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Microplastics are increasingly pervasive pollutants, particularly abundant in the neuston where they drift with currents. We assessed dietary microplastic ingestion in the Mediterranean storm petrel (Hydrobates pelagicus melitensis), a small pelagic seabird that forages on plankton and inhabit the Mediterranean sea, one of the most polluted seas worldwide. We collected spontaneous regurgitates from 30 chick-rearing individuals and used GPS tracking data from 7 additional individuals to locate foraging areas. Birds foraged in pelagic areas characterized by water stirring and mixing, and regurgitates from 14 individuals (i.e. 45 %) contained microplastics. Fibers were the dominant shape (56 %), with polyester, polyethylene and nylon being the most frequent polymers. Our findings highlight the potential sensitivity of this species of conservation interest to plastic pollution and suggest that storm petrel regurgitates can be a valuable matrix to investigate microplastic ingestion in planktonic foragers, providing a characterization of spatio-temporal patterns of microplastic exposure in pelagic environments.

Since 30 years, liquid crystalline elastomers (LCEs) have been attracting the attention of many researchers thanks to their anisotropic molecular structure which allows them to build up artificial muscles. Possible applications span from soft robotics to biomedical or tunable optical devices. The power of thiol-yne click chemistry was recently demonstrated in the preparation of smart polymers, in particular LCEs, in which the mesogenic units are incorporated both in the main-chain and as pendant groups. To enrich the library of available LCE materials, in this work, several liquid crystalline dithiols and alkynes have been synthesized and copolymerized to obtain elastomers with different thermomechanical properties. The architecture of the main chain was found to play a prominent role in modulating the clearing point in a range of 60 °C, whereas only a minor contribution is given by the mesogens in the side chain. On the other hand, the mechanical response resulted highly sensitive to fine details of the side-chain structure. Accordingly, the present study not only improves the basic understanding of the chemical-physical properties of LCEs but paves the way to the preparation of multicomponent actuators able to deform in different temperature ranges, thus ultimately leading to complex soft robotic operations.

In the present study, a reliable and robust method was developed to quantify the molecular weight discrimination that can occur in grafting to reactions via indirect MALDI-TOF quantification of the molecular weights of grafted chains by comparing the characteristics of the polymeric material before the grafting reaction with those of the unreacted material recovered after grafting. Two polystyrene samples with different molecular weights and narrow molecular weight distributions were employed to prepare model blends that were grafted to silicon wafers and an analytical method was developed and validated to assess and quantify the modification of the molecular weight distribution that takes place during the grafting to process. Particular attention was paid to the standardization of the sample treatment and to find the best data collection and calibration methodologies in order to have statistically significant data even in the presence of a very scarce amount of the sample. Furthermore, to evaluate the accuracy of the analytical procedure, the lack of suitable standard and certified materials required a further experiment to be carried out by comparing the new optimized MALDI-TOF method and direct measurements using TGA-GC-MS on a model blend containing deuterated and hydrogenated polystyrene samples with appropriate molecular weights and distributions. The optimized method was applied on samples obtained by a thermally induced grafting to reaction from ultrathin polymer films and, for the first time, to our knowledge, an enrichment effect occurring in the ultrathin grafted layer obtained from a melt was evidenced.

Partly deuterated hydroxy-terminated poly(styrene d8-r-methyl methacrylate) statistical copolymers with different molecular weights were grafted to a silicon substrate. Then, fully hydrogenated hydroxy-terminated poly(styrene-r-methyl methacrylate) statistical copolymers were spun over the pregrafted substrate and let to react at 250 °C following the time evolution of the brush thickness and composition. Over time, the grafting density of the deuterated polymers decreases, whereas the grafting density of the hydrogenated polymers increases thus indicating the simultaneous occurrence of grafting and degrafting reactions. Moreover, keeping constant the grafting time, the total grafting density decreases as the molecular weight of the hydrogenated polymers increases, until a limiting value is reached when the molecular weight of the incoming polymer is equal to the one of the preformed brush. The overall picture of the experimental data, further supported by hybrid-particle field coarse-grained simulations, suggests that the reactivity of the system is related to the degree of stretching of the brush layer induced by the entering of additional polymer chains. This new vision of the grafting to mechanism implies that the self-limiting nature of this process derives from a mechanochemical control of the reaction rather than from diffusion/penetration effects.

