Maleic Anhydride Content Research Articles

Enzymatic Synthesis and Crosslinking of Novel High Molecular Weight Polyepoxyricinoleate

Methyl epoxyricinoleate was prepared in high yield by the lipase-catalyzed epoxidation of methyl ricinoleate with H2O2. A high molecular weight polyepoxyricinoleate (PER) with a maximum weight average molecular weight (Mw) of 272,000 was enzymatically prepared by the polycondensation of methyl epoxyricinoleate using immobilized lipase from Burkholderia cepacia (lipase PS-IM) in bulk at 80 °C for 5 d. PER showed good low temperature fluidability. PER was readily cured by maleic anhydride (MA) at 80 °C to produce a chloroform-insoluble PER-MA film. Both the glass transition temperature and Young’s modulus increased with increasing MA content and PER Mw. In contrast, the elongation at break decreased with increasing MA content and PER Mw. Methyl epoxyricinoleate, PER and PER-MA showed biodegradability by activated sludge, and that of the PER-MA film decreased with increasing MA content.

Effect of compatibilizing agents on the mechanical property of rice husk flour as nano-potential filler in polypropylene biocomposite

In this article, rice husk flour filler/polypropylene (RH/PP) composites with different ratios of the filler were prepared without and with maleated PP, which was used as a compatibilizer. The RH filler in the RH/PP composites was treated with acid and alkali, and their mechanical properties were measured. The mechanical properties were improved with the addition of the compatibilizer. In this study, grafting of maleic anhydride (MA) onto PP with different ratios of benzoyl peroxide (BPO) and MA was prepared. Infrared analysis showed characteristic bands at 1786 and 1863 cm−1 for the grafted sample (maleated PP). Also, from chemical titration, the optimum MA and BPO contents were 4 and 1 part per hundred parts (php of polymer), respectively. The results showed that the morphology of the grafted sample was a flat with coarse surface, and that of the composite clearly elucidated that the interfacial bonding between RH and PP was enhanced by the presence of the compatibilizer. Thermal stability of the grafted PP was enhanced by the grafting process. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Physical properties of polymer composite: Natural rubber glove waste/polystyrene foam waste/cellulose

The polymer composite was prepared from the wastes of natural rubber glove (NRG) and polystyrene foam (PSF) blended with cellulose from sugar cane leaves via the laminate method. The NRG and PSF were firstly dispersed in toluene under continuous stirring. Then, maleic anhydride (MA) was added into the mixture. Effects of blend ratio and of MA content (0.5–15%, w/w) on physical properties of the polymer composite were investigated. The toluene resistance of the polymer blend was improved after adding MA and cellulose. The highest toluene resistance was achieved when using 12% cellulose. The chemical reactions of MA with polymer blend and with composite were confirmed by ATR-FTIR. The hardness of the polymer blend and composite increased as a function of PSF. In addition, their impact strength increased with increasing NRG and cellulose contents.

Effects of compatibilizer and nanolayered silicate on physical and mechanical properties of PP/bagasse composites

Bagasse, an agricultural waste, was investigated for wood plastic nanocomposite production. The incorporation of nanolayered silicate has been considered in recent years for improving the properties of thermoplastic composite. In this study a composite of polypropylene (PP) and bagasse fiber (BF), with different concentrations of nanoclay and maleic anhydride (MA) as compatibilizer, were fabricated by injection molding. Then physical and mechanical properties of the composites were tested according to ASTM standards. The results indicated that tensile modulus and flexural strength increased with an increase in clay loading; however, impact strength and water absorption decreased with an increase in nanolayered silicates. The degree of nanoclay dispersion in PP/BF composite was characterized by X-ray diffraction (XRD) method. The morphological study showed that the intercalation morphology in nanocomposite samples and d-spacing of layers increased with an increase in clay content. The effect of compatibilizer was positive in terms of enhancing the properties of composites. The maximum physical and mechanical properties of samples were achieved with 3% nanolayered silicates and 2% coupling agent.

