Hazardous Materials from Threats to Safety: Molecularly Imprinted Polymers as Versatile Safeguarding Platforms.

Hazards associated with highly dangerous pollutants/contaminants in water, air, and land resources, as well as food, are serious threats to public health and the environment. Thus, it is imperative to detect or decontaminate, as risk-control strategies, the possible harmful substances sensitively and efficiently. In this context, due to their capacity to be specifically designed for various types of hazardous compounds, the synthesis and use of molecularly imprinted polymers (MIPs) have become widespread.

Dual-Responsive Hydrogels for Mercury Ion Detection and Removal from Wastewater.

This study describes the development of a fast and cost-effective method for the detection and removal of Hg ions from aqueous media, consisting of hydrogels incorporating chelating agents and a rhodamine derivative (to afford a qualitative evaluation of the heavy metal entrapment inside the 3D polymeric matrix). These hydrogels, designed for the simultaneous detection and entrapment of mercury, were obtained through the photopolymerization of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPSA) and N-vinyl-2-pyrrolidone (NVP), utilizing N,N'-methylenebisacrylamide (MBA) as crosslinker, in the presence of polyvinyl alcohol (PVA), a rhodamine B derivative, and one of the following chelating agents: phytic acid, 1,3-diamino-2-hydroxypropane-tetraacetic acid, triethylenetetramine-hexaacetic acid, or ethylenediaminetetraacetic acid disodium salt. The rhodamine derivative had a dual purpose in this study: firstly, it was incorporated into the hydrogel to allow the qualitative evaluation of mercury entrapment through its fluorogenic switch-off abilities when sensing Hg ions; secondly, it was used to quantitatively evaluate the level of residual mercury from the decontaminated aqueous solutions, via the UV-Vis technique.

Nanocomposite Hydrogel Films Based on Sequential Interpenetrating Polymeric Networks as Drug Delivery Platforms.

In this study, novel materials have been obtained via a dual covalent and ionic crosslinking strategies, leading to the formation of a fully interpenetrated polymeric network with remarkable mechanical performances as drug delivery platforms for dermal patches. The polymeric network was obtained by the free-radical photopolymerization of N-vinylpyrrolidone using tri(ethylene glycol) divinyl ether as crosslinker in the presence of sodium alginate (1%, weight%). The ionic crosslinking was achieved by the addition of Zn, ions which were coordinated by the alginate chains.

Nafcillin-Loaded Photocrosslinkable Nanocomposite Hydrogels for Biomedical Applications.

Skin infections are frequently treated via intravenous or oral administration of antibiotics, which can lead to serious adverse effects and may sometimes contribute to the proliferation of resistant bacterial strains. Skin represents a convenient pathway for delivering therapeutic compounds, ensured by the high number of blood vessels and amount of lymphatic fluids in the cutaneous tissues, which are systematically connected to the rest of the body. This study provides a novel, straightforward method to obtain nafcillin-loaded photocrosslinkable nanocomposite hydrogels and demonstrates their performance as drug carriers and antimicrobial efficacy against Gram-positive bacteria.

"Green" PBX Formulations Based on High Explosives (RDX and HMX) and Water-Soluble pH-Sensitive Polymeric Binders.

The increasingly harsher and more complex international and European environmental legislation drives the current development of "greener" energetics materials and munitions. The aerospace and defense industries rely on extensive research in the formulation and scale-up production of polymer-bonded explosives (PBX). In this context, this paper aims to present a versatile method for obtaining "green" PBX formulations based on two high explosives (hexogen (RDX) and octogen (HMX)) and acrylic acid-ethyl acrylate copolymeric binders.

Effect of Aromatic Chain Extenders on Polyurea and Polyurethane Coatings Designed for Defense Applications.

The present work describes the synthesis of new versatile polyurea (PU) and polyurethane (PUR) matrices, including different chain extenders, which facilitate the design of distinct, tunable properties, and high-performance derivatives. These polymers can be used for various defense and security applications, such as coatings for ballistic protection, CBRN protection, binders for energetic formulations, etc. Combining aliphatic and aromatic molecules in PU or PUR structures enables the synthesis of polymers with improved and controllable thermo-mechanical properties.

The Influence of Potassium Salts Phase Stabilizers and Binder Matrix on the Properties of Novel Composite Rocket Propellants Based on Ammonium Nitrate.

The environmental impact and availability of ingredients are vital for the new generation of rocket propellants. In this context, several novel composite propellants were prepared based on the "greener" oxidizer (PSAN), a micronized aluminum-magnesium alloy fuel, iron oxide powder burn rate modifier, triethylene glycol dinitrate (TEGDN) energetic plasticizer and a polyurethane (PU) binder. The novelty of this study is brought by the innovative procedure of synthesizing and combining the constituents of these heterogeneous compositions to obtain high-performance "eco-friendly" rocket propellants.

Peelable Nanocomposite Coatings: "Eco-Friendly" Tools for the Safe Removal of Radiopharmaceutical Spills or Accidental Contamination of Surfaces in General-Purpose Radioisotope Laboratories.

Radioactive materials are potentially harmful due to the radiation emitted by radionuclides and the risk of radioactive contamination. Despite strict compliance with safety protocols, contamination with radioactive materials is still possible. This paper describes innovative and inexpensive formulations that can be employed as 'eco-friendly' tools for the safe decontamination of radiopharmaceuticals spills or other accidental radioactive contamination of the surfaces arising from general-purpose radioisotope handling facilities (radiopharmaceutical laboratories, hospitals, research laboratories, etc.