The dewetting and ordering characteristics of a lamellae-forming poly(styrene-block-methyl methacrylate) block copolymer (BCP) either alone or blended with low-molecular-weight polystyrene and poly...

Previous research has reported avian plastic ingestion in marine bird species. Yet, while research attention on plastic pollution is shifting from marine to freshwater ecosystems, very few information on plastic ingestion is available for freshwater birds. Here, we examined the presence of microplastic in regurgitated pellets of the common kingfisher (Alcedo atthis) collected along the Ticino River (North Italy). In total, 133 kingfisher’s pellets were examined between March and October 2019 from 54 transects along the river. Plastic elements were detected and identified by visual inspection followed by μ-FTIR and SEM-EDS. Overall, we found 12 (micro)plastics from at least three different polymers in 7.5% of the pellets. This study provides the first report of plastic uptake of this bird species. It highlights the importance of spectroscopic techniques in plastic monitoring studies in order to avoid misidentification of items found. Documenting the presence of plastic ingestion by top carnivores such as fish-eating birds is necessary to understand the pervasiveness and impact of (micro)plastic pollution in food webs of freshwater ecosystems.

Copolymers of styrene (STY) and methylmetacrylate (MMA) are widely employed due to the low price of the starting monomers coupled with their synthetic versatility. A chromatographic method was developed for the simultaneous determination of the conversion degree of the single components of the polymer during the copolymerization reaction and the composition of the produced copolymer. The crude reaction mixture is directly analyzed during the reaction with only a dilution pretreatment. Accordingly, the method allows quick and simple monitoring of the reaction as it proceeds.

Microplastic (MP) contamination is ubiquitous and widespread in terrestrial and aquatic ecosystems, including remote areas. However, information on the presence and distribution of MPs in high-mountain ecosystems, including glaciers, is still limited. The present study aimed at investigating presence, spatial distribution, and patterns of contamination of MPs on three glaciers of the Ortles-Cevedale massif (Central Alps, Northern Italy) with different anthropic pressures, i.e., the Forni, Cedec and Ebenferner-Vedretta Piana glaciers. Samples of supraglacial debris were randomly collected from the glaciers and MPs were isolated. The mean amount (±SE) of MPs measured in debris from Forni, Cedec and Ebenferner-Vedretta Piana glaciers was 0.033 ± 0.007, 0.025 ± 0.009, and 0.265 ± 0.027 MPs g−1 dry weight, respectively. The level and pattern of MP contamination from the Ebenferner-Vedretta Piana glacier were significantly different from those of the other glaciers. No significant spatial gradient in MP distribution along the ablation areas of the glaciers was observed, suggesting that MPs do not accumulate toward the glacier snout. Our results confirmed that local contamination can represent a relevant source of MPs in glacier ecosystems experiencing high anthropic pressure, while long-range transport can be the main source on other glaciers.

A preferential grafting of short chains occurs during the “grafting to” reaction of hydroxy terminated P(S-st-MMA) blends consisting of short and long chains. The enrichment is enhanced when the chain length difference increases.

Complex deformities of lower limbs are frequent in children with genetic or metabolic skeletal disorders. Early correction is frequently required, but it is technically difficult and burdened by complications and recurrence. Herein, we described the case of a 7-year-old girl affected by severe bilateral genu varum due to spondyloepiphyseal dysplasia. The patient was treated by patient-specific osteotomies and customized structural wedge allograft using Virtual Surgical Planning (VSP) and 3D-printed patient-specific instrumentation (PSI). The entire process was performed through an in-hospital 3D-printing Point-of-Care (POC). VSP and 3D-printing applied to pediatric orthopedic surgery may allow personalization of corrective osteotomies and customization of structural allografts by using low-cost in-hospital POC. However, optimal and definitive alignment is rarely achieved in such severe deformities in growing skeleton through a single operation.

