Addition Of Anhydride Research Articles

The Effect of Glycerol, Sugar, and Maleic Anhydride on Pectin-Cellulose Thin Films Prepared from Orange Waste.

This study was conducted to improve the properties of thin films prepared from orange waste by the solution casting method. The main focus was the elimination of holes in the film structure by establishing better cohesion between the major cellulosic and pectin fractions. For this, a previously developed method was improved first by the addition of sugar to promote pectin gelling, then by the addition of maleic anhydride. Principally, maleic anhydride was introduced to the films to induce cross-linking within the film structure. The effects of concentrations of sugar and glycerol as plasticizers and maleic anhydride as a cross-linking agent on the film characteristics were studied. Maleic anhydride improved the structure, resulting in a uniform film, and morphology studies showed better adhesion between components. However, it did not act as a cross-linking agent, but rather as a compatibilizer. The middle level (0.78%) of maleic anhydride content resulted in the highest tensile strength (26.65 ± 3.20 MPa) at low (7%) glycerol and high (14%) sugar levels and the highest elongation (28.48% ± 4.34%) at high sugar and glycerol levels. To achieve a uniform film surface with no holes present, only the lowest (0.39%) level of maleic anhydride was necessary.

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.

Fabrication and Characterization of Polyethylene Nanocomposite Films Containing Zinc Oxide (ZnO) Nanoparticles Synthesized by a Cost-Effective and Safe Method

ZnO nanoparticles were synthesized through a cost-effective and safe method followed by fabrication and characterization of polyethylene/ZnO nanocomposite films and investigation of their properties. The morphology and size of the synthesized nanoparticles were evaluated by field emission scanning electron microscopy (FE-SEM). It was found that nanoparticles with a plate-like morphology with an average thickness of 50-70 nm were synthesized. The nanocomposites were characterized by using Fourier transform infrared analysis (FTIR) and ultraviolet–visible spectroscopy (UV-VIS). In addition, the effects of the amount of zinc oxide nanoparticles (ZnO-NPs) on the mechanical properties of the films and particles and their antibacterial properties against a gram-negative bacterium (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus) were investigated. In the case of nanoparticles, one more gram-positive bacterium (Staphylococcus aureus) was studied. The results demonstrated an inhibition of growth of all bacteria in a broth medium for both the nanoparticles and nanocomposites. The FE-SEM micrographs revealed that by increasing the nanofiller content an inferior quality of dispersion was obtained which was reflected in the lower tensile strength of the nanocomposites compared to the pure PE. It was demonstrated that the addition of poly ethylene graft maleic anhydride (PE-g-MA), as compatibiliser, improved the dispersion state of the nanoparticles and, consequently, the ultimate mechanical properties. In addition, it was shown that the fabricated nanocomposites exhibited considerable UV-shielding properties.

Mechanical and flow properties of blends of polypropylene and powder coating recyclates with and without addition of maleic anhydride

AbstractIn this research, from 10% to 40% by weight of hydrolyzed powder coating recyclates were used as filler in polypropylene (PP). Firstly, PP and filler were dry‐mixed and then, in order to get a homogeneous mixture, were extruded at 180°C. The resulting compounds were cooled and granulated, and by use of an injection molding machine at 180–200°C, standard tensile test bars were produced. Tensile stress, three‐point bending strength, and izod impact strength of these specimens containing different types of filler and different filler concentrations were tested. The results are presented, and the effects of type and content of hydrolyzed powder coating waste on the mechanical properties of polypropylene are discussed. Also, the change in melt flow index of polypropylene as a function of filler content is analyzed. Furthermore, the bonding mechanism of filler and matrix material was examined by electron microscopy.

Use of Recycled Pulped Chromated Copper Arsenate-Treated Wood Fibre in Polymer Composites

The goal of this study was to investigate if it is possible to recycle chromated copper arsenate (CCA)-treated wood for use in wood polymer composites. This was done by soda pulping wood chips of CCA-treated lumber in a laboratory-scale digester. Composites of 10–30 weight percentage of filler in polypropylene were produced with and without the addition of maleic anhydride grafted polypropylene (MAPP) as a coupling agent. These composites were produced using extrusion compounding and injection moulding. The mechanical properties were determined using tensile testing; the properties examined in this study are the ultimate tensile strength, Young’s modulus and strain at break. The effect of the CCA-treated filler on the dimensional stability was investigated by comparing the moisture absorption with virgin wood-filled composites. It was found that ultimate tensile strength improves with increasing filler percentage for the compositions with MAPP. The Young’s modulus increases with increasing filler percentage for all compositions, and failure strain decreases with increasing filler percentage for all compositions. Moisture absorption studies show that the moisture absorption decreases when MAPP is added to the composite, and a slight decrease in moisture uptake is observed for the CCA-treated wood composites with respect to the virgin wood composites.