Strippable Polymeric Nanocomposites Comprising "Green" Chelates, for the Removal of Heavy Metals and Radionuclides.

The issue of heavy metal and radionuclide contamination is still causing a great deal of concern worldwide for environmental protection and industrial sites remediation. Various techniques have been developed for surface decontamination aiming for high decontamination factors (DF) and minimal environmental impact, but strippable polymeric nanocomposite coatings are some of the best candidates in this area. In this study, novel strippable coatings for heavy metal and radionuclides decontamination were developed based on the film-forming ability of polyvinyl alcohol, with the remarkable metal retention capacity of bentonite nanoclay, together with the chelating ability of sodium alginate and with "new-generation" "green" complexing agents: iminodisuccinic acid (IDS) and 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC).

Eco-Friendly Peelable Active Nanocomposite Films Designed for Biological and Chemical Warfare Agents Decontamination.

In the context of imminent threats concerning biological and chemical warfare agents, the aim of this study was the development of a new method for biological and chemical decontamination, employing non-toxic, film-forming, water-based biodegradable solutions, using a nano sized reagent together with bentonite as trapping agents for the biological and chemical contaminants. Bentonite-supported nanoparticles of Cu, TiO, and Ag were successfully synthesized and dispersed in a polyvinyl alcohol ()/glycerol () aqueous solution. The decontamination effectiveness of the proposed solutions was evaluated by qualitative and quantitative analytical techniques on various micro-organisms, with sulfur mustard () and dimethyl methylphosphonate () as contaminants.

Novel Polyurethanes Based on Recycled Polyethylene Terephthalate: Synthesis, Characterization, and Formulation of Binders for Environmentally Responsible Rocket Propellants.

Novel polyurethane-based binders, specifically designed for environmentally responsible rocket propellant composites, were obtained by employing the polyester-polyols that resulted from the degradation of polyethylene terephthalate waste. A new class of "greener" rocket propellants, comprising polyurethanes (based on recycled PET) as the binder, phase stabilized ammonium nitrate (PSAN) as the eco-friendly oxidizer, and triethylene glycol dinitrate (TEGDN) as the energetic plasticizer, together with aluminum as fuel and FeO as the catalyst, is herein reported. The components of the energetic mixtures were investigated (individually and as composite materials) through specific analytical tools: H-NMR, FT-IR, SEM-EDX, DTA and TGA, tensile and compression tests, DMA, and micro-CT.

Decontamination of radioactive hazardous materials by using novel biodegradable strippable coatings and new generation complexing agents.

Eight different types of complexing agents were employed for the development of new biodegradable decontamination solutions that are able to form strippable coatings after they are dispersed and allowed to dry on a variety of surfaces contaminated with Co, Ba, Cs and Am radioactive isotopes. The new generation of eco-friendly chelators with superior biodegradability, utilized for the first time in such applications, can easily replace the non-biodegradable and carcinogenic complexing agents that are still in use today, due to their decontamination performances. Furthermore, besides the complexing action over the radionuclides, the solutions contain two types of clays, Bentonite (BT) and Saponite (SP), which have the capacity to adsorb specific ions, improving the decontamination efficiency of the solutions.

Reducing impacts from ammunitions: A comparative life-cycle assessment of four types of 9mm ammunitions.

Increase of environmental awareness of the population has pressured research activities in the defence area to cover environment and toxicity issues, where have been considered appropriate manners to reduce the environmental and toxicological impacts of ammunition. One of the adopted approaches to achieve such goal involves the replacement of lead and other heavy metals by alternative materials. However, the consequences of using alternative materials in ammunitions manufacturing are uncertain for the other life-cycle phases and trade-offs can occur.

Novel formulations of ballistic gelatin. 1. Rheological properties.

Ballistic gelatin is the simulant of the human body during field tests in forensics and other related fields, due to its physical and mechanical similarities to human trunk and organs. Since the ballistic gelatin used in present has important issues to overcome, an alternative approach is the use of gelatin-polymer composites, where a key factor is the insertion of biocompatible materials, which replicate accurately the human tissues. In order to be able to obtain an improved material in terms of mechanical performances by an easy industrial-scale technology, before the verification of the ballistic parameters by shooting in agreement with military standards, one of the best and cheapest solutions is to perform a thorough check of their rheological properties, in standard conditions.

Poly(2-hydroxyethyl methacrylate-co-dodecyl methacrylate-co-acrylic acid): synthesis, physico-chemical characterisation and nafcillin carrier.

In the present study polymeric microbeads of poly(2-hydroxyethyl methacrylate-co-dodecyl methacrylate-co-acrylic acid) or p(HEMA-co-dDMA-co-AA) were synthesised and characterized through FT-IR and scanning electron microscopy (SEM); their swelling behavior against saline solution was explored and their in vitro cytotoxicity was evaluated. Further, in order to elucidate kinetic aspects regarding the ternary system p(HEMA-co-dDMA-co-AA), a mathematical model of the reactivity ratios of the comonomers in the terpolymer has been conceived and analyzed. An intensified tendency of AA units accumulation in the copolymer has been noticed, in spite of HEMA units, while dDMA conserves in the copolymer the fraction from the feed.