In the present study, a reliable and robust method was developed to quantify the molecular weight discrimination that can occur in

Magnetic materials in sample preparation for shotgun phosphoproteomics offer several advantages over conventional systems, as the enrichment can be achieved directly in solution, but they still suffer from some drawbacks, due to limited stability and selectivity, which is supposed to be affected by the hydrophilicity of the polymeric supports used for cation immobilization. The paper describes the development of an improved magnetic material with increased stability, thanks to a two-step covering of the magnetic core, for the enrichment of phosphopeptides in biological samples. Four materials were prepared featuring a polymeric shell with tunable hydrophilicity, obtained by “grafting from” polymerization of glycidyl methacrylate with 0–8.3% of polyethylene glycol methacrylate (PEGMA), the latter used to modulate the hydrophilicity of the material surface. Finally, the materials were functionalized with iminodiacetic acid for Ti4+ ion immobilization. The materials were analyzed for their composition by a combination of CHN elemental analysis and thermogravimetric analysis, also hyphenated to gas chromatography and mass spectrometric detection. Surface characteristics were evaluated by water contact angle measurements, scanning electron microscopy and energy dispersive X-ray spectrometry. These materials were applied to the enrichment of phosphopeptides from yeast protein digests. Peptides were identified by proteomics techniques using nano-high performance liquid chromatography coupled to mass spectrometry and bioinformatics. Qualitatively the peptides identified by the four systems were comparable, with 1606–1693 phosphopeptide identifications and a selectivity of 47–54% for all materials. The physico-chemical features of the identified peptides were also the same for the four materials. In particular, the grand average of hydropathy index values indicated that the enriched phosphopeptides were hydrophilic (ca. 90%), and only some co-enriched non-phosphorylated peptides were hydrophobic (21–28%), regardless of the material used for enrichment. Peptides had a pI ≤ 7, which indicated a well-known bias for acidic peptides binding, attributed to the interaction with the metal center itself. The results indicated that the enrichment of phosphopeptides and the co-enrichment of non-phosphorylated peptides is mainly driven by interactions with Ti4+ and does not depend on the amount of PEGMA chains in the polymer shell.

Polystyrene samples with different molar mass and narrow polydispersity index were prepared by nitroxide-mediated polymerization using N-tert-butyl-N-[1-diethylphosphono(2,2-dimethylpropyl)] nitrox...

Multiple osteochondromas (MO) is a rare disorder, characterized by benign osteocartilaginous tumors (osteochondromas), arising from the perichondrium of bones. The osteochondromas increase during growth, frequently causing deformities and limitations. Our study aims to analyze the data captured by the Registry of Multiple Osteochondromas, to refine Istituto Ortopedico Rizzoli (IOR) Classification, providing a representative picture of the phenotypic manifestations throughout the lifespan. We conducted a single-institution cross-sectional study. Patients were categorized according to IOR Classification, which identifies three patients' classes on the presence/absence of deformities and/or limitations. The present dataset was compared with our previously published data, to refine the classification. Nine hundred sixty-eight patients were included: 243 children (

Microplastics (MPs) are emerging contaminants in freshwater systems that have already attracted much scientific interest, but little attention has been paid to a multi-matrix analysis of MP occurrences along the length of a river. The present research provides the first record of MP contamination of four abiotic and biotic matrices from a river ecosystem simultaneously analysed. MPs were isolated and identified by micro-Fourier Transform Infrared (μ-FTIR) spectroscopy from samples collected along the Ticino River in North Italy during spring 2019. Abiotic samples were surface water (n = 18, 33 MPs m

Recent studies have documented the presence of microplastics (MPs) in remote areas, including soils or sediments collected in mountain and glacier environments, but information on their presence in snow is scant. The present study aimed at exploring the presence of MPs in residual snow collected in four locations of the Aosta Valley (Western Italian Alps), with different accessibility and human presence. Overall, the &micro, FTIR analyses confirmed the presence of 18 MPs in snow, 7 (39%) items were fibres, while 11 (61%) were fragments. Polyethylene (PE, 7 MPs) was the main polymer, followed by polyethylene terephthalate (PET, 3 MPs), high density PE (HDPE, 3 MPs), polyester (2 MPs), while only 1 MP made by low density PE, polypropylene and polyurethane were found. The mean (&plusmn, SE) concentration of MPs in snow ranged between 0.39 &plusmn, 0.39 MPs/L and 4.91 &plusmn, 2.48 MPs/L, with a mean of 2.32 &plusmn, 0.96 MPs/L for the sampling locations. The concentration of MPs did not statistically differ among locations. Our results suggest that MPs presence in high-mountain ecosystems might depend on deposition through atmospheric precipitations or local sources due to human activities. For these reasons, policies aiming at reducing plastic use and dispersal in mountain areas may be effective in preventing local MP contamination.

