Maleic Anhydride-modified Polypropylene Research Articles

Effect of Zeolite Mineral on the Formulation of a Wood-plastic Composite

The present work studies the positive or negative effect of zeolite mineral on the tensile and flexural mechanical behavior of a wood-plastic composite. Eight different blends were developed, the components used were wood flour (WF), polypropylene (PP), zeolite (Z) and maleic anhydride modified polypropylene (MAPP) as coupling agent. The eight blends were made using a counter-rotating twin-screw extruder, while the specimens were produced on a plastic injection molding machine with a 60ton clamping capacity. The standards used to determine the tensile and flexural mechanical properties were ASTM 638 and ASTM 790, respectively. Ten repetitions of each mixture were carried out. In addition, a reference (100% polypropylene) was used to compare the results obtained to determine whether the effect of using the zeolite mineral generated positive or negative results in the compounds obtained. Both studies showed that as the proportion of zeolite increases in the blend, the tensile and flexural properties are affected. However, the mixture (M7) with proportions in its components of, 34.375% WF, 55.875% PP, 6.75 % Z and 3% MAPP, showed an increase in the tensile and flexural mechanical properties, indicating a strong relationship between the components that integrate the wood-plastic composite (WPC), mainly between wood and mineral.

Effects of different types of maleic anhydride-modified polypropylene on the interfacial shear strengths of carbon fiber-reinforced polypropylene composites

Effects of different types of maleic anhydride-modified polypropylene on the interfacial shear strengths of carbon fiber-reinforced polypropylene composites

Effect of MAPP on Interfacial Shear Strength of PP/Rice Straw Fiber Composites

Polypropylene (PP) composites filled with rice straw fiber were prepared and characterized to contribute to the realization of a low-carbon society. Generally, the mechanical properties of composites composed of cellulose fiber such as rice straw fiber and nonpolar polymer such as PP decrease due to poor interfacial adhesion. This paper reports the compatibilizer effects of maleic anhydride modified polypropylene (MAPP) on the mechanical properties of PP/rice straw fiber composites. As a result, interfacial shear strength (IFSS) between resin and fiber measured by a short beam test changes with the MAPP content, reaching a maximum value at 1 phr as a similar trend as changes in their tensile strength. Therefore, the improvement of tensile strength indicates the enhancement of interfacial adhesion between PP and rice straw fiber.

Fluorescent labeling and image analysis of cellulosic fillers in biocomposites: Effect of added compatibilizer and correlation with physical properties

The performance of cellulosic filler/polyolefin biocomposites is affected by the filler dispersion (aggregation and spatial arrangement) in the matrix. However, this mechanistic factor is generally inferred from the physical properties of the final bulk material because of the limitations of analytical techniques. Herein, we propose a simple method to quantitatively evaluate the dispersion of filler particles. To accomplish this, the cellulose component in injection-molded specimens of microcrystalline cellulose (MCC)/maleic anhydride-modified polypropylene (MAPP)/polypropylene (PP) composites was selectively fluorescently labeled with calcofluor white, and the dispersion state of tens of thousands of MCC particles observed by fluorescence microscopy was analyzed. The close-range aggregation behavior of the MCC particles can be evaluated by the area of the fluorescent particles (A), and the normality (randomness) of the spatial arrangement can be classified by the skewness of the distribution of the distances between the centroids of the particles (s). As a result, with an increase in the degree of acid modification of the added MAPP, aggregation of MCC was suppressed and the spatial arrangement became random. Both A and s were not associated with the modulus or fracture strain of the injection-molded specimens, but they were correlated with the tensile and bending strengths and water absorption behavior. This visualization method was also applied to a composite containing nanofibrillated cellulose filler (citric acid-modified cellulose nanofiber).

Effects of Premixing Wood Flour with Compatibilizer with Different Characteristics on the Physical and Mechanical Properties of Wood/Plastic Composites

Abstract The addition of maleic anhydride (MA)-modified polypropylene (MAPP) as a compatibilizer increases mechanical and physical properties of wood/plastic composites (WPCs). It is thought that MA graft ratio (Gr), molecular weight (weight-average molecular weight [Mw]), and mixing methods of MAPP affect physical and mechanical properties of WPCs. However, evaluation, especially for mixing order, is not enough. The objective of this study was to investigate the effect of Gr and Mw of MAPP and its mixing methods on the mechanical and physical properties of WPCs. Two types of mixing methods were used: mixing the MAPP with the filler using a Henschel mixer before kneading with PP (premixing method) and mixing all of the materials at one time (one-step mixing method). The WPCs made with the premixing method had lower shear viscosity and higher flexural modulus than those made with the one-step mixing method. The particle size, moisture content, and surface morphology of fillers are thought to be more important in determining the shear viscosity of WPCs than the MAPP itself. The highest tensile, impact, and flexural strengths of WPCs were obtained in the WPC with premixing with low-Gr and high-Mw MAPP. It may be due to the effective reaction of the wood flour with MAPP and higher entanglement between the MAPP and PP. These results suggest that the premixing method could improve productivity and mechanical properties of WPCs.

