Grafting Of Maleic Anhydride Research Articles

Interface Structure and Properties of Polypropylene/Wood Flour Composites Reinforced with Grafted Polypropylene Compatibilizer

AbstractIn this work, a new compatibilizer, ternary monomer grafted polypropylene (hereafter shorted as: G‐PP), was successfully synthesized by solid phase grafting of maleic anhydride, methyl methacrylate, and butyl‐acrylate onto polypropylene. For all developed polypropylene matrix composites, the prepared G‐PP evidently showed enhancing mechanical properties on PP/wood flour (WF) composites, which is obviously superior to those from maleic anhydride grafted polypropylene (W‐PP) and virgin polypropylene (C‐PP). In particular, the wettability of G‐PP was greatly improved, while the melting temperature and β crystal phase amounts of the WF composites with G‐PP are much higher when compared to that of W‐PP and C‐PP. This can be reasonably explained by the formation of continuous micropores and filaments in WF composites containing G‐PP, as verified by hot stage polarizing optical microscope (POM). Meanwhile, the G‐PP effectively reduced movement of molecular chains of WPC and formed a better interface layer with WF, which contributed to penetrate more deeply and form micro‐crosslinking in the WF layer. We believe that the results reported in this work will increase the added value of polypropylene based wood plastics composites (WPC) and allow WPC to participate in lightweight and environmentally friendly products.

Enhancement and Compatibilization of Waste-Sourced Biocomposites Through Elastomer Blending and Matrix Grafting Modification

A novel elastomer-modified multicomponent, multiphase waste-sourced biocomposites, was prepared for converting waste biomass and plastic into value-added products. The effects of blending elastomer–olefin block copolymer (OBC) and maleic anhydride (MAH), and divinylbenzene (DVB) co-grafting of recycled polypropylene (rPP) matrix on the adhesion interface, structure, and properties of high wood flour-filled (60 wt.%) composites were thoroughly investigated. The results indicated that DVB introduced branched structures into the polymer matrix molecular chain and increased the MAH grafting rate. Co-grafting rPP/OBC blends enhanced the interfacial adhesion among rPP, OBC, and wood flour. Additionally, MAH-grafted OBC was prone to encapsulating rigid wood flour, thereby forming an embedded structure. Notably, the tensile modulus and impact strength of the final three-component composites increased by 60% and 125%, respectively, compared with the unmodified composites. Additionally, dynamic mechanical analysis revealed that DVB-induced branching promoted the formation of microvoids in the OBC shell layer surrounding the wood, which in turn induced significant plastic deformation in the polymer matrix. This work offers a facile and efficient method for preparing high-toughness, high-stiffness, and low-cost waste PP-based composites for automotive interiors, and indoor and outdoor decoration.

Grafting of maleic anhydride onto waste acrylonitrile butadiene styrene (ABS) and its application for compatibilization of ABS blends

AbstractIncorporating recycled plastics into the manufacturing process is an essential way to establish a sustainable plastics economy. However, current processes are limited by the degradation of mechanical properties, high cost, and inconsistent product quality compared with their virgin counterparts. Here, we present an upcycling strategy for waste plastics where waste acrylonitrile‐butadiene‐styrene (reABS) is first grafted with maleic anhydride (MAH), then utilized to compatibilize nylon 6(PA6)/ABS and PA6/ABS/CaCO3 blends. The reABS‐g‐MAH exhibits improved Young's modulus and tensile strength, but lower strain at break and impact strength compared with reABS. As an additive, reABS‐g‐MAH effectively compatibilizes PA6/ABS and PA6/ABS/CaCO3 blends, indicated by greatly decreased PA6 domain size, homogeneous dispersion of fillers, and narrowed glass transition temperature regions between PA6 and ABS. Adding only 5 wt% reABS‐g‐MAH increases the Young's modulus, strain at break, and impact strength of PA6/ABS blends by 26%, 180%, and 110%, respectively, compared with uncompatibilized samples. Similarly, for PA6/ABS/CaCO3 blends, the strain at break and impact strength increase by 370% and 150%, respectively, while the Young's modulus and tensile strength show increases of 5% and 10%. The results show that this strategy of using polar groups to functionalize waste plastics as compatibilizers may open numerous opportunities for upcycling waste plastics.

