Acrylate and Methacrylate Polymers’ Applications: Second Life with Inexpensive and Sustainable Recycling Approaches

Polymers are widely employed in several fields thanks to their wide versatility and the easy derivatization routes. However, a wide range of commercial polymers suffer from limited use on a large scale due to their inert nature. Nowadays, acrylate and methacrylate polymers, which are respectively derivatives of acrylic or methacrylic acid, are among the most proposed materials for their useful characteristics like good biocompatibility, capping ability toward metal clusters, low price, potentially recyclability and reusability. Here, we discuss the advantages and challenges of this class of smart polymers focusing our attention on their current technological applications in medical, electronic, food packaging and environmental remediation fields. Furthermore, we deal with the main issue of their recyclability, considering that the current commercial bioplastics are not yet able to meet the global needs as much as to totally replace fossil-fuel-based products. Finally, the most accredited strategies to reach recyclable composites based on acrylic polymers are described.

Metal-Organic Framework Reinforced Acrylic Polymer Marine Coatings

Metal-organic frameworks (MOFs), a class of crystalline, porous, 3D materials synthesized by the linking of metal nodes and organic linkers are rapidly emerging as attractive materials in gas storage, electrodes in batteries, super-capacitors, sensors, water treatment, and medicine etc. However the utility of MOFs in coatings, especially in marine coatings, has not been thoroughly investigated. In this manuscript we report the first study on silver MOF (Ag-MOF) functionalized acrylic polymers for marine coatings. A simple and rapid microwave technique was used to synthesize a two-dimensional platelet structured Ag-MOF. Field tests on the MOF reinforced marine coatings exhibited an antifouling performance, which can be attributed to the inhibition of marine organisms to settle as evidenced by the anti-bacterial activity of Ag-MOFs. Our results indicate that MOF based coatings are highly promising candidates for marine coatings.

Effect of Various Types of Superplasticisers on Consistency, Viscosity, Structure and Long-Term Strength of Geopolymer Products

This article presents the results of research on the effect of plasticisers made based on four different compounds—melamine (M), naphthalene (NF), acrylic polymers (AP) and polycarboxylic ethers (PC)—added to the tested mixes in the amount of 2% of the fly ash (FA). The influence of superplasticisers (SPs) on the consistency of the fresh concrete was investigated using a flow table and a penetrometer, and the air voids content was determined by means of a porosimeter. Additionally, the influence of plasticisers on the viscosity of the paste was investigated using a rheometer. Hardened mortar that matured under two different conditions was also tested at elevated and room temperatures. The tested properties were 7-, 28- and 90-days compressive strength and internal microstructure viewed under a microscope. NF had the greatest viscosity-reducing effect while it increased the air void volume in the mix at the same time. The highest early and late strengths were obtained after curing in elevated temperature samples with an acrylic-polymer-based superplasticiser. However, the increased curing temperature of the samples only influenced the early strength results. Its effect was not visible after 90 days. The AP addition also had a significant impact on improving the consistency of the mixture. The addition of plasticisers did not affect the microstructure of the specimens.

Predicting the Swelling Behavior of Acrylic Superabsorbent Polymers Used in Diapers

Acrylic polymer is a superabsorbent for water and widely used in diapers, in which its swelling behavior can be significantly affected by several factors, i.e., the time, temperature, pH, and salt concentration, and thus the product performance in the applications. In this work, the water absorption behavior of acrylic superabsorbent polymers by each of these individual factors was investigated. The results showed that the water absorbency increases with the pH in the range of 2 to ~7 and decreases when the pH continues to increase. However, it decreases with the increases in NaCl concentration in the solution. Moreover, more water can be absorbed by the acrylic polymers at the higher temperature. Based on a previously developed kinetic swelling model and the information from the above investigations, a semiempirical model for predicting the swelling behavior of superabsorbent polymers (SAPs) under different conditions has been developed. Data showed that the model can predict (with a relative error of <4.5%) the amount of water absorbed by acrylic SAPs under different swelling conditions. The model would be very helpful to the practical application in both product design and its performance evaluation.

Waterproofing of primary lining in tunnel using nano chemicals and soil modifiers in Concrete

The use of waterproofing chemicals in the field of concrete technology has proven a significant boom in the civil engineering industry by increasing the life of concrete structures. The materials such as nano-acrylic polymers resulted, significant control over the water leakage and damping conditions especially Terrasil and Zycobond and various nano sealers such as Zycoprime+ and Zycosil+. In this study, the primary focus is to waterproof tunnels using the various acrylic, nano-technological, and soil modifier chemicals to stabilize the tunnel structure in areas of hilly terrain. The use of these chemicals has been sourced in other areas of application but the least glance is seen in the field of tunnel engineering. These chemicals bind with the concrete and form a hydrophobic layer thus decreasing the permeability of concrete structure. In the present study the percentage of Zycobond and Terrasil used was 1.5% by weight of concrete and the ratio for Zs+:Zp+:water was 1:2:20. Tunnels especially in hilly terrain pass the flowing streams, thus making it more prone to damping conditions. So, poor site conditions result in less durability of concrete as well as steel, therefore improvement in engineering properties using these chemicals is primarily sought out in this paper. The factors considered during the use were the permeability, strength, volumetric analysis of chemicals, material properties etc. Water-proofing the concrete improves various engineering properties such as permeability, compressive strength, durability, strength, and various other properties of Concrete. The study emphasized to gauge the viability of Zycosil+ and Zycoprime+, Terrasil and Zycobond as waterproofing agents in concrete.