Isolation of Artonin E from the root bark of Artocarpus rigida, synthesis of Artonin E acetate and evaluation of anticancer activity

Artonin E was isolated from the root bark of A. rigida. The isolated compound was then esterified using a known procedure by the addition of acetic anhydride with pyridine catalyst. The structure of the synthesized compound was carefully determined by physical and spectroscopic techniques and compared to the data in the literature. The anticancer activity test against murine leukemia cancer cells P-388 showed that the ester compound has good activity with an IC50 of 2.79 μg/mL and much better stability during storage compared to Artonin E itself.

Functionalization of Chitosan with Maleic Anhydride for Proton Exchange Membrane

Chitosan was modified by maleic anhydride, and it was then functionalized using heterogeneous and blending method to obtain the membrane. The results of the reaction between chitosan with maleic anhydride were signed by the new peak appears around 1475 cm-1 which attributed to C=C bending of alkene. The new peak also appears at 1590 cm-1 which attributed to N-H bending of amide. Chitosan-maleic anhydride membranes show microstructure of chitosan membrane with high porous density and rigidity while chitosan-maleic anhydride membranes have clusters. In addition, the thermal tenacity of membranes reached 500 °C. Modified membrane by heterogeneous and blending method have higher water uptake, ion exchange capacity, and proton conductivity than chitosan membrane. Moreover, the blending method is much more effective than the heterogeneous method that can be exhibited from ion exchange capacity and proton conductivity values of 1.08–6.38 meq g-1 and 1x10-3–1x10-2 S cm-1, 0.92–2.27 meq g-1 and 1.53x10-4–3.04x10-3 S cm-1, respectively. The results imply that modification of chitosan membrane with the addition of maleic anhydride using heterogeneous and blending method can be applied to proton exchange membrane.

Rotational Molded Maple/Hemp Fiber-Reinforced LLDPE Hybrid Composites: Morphological and Mechanical Properties

Background: Rotational molding is still a growing sector of the general polymer production. But to further improve this process, the design and production of new products with better properties must be performed. For this reason, the development of polymer composites is of interest, especially when natural fibers are used. In this case, the addition of rigid particles leads to higher mechanical properties compared to the base matrix. Unfortunately, very limited information on the production of rotomolded composites can be found in the literature. Objective: To develop rotomolded hybrid composites based on natural fibers (hemp and maple wood) in a thermoplastic resin (linear low density polyethylene). Method: The mechanical properties of the final parts were measured as a function of fiber concentration, size, ratio and surface treatment via maleic anhydride addition in solution. Results: The optimum processing conditions (rotational speed, oven temperature, and cycle time) and composition were obtained for the materials studied. The production of hybrid composites was also investigated by using a blend of both fibers with different sizes to further improve the properties of the rotomolded parts. Conclusion: The best results were obtained at 20% wt. when a 75/25 ratio of maple/hemp fibers was used. The tensile modulus and strength increased by 63 and 17% respectively compared to the matrix. Also, the impact strength was improved by 16% at 27.5% wt. when a 75/25 ratio of maple/hemp fibers was used compared to untreated fibers. Keywords: Hemp, hybrid composites, LLDPE, maple, rotomolding, surface treatment.

Organogel Polymers from 10-Undecenoic Acid and Poly(vinyl acetate)

Organogels are used in a variety of high value applications including the removal of toxic solvents from aqueous environments and the time-controlled release of compounds. One of the most promising gelators is a polyvinyl polymer containing medium chain length carboxylic acids. The existing production of this product requires synthesis of vinyl esters containing medium length carboxylic chains. This starting material must be made from an expensive and low yielding transvinylation reaction, which leaves production of useful vinyl esters and, as a result, the organogels themselves, outside the realm of practical chemistry. We have developed a new, more practical production process and used it to directly synthesize a new polymer. This new process utilizes commercially available polyvinyl acetate and accomplishes the transformation with simple hydrolysis and anhydride addition steps. The new polymers form organogels with chloroform, acetone or toluene with swell ratios up to 30. They also show time-controlled release of crystal violet over a 100 h span. This new production process opens the possibility of producing organogels utilizing agricultural resources.

