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Microplastics (MPs) and nanoplastics (NPs) have emerged as significant environmental pollutants with potential detrimental effects on ecosystems and human health. Several studies indicate their interaction with enzymes; this topic represents a multifaceted research field encompassing several areas of interest from the toxicological and ecotoxicological impact of MPs and NPs on humans and wildlife to the biodegradation of plastics by microbial enzymes. This review aims to provide a critical analysis of the state-of-the-art knowledge of the interaction of MPs and NPs on the enzyme carbonic anhydrase (CA), providing recent insights, analyzing the knowledge gaps in the field, and drawing future perspectives of the research and its application. CA is a widespread and crucial enzyme in various organisms; it is critical for various physiological processes in animals, plants, and bacteria. It catalyzes the reversible hydration of CO2, which is essential for respiration, acid–base balance, pH homeostasis, ion transport, calcification, and photosynthesis. Studies demonstrate that MPs and NPs can inhibit CA activity with mechanisms including adsorption to the enzyme surface and subsequent conformational changes. In vitro and in silico studies highlight the role of electrostatic and hydrophobic interactions in these processes. In vivo studies present mixed results, which are influenced by factors like particle type, size, concentration, and organism type. Moreover, the potentiality of the esterase activity of CA for plastic degradation is discussed. The complexity of the interaction between CA and MPs/NPs underscores the need for further research to fully understand the ecological and health impacts of MPs and NPs on CA activity and expression and glimpses of the potentiality and perspectives in this field. [ABSTRACT FROM AUTHOR]

Highlights One of the main issues in epoxy‐based composite manufacturing is the formation of porosity derived from moisture absorption during storage and layup due to the high hydrophilicity of epoxy matrices. During the curing process, the presence of moisture and other volatile compounds can initiate the nucleation and growth of voids. In this study, the effect of both the initial water content absorbed in the uncured resin and the pressure on the porosity development in an epoxy resin was investigated. In particular, Kardos' and Ledru's models, aimed at predicting void formation in polymers, were applied to study the effect of different hydrostatic pressures in an epoxy resin during curing up to the gel point, after conditioning it at two different relative humidity levels, 50% and 95%. Subsequently, the porosity of the cured resin samples was quantified through density measurements. Comparative analysis of the microscopy images of cured samples and the predictions of both models revealed an overestimation of the final void sizes by both models, with the Kardos' model exhibiting a higher deviation. Additionally, a finite element model was employed to investigate the conditions leading to void formation, aiming to understand the factors influencing the porosity development and properly set the process parameters during composite manufacturing. Evaluation of the conditions leading to void growth in epoxy resin during curing Moisture sorption in uncured epoxy resin Effect of curing pressure on pore development Finite element analysis for void growth during resin curing [ABSTRACT FROM AUTHOR]

In this work, a general method to predict the stiffness tensor of short‐fiber composites as a function of the fabric tensor (i.e. the tensor describing the architectural anisotropy of the micro‐structure), determined by X‐ray computed tomography, is presented. The proposed method does not depend on the type of fabric tensor used to characterize the symmetry properties of the composite. The experimental data used for method validation were obtained from thermoplastic composite matrices reinforced with short carbon and basalt fibers. The components of the stiffness tensor were calculated using the Mori‐Tanaka model and the Halpin‐Tsai equation for the stiffness of aligned short‐fiber composites, but other micromechanics models could be used as well. The statistical alignment of the fibers in each portion of the sample was measured by determining the principal axes of the fabric tensor. The average properties calculated on sub‐volumes provided moduli values in very good agreement with those determined experimentally. This approach is very general and easy to implement and does not need any numerical analysis tools. [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution represents one of the biggest environmental problems that is further exacerbated by the continuous degradation in the marine environment of MPs to nanoplastics (NPs). The most diffuse plastics in oceans are commodity polymers, mainly thermoplastics widely used for packaging, such as polyethylene terephthalate (PET). However, the huge interest in the chemical vector role of micro/nanoplastics, their fate and negative effects on the environment and human health is still under discussion and the research is still sparse due also to the difficulties of sampling MPs and NPs from the environment or producing NPs in laboratory. Moreover, the research on MPs and NPs pollution relies on the availability of engineered nanoparticles similar to those present in the marine environment for toxicological, transport and adsorption studies in biological tissues as well as for wastewater remediation studies. This work aims to develop an easy, fast and scalable procedure for the production of representative model nanoplastics from PET pellets. The proposed method, based on a simple and economic milling process, has been optimized considering the peculiarities of the polymer. The results demonstrated the reliability of the method for preparing particle suspensions for aquatic microplastic research, with evident advantages compared to the present literature procedures, such as low cost, the absence of liquid nitrogen, the short production time, the high yield of the process, stability, reproducibility and polydisperse size distribution of the produced water dispersed nanometric PET. [ABSTRACT FROM AUTHOR]