Butylated lignin as a compatibilizing agent for polypropylene-based carbon fiber-reinforced plastics

Lignin is a renewable resource, but it is also considered a waste or a very-low-value material. Herein, we propose a lignin-derived compatibilizing agent as an alternative to the current compatibilizing agents. We prepared a polypropylene-based carbon fiber-reinforced plastic (CFRP) with butylated lignin (C4 lignin). Upon the addition of C4 lignin, the dispersion of carbon fiber into the matrix, and the adhesion between the carbon fiber and the matrix were greatly improved. As a result, the tensile strength of the CFRP prepared with C4 lignin was greater than that of the CFRP without lignan lignin (37.1 compared to 40.2 MPa). This value is close to that of CFRPs prepared with maleic anhydride-modified polypropylene (40.9 MPa), an existing compatibilizing agent. C4 lignin is a promising candidate for biomass-derived compatibilizing agents for polypropylene-based CFRPs.

The Effects of Different Types of Maleic Anhydride-Modified Polypropylene on the Physical and Mechanical Properties of Polypropylene-based Wood/Plastic Composites

Maleic anhydride-modified polypropylene (MAPP) is a compatibilizer used to improve the physical and mechanical properties of many wood/plastic composites (WPCs). The properties of WPCs containing MAPP differ according to the characteristics of the specific MAPP that it is used. In this study, the physical and mechanical properties, including shear viscosity, of polypropylene-based WPCs containing different types of MAPP were investigated before and after water absorption. The shear viscosity of MAPP increased with increasing molecular weight, but remained nearly constant for WPCs containing different types of MAPP. In dry conditions, the strongest WPC contained the MAPP with the highest acid value. The highest flexural modulus was observed with the WPC containing the MAPP with the highest molecular weight. In wet conditions, the WPC exhibiting the best mechanical properties contained a MAPP with a molecular weight of 58,000.

Direct spectroscopic detection of binding formation by kneading of biomass filler and acid-modified resin

Compatibilizers added into filler-reinforced polymer composites are supposed to bring about the enhancement of mechanical properties by binding with the filler and entanglement with the polymer matrix. We elucidated the binding of maleic anhydride-modified polypropylene (MAPP) compatibilizer and microcrystalline cellulose (MCC) filler. This is usually not readily detectable by spectroscopy. For this, we adopted a set of enzymatic digestion and refined but simple spectroscopy. A series of binary composites of MCC and MAPP was prepared by kneading. By the cellulolytic treatment and an adequate heat processing, we obtained clear IR signals due to the binding. Furthermore, by gel (swollen)-state NMR method which has attracted attention for analyzing plant cell wall, we acquired interface-specific liquid-state NMR spectra giving the information of the bonds between these components insoluble in commonly used solvents. Such analytical methods provide a useful perspective on the relationship between the microstructure and compatibility of composite materials.

RICE STRAW/THERMOPLASTIC COMPOSITE: EFFECT OF FILLER LOADING, POLYMER TYPE AND MOISTURE ABSORPTION ON THE PERFORMANCE

ABSTRAT Thermoplastic composites made with 45, 60 and 75% of rice straw as filler and two types of thermoplastics, virgin polyethylene (PE) and polypropylene (PP) were evaluated. The final boards were made with and without maleic anhydride modified polypropylene (MAPP) at 2% of the total weight of each specimen. The flexural and tensile strengths were measured for dry composites and also measured after 24 h of water immersion of the composites (wet condition). By increasing the filler content, the flexural and tensile strengths and also the density of the specimens decreased. The type of matrix (PE or PP) did not affect significantly the flexural strength, but PP led to higher values of tensile strength for low fiber loadings (45% and 60%). Coupling agents increased the flexural and tensile strength. After water immersion, modulus of elasticity and modulus of rupture were decreased, while tensile strength was less influenced.

