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Hybrid laminate composites based on two natural long fiber combinations as jute/coir and jute/doum fibers at different layers stacking were successfully manufactured by using illite clay particles at various content (5−20 wt%). Mechanical and rheological tests were conducted on the elaborated composite in real-time and after aging in order to investigate the effects of clay incorporation, natural fiber hybridization, and long-term aging on mechanical, physical, and morphological properties. The properties of the laminate composites were mainly influenced by the use of hybrid matrices at different clay content and hybrid fibrous reinforcement (jute/coir and jute/doum), fiber orientations ([0] and [45]), and fiber architecture (canvas and matt). The mechanical properties of realized hybrid laminate composites increased with the addition of clay up to an optimum value at 15 wt%. The complex modulus G* confirms that the laminates have an elastic behavior. The long-term aging of laminates has also been investigated by choosing 5 years as long-term duration. This choice, not random, represents moderately the period of maturity of the functional composite parts used in different industrial sectors. The results of aged laminates show an abyssal decrease of rigidity (54%), tensile strength (20%) and complex modulus (97%) and a highly considerable increase of strain at yield up to 54%. This decrease is mainly attributed to the relaxation phenomenon of polymeric chains of epoxy and deterioration of natural fibres.

This study aims to develop a new low carbon composite material using illite clay and titanium dioxide as a stabilizing and whitening agent. It investigates the effect of the inclusion of titanium dioxide nano-powder and illite particles on optical, thermal, and mechanical performances of polypropylene (PP) matrix. The composite samples based on binary (PP-illite) and ternary (PP-illite-titania) composites at various particle contents of illite-titania have been manufactured by using a melt-compounding technique. The results showed that the low loading of titania has a significant effect on the whiteness index of the composites. The comparative analysis also demonstrated that the thermal stability was increased by approximately 7% in the case of the composites reinforced by the illite-titania at 18:2 wt%. Moreover, the addition of titania powder leads to ensure stabilization of tensile strength properties for all composites and also allowing Young’s modulus to gain increase of 83% for the composites reinforced by 2 wt% of titania powder. As for the addition of titanium dioxide until 5 wt%, an improvement in the aesthetic appearance of the composites is well noted by slightly decreasing the other specific properties. By combining the useful with the pleasant, and from different results obtained, it is proposed to use an optimal percentage of titania is less than 2% without impacting the hygroscopic and resistance of ternary composites and enhancing the rigidity of polymer products.

The focus of this work was the possibility to expand the use of coir fibers, as byproduct of the coconut industry by turning them into new eco-composites. The evaluation of coir fiber-reinforced composites focuses on the chemical treatment and processability of the coir fiber, how well it interfaces with a phenolic resin as Bakelite, and an analysis of how the mechanical properties of the final product change when adding treated coir fibers. The results show that the flexural stress value of composite shows a stabilization and the ductile behavior of composites was improved around 34.45% as compared to the neat Bakelite matrix. However, dynamic mechanical analysis showed a change in the rheological properties of the biocomposites with increasing temperature and fiber loading; the increase of temperature tends to enhance the free volume of the system and thereby decreases the fibers-matrix adhesion surface leading to decrease the complex modulus. This study represents a new opportunity to valorize biomass residues into green materials, which could reduce domestic dependence on petroleum-based thermoplastics.

The UV-protection films based on renewable materials extracted from natural sources are being one of the most interesting targets for the packaging industry. In this paper, the UV-protection films were produced based on modified lignin and cellulose nanocrystals, both were extracted from the Argania nutshell. The lignin was extracted via the alkylation process followed by chemical modification using epichlorohydrin. The chemical modification and the in-use temperature range of the films were investigated via FTIR and TGA, where the chemical modification of lignin improves the thermal property which is an essential parameter during the thermo-sealing of food packaging. On the other hand, the CNCs were extracted via acid hydrolysis treatment with the smallest size around 300 nm generating smooth texture of films. Finally, the produced films were shown a maximum absorption of the UV light in the range of 450-200 nm and great results in food packaging.