Summary: Development of biological tissues in vitro is not a trivial task and requires the correct maturation of the selected cell line. To this aim, many attempts were done mainly by mimicking the biological environment using micro/nanopatterned or stimulated scaffolds. However, the obtainment of functional tissues in vitro is still far from being achieved. In contrast with the standard methods, we here present an easy approach for the maturation of myotubes toward the reproduction of muscular tissue. By using liquid crystalline networks with different stiffness and molecular alignment, we demonstrate how the material itself can give favorable interactions with myoblasts helping a correct differentiation. Electrophysiological studies demonstrate that myotubes obtained on these polymers have more adult-like morphology and better functional features with respect to those cultured on standard supports. The study opens to a platform for the differentiation of other cell lines in a simple and scalable way.

Blends with different compositions of a partly deuterated hydroxy terminated poly(styrene d8-st-methyl methacrylate) copolymer with average molecular weight (Mn) of 11 200 g mol−1 and a hydroxy terminated poly(styrene-st-methyl methacrylate) copolymer with Mn = 5400 g mol−1 were grafted to a silicon wafer at temperatures ranging from 170 to 250 °C. A partition according to the molecular weight takes place during the “grafting to” reaction in which the lower molecular weight component is selectively incorporated into the polymeric brush. The time and temperature evolution of the layer composition for a specific blend composition as well as the effect of the blend composition on the final brush layer composition were systematically investigated. Hybrid particle-field simulations suggest that the propensity of short chains to preferentially react with the silicon surface comes from a combination of the average number of chains in contact with silica and the substrate surface area occupied by a single chain.

The study of CAD (computer aided design) modeling, design and manufacturing techniques has undergone a rapid growth over the past decades. In medicine, this development mainly concerned the dental and maxillofacial sectors. Significant progress has also been made in orthopedics with pre-operative CAD simulations, printing of bone models and production of patient-specific instruments. However, the traditional procedure that formulates the surgical plan based exclusively on two-dimensional images and interventions performed without the aid of specific instruments for the patient and is currently the most used surgical technique. The production of custom-made tools for the patient, in fact, is often expensive and its use is limited to a few hospitals. The purpose of this study is to show an innovative and cost-effective procedure aimed at prototyping a custom-made surgical guide for address the cubitus varus deformity on a pediatric patient. The cutting guides were obtained through an additive manufacturing process that starts from the 3D digital model of the patient’s bone and allows to design specific models using Creo Parametric. The result is a tool that adheres perfectly to the patient’s bone and guides the surgeon during the osteotomy procedure. The low cost of the methodology described makes it worth noticing by any health institution.

Monteggia fractures represent the association of a fracture of the proximal ulna and luxation of the radial head. This type of lesion is infrequent and may be misdiagnosed, particularly in paediatric patients. Classification of these injuries is based on the scheme proposed by Bado and later supplemented by other authors to better discriminate doubts and to guide the treatment. The treatment of choice of acute Monteggia lesions in the paediatric age is in most cases conservative, and it involves reduction and immobilisation in a cast. Surgery is mostly reserved for complex cases and for inveterate lesions that represent a high risk for chronic disorders and disabling sequelae; in these cases, the choice of treatment remains controversial. The aim of this article is to describe the anatomical-pathological characteristics, the diagnostic criteria, and the principles of treatment of Monteggia lesions in the paediatric age.

An hyphenated method based on thermal gravimetric, gas chromatographic and mass spectrometric analyses (TGA-GC–MS) is proposed for the quantitative analysis of diethylphosphate-end capped polymers with varying chain length, in bulk and as ultra thin film. The method fully calibrated and validated, revealed a powerful and affordable tool in the determination of the amount of phosphorous in polymeric samples but also it allows the determination of the number of repeating units per chain end. Compared to the common techniques, namely NMR spectroscopy and ICP-MS, no sample pretreatments are required. Consequently, polymeric films supported on inert substrates can be directly analyzed. The quantitative calibration, obtained for bulk materials, was demonstrated to be accurate also for films of different thickness. In this frame, the method revealed highly sensitive thus allowing the phosphorous determination even in ultrathin films with thickness of few tens of nanometers. Finally, the chromatographic profile of the species evolving during the thermal degradation was found to depend on the polymeric film thickness. This implies that information concerning the polymer stability and degradation mechanism at different size scale can be obtained. Considering the widespread interest for thin and ultrathin films of polymers containing phosphorous groups for brush-based technologies, the proposed method can be helpful in various areas, including flame retardant material, healthcare and medicine, microelectronic, for facile and precise characterization of functional interfaces.