Effect of nature and extent of functional group modification on properties of thermosets from methacrylated epoxidized sucrose soyate

A study was carried out to evaluate the impact of modification of epoxidized sucrose soyate using a combination of methacrylate and inert esters (acetate propionate, butyrate) on the properties of the resins as well as the thermosets. Previous studies have shown that methacrylated epoxidized sucrose soyate (MESS) can yield thermosets having high glass transition temperature (Tg) and good mechanical properties, but had high resin viscosity due to hydrogen bonding of the hydroxyl groups. Further functionalization to yield dimethacrylated epoxidized sucrose soyate (DMESS) resulted in reduced resin viscosity, but some of the thermosets were brittle. In this study, to maintain low resin viscosity and improve thermoset ductility, replacement of some methacrylate groups with various ester groups was explored. The synthesis of these resins was carried out in a one-pot process involving the sequential slow addition of anhydrides of the acids mixed prior to addition. The synthesized resins were characterized for their viscosity with and without styrene diluent. Formulations were made using varying amounts of styrene and free-radically cured using peroxyesters as initiators. The bio-based resins with 30% styrene gave much lower viscosities compared to commercial resins containing higher amounts of styrene (33% and 45%). The thermosets produced had improved flexibility and toughness with only a slight reduction in the glass transition temperature. The inclusion of the non-functional esters in the resin structure acted as internal plasticizers for the polymer system. The new sets of thermomechanical properties demonstrated the tunability of the bio-based resin system and opens up different avenues for end-use applications.

A molecular modeling study for miscibility of polyimide/polythene mixing systems with/without compatibilizer

Abstract Molecular models were established to predict the miscibility of polyimide/polythene mixing systems and the enhancing effects of compatibilizer addition of maleic anhydride grafted polythene (MAH-g-PE). Molecular dynamics simulations were applied to investigate radial distribution functions and Flory-Huggins parameters of the mixing systems. Results show that polyimide/polythene is miscible to a certain degree, and the miscibility gets better after adding MAH-g-PE. Dissipative particle dynamics (DPD) simulations display that micro-phase separation occurs in the polyimide/polythene mixing systems, however, effective interfaces appear between polyimide and polythene phases after adding MAH-g-PE. The results of molecular mechanics simulations indicate that the ability of mixing systems to resist stretch, compression and shear deformation increases after adding MAH-g-PE. This work offers a promising technique to predict miscibility properties for polyimide/polythene system prior to actual production and attempt to find a suitable compatibilizer for that system.

Influence of coupling agents on rheological, thermal expansion and morphological properties of recycled poypropylene wood flour composites

In this work, thermal expansion and morphological properties of recycled polypropylene wood flour composites were evaluated in order to verify the effect caused by the usage of a natural oil as coupling agent. The natural oil used as coupling agent was octanoic acid (C8), maleic anhydride grafted polypropylene (MAPP), widely used in industry but from non-renewable source, was also used for comparison. Composites were obtained by twin screw extrusion and injection molded. The results showed that the addition of octanoic acid and maleic anhydride grafted polypropylene reduced the coefficient of thermal expansion of the composites. The dependence of melt viscosity obeyed the Arrhenius-Eyring expression, and the activation energy values for composite viscous flow were higher than matrix. The composite morphology revels that octanoic acid promotes strong interfacial adhesion between filler and matrix, similar to that observed when maleic anhydride grafted polypropylene were used. Octanoic acid showed similar results when compared with maleic anhydride grafted polypropylene in all properties evaluated, indicating that can be used as an alternative instead of use coupling agent from non-renewable sources.

High performance bio-based thermosets from dimethacrylated epoxidized sucrose soyate (DMESS)

To tune the properties and reduce the viscosity of methacrylate functional epoxidized sucrose soyate (MESS), the use of a dual functionalization strategy was explored. Bio-based thermosets have previously been produced from free-radical curing of MESS having a large number of functional groups and have demonstrated a high glass transition temperature (Tg) and good mechanical properties. However, the MESS viscosity was high. To reduce the MESS viscosity, further functionalization of MESS was carried out by sequential addition of methacrylic anhydride. The synthesis was optimized and the resulting dimethacrylated epoxidized sucrose soyate (DMESS) was characterized using Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy (1H NMR), gel permeation chromatography (GPC), and viscosity measurements. A series of DMESS with varying range of degrees of methacrylation was synthesized. The synthesized DMESS series were combined with varying amounts of styrene diluent and cured using a free radical process with peroxyesters as initiators. The extent of cure was determined by gel content using Soxhlet extraction and confirmed using FTIR. The thermal and mechanical properties were evaluated using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and tensile testing.