The production of bio-composites based on vulcanized rubber reinforced by natural fibers has been widely studied. However, the aging phenomenon occurring during the long-term storage generating irreversible damage is limiting the performance of this kind of composites which has not been studied in details. So the objective of this work was to characterize and understand the structure-mechanical property relationships in these bio-composites and to correlate the effective crosslinking density with physical aging as a function of fiber content (0, 20, 30 and 40 wt.%) and fiber surface modification (alkali treatment) for the system polyisoprene (PI) and coir fibers. Furthermore, interfacial adhesion was improved by using maleic anhydride grafted polyisoprene as a coupling agent. From the samples produced, a complete set of morphological (scanning electron microscopy) and mechanical (shear and tension) characterization was performed before and after natural aging. The results showed that the tensile modulus increased with fiber content for the range of conditions studied and the presence of a coupling agent always gave higher tensile strength due to better interfacial stress transfer. However, important elasticity loss (strain at break) was observed due to the low fiber elasticity. Finally, different physical aging mechanisms led to changes in the molecular configuration and a reduction of free volume caused by a post-curing phenomenon of the polyisoprene matrix and low environmental stability of the fibers. These phenomena were shown to increase the Young’s modulus of the neat matrix by eight times compared to the unaged neat polyisoprene, but a smaller variation (five times) was observed for the bio-composites which was related to different crosslinking density and coir fibers state of dispersion in the vulcanized matrix

Blends polyamide 6 (PA6) and acrylonitrile-butadiene-styrene (ABS) were compatibilized with a styrene–(ethylene–butene)–styrene triblock copolymer grafted with maleic anhydride (SEBS-g-MA). In particular, the effects of ABS (0–100 wt%) and compatibilizer (0, 8, and 16 wt%) content were studied. The blends were first prepared by twin-screw extrusion, and different specimens were prepared by injection molding. From the samples produced, the effects of blend composition on morphological, mechanical, rheological, and thermal properties are reported. The structural analysis confirmed that the original blend is immiscible but showed some compatibilization when in the presence of SEBS-g-MA. Incorporation of the compatibilizer and ABS showed negligible effect on the melting behavior of PA6. The compatibilized blends showed higher tensile strength compared with uncompatibilized ones. However, Young’s modulus decreased with increasing compatibilizer content. The mechanical results were confirmed by rheological measurements in terms of interaction between each components in the blend.

Polyamide 6 nanocomposites (PA6)/kaolinite were prepared by melt compounding. First, kaolinite was bleached via a solvothermal reaction using oxalic acid as a bleaching agent; then, the bleached product was modified using dimethylsulfoxide (DMSO) and subsequently methanol (MeOH) via a displacement method. Thus, cetyltrimethyl ammonium bromide (CTAB) and triethoxy(octyl)silane (TEOS) molecules were intercalated into kaolinite nano-platelets. Seven types of nanocomposites were prepared using pristine, bleached or intercalated kaolinite. The kaolinite powder and the nanocomposite specimens were characterized by X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), thermal analysis, scanning electronic microscopy (SEM), whiteness index and tensile tests. The influence of the bleaching process of kaolinite and the intercalation methods on the whiteness index of the nanocomposites was also observed, in which the whiteness index of the functionalized kaolinite nanocomposites was enhanced by up to 10.65% when compared to neat PA6. The thermal results revealed that the intercalation and functionalization greatly affect the thermal stability of the virgin polymer. On the other hand, the intercalation of kaolinite enhances the dispersion/distribution, improves the interfacial adhesion, and increases the aspect ratio of the kaolinite nanoparticles; this affords remarkable nanocomposite property enhancements, represented by a high Young's modulus value of 4.68 GPa and a maximum percentage growth of 80.6% for silane-grafted kaolinite nanoparticles at just 8 wt%.