Preparation of EPR/silica filler by a co-irradiation method forming PP/EPR/silica nanocomposites

This paper presents a novel approach to prepare ethylene-propylene rubber (EPR)/silica filler by co-irradiation method forming polypropylene (PP)/EPR/silica nanocomposites. The grafting of maleic anhydride (MAH) on EPR was first studied by co-irradiation in the micro-suspension without any chemical initiator, and the effects of MAH concentration and the total co-irradiation dose on the graft degree of MAH were investigated. Then PP/EPR/silica nanocomposites were successfully prepared by blending of PP matrix and EPR/silica filler, which was obtained by co-irradiation using a mixture of EPR/MAH microsuspension in xylene and tetraethoxysilane/KH560 sol in formic acid. FTIR and SEM results showed that the reactions between MAH on EPR chains and KH560 surrounding silica particles were adopted to form the EPR/silica filler with strong bonding and well silica dispersion. Mechanical properties of PP/EPR/silica nanocomposites with different silica contents and the comparisons with PP, PP/EPR and PP/silica films were studied. The rigid silica particles were trapped in EPR shell and well dispersed in PP/EPR/silica nanocomposites with good compatibility and strong interfacial adhesion, achieving overall improvements in stiffness, strength and toughness compared with pure PP.

Ultrasound initiated maleic anhydride grafted onto a novel polypropylene copolymer

AbstractThe reaction of maleic anhydride (MAH) grafted onto propylene‐based copolymer (DP) without adding any initiator was conducted through ultrasound assisted extrusion in this article. The effects of ultrasound power, die temperature, and MAH content on the grafting degree and efficiency were studied. With increasing ultrasound power, the grafting degree and efficiency of DP‐g‐MAH increase. The presence of ultrasound with higher power and lower die temperature is beneficial to increase the grafting degree and efficiency. The increase of MAH content can increase the grafting degree but reduce the grafting efficiency. Based on the results of melt flow index, dynamical rheological, gel permeation chromatograph (GPC), and Fourier transform infrared spectroscopy (FTIR) tests, the mechanisms of the grafting reaction were proposed. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers

Grafting of maleic anhydride on poly(L-lactic acid). Effects on physical and mechanical properties

Maleic Anhydride (MAH) was grafted onto poly(L-lactic acid) (PLLA) in the presence of dicumyl peroxide (DCP) as a radical initiator. The effect of the MAH and DCP concentrations on the grafting and the physical and mechanical properties of PLLA films were investigated. The glass transition temperature and crystallinity significantly decreased with addition of MAH. The thermal decomposition of the PLLA films was affected by the MAH content while the mechanical properties were almost unchanged. A slight increase in molecular weight was found, which could be attributed to either the MAH branching reaction or a possible crosslinking reaction between the PLLA chains increasing the chain entanglements.

The effect of maleic anhydride grafting efficiency on the flexural properties of polyethylene composites

AbstractMany authors have reported on the property enhancements possible by compounding high density polyethylene (HDPE) with fillers to produce composites. It is accepted that polyethylene combined with materials such as nanoclay or wood flour will not yield favorable properties unless a compatibilizing material is used to form a link. In this work, compatibilized HDPE was produced by grafting maleic anhydride (MA) to its backbone in a twin screw extruder using a peroxide initiated reactive process. Fourier transform infrared spectroscopy (FTIR) was used to examine the effects of varying peroxide and MA levels on the grafting percentage and it was found that a high percentage could be achieved. The gel content of each HDPE‐g‐MA batch was determined and twin bore rheometry analysis was carried out to examine the effects of crosslinking and MA grafting on the melt viscosity. These HDPE‐g‐MA compatibilizers were subsequently compounded with nanoclay and wood flour to produce composites. The composite materials were tested using a three point bending apparatus to determine the flexural modulus and strength and were shown to have favorable mechanical properties when compared with composites containing no compatibilizer. X‐ray diffraction (XRD) was used to examine the effects of grafted MA content on the intercalation and exfoliation levels of nanoclay composites. The results from XRD scans showed that increased intercalation in polymer nanoclay composites was achieved by increasing the grafted MA content. This was confirmed using a scanning electron microscope, where images produced showed increased levels of dispersion and reductions in nanoclay agglomerates. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Synthesis and characterization of alkali modified styrene-maleic anhydride copolymer (SMA) for dispersion of carbon black

