A polymer concrete (PC) was synthesized by mixing styrenated polyester (SP) and marble wastes as fillers. The unsaturated polyester (UP) used was prepared from the reaction of oligomers obtained from the depolymerization of polyethylene terephthalate (PET) soft drink bottles with maleic anhydride and adipic acid. The UP was then mixed with the styrene monomers at a ratio of 60: 40% by weight to obtain the SP used for the synthesis of the PC. The aim of this work is to study the suitability of the prepared PC to be used as polymer based building materials. Using marble and PET soft drink bottle wastes for the preparation of the PC affects the environment positively, by avoiding the accumulation of these wastes. Saving the raw materials of polymer and fillers for other applications is another economical advantage of preparing the PC from the recycled PET and marble waste. Mechanical integrity of the PC was studied as blocks prepared under different experimental conditions. Chemical resistance and water absorption were also followed to evaluate the durability of the products obtained. In addition, the flammability of the SP and the PC prepared was also studied. Based on the data obtained, it could be concluded that the PC under consideration has good chemical resistance for 20% Na2CO3, 10% Noah, tap water, ground water and sea water. Besides the acceptable chemical resistance, the prepared PC shows low apparent porosity, low water absorption, and small open pores.

Two CO2 solid sorbents based on polyethylenimine, PEI (M(n) ∼ 423 and 10K), impregnated into mesoporous silica (MPS) foam prepared in kilogram quantities via a scale-up process were synthesized and systematically characterized by a range of analytical and surface techniques. The mesoporous silica sorbent impregnated with lower molecular weight PEI, PEI-423/MPS, showed higher capacity toward CO2 sorption than the sorbent functionalized with the higher molecular weight PEI (PEI-10K/MPS). On the other hand, PEI-10K/MPS exhibited higher thermal stability than PEI-423/MPS. The kinetics of CO2 adsorption on both PEI/MPS fitted well with a double-exponential model. According to this model CO2 adsorption can be divided into two steps: the first is fast and is attributed to CO2 adsorption on the sorbent surface; the second is slower and can be related to the diffusion of CO2 within and between the mesoporous particles. In contrast, the desorption process obeyed first-order kinetics with activation energies of 64.3 and 140.7 kJ mol(-1) for PEI-423/MPS and PEI-10K/MPS, respectively. These studies suggest that the selection of amine is critical as it affects not only sorbent capacity and stability but also the energy penalty associated with sorbent regeneration.

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ABSTRACT:The increasing demand for poly(ethylene terephthalate) (PET) polymer, the simultaneous shortage in landfill disposal spaces, and known problems associated with PET waste specifically (e.g., its nonbiodegradability and huge accumulation) are challenges with which mankind must cope nowadays. In this study, PET postconsumer bottle wastes were cut to very small slides and then subjected to an aminolysis process with ethanol amine as a degradative agent in the presence of one catalyst from three used in this study. These catalysts were dibutyl tin oxide, sodium acetate, and cetyltrimethyl ammonium bromide. The reaction was performed in sunlight: a beneficial, clean, cheap, and renewable source of energy. The end product, which was a white precipitate of bis(2-hydroxyethylene) terephthalamide, was subjected to spectrophotometric and thermal analyses. The product was characterized to asses its suitability for use in pigments in anticorrosive paint formulations. In general, this process was a green, environmentally friendly degradation based on the utilization of solar energy for the aminolysis reaction using simple, cheap, available chemicals as catalysts. The originality of this study was derived from the use of waste materials to yield a product with beneficial applications in the field of corrosion inhibition.

Sodium-montmorillonite (Mont-0) was partially/completely cation exchanged with appropriate amounts of cetyltrimethylammonium bromide to yield amphiphilic montmorillonites bearing different ratios of both hydrophilic and lipophilic segments. The lipophilicity/hydrophilicity range extended progressively up to the highly hydrophobic form (Mont-100), where all of the sodium cation content was replaced by the cetyltrimethylammonium cation. The produced amphiphilic forms can be arranged in the order of Mont-0 > Mont-25 > Mont-50 > Mont-75 > Mont-100, according to the decrease in hydrophilicity. Subsequently, the different montmorillonites were employed as reinforcing agents for acrylonitrile-butadiene rubber/styrene-butadiene rubber (50/50) rubber blend, which is known to be physically incompatible. We found from our previous reports that the mechanical properties of blends comprising a fixed loading of each montmorillonite form (20 phr) displayed remarkable improvements up to different levels indicating different compatibility influences between the rubber components by the inserted clays. In the current report, these results are intensively studied using dynamic mechanical thermal analysis and complemented by differential scanning calorimetry. Additionally, the network characteristics of the vulcanized rubber networks were determined for the neat blends (in absence of any clay) as well as for reinforced blends with different clay forms. Based on the obtained data, it could be concluded that the montmorillonite forms can bind both phases of the blend through interfacial interactions at the boundaries between the blend