Importance Multiple osteochondromas is a rare hereditary skeletal disorder, characterized by bony protrusions arising from growth plates on long bones during skeletal development. The disorder frequently leads to diminished stature, deformities and functional limitations. Understanding of the natural history of multiple osteochondromas and its evolution in children and adolescents is limited. Objective To provide valuable information on the natural history of multiple osteochondromas, to inform recommendations for treatment and prevent impairments caused by osteochondromas. Design This retrospective cohort study in children with multiple osteochondromas includes longitudinal data collected from first to last follow-up visit for patient demographics, and over 36 months for disease evolution. Setting Data were collected from the Registry of Multiple Osteochondromas, which includes data from circa 1200 patients with multiple osteochondromas treated from 2003 to 2017 at IRCCS Istituto Ortopedico Rizzoli in Bologna. Participants Patients ≤18 years with multiple osteochondromas, who provided written informed consent and had data for ≥1 12-month follow-up visit. Main outcome(s) and measurement(s) Demographics, clinical features, incidence of surgeries, and disease evolution (progression or regression) were assessed. Results were summarized using descriptive statistics, annual rates of new clinical features and surgeries, and Kaplan-Meier estimates. Patient height was evaluated following Italian growth charts. Results 158 patients were included in these analyses. Throughout follow-up, 80.4% of patients developed new osteochondromas, 57.6% developed new deformities, 23.4% developed new functional limitation(s). New osteochondroma(s) were developed by 28.5% patients by Month 12, 39.9% at Month 24, 50% at Month 36. Most new osteochondromas were detected in the younger population; patients aged 0–4 years underwent a significantly higher number of lesions within 12, 24 and 36 months of follow-up. The overall incidence of patients with ≥1 new deformity within 12 months was 17.7%, with incidences decreasing with increasing age (p = .023). In addition, the analyses on height highlight that 13 years is a cut off age for slow growth of the stature (p Conclusions and relevance This natural history study reports the main set of clinically relevant data for patients with multiple osteochondromas during skeletal development, providing insight for patient management and development of therapeutic interventions.

This paper deal with the synthesis and characterization of a new class of magnetic molecularly imprinted (MIP) particles, with selective recognition properties for Zearalenone (ZEN), an estrogenic mycotoxin. These particles present a multishell structure, comprising a magnetic core, constituted by spherical aggregates of magnetite nanoparticles (Fe3O4 nanoparticles), covered by a thin silica layer and surrounded by a molecularly imprinted (MIP) polymer shell, obtained employing quercetin as the dummy template and 4-vinylpyridine as the functional monomer. A multistep synthetic procedure was developed leading to spherical particles with a mean diameter of approximately 900 nm and a high magnetic fraction. The MIP were tested for ZEN re-binding properties. ZEN-MIP material had 55-fold more affinity for ZEN than the corresponding non-imprinted (NIP) material, that highlighting their potential for ZEN concentration from complex food matrices.

The ability to obtain 3D polymeric objects by a 2D-to-3D shape-shifting method is very appealing for polymer integration with different materials, from metals in electronic devices to cells in biological studies. Such functional reshaping can be achieved through self-folding driven by a strain pattern designed into the molecular network. Among polymeric materials, liquid crystalline networks (LCNs) present an anisotropic molecular structure that can be exploited to tailor internal strain, resulting in a natural non-planar geometry when prepared in the form of flat films. In this article, we analyze the influence of different molecular parameters of the monomers on the spontaneous shape of the polymeric films and their deformation under different stimuli, such as heating or light irradiation. Modifying the alkilic chains of the crosslinkers is a simple and highly effective way to increase the temperature sensitivity of the final actuator, while modifying ester orientation on the aromatic core interestingly acts on the bending direction. Combining such effects, we have demonstrated that LCN stripes made of different monomeric mixtures originate complex non-symmetric deformation under light activation, thus opening up new applications in photonic and robotics.