Biodegradation Behaviour of the Composite Consisting of Polypropylene and Bauhinia Vahlii Fiber

AbstractThe current study focuses on the degradation rate of polypropylene (PP) and Bauhinia Vahlii (BV) fibers under soil burial and natural weathering conditions for 360 days. The BV‐PP composite was produced with varying BV fiber compositions (0, 10, 20, and 30 wt.%) and 3 % MAPP (Maleic Anhydride Grafted Polypropylene). In addition, MAPP is employed as a coupling agent to improve fiber‐matrix compatibility and promote degradation. The XRD examination shows that a 10 % BV‐PP composite has a crystallinity index of 52.05 %, which is higher than that of neat PP. The rate of biodegradability was investigated using weight loss and tensile properties. The largest degradation was seen in natural weathering conditions with 30 % composite showing the maximum weight loss of 3.8 % and loss in tensile strength and modulus of 16.76 % and 5.11 %, respectively. Simultaneously, no weight loss or drop in tensile characteristics was found in the case of neat PP over 360 days. The SEM images of soil burial show material deterioration, which may be aided by bacterial and fungal activity, whereas natural weathering conditions show a large crack, rougher fracture surface, and cavities, which are attributed to thermal stresses, changes in moisture content, and ultraviolet radiation, thereby promoting the degradation process.

Peroxide free radical grafting of maleic anhydride onto polyethylene under high melt temperature: A comprehensive approach

“Flash Reactive Extrusion” under very high temperatures (T=200–420°C) allowed to graft maleic anhydride onto polyethylene (PE) without the use of conventional free radical initiators such as peroxides. Herein, the use of unusual temperatures induced the formation of radicals through degradation/chain scission of the PE backbone and the latter radicals were able to react with maleic anhydride (MA) and yielding a MA grafting degree close to 1.4 wt% at 390°C. Moreover, the MA grafting mechanistic scheme was deeply discussed with the help of 1H NMR and 13C NMR analysis and it was pointed out that β-scissions reactions are favoured in comparison with the cross-linking ones at very high temperatures for the thermal initiation step with a MA grafting mainly onto the PE side chain.

Enhanced energy density of BOPP film by MAH grafting for metallized capacitors

In this paper, maleic anhydride (MAH) was grafted on the surfaces of biaxially oriented polypropylene (BOPP) film by ultraviolet irradiation treatment to improve the breakdown strength. The addition of MAH, with abundant deep traps, effectively hinders charge injection from the electrode, leading to improved dielectric performance, particularly at elevated temperatures. The experimental results show that the received modified film exhibits an improved permittivity of 2.37 alongside a low dielectric loss of 0.0022 at 1000 Hz. Remarkably, the DC breakdown strength reaches 633.9 kV mm−1, marking a notable 21.4% increase compared to the unmodified BOPP film at 120 °C. Moreover, the film exhibits an energy density of 2.58 J m−3, which is 1.59 times that of the pure film. The charging and discharging efficiency is also greatly improved due to the reduction of conductance losses. Through simulation results, it becomes evident that the enhanced performance is attributed to the alleviation of electric field distortion due to the suppression of injected charge. This work paves a facile route to design scalable polymeric dielectrics with outstanding performance, which facilitates the development of film capacitors.

Ionic Cross-Linking of Polypropylene: Effect of Maleic Anhydride Grafting Temperature and Ionic Plasticizer

Ionic Cross-Linking of Polypropylene: Effect of Maleic Anhydride Grafting Temperature and Ionic Plasticizer

Optimization of malic anhydrate concentration in manufacturing PP-g-MA compatibilizer on test percent of grafting degree

The difference in polarity means that two or more materials cannot react, a connecting material such as a compatibilizer is needed to react between polar and non-polar materials. This research aims to determine the effect of maleic anhydride (MA) concentration on the process of grafting MA onto polypropylene (PP) chains with the help of benzoyl peroxide (BPO) as an initiator. The method used to mix these two materials uses the blending method using an internal mixer instrument and testing the percent degree of grafting using the titration method with three repetitions of the test.The research results showed that the highest percent grafting degree occurred at a concentration of 86% PP, 11% MA, and 3% BPO, with a value of 10.28%. The Spectroscopy Fourier Transform Infrared (FTIR) analysis of Polypropylene grafted maleic anhydride (PP-g-MA) showed the presence of new peaks at wavenumbers 1707cm-1 and 1162 cm-1.Increasing the concentration of maleic anhydride had no effect on increasing the percent degree of grafting.

