this protein. Further, to our knowledge, no study has been conducted to examine factors that increase or decrease the risk of COVID-19 and its related severity and outcome in normal subjects emphasizing the pivotal role of ACE2. Therefore, the primary purpose of this study was to investigate the involved mechanisms of ACE2 protein and other risk factors causing infection in different situations and finally, to introduce a safe, accurate, and cost-effective approach to prevent SARS-COV-2 infection and hard clinical outcomes in normal subjects.

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EXPERIENCE IN CONSTRUCTION OF HORIZONTAL WELLS AT THE KOSHILSKOYE OIL FIELD

Oil and Gas Studies ◽

10.31660/0445-0108-2018-4-34-37 ◽

2018 ◽

pp. 34-37

Author(s):

N. A. Aksenova ◽

E. Yu. Lipatov ◽

T. A. Haritonova

Keyword(s):

Horizontal Wells ◽

Cost Effective ◽

Oil Field ◽

Drilling Mud ◽

Environmentally Safe

The article presents the experience of drilling horizontal wells at the Koshilskoye oil field in Jurassic sediments (UV1 formation) with application of environmentally safe emulsion drilling mud system BARADRIL-N XP-07 which has proved cost-effective.

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Silver Nanoparticles: Properties, Synthesis, Characterization, Applications and Future Trends

10.5772/intechopen.99173 ◽

2021 ◽

Author(s):

Sunil T. Galatage ◽

Aditya S. Hebalkar ◽

Shradhey V. Dhobale ◽

Omkar R. Mali ◽

Pranav S. Kumbhar ◽

...

Keyword(s):

Silver Nanoparticles ◽

Metallic Nanoparticles ◽

Large Scale ◽

Cost Effective ◽

Nano Particles ◽

Scale Production ◽

Green Technologies ◽

Synthesis Of Nanoparticles ◽

Vital Importance ◽

Environmentally Safe

Nanotechnology is an expanding area of research where we use to deal with the materials in Nano-dimension. The conventional procedures for synthesizing metal nanoparticles need to sophisticated and costly instruments or high-priced chemicals. Moreover, the techniques may not be environmentally safe. Therefore “green” technologies for synthesis of nanoparticles are always preferred which is simple, convenient, eco-friendly and cost effective. Green synthesis of nanoparticle is a novel way to synthesis nanoparticles by using biological sources. It is gaining attention due to its cost effective, ecofriendly and large scale production possibilities. Silver nanoparticles (AgNPs) are one of the most vital and fascinating nanomaterials among several metallic nanoparticles that are involved in biomedical applications. It has vital importance in nanoscience and naomedicines to treat and prevent vital disease in human beings especially in cancer treatment. In current work we discussed different methods for synthesis of AgNPs like biological, chemical and physical along with its characterization. We have also discussed vital importance of AgNPs to cure life threatnign diseases like cancer along with antidiabetic, antifungal, antiviral and antimicrobial alog with its molecular mode of action etc. Finally we conclude by discussing future prospects and possible applications of silver nano particles.

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Adhesion and Electrical Insulation of Thin Polymeric Coatings Under Saline Exposure

MRS Proceedings ◽

10.1557/proc-110-627 ◽

1987 ◽

Vol 110 ◽

Cited By ~ 3

Author(s):

R. N. Leyden ◽

D. I. Basiulis

Keyword(s):

Barrier Properties ◽

Peel Strength ◽

Polymer Coatings ◽

Polymeric Coatings ◽

Adhesive Failure ◽

Short Term ◽

Leakage Currents ◽

Electrical Bias ◽

Implanted Devices

AbstractA study was made of the adhesion of insulating polymer coatings under long term exposure to electrical bias. Since a common mode of failure in implanted devices is the penetration of water into poorly adhering insulation/conductor interfaces followed by electrolytic degradation, development of processes, primers, and insulators with good adhesion that resist the effects of water were sought. Polyimide coatings were tested for their ion barrier properties by immersion of insulated comb patterns in saline with 9 V D.C. bias between the comb fingers. Leakage currents, measured over three years exposure, increased from several picoamps initially to several nanoamps in surviving specimens. Subsequent studies showed that dramatic improvements in the moisture durability of the adhesion could be obtained using Hitachi's aluminum chelate type primer. Whereas the peel strength of polyimide on unprimed platinum fell more than 90% after several hours of boiling saline exposure, the peel strength of polyimide coatings on primed surfaces remained at over 80% of their initial values. ESCA analysis of the peel interfaces showed that both aluminum oxide and polyimide remain on the substrate after peeling back the polyimide. This suggests a combination of cohesive and adhesive failure at the primer/polyimide interface. The effects of exposure of the polymer/substrate interfaces (edges) to saline and electrochemical stress were examined by patterning circular openings in the polyimide. A 10 V anodic potential was found to damage adhesion to titanium as far as 75 microns away from the edge. Pulsing at 500 Hz, 1 V peak to peak was found to have no measurable effect in the short term.

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Porous Polymer Coatings Based on Nitrocellulose

Materials Science Forum ◽

10.4028/www.scientific.net/msf.968.68 ◽

2019 ◽

Vol 968 ◽

pp. 68-75

Author(s):

Valeriy Vyrovoy ◽

Viacheslav Bachynckyi ◽

Nadia Antoniuk

Keyword(s):

Porous Structure ◽

Cellular Structure ◽

Polymer Coating ◽

Experimental Studies ◽

Polymer Coatings ◽

Porous Polymer ◽

Polymeric Coatings ◽

New Approach ◽

Porous Coatings

The paper presents the development of optimum structures and the production of polymeric coatings technology which can absorb aggressive substances. The studies of coatings penetrating into the film are presented due to the organization of their capillary-cellular structure by introducing special fillers. A new approach to solve the problem of protecting the environment, people, buildings and structures from the effects of aggressive substances has been proposed. The essence of the method consists in the preventive deposition on the surfaces of construction objects of porous coatings that can irreversibly absorb aggressive substances. Based on theoretical and experimental studies, porous coatings have been developed that are capable of accumulating in their volume aggressive substances, as well as certain principles of providing the coating with the necessary capillary-porous structure. The mechanism of creating a capillary-cellular structure of a polymer coating based on nitrocellulose are substantiated.