Functional nanocomposites based on a blend of styrene butadiene rubber (SBR) and polyvinylidene difluoride (PVDF) as the matrix reinforced by a hybrid nanofiller system of graphene oxide nanosheets (GOn) and ferromagnetic nanoparticles (Fe3O4) at different weight ratios (3.75:1.25; 2.5:2.5 and 1.25:3.75) were successfully prepared and characterized to determine the effect of nanofillers hybridization in improving the structural,mechanical, dielectric/electrical, magnetic and thermal properties of a polymer blend (PVDF-SBR) for electromagnetic interference (EMI) shielding applications. Due to the synergy between both nanofillers, it was found that the Young’s modulus of the nanocomposite containing 5 wt.% of the hybrid nanofiller was significantly improved (87%), while the strain at yield remained constant due to the low particle content and the rubbery effect of the SBR copolymer. In addition, the degradation temperature of the matrix was shifted from 464°C to 472 °C with the addition of 2.5:2.5 of GOn:Fe3O4. Finally, the hybrid reinforcement also had a positive effect on the electrical and magnetic properties of the nanocomposites with an improvement that exceeds 30%. By careful selection of synthetic techniques and understanding/exploiting the unique physics of the polymeric nanocomposites in such materials, novel functional polymer-inorganic nanocomposites can be designed and fabricated for new interesting in magneto applications such as superparamagnetism, electromagnetic wave absorption, and electromagnetic interference shielding.

This work proposes a benzothiazole derivative bearing a silane moiety as a new coupling agent for polylactic acid (PLA) reinforced by date palm fibers (DPFs). The bio-composites are prepared by solution blending followed by melt compounding. From the samples produced, a complete characterization is performed including morphological, mechanical and thermal properties as a function of fiber content. The results show that the proposed fiber treatment is an easy and effective method to improve the interfacial properties and fiber dispersion leading to better material performance. For example, the addition of only 1 wt% of the dye–IPTMS to the bleached DPF not only improved the thermal stability of the biocomposites, but also led to a significant increase of the Young’s modulus at 7 wt% and higher torsion modulus up to 5 wt% (optimum value).

Expanded perlite is worldwide used material. Due to its low bulk density is used mainly in building materials technology as a filler in lightweight composites, thermal, acoustic, fire insulation as well as in horticulture and agriculture. Due to its extremely low bulk density waste expanded perlite is difficult to handle, utilize and causes dust formation. Paper presents method of utilization of volcanic rock as perlite in two structures (raw or expanded) as a valuable, high performance filler to produce a polymer composites material. The composites were prepared by twin-screw extrusion combined with compression molding at a concentration between 0 and 20 wt %. The effect of reinforcement content and ratio of each particle was studied via morphological (SEM), mechanical (tension), rheological (shear) and thermal (DSC) properties The properties were evaluated in both solid and melt state to determine the mechanical performance of these materials. The results show that better dispersion, distribution and interfacial adhesion of the raw perlite in the PP matrix was achieved compared to the expanded perlite. In general, the mechanical properties and thermal stability of PP were improved with perlite addition. For example, the Young's modulus of raw perlite reinforced composites increased by up to 41% (at 15 wt %) compared to the neat PP.

In the past two decades, polymer nanocomposite materials have tired great interest from both scientists and engineers due to their enhanced properties caused by the addition of nanoscale fillers. New functional nanocomposites have been continually emerging in industry applications. The potential incorporation of the profits of inorganic materials together with those of polymers can allow a wide choice of utilization for these nanocomposites. Hybrid polymer-based nanofillers are generally used as safe and ecofriendly tools to advance crop production in various industrial produce. This chapter summarizes the preparation, characterization, and applications of hybrid polymer nanocomposites based on graphene and clay. Remarkable high elastic modulus and fracture toughness enables the Montmorionite clay and graphene to be used in an enormous number of promising industrial applications also as a reinforcing agent in polymer nanocomposites. Though, irreversible agglomeration of Montmorionite and graphene sheets and the weak compatibility with most polymer matrix limit its potential as a reinforcing agent to fabricate polymer nanocomposites. Synergistic effects by the nanofillers on the nanocomposite’s properties are presented, attempting a rationalization on the basis of the available data.