Kinetics in high-temperature free-radical reactive processing: Grafting maleic anhydride onto polypropylene in the presence of nanoclay-supported peroxide

The kinetics of grafting and chain scission reactions during maleic anhydride (MA) grafting onto polypropylene (PP) using nanoclay-supported peroxide (o-MMT/DCP) in the molten state were evaluated through the development of a new methodology. A combination of characterization techniques and mathematical data manipulation was employed for this assessment. To inhibit radical propagation and recombination, tetramethylpiperidine-1-oxyl (TEMPO) was used as a free radical scavenger. Rheological stability tests demonstrated that TEMPO was more effective as a reaction inhibitor. The kinetics dataindicated that the use of o-MMT/DCP resulted in products with higher MA grafted levels and molecular weight (MW) compared to grafting performed in the absence of o-MMT. Additionally, some changes in molecular architecture were observed. The chain scission distribution function (CSDF) revealed that during the MA grafting process, the molecular weight of PP was reduced through chain scission, with a preference for longer chains. Furthermore, the presence of o-MMT was found to restrain the level of PP chain scission, likely due to recombination on the clay surface.

Synthesis of acylated derivatives of alginate oligosaccharides and evaluation of their potential antibacterial activities against Staphylococcus aureus

Alginate oligosaccharides (AOS) are crucial carbohydrate-based biomaterial used in the synthesis of potential drugs and biological agents, but their antibacterial activities are not significant. In this study, AOS acylated derivatives were synthesized by grafting maleic anhydride (MA) onto AOS at varying ratios. Additionally, their inhibitory effects against Staphylococcus aureus were thoroughly investigated. Characterization of the AOS acylated derivatives (AOS-MA-x, where x = 1, 5, 10, and 20) was conducted using Fourier-transformed infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy, and X-ray diffraction, which confirmed the successful synthesis of these derivatives. The bacteriostatic activity of the AOS-MA derivatives was assessed using growth curves and plate coating method, demonstrating significant antibacterial effects against S. aureus, as compared with AOS. Among these derivatives, AOS-MA-20 exhibited the most potent bacteriostatic activity and was selected for further investigation of its inhibitory mechanism. Scanning electron microscopy analysis revealed that treatment with AOS-MA-20 led to the lysis and rupture of S. aureus cells, expelling their intracellular contents. Moreover, AOS-MA-20 disrupted the integrity of cell wall and cell membrane, impacted ATPase activity, and inhibited the formation of biofilm to some extent, ultimately resulting in bacterial death. These findings lay a foundational framework for the development of environmentally friendly antimicrobial agents.

Experimental and theoretical investigation of the effect of physical and chemical compatibilization on the properties of thermoplastic elastomers derived from natural rubber and polypropylene blends

The objective of this research was to improve the compatibility between Natural Rubber/Polypropylene NR/PP blends through physical and chemical compatibilization methods. The physical compatibilization involved the use of epoxidized natural rubber/maleic anhydride-grafted polypropylene (ENR50/PP-g-MA) as a dual compatibilizing agent (CA50), while the process of reactive compatibilization entailed chemically modifying NR and PP phases through the grafting maleic anhydride (MA). Several formulations were prepared by melt mixing using a Brabender plasti-corder. The effects of physical and chemical compatibilization on the technical properties were investigated. FTIR analysis revealed the emergence of two distinctive peaks corresponding to the CO group of MA grafted onto PP and NR chains. FTIR analysis has also confirmed the taking place of reactions between the polar functional groups of PP-g-MA and ENR50. The rheological properties indicated that the viscosity of the NR-g-MA/PP-g-MA is lower than those of the control blend and CA50-based NR/PP system. The mechanical and dynamic mechanical findings corroborated the improvement of interfacial adhesion between NR/PP phases, especially for the NR/PP/CA50 system. SEM examination demonstrated a more uniform dispersion of the PP phase in the CA50-based NR/PP, compared to the control blend and NR-g-MA/PP-MA. NR-g-MA/PP-g-MA exhibits greater miscibility and interaction potential compared to the control NR/PP, and less than NR/(ENR50/PP-g-MA)/PP system. DFT calculations further validate the effect of compatibilization methods on TPE blends. Specifically, Quantum molecular descriptors revealed the role of ENR50/PP-g-MA as an intermediary in facilitating compatibility between NR/PP. These findings indicate that the physical compatibilization method approach using ENR50/PP-g-MA as a dual compatibilizer is a potential compatibilizer for NR/PP.