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Towards High Performance Chemical Vapour Deposition V2O5 Cathodes for Batteries Employing Aqueous Media

Molecules ◽

10.3390/molecules25235558 ◽

2020 ◽

Vol 25 (23) ◽

pp. 5558

Author(s):

Dimitra Vernardou ◽

Charalampos Drosos ◽

Andreas Kafizas ◽

Martyn E. Pemble ◽

Emmanouel Koudoumas

Keyword(s):

Energy Storage ◽

High Performance ◽

Large Scale ◽

Electrode Materials ◽

Low Cost ◽

Aqueous Media ◽

Chemical Vapour ◽

Cost Effective ◽

Scale Production ◽

Environmentally Safe

The need for clean and efficient energy storage has become the center of attention due to the eminent global energy crisis and growing ecological concerns. A key component in this effort is the ultra-high performance battery, which will play a major role in the energy industry. To meet the demands in portable electronic devices, electric vehicles, and large-scale energy storage systems, it is necessary to prepare advanced batteries with high safety, fast charge ratios, and discharge capabilities at a low cost. Cathode materials play a significant role in determining the performance of batteries. Among the possible electrode materials is vanadium pentoxide, which will be discussed in this review, due to its low cost and high theoretical capacity. Additionally, aqueous electrolytes, which are environmentally safe, provide an alternative approach compared to organic media for safe, cost-effective, and scalable energy storage. In this review, we will reveal the industrial potential of competitive methods to grow cathodes with excellent stability and enhanced electrochemical performance in aqueous media and lay the foundation for the large-scale production of electrode materials.

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The Australian Roadkill Reporting Project—Applying Integrated Professional Research and Citizen Science to Monitor and Mitigate Roadkill in Australia

Animals ◽

10.3390/ani10071112 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1112

Author(s):

Bruce Englefield ◽

Melissa Starling ◽

Bethany Wilson ◽

Caidyrn Roder ◽

Paul McGreevy

Keyword(s):

Population Dynamics ◽

Citizen Science ◽

Value Added ◽

Cost Effective ◽

Mitigation Measures ◽

Activity Levels ◽

Significant Finding ◽

The Public ◽

Distribution Mapping ◽

Professional Research

Australia has no national roadkill monitoring scheme. To address this gap in knowledge, a roadkill reporting application (app) was developed to allow members of the public to join professional researchers in gathering Australian data. The app is used to photograph roadkill and simultaneously records the GPS location, time and date. These data are uploaded immediately to a website for data management. To illustrate the capacity to facilitate cost-effective mitigation measures the article focuses on two roadkill hotspots—in Queensland and Tasmania. In total, 1609 reports were gathered in the first three months of the project. They include data on mammals (n = 1203, 75%), birds (n = 125, 7.8%), reptiles (n = 79, 4.9%), amphibians (n = 4, 0.025%), unidentified (n = 189, 11.8%) and unserviceable ones (n = 9). A significant finding is variance in the distribution of mammals and birds at different times of day. These findings reflect diurnal variation in the activity levels of different species and underline the need for data on a targeted species to be collected at appropriate times of day. By continuing to facilitate roadkill monitoring, it is anticipated that the data generated by the app will directly increase knowledge of roadkill numbers and hotspots. Indirectly, it will provide value-added information on animal behaviour, disease and population dynamics as well as for species distribution mapping.

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Antifouling Napyradiomycins from Marine-Derived Actinomycetes Streptomyces aculeolatus

Marine Drugs ◽

10.3390/md18010063 ◽

2020 ◽

Vol 18 (1) ◽

pp. 63 ◽

Cited By ~ 5

Author(s):

Florbela Pereira ◽

Joana R. Almeida ◽

Marisa Paulino ◽

Inês R. Grilo ◽

Helena Macedo ◽

...

Keyword(s):

Mytilus Galloprovincialis ◽

Cost Effective ◽

In Silico Prediction ◽

Antifouling Activity ◽

Marine Biofouling ◽

Immersed Surfaces ◽

Madeira Archipelago ◽

Order Of Magnitude ◽

Environmentally Safe ◽

Approved Drugs

The undesired attachment of micro and macroorganisms on water-immersed surfaces, known as marine biofouling, results in severe prevention and maintenance costs (billions €/year) for aquaculture, shipping and other industries that rely on coastal and off-shore infrastructures. To date, there are no sustainable, cost-effective and environmentally safe solutions to address this challenging phenomenon. Therefore, we investigated the antifouling activity of napyradiomycin derivatives that were isolated from actinomycetes from ocean sediments collected off the Madeira Archipelago. Our results revealed that napyradiomycins inhibited ≥80% of the marine biofilm-forming bacteria assayed, as well as the settlement of Mytilus galloprovincialis larvae (EC50 < 5 µg/ml and LC50/EC50 >15), without viability impairment. In silico prediction of toxicity end points are of the same order of magnitude of standard approved drugs and biocides. Altogether, napyradiomycins disclosed bioactivity against marine micro and macrofouling organisms, and non-toxic effects towards the studied species, displaying potential to be used in the development of antifouling products.

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