Tuning the Activity of a Hybrid Polymer–Oxocluster Catalyst: A Composition—Selectivity Correlation

Zr-based oxoclusters MxOy(OR)w(OOR’)z are promising catalysts for the activation of hydrogen peroxide. However, they need to be integrated into suitable matrices to increase their hydrolytic stability and allow for their recovery after use. Polymeric materials can be successfully employed for this aim, since they modify the properties of the resulting hybrid materials, in terms of polarity and chemical affinity for the substrates, improving the catalytic activity. Herein, we report the synthesis of different acrylic polymers based on various co-monomers (methyl methacrylate (MMA), 2,2,2-trifluoroethylmethacrylate (TFMA) and 3-methacryloxypropyltrimethoxylsilane (MAPTMS)) covalently cross-linked by a Zr4-based oxocluster, whose composition was tuned to optimise the catalytic oxidation of methyl p-tolyl sulphide. To assess their properties and stability, the materials were characterised via Fourier Transform Infrared (FT-IR) and Raman spectroscopies, Thermogravimetric Analysis (TGA), Solid-State NMR (SS-NMR) and X-Ray Absorption Spectroscopies XAS, before and after catalytic turnover.

Failure Modes for Acrylic Polymers in Section VIII Pressure Vessels

Section VIII of the Boiler and Pressure Vessel Code is introducing the use of acrylics as a pressure vessel material. The design method is specified in ASME PVHO-1, Safety Standard for Pressure Vessels for Human Occupancy. The current method relies upon an empirical method developed in the 1960–70’s. It does not use “allowable stress” or other mechanical properties traditionally used to calculate design dimensions, but instead uses a fixed range of dimensions for specific shapes and determines the wall thickness using a curve. Understanding the PVHO-1 design assumptions and typical failure modes is important for a non-PVHO pressure vessel designer using acrylics. An ASME Codes & Standards task group is developing a “design by analysis” method (DBA) for acrylics and other glassy polymers for pressure vessel components. The proposed DBA methodology uses Verification and Validation (V&V) techniques and Finite Element Method (FEM) as the design method framework in order to advance the use of glassy polymers as pressure vessel materials.

The effect of combination of functional and nonfunctional acrylic polymers on transdermal patches of : in vitro permeation, in vivo evaluation using biochemical parameters, and stability studies

Background A double-layer transdermal drug-in-adhesive patch of carvedilol was developed using functional and nonfunctional grades of acrylic adhesives, DURO-TAK® 387-2051, DURO-TAK® 387-2510, and DURO-TAK® 87-4098. The patch was designed to provide adequate permeation of the drug up to 2 days, with effective adhesion attributes. An optimized formulation was selected, the effect of the combination was studied and a 180° peel strength test was performed to evaluate adhesive properties. Further, the patch was assessed for in vivo studies on basis of biochemical parameters, skin irritation, and stability studies. The stability study was carried out on optimized fresh (S1) and 6 months old patches stored at room, and accelerated condition (40 ± 2 °C/75 ± 5% RH) using FTIR, DSC, and SEM techniques. Result It was studied that the steady-state flux (Jss) or permeation rate of the drug through excised rat skin has relied on the nature of acrylic and the combination of acrylic polymers. The TDDS containing –OH functional group DT 387-2510 with nonfunctional pressure-sensitive adhesives (PSAs) DT 87-4098, with Span 80 as penetration enhancer exhibited maximum flux (19.12 ± 0.64 μg/cm2/h) and form homogeneous and stable blends, controlling permeation of drug at a desired steady rate for 48 h. The data obtained from in vivo studies using biochemical parameters suggested that there were no statistical differences observed in results for the control and treated group while analyzing observations for serum creatinine, glucose test, sodium test, albumin, and potassium (p > 0.05). Also, the optimized formulation showed no sign of localized reactions and was confirmed by a skin histological study indicating the formulation was safe and compatible with the skin. A significant shift of peaks was not observed in FTIR spectra and DSC thermograms of the patches after the stability period. Conclusion The investigation reveals that the drug-in-adhesive patch of carvedilol, by a combination of functional and nonfunctional PSAs, provides a good and effective option for controlled delivery of carvedilol. From our findings, it has been concluded that drug in the adhesive patch has been able to provide satisfactory adhesion, drug uniformity, drug permeation, marked positive biochemical results, and good stability.

Effect of UV Radiation on Optical Properties and Hardness of Transparent Wood

Optically transparent wood is a type of composite material, combining wood as a renewable resource with the optical and mechanical properties of synthetic polymers. During this study, the effect of monochromatic UV-C (λ—250 nm) radiation on transparent wood was evaluated. Samples of basswood were treated using a lignin modification method, to preserve most of the lignin, and subsequently impregnated with refractive-index-matched types of acrylic polymers (methyl methacrylate, 2-hydroxyethyl methacrylate). Optical (transmittance, colour) and mechanical (shore D hardness) properties were measured to describe the degradation process over 35 days. The transmittance of the samples was significantly decreased during the first seven days (12% EMA, 15% MMA). The average lightness of both materials decreased by 10% (EMA) and 17% (MMA), and the colour shifted towards a red and yellow area of CIE L*a*b* space coordinates. The influence of UV-C radiation on the hardness of the samples was statistically insignificant (W+MMA 84.98 ± 2.05; W+EMA 84.89 ± 2.46), therefore the hardness mainly depends on the hardness of used acrylic polymer. The obtained results can be used to assess the effect of disinfection of transparent wood surfaces with UV-C radiation (e.g., due to inactivation of SARS-CoV-2 virus) on the change of its aesthetic and mechanical properties.