Tailoring Polyamide Nanocomposites: The Synergistic Effects of SWCNT Chirality and Maleic Anhydride Grafting

Tailoring Polyamide Nanocomposites: The Synergistic Effects of SWCNT Chirality and Maleic Anhydride Grafting

Improving the Barrier and Mechanical Properties of Paper Used for Packing Applications with Renewable Hydrophobic Coatings Derived from Camelina Oil.

This study looked at using modified camelina oil to develop sustainable coatings that could replace those derived from petroleum-based materials for use in packaging and other industrial sectors. Solvent-free synthesis of maleic anhydride grafted camelina oil (MCO) was carried out at two different temperatures (200 and 230 °C) to obtain sustainable hydrophobic coating materials for paper substrates. Maleic anhydride grafting of camelina oil was confirmed with attenuated total reflectance-Fourier transform infrared and NMR spectroscopic techniques, and up to 16% grafting of maleic anhydride was achieved, as determined by the titration method. MCO, obtained at different reaction temperatures, was coated onto cellulosic paper and evaluated for its hydrophobicity, mechanical, oxygen, and water vapor barrier properties. Scanning electron microscopy indicated the homogeneous dispersion of coating material onto the paper substrate. MCO-coated papers (MCO-200C paper and MCO-230C paper) provided a water contact angle of above 90° which indicates that the modified oil was working as a hydrophobic coating. Water vapor permeability (WVP) testing of coated papers revealed a reduction in WVP of up to 94% in comparison to the uncoated paper. Moreover, an improved oxygen barrier property was also observed for paper coated with both types of MCO. Analysis of the mechanical properties showed a greater than 70% retention of tensile strength and up to a five-fold increase in elongation at break of coated versus uncoated papers. Overall, the results show that camelina oil, a renewable resource, can be modified to produce environmentally friendly hydrophobic coating materials with improved mechanical and water vapor barrier properties that can serve as a potential coating material in the packaging industry. The results of this research could find applications in the huge paper packaging industries, specially in food packaging.

Inspection of microwave self‐healing efficiency in carbon nanotube reinforced polymer composites for aerospace applications

AbstractThe aerospace industry is evolving very rapidly every day, and due to the low operational and maintenance costs, unmanned aerial vehicles (UAVs) are utilized for many duties, including imaging, patrol, surveillance, and delivery. Flying platforms prioritize effective load‐carrying capacity and light weight. To achieve this, lightweight materials with sufficient strength are utilized, and design optimizations are implemented. This study investigates material development for a UAV propeller, taking into account the possible consequences of a bird strike or hard landing such as micro damage occurrence. In this study, a twin‐screw extruder was used to produce hybrid composites by blending a thermoplastic, polyamide‐6 (PA6) with olefin block copolymers (OBC) and carbon nanotubes (CNT). After manufacturing test specimens by injection molding, tensile and Charpy impact tests were performed. OBC increased the elongation capacity and impact resistance of the PA6 through maleic anhydride (MAH) grafting while reducing the tensile strength. CNT incorporation compensated for this drop, but it rendered the composites more brittle. More importantly, due to the CNT's microwave (MW) absorption capacity, the hybrid composites have gained self‐healing properties. Extended MW exposure time and high MW powers may cause localized burning of the material, resulting in a decrease in its self‐healing efficiency. Following the failure of the examined composites, SEM microscopy revealed various toughening mechanisms in the composites. The use of a modified Halpin‐Tsai model to estimate the elastic characteristics of CNT‐reinforced composites revealed promising results, with minimal discrepancies when compared to experimental data.Highlights CNTs were found efficient for the self‐healing behavior which is critical for improving the lifetime and planning maintenance for UAV propellers. CNT content, MW power & exposure time all impact the self‐healing efficiency. Extended MW exposure time and high MW powers can cause localized burning of the material, resulting in a decrease in its self‐healing efficiency. CNTs created bridge effects, ultimately leading to an enhancement in the strength of the composites. The use of a modified Halpin‐Tsai model yielded good accuracy with experimental data.