Block copolymers (BCPs) are emerging as a cost-effective nanofabrication tool to complement conventional optical lithography because they self-assemble in highly ordered polymeric templates with well-defined sub-20-nm periodic features. In this context, cylinder-forming polystyrene-block-poly(methyl methacrylate) BCPs are revealed as an interesting material of choice because the orientation of the nanostructures with respect to the underlying substrate can be effectively controlled by a poly(styrene-random-methyl methacrylate) random copolymer (RCP) brush layer grafted to the substrate prior to BCP deposition. In this work, we investigate the self-assembly process and lateral order evolution in RCP + BCP systems consisting of cylinder-forming PS-b-PMMA (67 kg mol–1, PS fraction of ∼70%) films with thicknesses of 30, 70, 100, and 130 nm deposited on RCP brush layers having thicknesses ranging from 2 to 20 nm. The self-assembly process is promoted by a rapid thermal processing machine operating at 250 °C fo...

Functional hydroxyl-terminated poly(styrene-r-methyl methacrylate) (P(S-r-MMA)) copolymers (RCPs) are becoming key materials to control the substrate wetting characteristics not only for the conventional polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) block copolymers (BCPs) but also for high χ BCP systems. This paper reports the thermal stability of RCPs at fixed composition as a function of molar mass and at fixed molar mass as a function of composition. Distinct and sometimes opposite dependencies were observed when the samples were analyzed in bulk, in the form of thermally untreated thin films featuring different thicknesses and in the form of brush layers after the grafting process performed at different temperatures. The overall picture of these effects is useful for optimizing the thermal processing conditions of the various steps involved in BCP-based pattern transfer technology.

Light responsive liquid crystalline networks were prepared by photopolymerization of azobenzene-doped mesogen mixtures and applied for production of micro-actuators by a laser writing technique. Adjusting the cross-linker content was found to be an efficient and easy way to control the dynamics of light-induced deformation from the micro- up to the macro-meter length scales. Starting from a complete characterization of the response of millimeter-sized stripes under irradiation with different sources (LED and laser light), micro-structures based on different monomer mixtures were analyzed for micro-actuator preparation. Double stripes, able to perform a light driven asymmetric movement due to the different mixture properties, were created by a double step process through a laser writing system. These results are a simple demonstration of an optically activated non-reciprocal movement in the microscale by a chemical material manipulation. Moreover, we demonstrate a rapid actuator dynamics that allows a movement in the second time scale for macrostructures and a millisecond actuation in the microscale.

Hydroxyl terminated poly(styrene-r-methyl methacrylate) (P(S-r-MMA)) random copolymers (RCPs), with molecular weight (Mn) spanning from 1700 to 69 000 g mol−1 and equal styrene unit content, were grafted at different temperatures onto a silicon oxide surface and subsequently used to study the orientation of nanodomains with respect to the substrate, in cylinder forming polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) block copolymer thin films. When the grafting temperature increases from 250 to 310 °C, a substantial increase in the grafting rate is observed. In addition, an increase in the surface neutralization efficiency occurs thus resulting in an increase in the robustness of the surface neutralization step. These data revealed that the neutralization of the substrate is the result of a complex interplay between RCP film characteristics and underlying substrate properties that can be finely tuned by properly adjusting the temperature of the grafting process. © 2016 Society of Chemical Industry

The self-assembly of block copolymer (BCP) thin films produces dense and ordered nanostructures. Their exploitation as templates for nanolithography requires the capability to control the lateral order of the nanodomains. Among a multiplicity of polymers, the widely studied all-organic polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) BCP can easily form nanodomains perpendicularly oriented with respect to the substrate, since the weakly unbalanced surface interactions are effectively neutralized by grafting to the substrate an appropriate poly(styrene-random-methyl methacrylate) P(S-r-MMA) random copolymer (RCP). This benefit along with the selective etching of the PMMA component and the chemical similarity with the standard photoresist materials deserved for PS-b-PMMA the role of BCP of choice for the technological implementation in nanolithography. This work demonstrates that the synergic effect of thermal annealing with the initial solvent naturally trapped in the basic RCP + BCP system after the deposition process can be exploited to enhance the lateral order. The solvent content embedded in the total RCP + BCP system can be tuned by changing the molecular weight and thus the thickness of the grafted RCP brush layer, without introducing external reservoirs or dedicated setup and/or systems. The appropriate supply of solvent supports a grain coarsening kinetics following a power law with a 1/3 growth exponent for standing hexagonally ordered cylinders.

