The purpose of the present work was to prepare polypropylene (PP) matrix composited filled with chemically treated pistachio shell particles (PTx), and evaluate their effect on the composites’ thermal properties. PP-PTx composites were formulated in different PTx content (from 2 to 10 phr) in a mixing chamber, using the melt-mixing process. The PTx were chemically treated using a NaOH solution and infrared spectroscopy (FTIR). According to thermogravimetric analysis (TGA), the treatment of pistachio shell particles resulted in the remotion of lignin and hemicellulose. The thermal stability was evaluated by means of TGA, where the presence of PTx in composites showed a positive effect compared with PP pristine. Thermal properties such as crystallization temperature (Tc), crystallization enthalpy (∆Hc), melting temperature (Tm) and crystallinity were determinate by means differential scanning calorimetry (DSC); these results suggest that the PTx had a nucleation effect on the PP matrix, increasing their crystallinity. Dynamic mechanical analysis (DMA) showed that stiffness of the composites increase compared with that PP pristine, as well as the storage modulus, and the best results were found at a PTx concentration of 4 phr. At higher concentrations, the positive effect decreased; however, they were better than the reference PP.

The effect of sargassum particle size on the final properties of sargassum-modified asphalt is investigated in this article. Seaweed sargassum particles were first obtained and characterized through elemental analysis, thermogravimetric analysis (TGA), X-ray diffraction, and FTIR spectroscopy. Additionally, pure and sargassum-modified asphalt blends were evaluated through physical and rheological tests such as penetration, softening point, thermal stability, dynamic viscosity, failure temperature, and epifluorescence microscopy. Modified asphalt blends were prepared by the hot mixing technique using different proportions of sargassum particles of two maximum sizes: 500 μm and 850 μm. Incorporating 3.0 wt.% of sargassum particles under 500 μm into the asphalt increased the viscosity of the original binder by a factor of 2.5 and its complex modulus by a factor of 1.9. At the same time, its failure temperature was 11 °C higher than the reference asphalt, which implies an improved viscoelastic behavior and rutting resistance at high temperatures. The study results suggest that the particles under 500 μm were responsible for the most significant effect on the final properties of the asphalt. Moreover, the storage stability test revealed that the modified asphalt blends are stable when the sargassum particle content was kept below 3.0 wt.%. The statistical analysis of the effect of sargassum particle size and concentration on the modified asphalt properties revealed that the rheological behavior is more affected by the modifier particle size; in contrast, the conventional physical properties were more determined by its concentration. Therefore, using low proportions of fine sargassum particles is efficient for improving the physical and rheological properties of the original asphalt, which is not only positive from the asphalt modification technology point of view but also from a sustainable perspective, since seaweed sargassum has become a useless plague in many coastal regions.

The use of plant waste, such ashusks, fibers, and bagasse, as additives in polymeric matrices generated great interest recently, since they became an option to be used as additives, reinforcers, or only as fillers. The pistachio is a seed for human consumption, while the Jatropha curcas (JC) is a seed from which oils are extracted, and are used to obtain biofuels; however, their shells are not used when discardedbecause no useful application is known.An interesting application for this waste material is to use it as a bioadditive in polymeric matrix. The objective of the present work is to prepare polymer composites with polypropylene (PP) as a matrix and as a bio-additive particle inseed shells, in this case Jatropha curcas shell particles (JA) and pistachio shell particles (PI), in different content from 2 to 10 phr. The composites were characterized by techniques such as differential scanning calorimetry (DSC) and X-ray diffraction (XRD) to evaluate crystallinity; by using thermogravimetric analysis (TGA), the thermal stability was studied, and by using dynamic mechanical analysis (DMA) the viscoelastic behavior of composites was evaluated. According to DSC, results suggest that a nucleating effect occurs with the addition of the JA and PI, which was reflected in an increase in thepercent of crystallinity of the composites. The TGA results show that thermal stability of the composites was modified with the presence of JA and PI, compared with that PP pristine.In addition, dynamic mechanical analysis (DMA) reported that the viscoelastic behavior was modified, findinga higher capacity to dissipate energy for composites, PI being the one that presented a greater effect on them.

In the present work, the evaluation of chicken feather particles (CFP) and styrene-butadiene/chicken feather (SBS-CF) composites as modifiers for asphalt binder is presented. It is well known that elastomers are the best asphalt modifiers, because their thermoplastic behavior assists asphalts in improving the range of their mechanical properties at both low and high temperatures. Nowadays, the use of natural products and byproducts as fillers for polymer matrices has been a matter of research, and the field of asphalt modification is not the exception. Chicken feather particles (CFP) is a waste material whose main component is keratin, which offers remarkable properties. In the present work, CFP was used as a filler of a styrene-butadiene rubber matrix (SBS) with radial structure, to obtain a composite intended as an asphalt modifier. Besides, raw CFP was also tested as an asphalt modifier. Physical, thermal and rheological properties of the modified asphalts were evaluated in order to determine their degree of modification with respect to the original asphalt. The results show that the addition of raw CFP improves some physical properties as penetration and decreases the phase separation; furthermore, the asphalt modified with CFP displayed similar rheological properties to those shown by the asphalt modified with SBS, while some other properties resulted in being even better, like the phase separation, with the advantage that the CFP comes from a natural waste product.

The present work evaluates the influence of different properties of composite materials from natural sources. Films were prepared using the evaporative casting technique from corn starch reinforced with a waste material such as garlic husk (GH), using glycerin as a plasticizer. The results of the syntheses carried out demonstrated the synergy between these materials. In the morphological analysis, the compatibility and adequate dispersion of the reinforcer in the matrix were confirmed. Using Fourier transform infrared spectroscopy (FTIR), the interaction and formation of bonds between the matrix and the reinforcer were confirmed by the presence of some signals such as S-S and C-S. Similarly, thermogravimetric analysis (TGA) revealed that even at low concentrations, GH can slightly increase the decomposition temperature. Finally, from the results of dynamic mechanical analysis (DMA), it was possible to identify that the storage modulus increases significantly, up to 115%, compared to pure starch, especially at low concentrations of the reinforcer.

Sargassum is a type of marine algae that has caused environmental problems in Mexico because it arrives in high quantities along the Mexican coast, especially in the Mexican Caribbean. This situation has become an environmental and economic problem, impacting tourism and other activities. As a result, it is reasonable to try to find an application for these algae. Recently, some applications in civil construction, cosmetics, and the food industry, among others, have been reported. The present work evaluates the thermal and structural properties of new polypropylene (PP)–Sargassum-based composites. Also, the effect of adding calcium stearate (CS) to increase the interaction between PP and Sargassum particles was investigated. PP–Sargassum particle composites were prepared by a melt mixing process, and the properties of these composites were evaluated using thermal techniques such as dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and infrared spectroscopy (FTIR). The DMA results showed that composites with low concentrations of Sargassum particles perform better than those with higher concentrations. When CS was added to composites, there was a significant improvement in storage modulus compared with composites without CS. This was attributed to the good adhesion of the particles to the matrix because the mobility of macromolecules increased in the presence of CS. The thermal stability of PP–Sargassum particle composites decreases when the amount of particles increases, and the addition of CS does not positively affect the thermal behavior of composites. The findings open the possibility of using Sargassum particles in new applications of these algae as a polymer additive to generate sustainable materials.