Cellulose nanocrystal is currently proposed to be used in a wide field of applications such as nanoparticles reinforcement, biopolymer and bio-supporting materials for inorganic nanoparticles. Hybridization is an effective way for making sustainable use of cellulose nanocrystals and inorganic nanoparticles with exceptional properties. This chapter is divided into three parts. The first part focuses on the general aspects of cellulose nanocrystals and their preparation methods. The second part is devoted to the production methods of organic-inorganic hybrid nanocomposite materials and the last part is dedicated to their characterization and applications.

The thermochromic materials that exhibit a reversible change in the color are an attractive class for advanced applications such as smart windows, sensors and printing technologies. In this context, the current chapter introduces these thermochromic composite materials, from their classification to their applications in many industrial fields, passing by the most used methods to synthesize and manufacture thermochromic composite and nanocomposite materials in which their properties are also discussed in order to emphasize their potential.

In this work, biocomposites were produced by compounding polypropylene (PP) with spent coffee grounds (SCG) obtained after soluble coffee preparation. The samples were prepared by extrusion compounding and injection molding using different SCG contents (0, 5, 10, 15 and 20wt.) in order to investigate the effect of particle loading on the thermal, rheological and mechanical properties. Then, the effect of bleaching treatments and the use of compatibilizers (silane and styrene-ethylene-butene-styrene-graft-maleic anhydride) on the biocomposites properties at 15 wt% was examined. The results showed that good SCG dispersion and distribution into PP was achieved and that bleaching led to better interfacial interaction, which was further increased by using a coupling agent. As a result, the tensile and torsion properties were increased.

Polypropylene (PP)/clay nanocomposites were prepared by melt compounding with different grafted clay, such as montmorillonite, halloysite and sepiolite. These clays organically modified by grafting of two organosilanes namely 3-aminopropyltriethoxysilane (APTES) and vinyltrimethoxysilane (VTMS) were used as nanofillers for PP at different concentration (1–5 wt%). The physico-chemical properties of organosilane-modified clay-type were examined by various structural, thermal and morphological analysis routs. According to experimental data, all clays were successfully intercalaced using the silane molecules approved by the decline of the clay nano-particules size, modification of their chemical composition and the increase of their d-spacing. The efficiency of the silylation process as a good way to improve the matrix-fillers interaction was demonstrated by comparing the mechanical characteristics of the clays nanocomposites before and after grafting with organosilanes. Morphological and rheological properties of the PP/clay nanocomposites were also investigated in detail. In conclusion, it was found that the addition of the nano-organoclay allows improving the proprieties of silane grafted clays nanocomposites, which can endorse better interfacial adhesion between the organoclay and the polypropylene and their great spatial dispersion-distribution. The resulting PP/organosilane-grafted clay nanocomposites could be used by industry, or possible fields of application including automotive and construction industries.

The aim of this work is to develop a new bio-composite based on polylactic acid (PLA) reinforced with argan nut shells (ANS). In this study, the effect of ANS chemical surface treatments on the morphological, mechanical, thermal, and rheological properties of PLA was investigated. In particular, a comparison between three chemical treatments (alkali, bleaching, and silane) is made for two filler concentrations (8 and 15% wt.). Scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, dynamic mechanical analysis, and tensile measurements were used to determine the morphology (particle distribution/dispersion/adhesion), thermal stability, mechanical behavior and rheological properties of the bio-composites compared with neat PLA. The results showed that the highest Young's modulus improvement (16%) was obtained with 15% of bleached ANS particles, while the highest tensile strength (1%) and strain at yield (8.5%) improvements were obtained with a silane treatment. These results were associated with good ANS-PLA interfacial adhesion and distribution in the matrix. Nevertheless, lower thermal stability (onset degradation temperature) for all the bio-composites was observed when compared to neat PLA. To complete the characterizations, water absorption and water contact angle were determined indicating better resistance of the bio-composites when ANS surface treatment was applied.