This paper reports on the development of montmorillonite (MMT)-reinforced hydrogels, based on a peptidomimetic polyamidoamine carrying guanidine pendants (AGMA1), as substrates for the osteo-induction of osteoblast precursor cells. AGMA1 hydrogels of various degrees of crosslinking responded favourably to MMT reinforcement, giving rise to composite hydrogels with shear storage modulus G', when fully swollen in water, up to 200 kPa, i.e. 20 times higher than the virgin hydrogels and of the same order or higher than other hydrogel-based composites proposed for orthopaedic applications. This significant improvement was ascribed to the effective interpenetration between the polymer matrix and the inorganic filler. AGMA1-MMT hydrogels, when evaluated as scaffolds for the osteogenic differentiation of mouse calvaria-derived pre-osteoblastic MC3T3-E1 cells, proved able to support cell adhesion and proliferation and clearly induced differentiation towards the osteoblastic phenotype, as indicated by different markers. In addition, AGMA1-MMT hydrogels proved completely degradable in aqueous media at pH 7.4 and did not provide any evidence of cytotoxicity. The experimental evidence suggests that AGMA1-MMT composites definitely warrant potential as scaffolds for osteoblast culture and bone grafts. Copyright © 2016 John Wiley & Sons, Ltd.

A graphene-containing LDH was prepared by re-hydration of the oxides produced by the calcination of an organic LDH. While the memory effect is a widely recognized effect on oxides produced by inorganic LDHs, it is unprecedented from the calcination/re-hydration of organic ones. Different temperatures (400, 600 and 1100 °C) were tested, on the basis of thermogravimetric data. Water instead of a carbonate solution was used for the re-hydration, with CO2 available from water itself and/or air to induce a slower process with an easier and better intercalation of the carbonaceous species within the layers. The samples were characterized by X-ray Powder Diffraction (XRPD), IR and Raman spectroscopy and scanning electron microscopy (SEM). XRPD indicate the presence of carbonate LDH mixed with a layered phase with a larger d-spacing. IR confirmed that the prevailing anion is carbonate, coming from the water used for the re-hydration and/or air. Raman data indicated the presence of low-ordered graphenic species moieties and SEM the absence of separated graphene of graphitic sheets, suggesting an intimate mixing of the carbonaceous phase with reconstructed LDH. Organic LDHs gave better memory effect after calcination at 400 °C. Conversely, the graphenic species are observed after rehydration of the sample calcined at 600 °C with a reduced memory effect, demonstrating the interference of the carbonaceous phase with LDH reconstruction and the bonding with LDH layers to form a graphene-LDH nanocomposite.

Boron-terminated polystyrene with molecular weight ranging from 1800 to 18000 g/mol were synthesized for p-type doping of silicon substrates through spin-on technique. Several polymers were prepared using the ARGET-ATRP method using tert-butyl 2-bromoisobutyrate as initiator, changing monomer to initiator ratio and the reaction time. After polymerization, polystyrene samples were functionalized in order to end-cap the chains with a boron-containing molecule. Various polymers were characterized by SEC, to estimate Mn, Mw and PDI, by NMR (1H and 13C) in order to investigate the correct structure of the molecules and by TGA-GC-MS for knowing the thermal behavior and the amount of boron into the polymers.

The aim of this work is to obtain block copolymer brushes by a combined grafting to and grafting from approach. A new strategy was employed in which the second block re-growths starting from a homopolymer brush layer obtained by the grafting to approach. In detail, polystyrene samples with molecular weight ranging from 2.5 to 13 kg/mol and narrow molar mass distribution were synthesized by nitroxide-mediated-polymerization (NMP) using N-tert-butyl-N-[1-diethylphosphono(2,2-dimetylpropyl)] nitroxide (SG1/DEPN) as polymerization controller. Such polymers were grafted onto a silicon oxide surface by Rapid Thermal Processing (RTP) at different temperatures. As thermolabile groups deriving from the terminal SG1 are located at the silica surface, they could allow a synthesis of block copolymers via the grafting from approach by surface initiated NMP. Preliminary experiments of regrowth from surface were conducted with deuterated styrene and 4-vinylpyridine. The corresponding block copolymer brushes were obtained and their characteristics discussed as a function of the relevant reaction parameter.