Influence of Impact Modifier–Coupling agent Combination on Mechanical Properties of Wood Flour–Reinforced Polypropylene Composit

The tensile properties and impact strength of wood flour-polypropylene composite with or without impact modifier and coupling agent have been investigated. The addition of maleic anhydride and dicumyl peroxide improved the tensile properties and impact strength. With increasing ethylene–propylene rubber (EPR) and maleic anhydride (MAH)–modified ethylene–propylene rubber (MEPR), impact strength were increased, whereas tensile strength and Young’s modulus were decreased. At the same EPR or MEPR content, the higher filler loadings resulted in higher Young’s modulus and lower impact strength. Tensile properties and impact strength were greatly improved by adding EPR combined with maleic anhydride–grafted polypropylene (MAPP) and dihydroquinoline.

Synthesis and olfactory evaluation of (8S)‐(−)‐p‐Mentha‐1,3‐dien‐9‐ol and some of its esters

Abstract(8S)‐(−)‐p‐Mentha‐1,3‐dien‐9‐ol (3) has been synthesized and fully characterized, using dill ether as the starting material. Dill ether is a common constituent of the essential oil of dill weed, Anethum graveolens L. In the first step, (8S)‐(−)‐p‐mentha‐1,3‐dien‐9‐yl acetate was prepared by treating dill ether with anhydrous magnesium bromide, followed by the addition of acetic anhydride. Hydrolysis of this mixture with potassium hydroxide led to the formation of alcohol 3, with p‐cymen‐9‐ol as the main by‐product. The chemical identity of compound 3 has been confirmed by GC/MS, IR, one‐ and two‐dimensional NMR. Chiral analysis has shown that it consists of enantiomerically pure (8S)‐(−)‐p‐mentha‐1,3‐dien‐9‐ol. This has been corroborated by selective oxidation of p‐mentha‐1,3,8‐triene found in the essential oil of curly leaf parsley, Petroselinum crispum (Mill.) Fuss., to give a racemic mixture of p‐mentha‐1,3‐dien‐9‐ol. Other esters (propionate, butyrate and valerate) of alcohol 3 have been prepared in a similar way by treating dill ether with the corresponding acid anhydride. Olfactory evaluation of alcohol 3 revealed a floral character while its esters gave a range of fruity and herbaceous notes.

Zeolite A‐polypropylene and silver‐zeolite A‐polypropylene composite films for antibacterial and breathable applications

ABSTRACTPolypropylene (PP) composite films were successfully prepared using melt blending by directly mixing PP pellets with zeolite A or silver‐zeolite A powder and then blowing. All the prepared films were characterized in terms of their physical, mechanical, optical, and gas permeability properties. The structure of each composite film was similar to that of the pure PP film. The crystallinity and glossy quality of the composite films were increased by the addition of silver, zeolite, and maleic anhydride grafted PP (PP‐g‐MA). The composite PP film with zeolite A and PP‐g‐MA exhibited a level of oxygen and carbon dioxide permeation (6438 and 15,087 cc m−2 day−1 atm−1, respectively). Finally, all the films were evaluated for their antibacterial activity and fruit packaging applications. Silver‐zeolite A‐PP composite films exhibited a bactericidal activity of 79% against Staphylococcus aureus and 52% against Escherichia coli, while the zeolite A‐PP film could extend the shelf‐life of bananas for over a week. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45450.

Analisis sifat fisika pemanfaatan pati tandan kosong sawit dan limbah plastik LDPE sebagai bahan pembuatan plastik biodegradabel

