Intercalation of acrylamide into interlayer spaces of natural montmorillonite called maghnite (Algerian MMT) by the free solvent polymerization technique under microwave irradiation was studied. The transformation was carried out with using both the raw (maghnite-Na fin) and treated clay (maghnite-Na+ fin) in aqueous sodium hydroxide NaOH solution (1 M). It was shown that no initial modification of the layered mineral (by ion-exchange with Na+ cations or organophilization) is needed for the successful introduction of anionic hydrogels into the interlayer gallery. The goal of the present study was to synthesis anionic polyacrylamide/maghnite composite with similar composition and structure to that synthesized of other catalyst. Maghnite catalyst has a significant role in the industrial scale. In fact, the use of maghnite is preferred for its many advantages: a very low purchase price compared to other catalysts, the easy removal of the reaction mixture. The anionic sodium-clay polyacrylamide material exhibited a tendency to the formation of exfoliated structure. The synthesized hydrogels, as monitored by the swelling behavior were characterized by Fourier transform infrared and 1HNMR analysis.
Part of the book: Characterizations of Some Composite Materials
Polyaniline (PANI) and its block copolymer (PANI-PEO2000) has been prepared under effect of Maghnite-H+ (Algerian MMT) in different weight percentage (wt %) by cationic polymerization method. The structure of PANI and PANI-PEO2000 is predicted by the FT-IR and 1HNMR spectra. The thermal stability of homopolymer and block copolymer is confirmed by difference scanning calorimetry and analysis thermogravimetry. So after this results we can suggest that our heterogeneous catalyst called maghnite (Algerian MMT) can modified the morphology and the physical chemical properties of polyaniline (PANI) and its homolog block polyaniline-b-poly ethylene oxide (PANI-b-PEO2000) in the mild conditions under microwave irradiation.
Part of the book: Composite Materials
In this chapter, we present our study of geopolymers and hybrid geopolymers synthesized with treated fly ash from eggshells (FAES) and sand from the dunes of southern Algeria using activators such as NaOH and Na2SiO3, respectively, in addition to the organic polymer polyethylene terephthalate (PET). Several parameters have been modified, such as alkali concentration and percentage of activators and PET, with the objective to improve the quality of the desired geopolymers and hybrid geopolymers. The main objective of this work is to study the use of waste PET in the matrix of this new material to replace Portland cement, which is widely used today, as well as develop ecological building materials that are durable and lightweight and prevent chemicals from attacking old structures. Through optical and electron microscopy, we studied the effect of the addition of PET on the structure of our geopolymer material and on the bond and interface areas between the aggregates and the matrix. The microstructural analysis discussed here refers to specimens containing 5% PET by weight. We observed that PET contents significantly altered the structure and morphology of the samples.
Part of the book: Sustainability of Concrete With Synthetic and Recycled Aggregates
The wetland of Naâma situated in the arid region of Alegria offers an important fauna and flora diversity due to its geographical location it constitutes the main resting place in North Africa for migratory birds. Insects are used as bioindicators, due to their sensitivity to environmental conditions which, because of their ecological peculiarities, gives information on the characteristics of terrestrial and aquatic environments. The aim of this study is to know and specify the entomofauna bio-indicator of the quality of the aquatic environment of the wetland Naâma (SW Algeria). The study carried out in the wetland from September 2017 to September 2020. Benthic insects were sampled according to the IBGN protocol (Standard Global Biological Index). Study and statistical analysis of insects communities was based by the use of the structural and statistical index, Correspondence factor analysis (CFA), and The ascending hierarchical classification (C.H.A). The results show that the collected insect 51 species, belong to 9 orders, The Coleoptera order is the most represented with 11 species, followed by the Odonata with six species, Lepidoptera ranks third with five species followed by Diptera with 03 species. The various indicators used, namely the specific richness (51 species), the Shannon index (1.01 bits), and fairness (0.56) show that this environment is characterized by significant fauna biodiversity. The study of the hydro-biological quality of the water courses of this site, assessed by the IBGN method showed a good hydro-biological quality with moderate pollution (IBGN = 14). This pollution is precisely marked by the requirement of Ephemeroptera and the disappearance of Plecoptera. These results lay the foundation for any biomonitoring action of the ecological quality of the waters of this wetland.
Part of the book: Vegetation Index and Dynamics