Effect of Steamed and Non-Steamed Populus deltoides Fiber on the Physical, Mechanical, and Morphological Characteristics of Composites Made from Virgin Polypropylene

The effects of steamed Populus deltoides fiber were studied relative to the physical, mechanical, and morphological characteristics of composites made from virgin polypropylene. Fibers of Populus deltoides were used during the reinforcement phase at 180 °C for 1 h. The tests were carried out with 57% of virgin polypropylene that was combined with 3% of maleic anhydride-modified polypropylene and 40% of wood fiber. The wood fiber portion consisted of either non-steamed fiber, steamed fiber, and an equal mixture of the two kinds of fiber. Mixing was done using an internal mixer at 180 °C and 60 rpm, and the standard samples were constructed by injection molding. Then, the physical and mechanical characteristics of samples were measured. To consider compatibility between the matrix and reinforcement phase, SEM pictures were taken from the break surface of composite samples. The results showed that the composites’ strengths were affected by steam, as components having steamed fibers had the best mechanical strength and dimensional stability, and also the least water absorption and thickness swelling.

Commingled composites of polypropylene/coir-sisal yarn: effect of chemical treatments on thermal and tensile properties

AbstractEco-friendly bio-composite of polypropylene (PP)/coir-sisal blended yarn was prepared using commingling technique, in which both the fibers are wound onto a metal plate and then compression molded. Various chemical treatments have been done in order to improve the interfacial adhesion between the matrix and reinforcement, thereby to increase the properties of the composite. Thermal stability study was done using thermogravimetric analysis. The resulting thermogram reveals that chemical treatments increase the thermal stability of the commingled composite to a considerable extent. A significant increase is observed in the tensile properties of the treated composite especially maleic anhydride modified PP (MAPP) treated composite as compared to the untreated one. The tensile strength and tensile modulus of MAPP treated composite was found to be 29.24 MPa and 1330 MPa, respectively, which was found to be 7.5% and 6.4% greater than that of untreated composite. The experimentally observed tensile properties of the composites were compared with the existing models of reinforced composites. The surface morphology and fiber surface treatments were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy.

Developing a Novel Hyperbranched Polymer-Modified PP/Clay Nanocomposite: Characteristics Investigation

Polypropylene, as a thermoplastic polyolefin, possesses advantageous physical, mechanical and thermal characteristics, but also suffers from disapproving lesser properties such as poor dye- and coat-ability. Herein, nanoclay particles and a polyester-amide-based hyperbranched polymer are utilized to improve paint-ability along with mechanical properties. XRD and SEM results rationalize the idea that maleic anhydride-modified polypropylene and hyperbranched polymer together improve the nanoclay dispersion. The corresponding idea of “molecular skateboards” is also developed via rheology measurements. DMA data demonstrate that mechanical characteristics of the hyperbranched polymer-modified samples remain intact or even improved comparing neat polypropylene and contact angle measurements reveal reduction in θ values.

Adhesion and Tensile Properties of a Novel Fiber-Metal Laminate Based on Polypropylene Reinforced with Aramid Fibers.

ABSTRACTThe aim of the present study is to analyze interfacial adhesion and characterize the tensile properties of a FML elaborated from thin layers of an aluminum alloy and layers of maleic anhydride modified polypropylene (MAHPP) reinforced with an aramid woven fabric. For the analysis of interfacial adhesion, a microbond test is carried out on the MAHPP-aramid fiber system and a single lap joint test is performed on FML constituent materials, as well as the tensile characterization of the FML and its constituents is conducted accordingly. Microbond testing revealed an improvement in interfacial shear strength for the MAHPP-aramid fiber system in comparison with that of polypropylene-aramid fiber systems reported in the literature. The apparent shear strength between the FML constituent materials is comparable to that for bonding of aluminum with MAHPP. Tensile characterization of the FML and its constituents showed that the FML presented greater tensile strength than the aluminum alloy; and a more ductile behavior in comparison with its individual components due to the degree of adhesion between the constituents which allows the material to deform in unison.

Effect of Crystallinity on Mechanical Properties of Carbon Fiber Reinforced Polypropylene

In this study, effect of crystallinity on mechanical properties of carbon fiber reinforced thermoplastics (CFRTP) was investigated. Polypropylene (PP) and maleic anhydride modified polypropylene (MAPP) were used as matrix. The crystallinity of PP was controlled by using heat treatment after hot press molding of CFRTP. The range of crystallinity of PP and MAPP were from 26% to 40%. Flexural tests and izod impact tests of CFRTP were conducted based on Japanese Industrial Standard (JIS) K 7074 and JIS K 7110, respectively. As a result, flexural property and izod impact value of CFRTP using PP increased with an increase of crystallinity. However, flexural property and izod impact value of CFRTP using MAPP almost did not change with an increase of crystallinity.

Mechanical Properties of Polypropylene Based Composites Reinforced with B<sub>4</sub>C

The present work aims to compare the mechanical properties of Polypropylene (PP) based composites reinforced with B4C. Maleic Anhydride Modified Polypropylene (MAPP) was added to improve the B4C-matrix interphase. Processing has been carried out by twin-screw extrusion and injection molding. By adding the B4C particles to the PP and PP+MAPP matrix, the yield strength, shore D hardness, microhardness and relative scratch resistance increased gradually, but PP+MAPP/B4C composites showed better overall mechanical properties than the PP/B4C composites. However, elongation at break values occurred for all composites dropped with the B4C content, and PP+MAPP/B4C composites exhibited lower elongations at break than PP/B4C composites.