This research aimed to overcome the issue of plastic packaging waste that accumulates in nature because synthetic polymers cannot be easily unraveled by bacteria. Biodegradable plastics were produced by mixing waste of plastics of the low density polyethylene (LDPE) with starch of empty palm fruit bunches, modified with the addition of maleic anhydride as a crosslinking agent. To produce biodegradable plastics, different compositions of LDPE waste, starch of empty palm fruit bunch, maleic anhydride, and benzoyl peroxide were used, namely (90: 10: 1: 1), (80: 20: 1: 1), (70: 30: 1: 1), and (60: 40: 1: 1). Research stages consisted of extraction of starch from palm empty fruit bunch (PEFB); preparation of biodegradable plastic powder with the reflux method and xylene solvents; and making of biodegradable plastics using the press molding method. Based on the results of characterization, it was revealed that the optimum condition was generated by biodegradable plastics with the composition of LDPE waste, starch of empty palm bunches, maleic anhydride, and benzoyl peroxide was equal to 60: 40: 1: 1, which generated the tensile strength value of 6.9410 N/m2, the elongation at break of 3.1875%, the the melting point temperature of 103oC, and the decomposition temperature of 384oC. Besides, the thermal gravimetric test generated a residue of 12.6% and results of the analysis on morphological properties suggested that the starch distributed evenly. Keywords: Biodegradable plastics, LDPE waste, LDPE-g-MA, starch, palm empty fruit bunch.

Sustainable Biocomposites from Pyrolyzed Grass and Toughened Polypropylene: Structure-Property Relationships.

A novel class of injection-molded, toughened biocomposites was engineered from pyrolyzed miscanthus-based biocarbon, poly(octene ethylene) elastomer, and polypropylene (PP). The elastomer and biocarbon were added to the PP matrix at 30 and 20 wt %, respectively. The particle size of the biocarbon varied within two main ranges: <20 and 106–125 μm. The morphology and adhesion between the filler and the matrix were controlled by the addition of maleic anhydride grafted PP (MAPP). The composites were melt-blended and then injection-molded to tensile, flexural, and impact bars. The results showed that although the morphology of the composite is almost independent of particle size it is greatly dependent on the addition of MAPP. Two completely different morphologies, separate dispersion and encapsulated filler particles, were obtained in the presence and absence of MAPP, which was verified by atomic force and scanning electron microscopies. Model calculations based on a modified Kerner equation showed that the encapsulated filler content decreased from 64 to 8% by the addition of MAPP, which caused a major improvement in the stiffness and strength of the composites. Despite having a different morphology caused by the compatibilizer, composites with smaller particles exhibited better strength and modulus and lower impact toughness compared to those with a larger particle size. Results suggest that the failure mechanisms are mainly controlled by the local fracturing of biocarbon particles, which was more pronounced when the particle size was larger.

Recycling of waste artificial marble powder in HDPE‐wood composites

Waste artificial marble powder (AMP), an industrial waste generated from artificial marble processing, was recycled and incorporated in high‐density polyethylene (HDPE)‐wood composites. The results showed that waste AMP was mainly made up of aluminum hydroxide (Al(OH)3) and unsaturated polyester. Incorporating waste AMP into HDPE‐wood composites could increase the flexural strength and flexural modulus of composites but obviously decrease the notched impact strength. However, with the addition of maleic anhydride grafted polyethylene (MAPE), the mechanical properties of AMP/HDPE‐wood composites increased greatly. With 60 phr (parts per hundreds of resin) waste AMP, the notched impact strength and tensile strength of composites reached to 5.03 kJ/m2 and 28.0 MPa, respectively, increased by 98.1% and 55.6% compared to the composites without MAPE. Scanning electron microscopy (SEM) photographs revealed that MAPE improved the interfacial adhesion between fillers and HDPE matrix. In addition, the incorporation of waste AMP increased the heat resistance, limiting oxygen index (LOI) value of composites and decreased the horizontal burning rate. This study provides a new method for resource utilization of waste AMP, which could improve the performances of composites and avoid environmental pollution. POLYM. COMPOS., 39:2347–2355, 2018. © 2016 Society of Plastics Engineers

Flax and its thermoplastic biocomposites

The potential of flax fabric in the production of ‘green’ composites based on polypropylene (PP) was evaluated. The laminate composites were prepared by compression molding of flax fabric (with and without treatment) and PP films (using different formulations of PP). The morphology and crystallization of the PP/flax composites were characterized using scanning electron microscope, X-ray diffraction, and differential scanning calorimetry. The mechanical performance of the composites was also evaluated. The results demonstrate that fiber treatment and PP formulation play important roles on the performance of composites. This study proved that the addition of the coupling agent maleic anhydride grafted PP to the composites improves the interfacial adhesion between hydrophilic flax fibers and the hydrophobic PP matrix and thus the mechanical properties. The combination of the coupling agent and reactive additive provides superior strength, modulus and brings further fire resistance to the PP/flax composites.