Improving the Elastic Response of Tanned Leather by Treatment with a Carboxylic Elastomer.

The elastic response of chromium-tanned leather was successfully improved by treatment with XSBR, a carboxylated styrene-butadiene copolymer. The carboxylic groups pending from a styrene-butadiene rubber (SBR) backbone were found to promote penetration of the aqueous polymer dispersion into the fibrous tanned leather and participated in pH-reversible physical crosslinking by H-bonding. The different penetrations of XSBR or SBR were investigated using a micro-FTIR cross-sectional analysis from the grain (outer) to the flesh (inner) side of 18 wt% elastomer-treated samples, based on the shaved leather weight.

Natural iron-containing minerals catalyze the degradation of polypropylene microplastics: a route to self-remediation learnt from the environment.

Virgin and environmentally aged polypropylene (PP) micropowders (V-PP and E-PP, respectively) were used as reference microplastics (MPs) in comparative photo- and thermo-oxidative ageing experiments performed on their mixtures with a natural ferrous sand (NS) and with a metal-free silica sand (QS). The ferrous NS was found to catalyze the photo-oxidative degradation of V-PP after both UV and simulated solar light irradiation. The catalytic activity in the V-PP/NS mixture was highlighted by the comparatively higher fraction of photo-oxidized PP extracted in dichloromethane, and the higher carbonyl index of the bulk polymer extracted with boiling xylene, when compared with the V-PP/QS mixture.

Additive Manufacturing of Wet-Spun Polysulfone Medical Implants.

Research on additive manufacturing (AM) of high-performance polymers provides novel materials and technologies for advanced applications in different sectors, such as aerospace and biomedical engineering. The present article is contextualized in this research trend by describing a novel AM protocol for processing a polysulfone (PSU)/-methyl-2-pyrrolidone (NMP) solution into medical implant prototypes. In particular, an AM technique involving the patterned deposition of the PSU/NMP mixture in a coagulation bath was employed to fabricate PSU implants with different predefined shape, fiber diameter, and macropore size.

The role of early synthetic materials degradation in the downfall of the Ansaldo A.1, an Italian World War I biplane fighter.

From the Pioneer Era of the aviation to World War I the evolution of aircraft technology and chemical synthesis enabled a unique coexistence of traditional craftsmanship, artistic decoration practices, and technological advancements. The study of the materials used in these early years of aviation is still an uncharted territory: a vast portion of remaining planes has been partially or completely repaired and restored, usually by total replacement of the fabric. The Italian biplane Ansaldo A.

Microplastic pollution in the sediments of interconnected lakebed, seabed, and seashore aquatic environments: polymer-specific total mass through the multianalytical "PISA" procedure.

The total mass of individual synthetic polymers present as microplastic (MP < 2 mm) pollutants in the sediments of interconnected aquatic environments was determined adopting the Polymer Identification and Specific Analysis (PISA) procedure. The investigated area includes a coastal lakebed (Massaciuccoli), a coastal seabed (Serchio River estuarine), and a sandy beach (Lecciona), all within a natural park area in Tuscany (Italy). Polyolefins, poly(styrene) (PS), poly(vinyl chloride) (PVC), polycarbonate (PC), poly(ethylene terephthalate) (PET), and the polyamides poly(caprolactame) (Nylon 6) and poly(hexamethylene adipamide) (Nylon 6,6) were fractionated and quantified through a sequence of selective solvent extractions followed by either analytical pyrolysis or reversed-phase HPLC analysis of the products of hydrolytic depolymerizations under acidic and alkaline conditions.

New methodologies for the detection, identification, and quantification of microplastics and their environmental degradation by-products.

Sampling, separation, detection, and characterization of microplastics (MPs) dispersed in natural water bodies and ecosystems is a challenging and critical issue for a better understanding of the hazards for the environment posed by such nearly ubiquitous and still largely unknown form of pollution. There is still the need for exhaustive, reliable, accurate, reasonably fast, and cost-efficient analytical protocols allowing the quantification not only of MPs but also of nanoplastics (NPs) and of the harmful molecular pollutants that may result from degrading plastics. Here a set of newly developed analytical protocols, integrated with specialized techniques such as pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS), for the accurate and selective determination of the polymers most commonly found as MPs polluting marine and freshwater sediments are presented.

Quantification of poly(ethylene terephthalate) micro- and nanoparticle contaminants in marine sediments and other environmental matrices.

Microplastics are ubiquitous pollutants in marine and freshwater bodies. Poly(ethylene terephthalate) microfibers (PMFs) are among the main primary microplastics (as-produced polymer microparticles). Released in large amounts in laundry wastewaters, PMFs end up in freshwater and marine sediments due to their high density.

New polymer-supported mono- and bis-Cinchona alkaloid derivatives: synthesis and use in asymmetric organocatalyzed reactions.

The straightforward synthesis of polystyrene-supported Chinchona alkaloids and their application in the asymmetric dimerization of ketenes is reported. Six different immobilized derivatives, consisting of three dimeric and two monomeric 9-O ethers, were prepared by "click" anchoring of soluble alkaloid precursors on to azidomethyl resins. The resulting insoluble polymer-bound (IPB) organocatalysts were employed for promoting the dimerization of in-situ generated ketenes.

Regulation of cardiac fatty acids metabolism in transgenic mice overexpressing bovine GH.

Cardiac energy metabolism depends mainly on fatty acid (FA) oxidation; however, regulation of FA metabolism in acromegalic (Acro) heart is unknown. The aim of the study was to evaluate cardiac expression of key proteins of FA metabolism in young and elder transgenic mice overexpressing bovine GH Acro. Expression of proteins regulating FA entry into the cells, their uptake by mitochondria and beta-oxidation were evaluated by western blot, while FA content by Fourier transform infrared microspectrometry.

Cardiac expression of adenine nucleotide translocase-1 in transgenic mice overexpressing bovine GH.

Heart hypertrophy is a common finding of acromegaly, a syndrome due to GH excess. Impairment of adenine nucleotide translocase-1 (ANT-1) gene, the main mitochondrial ADP/ATP exchanger, leads to cardiac hypertrophy. The aim of the study was to evaluate cardiac expression and the functional role of ANT-1 in 1- to 12-month-old transgenic mice overexpressing bovine GH (acromegalic mice, Acro) and littermate controls (wild-type mice, Wt).