The processing and properties of nano-composites based on a matrix blend of Acrylonitrile-butadiene-styrene/Polyamide6/styrene-butadiene rubber (ABS/PA6/SBR) and filled with Fe3O4 nano-particles are reported in this work. Firstly, a masterbatch of 10 wt% Fe3O4 is prepared by extrusion and then diluted to produce different final content (1, 3 and 5 wt%). The morphological properties reveal a good dispersion and distribution of the nano-particles in the polymer matrix and the thermal stability of the nano-composites shifts towards higher temperature (415–440 °C) as the Fe3O4 concentration increases from 1 to 5 wt%. Furthermore, as the ratio of Fe3O4 increases, the Young’s modulus increases by up to 103% compared to the neat matrix. Finally, the electrical and magnetic properties were found to increase with Fe3O4 content and the highest values were obtained at 5 wt%. In general, it can be concluded that the application range for these nano-composites can be very wide for the thermoplastic matrix selected.

Jute/epoxy hybrid laminated biocomposites were manufactured by using Illite clay particles at various content (5 wt.% − 20 wt.%). The effects of hybridization on the morphology, structure, and mechanical properties were investigated. The properties of the biocomposites reinforced with jute fibers were mainly influenced by the interfacial adhesion between the jute fibers and the epoxy matrix. An alkali treatment was applied to improve the interfacial fiber-matrix adhesion and thus obtaining better mechanical properties. Besides the chemical treatment, epoxy hybridization using clay particles also had a strong effect on the overall properties of laminated biocomposites. The mechanical properties of the jute/epoxy biocomposites reinforced with Illite clay increased with clay content, up to an optimum value at 15 wt.%. The average technique and the laminates theory were performed to validate the coherence of the elastic moduli between the calculated and experimental values. A difference between the experimental and predicted data was observed, which was attributed to the simplifying assumptions made in both models. The laminates theory gave better overall predictions.

In this study, graphene oxide (GO) and graphene nanosheets (GN) were prepared using natural graphite as a reinforcing agent, and different filler contents (1, 2, 3, and 4 wt%) were used to produce nanocomposites based on polyvinylidene fluoride (PVDF). In particular, a melt-blending method was used as a 10 wt% masterbatch was prepared and then diluted to get the final samples via compression molding. A complete characterization in terms of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) confirmed that GO and GN were of high structural quality. Then, the nanocomposites were characterized in terms of thermal, rheological, electrical, and mechanical performances. The thermal stability of neat PVDF (400°C) was found to increase with both fillers addition reaching at 3 wt% 445 and 463°C for GO and GN, respectively. For the same concentration, the PVDF Young's modulus was found to increase by 32% for GN, while only a 7% gain was observed for GO. Similarly, the rheological and electrical resistivity results showed that GN was more effective than GO in improving the performances of these nanocomposites, with an optimum ∼3 wt% for the conditions tested. POLYM. COMPOS., 2017. © 2017 Society of Plastics Engineers

Epoxy-based composite materials are widely used in load-bearing applications, e.g., automotive, aerospace, construction, oil and gas, and marine industries, because of their low cost, good mechanical properties, high specific strength, super adhesiveness as well as good heat and solvent resistance. For this reason, there is a growing need to investigate and predict the deformation behavior of epoxy-based composite materials under general loading conditions. The deformation mode of epoxy-based composites is influenced either by the morphology of the epoxy matrix or by filler loading. In this way, this chapter discusses the chemical composition and structural properties of epoxy polymer as a matrix in composites; the effects of morphological properties of epoxy and fillers on deformation behavior are also discussed, focusing on a literature overview dealing with the mechanisms of damage and rupture of composites based on epoxy and the criteria to predict the deformation behavior under general loading conditions.

In this chapter, graphene oxide (GO) and functionalized graphene oxide were prepared using natural graphite as a reinforcing agent, and different filler contents (1, and 3 wt%) were used to produce nanocomposites based on epoxy resin and woven glass fibers. The silane molecule is used as a grafted function on the graphene oxide surface. The nanocomposites were characterized in terms of mechanical and rheological performances to study the effect of the functionalization on the final performances of nanocomposites.