Copolymer of styrene and maleic anhydride (MAn) were copolymerized in N, N-dimethylformamide (DMF) as a solvent and benzoylperoxide as initiator at temperature 80°C . The monomer feed ratio of styrene (Sty) and maleic anhydride (MAn) was varied in the range of 1:1 to 3:1. The acid values were about 480, 357 and 295 where as the softening temperature were 155, 140 and 120 respectively. The synthesized copolymer were hydrolyzed by various alkali viz. NaOH, KOH and NH4OH. The above synthesized copolymer and alkali modified copolymers have been characterized by 1H-NMR, DSC, TGA, SEM Optical microscopy and percentage solid settling etc. The results showed a broad overlapping peak between 1.1 and 2.3 δ ppm and peaks between 7.0 and 7.4 ppm are due to methylene/methine and aromatic ring hydrogens of styrene respectively where as Methine protons of maleic anhydride appear between 3.1 and 3.6 ppm. The Tg of copolymer were found to be greater than that of polystyrene indicating formation of a copolymer. The thermal stability of the copolymers decreased with the increase in maleic anhydride content in the copolymer. The spherical shapes of beads can be ascertained from the microphotograph for molar feed of Sty/MAn as 1:1 and these becomes irregular for 2:1 and 3:1. Where as a fine network with smaller structure as well as the well dispersed grain taken by Scanning Electron Microscopy and Optical Microscopy confirms better dispersion of carbon black when these alkali modified SMA copolymers have been added. It was also found a remarkable decrease in percentage solids when alkali modified SMA were added in the system as compared to when no resin were added. This shows the addition of SMA not only improves dispersion but also improves the stability of the system. Application of these alkali modified SMA copolymers as a dispersing agent to disperse a non- polar particles like carbon black in water were studied with the help of Daniel Flow Method and found that the sodium salts of SMA copolymers having molar feed ratio of styrene to maleic anhydride as 1:1 showed best dispersion for Carbon Black particles.

Application of Hydrolytic Styrene-Maleic Anhydride Copolymer in Denim Cellulase Washing

In order to provide the theoretical basis for the development of anti-backstaining agent. The copolymer of styrene-maleic anhydride(SMA) was synthesized by free radical solution polymerization using benzoyl peroxide(BPO) as initiator, toluene as solvent, the hydrolytic styrene-maleic anhydride copolymer (HSMA) was obtained by hydrolysis with Sodium hydroxide solution, the structure of HSMA was characterized by FI-IR. The HSMA was employed as anti-backstaining agent in the process of denim cellulase washing. The results showed that HSMA had little effect on the enzyme activity, the HSMA had excellent anti-backstaining capability, the effect of anti-backstaining increased with content of maleic anhydride in the copolymer increasing.

Thermoplasticization of High Amylose Starch by Chemical Modification Using Reactive Extrusion

Modified thermoplastic high amylose starch (MTPS) was synthesized by reactive extrusion in the presence of maleic anhydride (MA) as an esterification agent in a twin-screw extruder. The objective of this work was the preparation of reactive thermoplastic starch in the presence of glycerol and with different amounts of maleic anhydride (MA) and free-radical initiator, in order to improve processability and reactivity. The concentration of MA added varied from 2 to 6 wt% (of starch + glycerol), and the free-radical initiator, 2,5-bis(tert-butylperoxy)-2,5-dimethylhexane, also called Luperox 101, varied from 0.1 to 0.5 wt% (of starch + glycerol). Characterization of maleated thermoplastic starch was performed using dynamic light scattering and thermal analysis. Further, proof of chemically modified extrudate was determined by Fourier transform infrared spectroscopy and by soxhlet extraction with acetone. The modified high amylose corn starch (20 or 30% glycerol) could be pelletized and gave pellets that were more transparent than thermoplastic starches not modified with maleic anhydride. There was negligible change in hydrodynamic radius as the percentage of maleic anhydride increased. However, as the percentage of Luperox 101 increased, the hydrodynamic radius decreased. It could be inferred that the molecular weight decreased as the percentage of free-radical initiator increased. Using the maximum temperature in the extrusion process of 165 °C instead of 135 °C caused a decrease in the hydrodynamic radius, due to the high influence of the temperature profile on the molecular weight of the thermoplastic starch. The MTPS samples presented higher melting temperatures compared to TPS samples. The soxhlet studies indicated that the plasticizer, glycerol, was chemically linked to the starch. Using the maximum temperature of 165 °C versus 135 °C in the extrusion temperature profile resulted in more interaction between glycerol and starch.

Styrene‐assisted grafting of maleic anhydride onto isotactic poly butene‐1

AbstractGrafting of maleic anhydride (MAH) onto isotactic poly butene‐1 (iPB‐1) was carried out by thermal decomposition of dicumyl peroxide (DCP) using electron‐donating monomer styrene (St), and were carried out in the molten state in a twin‐screw extruder according to an experimental design in which the content of MAH and St were varied. The calibration curve was constructed from FTIR measurements and titration which can obtain the absolute amounts of grafted MAH according to FTIR data. The proposed mechanism was that when St is added to the iPB‐1/MAH/peroxide grafting system, St reacted first with MAH to form a charge‐transfer complex (CTC). Then CTC react (or copolymerize) with macroradicals. The grafting of MAH onto iPB‐1 (iPB‐1‐MAH) accelerated crystalline transformation rate of form II to I. The contact angle decreased with the increase of grafting degree, which indicated that surface polarity increased. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers

Poly(ethylene-co-butylene)-b-(styrene-ran-maleic anhydride)2 Compatibilizers via Nitroxide Mediated Radical Polymerization

Abstract Telechelic poly(ethylene-ran-butylene) initiator terminated with [tert-butyl[1-(diethoxyphosphoryl)-2,2-dimethylpropyl]amino] nitroxide groups (PEB-(SG1)2) was used to initiate the controlled radical copolymerization of maleic anhydride (MA) and styrene (ST). The ST/MA copolymerizations were performed in 1,4-dioxane at 110°C and resulted in PEB-b-P(ST-ran-MA)2 triblock copolymers with relatively narrow molecular weight distributions ( M ¯ m / M ¯ n ≈ 1.5 ) . Gel permeation chromatography (GPC) indicated that the initiator used was ≈93% efficient. The resulting copolymers were then blended as 20 wt.% dispersions in nylon 6 (PA6) at 230°C. With as little as 10 mol.% of MA in the feed to make the PEB-b-P(ST-ran-MA)2, blends were deemed dynamically compatibilized based on the reduced particle size. All of the PEB-b-P(ST-ran-MA)2/PA6 blends resulted in a minor phase particle size D ¯ vs = 0.1 μm while the PEB-b-P(ST)/PA6 blend had D ¯ vs = 1.15 μm (i.e. no MA in the copolymer). Tensile testing revealed yield stresses and strains decreased steadily from pure PA6 to non-reactive PEB-b-P(ST)2/PA6 to PEB-b-P(ST-ran-MA)2/PA6. However, no difference in tensile properties was observed between PEB-b-P(ST-ran-MA)2/PA6 samples made from PEB-b-P(ST-ran-MA)2 copolymer of varying MA content.

Ultrasonic induced grafting of maleic anhydride onto polypropylene in melt state

This paper presented a model study on maleic anhydride (MAH) grafted polypropylene (PP) performed in melt state through ultrasonic initiation without any chemical initiator and solvent. The structures of PP-g-MAH were characterized by FTIR and 13C NMR and the mechanism were discussed. The graft degree (G) was determined by titration using a solution of organic base tetra-butyl ammonium hydroxide (TBAOH) in ethanol, and the effects of ultrasonic intensity, MAH concentration and styrene (St) on G and graft efficiency (G E ) of MAH were investigated. Results showed that MAH was successfully grafted onto the PP chain and the optimum conditions for grafting were at an ultrasonic intensity of 300 W with a MAH concentration of 25 wt.%, and the maximum G of MAH of 3.34 wt.% was obtained when the molar ratio of St to MAH was 1:1. DSC and XRD were also employed to determine the thermodynamic performance and crystalline structures of the products.

Synthesis, characterization and use of polymer‐supported phase transfer catalyst in organic reactions

AbstractA polymer‐supported (PS) phase transfer catalyst, polyethylene‐g‐quaternary ammonium salt (PE‐g‐QN+), is prepared through a three‐step graft copolymerization of maleic anhydride (MAn) onto polyethylene (PE) by photochemical method using 1% benzophenone (Bz) as photosensitizer. Post grafted acid hydrolysis of polyethylene‐g‐maleic anhydride (PE‐g‐MAn) results in the preparation of PE‐g‐succinic acid which on further treatment with tetrabutylammonium bromide (TBAB) under basic conditions in tetrahydrofuran (THF) gives PE‐g‐QN+. Optimum conditions pertaining to maximum percentage of grafting have been evaluated as a function of concentration of maleic anhydride, amount of photosensitizer, and time of reaction. Maximum percentage of grafting (25%) was obtained using 3.57 mol of MAn and 0.5 mL of 1% Bz in 120 min. The PE and graft copolymers, PE‐g‐MAn, and PE‐g‐QN+ were characterized by FTIR Spectroscopy and thermogravimetric analysis (TGA). The ionic nature of quaternary ammonium salt, PE‐g‐QN+ has also been confirmed by conductance measurements. PE‐g‐QN+ reagent have been used successfully for polymerization, amidation, and esterification reactions. The products obtained were characterized by FTIR and H1NMR spectral methods. The reagent was reused for the further reactions and it was observed that the polymeric reagent polymerize, amidate, and esterificate the compounds successfully but with little lower product yield. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Preparation and properties of bitumen modified with the maleic anhydride grafted styrene‐butadiene‐styrene triblock copolymer

