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In the present study, the superplasticizing effect of HASE (Hydrophobic Alkali Swellable Emulsions) associative polymers on a cementitious formulation has been studied through a Design of Experiment (DoE) statistical approach. The main advantage of a study based on a DoE approach is that it gives the possibility of carrying out tests in which there is a combination of the parameters chosen on two extremes. Thus, the tests are driven by a combination of these parameters according to the design.The DoE approach was used to optimize the combination of HASE polymer synthesis reaction variables. As a final response from the design, or rather as an objective of our synthesis, the superplasticizing effect that each polymer has on the final diameter variation of the cementitious formulation after the Flow Table Test was chosen. The variation of the final diameter was considered as the difference with respect to the same formulation without the addition of the superplasticizer.The variables were chosen in such a way as to have the greatest impact on the reaction product, in particular the quantity of acidic methacrylic monomer (MMA), quantity of surfactant (SDS), quantity of free radical initiator (ASP) and reaction time (t). These variables were assumed to be independent variables. The design also included a central level, that is an experiment in which all the factors are set at an intermediate value between the minimum and the maximum. In this case, only one central level was added for a total of 17 experiments. By applying the DoE design it was possible to identify that the variable that has the greatest influence on the final response, that is the diameter of the cementitious formulation after the Flow Table Test, is the variable linked to the concentration of the initiator (ASP). The other variables showed a lesser influence on the final response.

This manuscript presents data related to the research article entitled “Synthesis and characterization of sustainable polyurethane foams based on polyhydroxyls with different terminal groups” (DOI: 10.1016/j.polymer.2018.06.077) [1]. We provide Supplementary data on the chemical properties, in terms of FTIR characterization, of polyhydroxyls produced starting from bio-based feedstock (biosuccinic acid and 1,4 butandiol) and thermal properties (glass transition temperature-Tg and thermal degradation behavior) of polyurethane and copolymer urethane-amide foams manufactured from the aforementioned polyhydroxyls. The FTIR characterization elucidates the chemical structure of polyhydroxyls and allows to make some hypothesis on their reaction routes with the isocyanate molecules. The thermal characterization revealed that the addition of bio-based polyhydroxyls to the sample formulations improves both the glass transition and degradation temperature of the foams. These foamed products exhibit potential performances to be applied as a substitute for conventional polyurethane foams.

The epoxidation of soybean oil is industrially carried out by using peroxyacid generated in situ by reacting concentrated hydrogen peroxide with acetic or formic acid, in the presence of a mineral acid as a catalyst. The reaction is generally highly exothermic and an excessive increase of temperature is proved to occur, with clear safety issue. This unwanted phenomena is typically prevented by limiting the peroxyacid reactant amount with respect to the stoichiometry, either in semi-continuous fed-batch or in pulse-fed-batch. In this paper, starting from experiments and given kinetic data, the set of reactions have been analysed in the light of safety, by means of classical runaway criteria.

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The production of biodiesel as a fuel in diesel engines greatly increased in recent years and is expected to grow more and more in the near future. Increasing biodiesel consumption requires optimized production processes allowing high production capacities, simplified operations, high yields, and the use of more economic feedstocks such as waste oils and fats. However, the latter often contain large amounts of free fatty acids and cannot be processed with the commonly practiced technology based on the use of alkaline catalysts in the homogeneous phase that requires the use of highly refined oil as raw materials. Therefore, the development of processes for low-cost biodiesel production requires the individuation of heterogeneous catalysts that are very efficient in promoting the transesterification reaction also in the presence of free fatty acids and water, allowing the prompt separation of pure glycerol and not requiring expensive purification of this byproduct. In the present contribution, the performances of different heterogeneous catalysts are compared both in the absence and in the presence of free fatty acids. In some cases, the resistance of the catalysts to the presence of water and the eventual deactivating effects after the first use have also been tested. The catalysts considered are both basic and acidic in nature, such as hydrotalcite, MgO, TiO2grafted on silica, vanadyl phosphate, and different metals-substituted vanadyl phosphate of the type Me(H2O)xVO1-xPO4·2H2O, where Me is a trivalent cation such as Al, Ga, Fe, and Cr and where x0.18−0.20. Finally, the understanding of the kinetic behavior of the most stable catalyst TiO2/SiO2has been deepened. [ABSTRACT FROM AUTHOR]