Compatibilization of Polyamide 6/Cyclic Olefinic Copolymer Blends for the Development of Multifunctional Thermoplastic Composites with Self-Healing Capability.

This study investigated the self-healing properties of PA6/COC blends, in particular, the impact of three compatibilizers on the rheological, microstructural, and thermomechanical properties. Dynamic rheological analysis revealed that ethylene glycidyl methacrylate (E-GMA) played a crucial role in reducing interfacial tension and promoting PA6 chain entanglement with COC domains. Mechanical tests showed that poly(ethylene)-graft-maleic anhydride (PE-g-MAH) and polyolefin elastomer-graft-maleic anhydride (POE-g-MAH) compatibilizers enhanced elongation at break, while E-GMA had a milder effect. A thermal healing process at 140 °C for 1 h was carried out on specimens broken in fracture toughness tests, performed under quasi-static and impact conditions, and healing efficiency (HE) was evaluated as the ratio of critical stress intensity factors of healed and virgin samples. All the compatibilizers increased HE, especially E-GMA, achieving 28.5% and 68% in quasi-static and impact conditions, respectively. SEM images of specimens tested in quasi-static conditions showed that all the compatibilizers induced PA6 plasticization and crack corrugation, thus hindering COC flow in the crack zone. Conversely, under impact conditions, E-GMA led to the formation of brittle fractures with planar surfaces, promoting COC flow and thus higher HE values. This study demonstrated that compatibilizers, loading mode, and fracture surface morphologies strongly influenced self-healing performance.

A new approach for grafting plasticized cellulose acetate biodegradable plastic with maleic anhydride: Processing and characterization

AbstractGrafting polymers with reactive maleic anhydride is a common approach for the synthesis of new material with the capability of acting as a compatibilizer in polymer blends. Accordingly, this research showed a new approach for grafting maleic anhydride onto renewable cellulose acetate using an initiator. The grafting process through extrusion showed good stability with continuous production of all grafted samples. Moreover, two different grafting processes, namely one‐step and two‐step processes, were shown to produce materials with very similar characteristics. Grafting of maleic anhydride onto cellulose acetate by reacting with its hydroxyl groups was confirmed by both Fourier transform infrared spectroscopy and nuclear magnetic resonance analysis. Rheological studies also demonstrated the enhanced flowability and lower viscosity of the grafted material in comparison to the plasticized cellulose acetate.Highlights Grafting maleic anhydride onto plasticized cellulose acetate by reactive extrusion. Detection of grafted maleic anhydride onto cellulose acetate through NMR analysis. High thermal stability of grafted materials. Significant reduction in viscosity of plasticized cellulose acetate after grafting

Salt resistant and self‐cleaning CNTs‐SEBS‐MAH composite membrane for seawater desalination

AbstractSolar‐driven steam generation membranes have garnered increasing attention for freshwater production. Nonetheless, the adverse impact of salt accumulation on membrane surfaces directly undermines the efficacy of solar evaporation. In this work, one type of composite membrane comprised of carbon nanotubes (CNTs)‐styrene‐ethylene‐butadiene‐styrene (SEBS) was fabricated by modified vapor phase pore‐forming technique. Through the grafting of maleic anhydride (MAH), the CNTs‐SEBS‐MAH composite membrane was successfully hydrolyzed. As a consequence, the composite membrane exhibits evaporation rate as high as 1.28 kg m−2 h−1 under one sun solar irradiation, accompanied by an outstanding solar vapor conversion efficiency of 87.5%. In addition, the fabricated composite membrane has high resistance to salt accumulation, as well as self‐cleaning capability. This work provides a route for manufacturing hydrophilic polymer composite membrane towards solar energy driven seawater desalination.

