Search results for " montmorillonite"

RGD-mimic polyamidoamine-montmorillonite composites with tunable stiffness as scaffolds for bone tissue-engineering applications

2017

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 t…

The Effects of Nanoclay on the Mechanical Properties, Carvacrol Release and Degradation of a PLA/PBAT Blend

2020

The formulation of polymeric films endowed with the abilities of controlled release of antimicrobials and biodegradability is the latest trend of food packaging. Biodegradable polymer (Bio-Flex&reg

Origin of clay minerals in soils on pyroclastic deposits in the island of Lipari (Italy)

2005

The island of Lipari (Italy) is characterized by calc-alkaline to potassic volcanism and a Mediterranean-type climate. The mineralogical and chemical features of two different soil profiles with ages of 92,000 and 10,000–40,000 y, respectively, have been investigated. There were no Andisols, but Vitric and Vertic Cambisols have developed at both sites. Although the morphology of the soils was similar, remarkable differences in the clay mineralogy between the two sites were observed. The site with the Vitric Cambisol was associated with the weathering sequence: glass → halloysite → kaolinite or interstratified kaolinite-2:1 clay minerals. Both sites had smectite in the clay fraction and, to …

“AD HOC” MODIFIED CLAYS FOR BIOTECHNOLOGICAL APPLICATIONS

Nowadays, the scientific community has to face with cogent problems strictly linked to the improvement of quality of live. Among the different tasks to achieve the prefixed objective the focus has been put on the drug administration, i.e., attention has been paid to propose an appropriate solution to improve the performance of a drug delivery system and to eliminate both the side effect and drawbacks. With the aim to achieve the design, synthesis, and characterization of versatile systems, with peculiar characteristics, based on clays and clays modified with a biocompatible surfactant, able to adsorb and release organic substances of pharmaceutical interest the present PhD thesis has been u…

Metal–Organic Frameworks (MOFs) Containing Adsorbents for Carbon Capture

2022

This research was funded by the European Regional Development Fund project “Innovation of the waste‐to‐energy concept for the low carbon economy: development of novel carbon capture technology for thermochemical processing of municipal solid waste (carbon capture and storage from waste—CCSW)”, grant number 1.1.1.1/19/A/013.

Simultaneous Removal and Recovery of Metal Ions and Dyes from Wastewater through Montmorillonite Clay Mineral

2019

The main objective of this work was to evaluate the potential of Montmorillonite nanoclay (Mt), readily and inexpensively available, for the simultaneous adsorption (and removal) of two classes of pollutants: metal ions and dyes. The attention was focused on two &ldquo

Neutral solar photo-Fenton degradation of 4-nitrophenol on iron-enriched hybrid montmorillonite-alginate beads (Fe-MABs)

2014

Hybrid montmorillonite-alginate beads (MABs) were prepared by the ion-gelation method from alginate and montmorillonite clay suspension dropped in a calcium chloride solution. Similarly, iron-enriched beads (Fe-MABs) were prepared using iron-exchanged montmorillonite. All beads were characterized by atomic absorption and Fourier-transform infrared spectroscopy. The efficiency of Fe-MABs as catalysts for the solar photo-Fenton performed at initial pH = 7.0 was evaluated by varying the catalyst amount and hydrogen peroxide concentration, and monitoring the removal of 4-nitrophenol (4-NP) at initial concentration of 10 ppm. A kinetic analysis showed that the removal of 4-NP by Fe-MABs followed…

The effect of montmorillonite clay in alginate gel beads for polychlorinated biphenyl adsorption: Isothermal and kinetic studies

2014

Beads of alginate montmorillonite have been used as sorbent for polychlorinated biphenyls from aqueous solutions.The structure and the differences between the different beads were established by IR spectroscopy (FT-IR). The adsorption at 25 °C has been studied in a batch system, following its kinetics and assessing adsorbent dose, initial PCB concentrations, and pH effects. The results show that increasing the initial concentration of the PCBs and the adsorption time favored the adsorption. Adsorption isotherm data were modeled using Chapman, Freundlich and Langmuir adsorption isotherms and the appropriate parameters were calculated.Adsorption of trichlorobiphenyls on alginate–montmorilloni…

Thermo-oxidative stabilization of poly(lactic acid)-based nanocomposites through the incorporation of clay with in-built antioxidant activity

2017

In this work, an innovative approach to overcome the issue of the poor thermo-oxidative stability of polymer/clay nanocomposites is proposed. Specifically, biodegradable poly(lactic acid) (PLA)-based nanocomposites, containing organo-modified clay with in-built antioxidant activity, were prepared. Through a two-step chemical protocol, a hindered phenol antioxidant was chemically linked to the ammonium quaternary salt which was then intercalated between the clay platelets [(AO)OM-Mt]. The nanocomposites were characterized and their thermo-oxidative stability during melt processing and under long-term thermal test conditions was investigated. PLA nanocomposites containing the (AO)OM-Mt showed…

Novel strategic approach for the thermo- and photo- oxidative stabilization of polyolefin/clay nanocomposites

2017

Polyolefin/clay nanocomposites were prepared by melt mixing and their oxidative stability was studied under long-term thermo- and photo-oxidative test conditions in the absence and presence of a modified organo montmorillonite clay (OM-MMt) containing a chemically-bound hindered phenol antioxidant function, (AO)OM-Mt. It was found that nanocomposites based on both polyethylene (PE) and polyethylene-grafted-maleic anhydride (PEgMA) containing the (AO)OM-Mt gave a higher oxidative stability, along with better clay dispersion, compared to analogous PE or PEgMA-based nanocomposites containing an added (free) conventional antioxidant with a similar hindered phenol function (using the commercial …