The graphene oxide has attracted great interest as a nanofiller in many real-world applications due to its importance as a precursor of graphene nanosheets and owing to its special properties (e.g., high mechanical and electric conductivity and low manufacturing cost). Despite aforementioned advantages of graphene oxide (GO) there is one major limitation of the use of the graphene nanosheets in polymer applications is that the layers tend to rearrange into a tactoid structure, leading to agglomeration in the polymer matrix due to their large surface energies generated by the strong van der Waals force experienced by the nanoparticles. Fortunately, GO contains many functional groups, such as hydroxyl, carboxyl, carbonyl, and epoxide, which enable surface functionalization using covalent and noncovalent modification. In this chapter, we investigated the effect of silane functionalization of graphene nanosheets on the thermal and mechanical properties of the thermoset nanocomposites. Before that, a detailed description of the synthesis approaches of graphene nanosheets and their overall properties is given. Furthermore, the surface modification and incorporation routes of graphene nanosheets in the thermoset matrix during their manufacturing are given also.

Nanofibrillated cellulose (NFC), a form of nanocellulose, is currently recommended to be utilized in a wide of industrial applications like food packaging, printing, paper, biomedical, and nanocomposite materials. Their exploitation is not a coincidence, but a fruitful result of many studies showing that NFCs have exciting characteristics such as renewable, sustainable, recyclable, the high length-to-diameter ratio (aspect ratio), and high mechanical properties at the nanometric scale. This chapter is a boon to show the added value of NFCs and their applications in nanocomposites materials. To do this, this content deals with two parts: the first one focuses on the extraction of the NFCs from the cellulosic fiber, their structures, and the processes allowing to modify/treated nanocellulose surface to make it compatible with the polymer matrix. In the second part, focused on the manufacturing process of nanocomposites, their properties and the industrial applications are discussed in depth.

In the last years, serval researches have been focused on organophilic clay as reinforcements for polymer matrices. In this respect, the aim of this chapter is to valorize mineral resources; montmorillonite clay was modified using hexadecyltrimethylammonium bromide (CTAB) and then used as reinforcement in a thermoplastic copolymer matrix to compare with pristine montmorillonite and commercially organo-modified montmorillonite (Cloisite 20A). The nano-composites were prepared by melt compounding using a blend of polyamide 6 (PA6) with acrylonitrile butadiene styrene (ABS) as the matrix. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) as well as mechanical and rheological tests were carried out to understand the properties of these nano-composites at different particle contents. The results obtained clearly showed that the Moroccan montmorillonite was successfully modified and its addition in the selected matrix substantially improved the properties of the resulting nano-composites.

All classes of polymer composites from thermosets to thermoplastics have been used for a wide range of technological applications. With the aim of upgrading natural resources economically, graphite and natural fibers have become exciting natural fillers because they have enhanced thermal, electrical, and mechanical properties of filler-reinforced polymer composites whereas the direct mixing or hybridization of two kinds of fillers is a viable strategy for preparing materials with significant gains in performance and minimal health hazards. This chapter summarizes the effects of several factors such as the shape and size of fillers as well as their distribution, orientation, alignment, and volume fraction and the existence of a strong interface between the charge and polymer matrix on the mechanical properties of prepared composites. Hybrid composites were manufactured using thermoset polymers reinforced with carbon filler and natural fibers. Graphite powders were chemically treated to prepare graphene oxide and then were reduced to form graphene nanosheets or were functionalized using silane molecules. In addition, coir fibers were treated using alkali and bleaching and then were functionalized using the silane molecule. Both fillers were employed to prepare graphite–natural fiber hybrid composites, graphene nanosheet–cellulose nanofibers hybrid nanocomposites, and silane-grafted graphene oxide–silane-grafted cellulose fibers. From the manufactured hybrid composites, the morphological, structural, and mechanical properties were measured and are discussed. The chapter covers the advantages of hybridization of the carbon–coir fillers and their future trends and applications.