AbstractA procedure to improve the properties of styrene‐butadiene‐styrene (SBS) copolymer modified bitumen by grafting of maleic anhydride (MAH) onto SBS in the presence of benzoyl peroxide (BPO) as initiator was proposed. The effects of the grafting degree (GD) on the properties of modified bitumen were investigated. FTIR spectroscopy was employed to verify the grafting of MAH onto SBS. The GD of MAH onto SBS was determined by a back titration procedure. To assess the effects of the GD of grafted SBS on properties of modified bitumen, the softening point, penetration, ductility, elastic recovery, penetration index, viscosity, storage stability, and dynamic shear properties were tested. Experimental results indicated that the SBS grafted with maleic anhydride (SBS‐g‐MAH) copolymer was successfully synthesized by solvothermal method, and different GD of the SBS‐g‐MAH was obtained by control the MAH concentration. The GD of the MAH onto SBS has great effect on the rheological properties of the modified bitumen, and the high temperature performance and storage stability of modified bitumen were improved with the GD of the MAH onto SBS increasing. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers

Development of Maleated Starches Using an Internal Mixer

AbstractSummary: Novel maleated starches (MSt) were prepared by chemical modification of cornstarch with maleic anhydride (MA), using an internal mixer as a reactor. Benzoyl peroxide (BPO) was chosen as initiator. Physico‐chemical parameters were given by the process, recorded at different MA contents, under the same reaction conditions. Processing was carried out at 50 °C, 30 rpm for 8 min. Torque developed during processing was given by the digital display of the rheometer, and the total specific mechanical energy (SME) input was estimated. FTIR measurements confirmed the successful incorporation of MA into the starch backbone. X‐ray diffractograms obtained for the products revealed disruption of the crystalline structure of native starch. The results indicated that the MA content had a significant effect on the characteristics of the resulting modified starches.

Modification of poly(lactic acid)/poly(propylene carbonate) blends through melt compounding with maleic anhydride

Maleic anhydride (MA) is incorporated into poly(lactic acid) (PLA)/poly(propylene carbonate) (PPC) blends to modify its properties through melt compounding. It is interesting to note that the toughness of PLA/PPC blends can be improved by 1355% while the strength is almost kept constant by adding very low content (as low as 0.9%) of MA into the blends. However, higher MA content in the blends leads to decrease in strength and further increase in toughness indicating an obvious plasticizing effect, while MA is shown to have no effect on the toughness of neat PLA. Rheological, scanning electron microscopy (SEM) and dynamic mechanical analysis (DMA) studies have been carried out to understand the above results. It is believed that the improvement in mechanical performance originated from the largely retained molecular weight of PPC and improved interfacial interaction after processing. And relative large amount of MA in the blends is shown to mainly plasticize the PPC phase rather than the PLA phase. Such an effective method could provide PLA based biodegradable polymer blends with novel properties for industrial applications.

Effects of kaolin and maleic anhydride contents on melt elasticity and flexural behaviour of polypropylene/kaolin and unplasticised poly(vinyl chloride)/kaolin composites

AbstractPolypropylene/kaolin and unplasticised poly(vinyl chloride)/kaolin composites were prepared by directly melt mixing polypropylene (PP) and unplasticised poly(vinyl chloride) (UPVC) with maleic anhydride (MAH) and low cost kaolin via in situ extrusion process. The influences of kaolin particles and MAH in PP and UPVC matrix were discussed through investigating the flexural and morphological properties of filled PP and UPVC composites. The extrudates obtained from the extrusion process were carefully collected in order to investigate the elastic properties (extrudate swell and melt fracture). Results revealed that the above mentioned properties are strongly dependent on the presences of kaolin and MAH in both composite systems. Observation on scanning electron microscopy (SEM) analysis showed that the kaolin books (stacks of kaolin particles) were successfully delaminated thus lead to a well dispersed of kaolin particles in PP and UPVC matrix.

Studies on Maleated Natural Rubber/Organoclay Nanocomposites

Maleic-anhydride-grafted natural rubber prepared by gamma radiation was used for preparing natural-rubber-based nanocomposites. Modified clay (up to 7 wt.%) was used for the reinforcement. Maximum improvement in mechanical properties was observed at a filler content of 5 wt.%. The maleic anhydride concentration was varied from 1 to 5% and was found to have a significant effect on the properties of the nanocomposites. The XRD pattern shows that there is a considerable improvement in the d spacing of nanoclay with the incorporation of rubber. Exfoliated layers can be seen from TEM micrographs.