Polypropylene nanocomposites produced by in‐situ grafting of maleic anhydride using different mixing procedures

AbstractNanocomposites (NC) of polypropylene (PP) and organophilic montmorillonite (oMt) are produced by reactive mixing with simultaneous grafting of maleic anhydride (MA) onto PP using organic peroxide as initiator. Five different strategies of incorporating reactants and clay into a laboratory mixer are used. The structure of composites is examined by FT‐IR spectroscopy, x‐ray diffraction and scanning electron microscopy. Rotational rheometry, thermogravimetry and oxygen permeability are used to evaluate properties. The preparation method has a remarkable influence on NC's structure. Simultaneous addition of peroxide and MA to molten PP followed by incorporation of clay 20 minutes later produces the best degree of clay exfoliation/disaggregation. The NCs obtained using this procedure are highly transparent and have very thin tactoids with interlayer spacing more than 50% larger than the original oMt. The incorporation of just 2 wt% of clay gives place to more than 30% reduction in PP oxygen permeability. Additionally, the temperature at the maximum thermal degradation rate in nitrogen reduces in about 60°C while the temperature at which the thermal degradation process begins is not affected.Highlights Highly intercalated/exfoliated PP/oMt nanocomposites are synthesized Reactive mixing procedure affects the quality of nanocomposite's structure A initial period of grafting before clay addition is the most effective method Highly transparent materials with small tactoids of d001>4 nm is generated PP oxygen permeability is highly reduced by the use of just 2 wt% of nanoclay

A polyamide and polyethylene multilayer composite with enhanced barrier and mechanical properties at high temperature

An advanced multilayer thermoplastic composite, composed of Polyethylene of Raised Temperature (PERT), Polyamide 12 (PA12), and Maleic Anhydride Grafted Polyethylene (MA), has been developed for high-temperature, high-pressure applications.

Functionalized sepiolite intercalated graphene nanostructure reinforced polypropylene composites

The present work developed hybrid polypropylene (PP) ternary composites using PP with different contents of amine-functionalized sepiolite intercalated graphene (f-Sep-Gr) nanofillers through the melt blending method. The amine functionalization on sepiolite intercalated graphene (Sep-Gr) nanostructure was carried out using 3-amino propyl triethoxyl silane. Fourier Transform-Infra Red (FT-IR), X-ray Photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) analysis confirmed the successful functionalization of the amine group into Sep-Gr. Transmission Electron Microscopy (TEM) analysis also confirmed that the amine functionalization didn’t disturb the Sep-Gr morphology. Maleic anhydride graft polypropylene (PP-g-MA) was employed as an interfacial compatibilizer to enhance the dispersion of f-Sep-Gr into the continuous PP phase via a perfect covalent bond interaction. X-ray diffraction (XRD) analysis showed a complete distribution of f-Sep-Gr into the PP/PP-g-MA blend matrix, and the intercalated structure of f-Sep-Gr was not adversely disturbed in the composite. Melt rheological analysis revealed that the composite consisting of the lower content of f-Sep-Gr (0.5 wt%), resulting in a viscous behavior, and a further increase in the content of f-Sep-Gr into the PP/PP-g-MA blend showed viscoelastic solid-like behavior. Differential scanning calorimetry (DSC) analysis revealed that the f-Sep-Gr did not accelerate the melt-crystallization process of PP. In addition, thermogravimetry analysis (TGA) showed that the thermal stability of PP/PP-g-MA/f-Sep-Gr composites improved as a function of f-Sep-Gr content. A small amount of f-Sep-Gr (0.5 wt%) increased Young’s modulus and impact strength of the PP matrix, which is about 123% and 266%, respectively, compared to pure PP. TEM analysis ensured the incorporation of a small fraction of f-Sep-Gr into the blend matrix, forming a three-dimensional network structure in the composite.