In recent years the use of composite materials increased in many fields, for example, woven fabrics are the most used to reinforce the polymeric matrix owing to their high impact resistance, high fatigue resistance, fracture toughness, and damage tolerance characteristics. The main objective of this chapter is to present the cyclic durability of composites reinforced by hybrid woven fabrics to understand the service life of their composites. The advantages and the differences between woven and hybrid woven fabrics are mentioned; also discussed is the influence of environmental aging factors on the fatigue mechanisms, and the cyclic durability characterization of composites. Finally, the modelization and prediction of cyclic durability of hybrid woven composite in the case of natural and synthetic woven are mainly detailed. As well, the factors influencing durability are also established.

Graphene is the thinnest 2-D carbon material and has emerged as a subject of enormous scientific interest due to its exceptional electron transport, mechanical properties, and high surface area. Here we will briefly discuss the different allotropes and forms of carbon (fullerenes, graphene, and carbon nanotubes), followed by a brief review of major techniques developed for synthesizing graphene and graphene oxide that are generally grouped into two major methods classified as top-down and bottom-up processing. Furthermore, the utilization of graphene and graphene oxide in the polymer nanocomposites applications involve a versatile structure functionalization. A significant part of this chapter is devoted to functionalization of graphene and graphene oxide with various species using covalent and noncovalent modifications. A detailed description of the different chemical reactions (nucleophilic substitution, electrophilic substitution, and condensation reaction) and the different interfacial interactions allowing functionalizing graphene networks (π−π interactions, coordination bonds, ionic interactions, van der Waals forces, and hydrogen bonding) is given.

Owing to their unique characteristics, namely low cost, lightweight and unprecedented mechanical and physical properties, composite materials aroused the interest of scientists, making them a promising candidate for tremendous applications. Despite these advantages, the main drawback of these materials is their sensitivity to different climatic parameters, namely temperature, humidity, and radiation, causing their degradation. In this context, this chapter is a summary of (1) damage mechanisms of composite materials based on aging factors having the greatest impact on their durability and (2) a review of the techniques that have been developed to predict life expectancy. Accelerated aging techniques were also chosen to emphasize the adverse effects of weather conditions on the performance of composite materials.

Hybrid composite materials are the result of a combination of several phases where at least two reinforcement elements are integrated into a matrix to improve the composite's properties. The morphology, nature, and orientation of components are significantly affect the manner that composite react against solicitations. In fact, the properties of the composite are closely linked to its internal structures, which are governed by the characteristic properties of the constituent elements of the composite. The heterogeneity problem of composite materials at the microscopic level makes it difficult to move toward a homogeneous global level where the behavior of the material can be measured. In this chapter, the classifications of composite materials and filler types are presented. Then, the renowned analytical models, including the Voigt and Reuss method, Hirsh's method, Tsai's model, other analytical models, are discussed. Next, a review of proposed models for the properties of the hybrid composite material in two cases is debated, beginning with numerical modeling of fiber hybridization using the linear rule-of-mixture of Zweben and Fukuda, and finishing with numerical modeling of hybrid particulate fiber-reinforced composites using three approaches: representative volume element, representative unit cell, and object-oriented modeling.

In this work, Illite (natural Moroccan clay) was selected to reinforce high density polyethylene (HDPE) and to determine the efficiency of styrene-(ethylene-butene)-styrene triblock copolymer grafted with maleic anhydride (SEBS-g-MA) as a coupling agent. The composites were prepared by extrusion followed by injection molding of various clay contents (5–40 wt%). From the samples produced, the morphological, thermal, mechanical, and rheological properties were measured. The results showed that interfacial adhesion was improved with coupling agent addition leading to increased Young's modulus, as well as higher tensile strength, and strain at yield. Nevertheless, the maximum value for the composites without SEBS-g-MA (57% modulus increase) was obtained at 20 wt% compared to 15 wt% for the composites with SEBS-g-MA (45% modulus increase). The thermal stability of the composites also increased with clay content, especially when the coupling agent was added. Finally, water absorption tests revealed that the composites have a higher tendency to absorb water with increasing clay content, but the use of a coupling agent substantially reduced this problem. POLYM. COMPOS., 2016. © 2016 Society of Plastics Engineers