Malaysian university studies use of powdered kenaf as a reinforcing filler

In Malaysia, researchers from the Universiti Teknologi MARA (UiTM) have been studying the suitability of ground kenaf core as a reinforcing filler for wood–plastic composites (WPCs). Using the powdered material in combination with maleic-anhydride-modified polypropylene (MAPP) as the coupling agent, the team claim to have created a new, more-durable WPC.

Synthesis of Polyolefin-g-Poly(ethylene oxide) by Reacting Maleic Anhydride Modified Polypropylene or Poly(propylene-co-ethylene) with Hydroxy-terminated Poly(ethylene Oxide) in the Melt

The synthesis of amphipolar graft copolymers by reactive extrusion of maleic anhydride modified polypropylene or poly(propylene-co-ethylene) and α, ω-dihydroxy-poly(ethylene oxide) or α-hydro-ω-oxymethyl-poly(oxyethylene) was studied. The graft copolymers were characterized by Fourier transform infrared spectroscopy. Residence time of 30 min at 160°C was established to be sufficient for graft copolymer formation by melt extrusion.

Synthesis of Hyperbranched Polypropylene/Organoclay Nanocomposites by Metal Catalyzed Living Radical Polymerization and Solvent Blending Method

Isotactic polypropylene-based polymer hybrids linking poly methyl methacrylate was successfully synthesized by a graft copolymerization from maleic anhydride-modified polypropylene (MAH-graft-PP). MAH-graft-PP reacted with ethanolamine to produce a hydroxyl group containing polypropylene (PP-OH) and obtained PP-OH was treated with α-phenyl chloroacetyl chloride and converted to a chloroacetyl group containing polypropylene (PP-Cl). The metal-catalyzed radical polymerization of MMA with PP-Cl was performed using a copper catalyst system in xylene solution at 100°C to give the PP-based polymer hybrids linking PMMA segments (PMMA-graft-MAH-graft-PP). Finally the grafted copolymer/MMt nanocomposite prepared by solution intercalation method.

Well-defined poly(methyl methacrylate) grafted to isotactic polypropylene by metal-catalyzed living radical polymerization

Isotactic polypropylene-based polymer hybrids linking poly(methyl methacrylate) (PMMA) was successfully synthesized by a graft copolymerization from maleic anhydride-modified polypropylene (PP; PP-MAH). PP-MAH reacted with ethanolamine to produce a hydroxyl group containing PP (PP-OH), and thus, the obtained PP-OH was treated with α-phenyl chloroacetyl chloride and converted to a chloroacetyl group containing PP. The metal-catalyzed radical polymerization of methyl methacrylate with PP-Cl was performed using a copper catalyst system in o-xylene solution at 100°C to give the PP-based polymer hybrids linking PMMA segments (PP-PMMA hybrids). Thus, obtained PP-PMMA hybrids demonstrated higher melting temperature than PP-Cl and microphase-separation morphology at the nanometer level owing to the chemical linkage between both the segments. The prepared graft copolymer was characterized by Fourier transform infrared and 1H nuclear magnetic resonance techniques. Glass transition temperature of grafted copolymer was investigated using thermogravimetric analysis and differential scanning calorimetric techniques.

Isolation and characterization of betel nut leaf fiber: Its potential application in making composites

AbstractBetel nut leaf fiber (BNLF) is a new finding as cellulosic filler for polymer composites. Its main constituents are 75% α‐cellulose, 12% hemicelluloses, 10% lignin, and 3% others matter, viscosity average molecular weight 132,000 and degree of crystallinity 70%. In the present work, BNLF reinforced polypropylene (PP) composites were prepared using heat press molding method. 5–20 wt% short length fiber is taken for getting benefits of easy manufacturing and the fiber was chemically treated with NaOH, dicumyl peroxide (DCP), and maleic anhydride‐modified PP (MAPP) to promote the interfacial bond with PP. The extent of modification of fiber was assessed on the basis of morphology, bulk density, moisture absorption, thermal, and mechanical properties of untreated fiber, treated fiber, and their reinforcing PP composites. The tensile and flexural strength of composites increase with the increase of fiber loading up to 10 and 20 wt%, respectively. It was also observed that Young's modulus and flexural modulus increase with fiber loading. The thermal degradation behavior of resulting composites was investigated. Among the various treated fibers, MAPP‐treated fiber composite showed best interfacial interactions as well as mechanical and thermal properties. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers