Hydroxyl Groups Of Starch Research Articles

Synthesis and physicochemical properties of carboxymethyl chestnut starch

Carboxymethyl chestnut starch (CMCS) was synthesized by the reaction of chestnut starch and monosodium chloroacetate in an alkali environment. The hydroxyl groups of starch were etherized through carboxymethyl groups, and the crystallinity of starch was reduced after carboxymethylation. As degree of substitution (DS) increased from 0.22 to 0.63, the degree of amyloglucosidase hydrolysis decreased from 37.0 to 1.6%, which was markedly lower than that of native chestnut starch (NCS) (83.2%). The differential scanning calorimetry results revealed the absence of a transition peak in all CMCS samples. CMCS paste showed significant higher light transmittance and freeze-thaw stability than those of NCS, and had no water release during storage at room temperature. CMCS with middle DS showed higher viscosity than NCS at high shear rate. The results demonstrated that CMCS can be applied in the industrial processing of paste foods and frozen food as a thickening agent. Practical applications Carboxymethylated starch can be used as an alternative thickener in a wide range of industrial applications. However, there is little information on the synthesis and physicochemical properties of carboxymethylated chestnut starch till now. In the present study, the carboxymethylated chestnut starch was synthesized by the optimization of process, and the microstructure, light transmittance, and freeze-thaw stability of starch were studied. We believe that starch industry can utilize the results of this study in the synthesis and application of this modified starch.

Effect of interactions between starch and chitosan on waxy maize starch physicochemical and digestion properties

ABSTRACTPhysicochemical and digestion properties of chitosan modified starch prepared by dry heat treatment were investigated. Starch granule aggregation occurred following the addition of chitosan and this trend was enhanced with increasing chitosan concentration. The size of chitosan modified starch particles was about six times of that of the native starch granules. Interactions between the hydroxyl groups of starch and the amino groups of chitosan was confirmed by Fourier transform infrared spectroscopy analysis. The disappearance of the trough in the Rapid Visco Analyzer profile indicated that the cross-links increased the starch shear resistance. The cross-links between starch and chitosan also reduced starch digestion rate compared to the control (p < 0.001), and this reduction was further enhanced with an increasing chitosan concentration. Additionally, the addition of chitosan altered starch digestion kinetics from one phase to two phases, implying that chitosan modification changed both starch structure and its digestion behaviors.

Thermo-responsive behavior of propynyl-containing hydroxyethyl starch

Thermo-responsive polymers present great advantages in the targeted delivery and release of drugs. In this study, a novel type of thermo-responsive polymer called 2-hydroxy-3-(2-propynyloxy) propyl hydroxyethyl starch (PyHES) was synthesized via hydrophobic modification of hydroxyl groups in hydroxyethyl starch (HES) with 2- propynylglycidyl ether (PGE). Aqueous PyHES solutions with an appropriate degree of substitution (DS) of hydrophobic propynyl groups exhibited strong thermo-responsive properties as well as a cloud point temperature (Tcp) that could be tuned within a range of 31 to 48 °C by changing the DS or PyHES concentrations. Moreover, the Tcp decreased with increases in the DS or the concentration of PyHES. The Tcp of PyHES had a linear relationship with DS, and DLS characterizations indicated that PyHES can form thermo-responsive micellar nanoparticles in aqueous solutions. In addition, PyHES can be further functionalized via click reaction of the propynyl group.

Physicochemical and Mechanical Properties of Bambara Groundnut Starch Films Modified with Stearic Acid.

The physicochemical and mechanical properties of biofilm prepared from bambara starch modified with varying concentrations of stearic acid (0%, 2.5%, 3.5%, 5%, 7%, and 10%) were studied. By scanning electron microscopy, bambara starch films modified with stearic acid (≥3.5%) showed a progressively rough surface compared to those with 2.5% stearic acid and the control. Fourier transform infrared spectroscopy spectra revealed a peak shift of approximately 31 cm-1 , suggesting the promotion of hydrogen bond formation between hydroxyl groups of starch and stearic acid. The addition of 2.5% stearic acid to bambara starch film reduced water vapor permeability by approximately 17%. Bambara starch films modified with higher concentration of stearic acid were more opaque and showed significantly high melting temperatures. However, mechanical properties of starch films were generally negatively affected by stearic acid. Bambara starch film may be modified with 2.5% stearic acid for improved water vapor permeability and thermal stability with minimal effect on tensile strength.

Synergistic reinforcing effect of TiO2 and montmorillonite on potato starch nanocomposite films: Thermal, mechanical and barrier properties

In this study, ternary potato starch (PS) bionanocomposite films containing two types of nanoparticles, sodium montmorillonite (MMT), one-dimensional (1D) clay platelets, (3 and 5wt%) and TiO2, three-dimensional (3D) nanospheres, (0.5, 1 and 2wt%), are prepared using solvent casting method. X-ray diffraction (XRD) test confirms the completely exfoliated structure formed in the PS-MMT nanocomposites containing 3 and 5% MMT. The success of the formation of new hydrogen bonds between the hydroxyl groups of starch and nanofillers is confirmed by Fourier transform infrared (FTIR) spectroscopy. Tensile strength (TS), elongation at break (EB), glass transition temperature (Tg), and melting point (Tm) of the films are also enhanced after MMT and TiO2 incorporation. The water vapor permeability (WVP) and the visible, UVA, UVB and UVC lights transmittance decreases upon TiO2 and MMT content increasing. Generally, a synergistic effect is observed between MMT and TiO2 at lower concentrations of MMT.

Modification of physicochemical and thermal properties of starch films by incorporation of TiO2 nanoparticles

In this research, potato starch and TiO2 nanoparticles (0.5, 1 and 2wt%) films were developed. Influences of different concentrations of TiO2 on the functional properties of nanocomposite films (water-related properties, mechanical characteristics, and UV transmittance) were investigated. XRD, FTIR, and DSC analyses were used to characterize the morphology and thermal properties of the films. The results revealed that TiO2 nanoparticles dramatically decreased the values of water-related properties (water vapor permeability: 11–34%; water solubility: 1.88–9.26%; moisture uptake: 2.15–11.18%). Incorporation of TiO2 led to a slight increment of contact angle and tensile strength, and a decrease in elongation at break of the films. TiO2 successfully blocked more than 90% of UV light, while opacity and white index of the films were enhanced. Glass transition temperature and melting point of the films were positively affected by the addition of TiO2 nanoparticles. The result of XRD study exhibited that due to a limited agglomeration of TiO2 nanoparticles, the mean crystal size of TiO2 increased. Formation of new hydrogen bonds between the hydroxyl groups of starch and nanoparticles was confirmed by FTIR spectroscopy. In conclusion, TiO2 nanoparticles improved the functional properties of potato starch film and extended the potential for food packaging applications.

Nonedible Starch Based “Green” Thermoset Resin Obtained via Esterification Using a Green Catalyst

In this study, a biobased thermoset resin was developed from a nonedible starch source obtained from mango processing industrial waste. Mango seed starch (MSS) was extracted from defatted mango seed kernels and cross-linked using a “green” cross-linker/catalyst system, 1,2,3,4-butane tetracarboxylic acid (BTCA)/sodium propionate (NaP), to obtain the thermoset resin. The tensile properties of the cross-linked MSS were found to be adequate to replace edible starch based thermoset resins, e.g., potato or corn or proteins such as soy. The cross-linking or the esterification reaction proceeds faster and at lower temperature in the presence of a suitable catalyst. Sodium hypophosphite (SHP), a widely used catalyst for esterification using poly(carboxylic acid)s and hydroxyl groups of starch or cellulose, contains phosphorus and the effluents containing SHP, i.e., phosphorus, are toxic to humans and can adversely affect the fauna in water. Also, SHP decomposes to toxic phosphine gas when heated. The results of t...

Study of degradability and cytotoxicity of polyurethanes obtained from polyols derived from castor oil and starch modified via glycosylation with ethylene glycol

Event Abstract Back to Event Study of degradability and cytotoxicity of polyurethanes obtained from polyols derived from castor oil and starch modified via glycosylation with ethylene glycol Manuel Valero1 1 Universidad de La Sabana, Chemical engineering Program, Colombia Numerous studies have been performed using castor oil and starch in the synthesis of polyurethanes. The results have demonstrated that when the starch is added directly, without modification, the tensile strength and hardness are increased, and the elongation at break decreases. However, the changes in these properties are not significant because when unmodified starch is added, the starch hydroxyl groups do not react to form urethane bonds, and the primary effect of the starch granules is to act as strengthening filler in the material. In addition, it has been found that the separation of phases increases because of the contrast between the hydrophilic nature of the starch and the hydrophobic nature of the polyurethane. Various methods of causing the hydroxyl groups present in the starch structure to form urethane bonds, thereby improving the interfacial adhesion between the starch and the polyurethane matrix, have been evaluated. One of these methods is the modification of the starch through a glycosylation reaction. When the starch is divided into smaller units (disaccharides and monosaccharides), a polyol with greater hydroxylic functionality is obtained; therefore, it is possible to obtain polyurethane with a greater cross-linking density. In previous studies, a diverse range of polyurethanes obtained from polyols derived from castor oil (original and modified) and starch have been synthesized and characterized, but in most of these studies, diisocyanates derived through petrochemistry have been used, such as methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI) and isophorone diisocyanate (IPDI). Some aromatic diisocyanates can produce toxic and carcinogenic products, and therefore, these materials are not suitable for the manufacture of biodegradable scaffolds, whereas aliphatic diisocyanates degrade into non-toxic products. Moreover, most of these studies have focused on the synthesis and mechanical, thermal and morphological characterization of the developed materials; few studies have been concerned with the evaluation of the biodegradable and biocompatible nature of these materials in an attempt to identify candidate materials for biomedical applications. However, polyurethanes have become one of the most popular classes of biomaterials for use in biomedical applications because of their excellent mechanical properties and biocompatibility. The objective of the present study was to obtain a polyurethane that can be derived from renewable resources (castor oil and starch) using a diisocyanate (lysine methyl ester diisocyanate (LDI)) and that is easily hydrolyzed and biocompatible. Polyurethanes were synthesized from castor-oil-derived polyols, starch modified via glycosylation with ethylene glycol and lysine-derived diisocyanates. The effects of the modification of the diisocyanate structure on the mechanical and thermal properties of the materials were studied, as were the materials’ biodegradation characteristics (contact angle, swelling in water and in vitro degradation) and in vitro cytotoxicity as a function of the changes in the interactions between the soft and hard segments and in the cross-linking density of the polyurethane. The results were compared with those of homologous materials obtained in previous studies using IPDI. The objective was to evaluate biodegradable segmented polyurethanes that may be useful in biomedical applications. Keywords: in vitro, Biocompatibility, biomedical application, biodegredation Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: Poster Topic: Adhesive biomaterials Citation: Valero M (2016). Study of degradability and cytotoxicity of polyurethanes obtained from polyols derived from castor oil and starch modified via glycosylation with ethylene glycol. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.00929 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. 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Thermoreversible crosslinked thermoplastic starch

AbstractA novel furan‐modified thermoreversible crosslinked thermoplastic starch was synthesized. The crosslinking mechanism was based on a thermoreversible furan/maleimide adduct formed by the Diels − Alder reaction. Thermoplastic starch (TPS) was first modified by forming a urethane linkage between the product of the reaction of furfuryl alcohol with 4,4‐methylene diphenyldiisocyanate and a starch hydroxyl group. Crosslinking was then achieved by the addition of 1,1′‐(methylene‐di‐4,1‐phenylene) bismaleimide to the furan‐grafted starch in solution (dimethylsulfoxide) and in the molten state during conventional extrusion. The materials were characterized by Fourier transform infrared and 1H NMR spectroscopy. The thermoreversible reaction was assessed by viscosity measurement and 1H NMR, for the system in dimethylsulfoxide, and by solubility tests, hot‐pressing experiments and dynamic mechanical analysis measurements for the extruded product. The crosslinked product showed a higher storage modulus and water resistance than its non‐crosslinked counterpart, opening novel opportunities to widen the range of TPS applications. © 2015 Society of Chemical Industry

Preparation and characterization of carboxymethyl starch microgel with different crosslinking densities

Microgels synthesized with different crosslinking densities were characterized by Fourier transform infrared (FT-IR) spectroscopy, thermogravimetry analysis (TGA), swelling, and rheological analyses. The lysozyme uptake capacity of these microgels was evaluated through the effects of lysozyme concentration, pH, and ionic strength. The microgel particle size mostly ranged within 25μm to 45μm. FT-IR analysis results suggested that sodium trimetaphosphate reacted with the hydroxyl groups of carboxymethyl starch (CMS), thereby forming ester linkages. TGA data indicated that crosslinking increased the thermal stability of CMS. Swelling degree increased with increasing pH before pH 5, and then remained almost constant. However, swelling degree decreased with increasing ionic strength and crosslinking density. The microgels behaved as viscoelastic solids because the storage modulus was higher than the loss modulus over the entire frequency range of dispersions with polymer concentrations of 3% (W/W) at 25°C. The data for the uptake of lysozyme by microgels demonstrated that the protein uptake increased with increasing pH and lysozyme concentration, as well as with decreasing ionic strength and crosslinking density. The lysozyme–microgels complex was identified by CLSM, and the distribution of lysozyme in microgels with low crosslinking density was rather homogeneous.

Improving biodegradability of polyvinyl alcohol/starch blend films for packaging applications

Polyvinyl alcohol (PVA) was blended with starch (S) in presence of glacial acetic acid as crosslinking agent. The effect of blend ratio and molecular weight of PVA on the physical, thermal and mechanical properties of PVA/S blends were investigated using various techniques such as DSC, TGA, SEM, tensile strength, and solubility tests. Furthermore, biodegradability of the blend films was also studied. In addition, FTIR spectroscopy was used to check the hydrogen bonding interaction between PVA and S in the blends. The obtained results showed that the physico-mechanical properties are strongly dependent on the molecular weight and PVA content in PVA/S blends. DSC and SEM analyses of PVA/S blend showed a single glass transition temperature indicating the formation of completely miscible blends with a single phase due to the formation of hydrogen bonds between the hydroxyl groups of PVA and starch. In addition, PVA/S blend films exhibited good mechanical properties, thermal stability as compared with the pure PVA. More interestingly, the results showed enhancement in biodegradability of PVA/S blend films and particularly in moist soil, which can be exploited for manufacturing of biodegradable and environmentally friendly packaging materials at low cost. Keywords : Blends, Starch, PVA, Biodegradability, Mechanical Properties.

Hydrophobization of starch nanocrystals through esterification in green media

Starch nanocrystals (SNC) were successfully modified through esterification by using dodecenyl succinic anhydride (DDSA), 2-octen-1-ylsuccinic anhydride (OSA) and acetic anhydride (AA) in green media. The chemical modifications were confirmed using FT-IR. The esterification extent of the modified SNC was evaluated by degree of substitution (DS). The modifications imparted hydrophobic character to SNC so that the modified SNC could be dispersed in non-polar solvents such as chloroform, dichloromethane and toluene. It was found that the dispersibility of the modified SNC in non-polar solvents increased with increasing of DS and hydrophobicity of the group replacing the hydroxyl groups in starch. XRD analysis showed that the crystalline structure of SNC was preserved after the modifications.

Thermo-compression of biodegradable thermoplastic corn starch films containing chitin and chitosan

Films based on thermoplastic corn starch (TPS) and chitosan/chitin were obtained by melt-mixing and thermo-compression. Chitosan and chitin incorporation to TPS matrix induced some structural modifications due mainly to the interactions between starch hydroxyl and chitosan/chitin amino groups. Crystallinity degree of TPS films was increased with biopolymers incorporation. Enthalpy melting values for TPS–chitosan/chitin films resulted lower than those corresponding to TPS control ones. Films had homogeneous and smooth surfaces, without pores and cracks and no glycerol migration was evidenced by Scanning Electronic Microscopy. Films fracture surfaces were uniform without the presence of unmelting starch granules neither chitosan/chitin agglomerates. Films with chitosan/chitin presented higher color, UV absorption capacity and opacity than TPS films. Addition of 10 g chitosan or chitin/100 g starch decreased 35 and 56% water vapor permeability, respectively. Biopolymers addition to TPS increased tensile strength and elastic modulus, and decreased elongation at break. Starch and glycerol-rich domains where evidenced in TPS matrixes by Dynamic Mechanical Analysis. Finally, TPS–chitosan films reduced Staphylococcus aureus and Escherichia coli growth in the contact zone.

Starch grafted poly(butylene succinate) via conjugating reaction and its role on enhancing the compatibility

A single step process of grafting poly(butylene succinate) (PBS) on starch to obtain starch-g-PBS in a heterogeneous system is proposed. Starch-g-PBS is accomplished by a conjugating reaction in chloroform at room temperature between hydroxyl groups of starch and carboxylic acid terminal groups of PBS by using N-N′-dicyclohexylcarbodiimide (DCC) conjugating agent. The grafting of PBS at both primary alcohol and secondary alcohol of starch is as high as 20–30% as confirmed by 1H NMR and HMBC 2D NMR. The grafting of PBS results in a drastic changes of the crystallization as seen from the decrease in size of spherulite. The starch-g-PBS is a good compatibilizer between PBS and starch by promoting strong interfacial adhesion of the blend as evidenced from the improvement of modulus (2 times increase) and the miscibility of the blend in SEM images.

Acidic ionic liquids catalyst in homo and graft polymerization of ε-caprolactone

Biodegradable polycaprolactone was prepared by ring-opening polymerization in presence of ionic liquids as efficient, inexpensive, nontoxic, and easily handled acid catalysts. The resulting polymer exhibited good yield and inherent viscosity between 0.10 and 0.18 dL/g. The chemical structure of obtained polymer was verified by the 1H-NMR and Fourier transform infrared spectroscopy (FT-IR) spectra. In continuation, the obtained polymer was applied to improve quality level and mechanical properties and also to reduce the hydrophilic properties of the starch, so the ring-opening polymerization of e-caprolactone was investigated in the presence of starch hydroxyl groups as initiator and ionic liquid as catalyst. The obtained starch-grafted-polycaprolactone was verified by 1H-NMR, FT-IR spectra, and field emission scanning electron microscopy analysis.

The Preparation and Characterization of Starch Oxidized by Nitric Acid and its Properties of Calcium Complexing Capacity

The primary hydroxyl groups of Starch Oxidized by nitric acid to the corresponding carboxylic acids has been investigated. The structure of the Oxidized-Starch(OS) was characterized by FT-IR, 1HNMR and GPC. The predicated product was obtained from the results. Its application in calcium complexing capacity has been discussed. The calcium complexing capacity of OS may up to 119.39 mg/g. The data confirmed that the starch oxidized by nitric acid had excellent capacity of calcium complexing.

Synthesis of biodegradable thermoplastic copolymers based on starch by atom transfer radical polymerization (ATRP): Monolayer chain growth on starch

AbstractModification of starch is increasingly being studied and starch is used for applications in which synthetic polymers have traditionally been the materials of choice. In this work the surface of starch was successfully modified by the polymerization of polystyrene and polyacrylamide by atom transfer radical polymerization (ATRP) method in dispersion medium. For this propose the bromoactylated starch was prepared by the reaction between hydroxyl groups of starch and the bromoacetyl bromide in DMA/LiCl (5%) in the presence of pyridine. The bromoactylated starch acts as macroinitiator in ATRP of styrene. The polymer chains' growth on surface of starch was clearly showed by the AFM images. Other analyses were used in this work such as FT‐IR, DSC, and TGA.

Physicochemical, Microstructural, and Antibacterial Properties of β‐Chitosan and Kudzu Starch Composite Films

This study investigated physicochemical, microstructural, and antibacterial properties of β-chitosan-kudzu starch composite films with addition of 0%, 20%, 60%, or 100% kudzu starch (w starch/w chitosan) in 1% chitosan solution. Molecular interactions between chitosan and kudzu starch and the crystal structure of the films were also determined. Adding 60% kudzu starch reduced water vapor permeability and solubility of pure β-chitosan film by about 15% and 20%, respectively, whereas mechanical strength and flexibility of the film were increased about 50% and 25%, respectively. Micrograph showed that β-chitosan film was totally amorphous, and the composite films generally became rougher with more starch added. Fourier transform infrared and X-ray diffraction spectra showed that the 2 film-forming components were compatible with each other. Pure β-chitosan film resulted in 9.5 and 11.5 log CFU/mL reduction in Escherichia coli and Listeria innocua based on plate count method, respectively. Addition of kudzu starch reduced the antibacterial activity of film, but still achieved 8.3 and 10.3 log CFU/mL reduction in E. coli and L. innocua, respectively when kudzu starch to chitosan weight ratio was 1:1. Reduced antibacterial activity might attribute to the interaction of amino groups in β-chitosan with the hydroxyl groups in kudzu starch. This study demonstrated that kudzu starch effectively improved water barrier of β-chitosan film, and the composite films retained strong antibacterial ability. One percent of β-chitosan containing 60% kudzu starch (w/w chitosan) composite films possessed better mechanical and water barrier properties than pure β-chitosan films, and showed strong antibacterial activity against both Gram-positive and Gram-negative bacteria. The films may be used as wraps or coatings to prolong the shelf life of different foods or other similar applications.

Physical and thermal mechanical properties of corn starch/LDPE composites

AbstractThe potential of biodegradable polymers has long been recognized. In this work, composites of low density polyethylene (LDPE) and low density polyethylene/thermoplastic starch (LDPE/TPS) at different ratios of TPS (40%‐60% w/w) were prepared in internal mixer. Polyethylene‐grafted maleic anhydride (PE‐g‐MA) at 3 wt % was used as coupling agent. Chemical reactions between functional groups of composite components were studied and confirmed by Fourier transforms infrared (FTIR) spectroscopy. The morphology of film surfaces was studied using scanning electron microscopy. The physical, mechanical, and dynamic‐mechanical thermal analyses of LDPE/TPS composites were evaluated. The FTIR results showed transmission peak at 1642 cm−1, which is the result of chemical reaction between the hydroxyl groups of starch and anhydride groups of coupling agent. This verifies the presence of the carboxylate group due to the formation of ester bonding. The results showed that the water absorption and density of composite films increased by increasing the starch content in LDPE/TPS composites. The tensile strength and elongation at break decreased by increasing the starch level in the composites, but the young's modulus increased. The morphological studies showed that the biodegradability of composites increased by increasing the starch content and the results was confirmed by weight loss in buring the samples in wet soil during time intervals. The dynamic mechanical thermal analyzer thermograms showed that there are two relaxation temperature peaks. The amplitude of peaks increased by increasing the starch content from 40 to 60% probably due to increasing amorphous phase of composite. The starch was uniformly distributed throughout the LDPE polymer matrix and compatible and biodegradable composites were formed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Morphology and mechanical properties of PA12/plasticized starch blends prepared by high-shear extrusion

PA12/plasticized starch blends (PA12/TPS) were prepared by high-shear twin screw extruder. The morphology development and the mechanical properties of the blends were investigated as a function of the apparent shear rate. High-shear processing has proved to be an efficient method to finely disperse thermoplastic starch in polyamide 12 matrix. Blends containing TPS domains with a size at the nano-scale (Rn∼150nm) homogeneously dispersed in PA12 matrix were obtained. From a modeling point of view, the variation of the droplet radius is closer to the Wu's predictions compared to the Serpe's predictions. From the basic hypothesis of these models, it can be then assumed that compatibilization between both phases occurs during the blend processing.Furthermore, this morphology of the blends has been proved to be stable after a reprocessing step in an internal mixer most likely due to either strong hydrogen bonds between the hydroxyl groups of starch and amide groups of polyamide 12 or to potentially cross reactions between macroradicals accounting for in situ formation of graft copolymers with the potential function of compatibilizers. Mechanical properties of the blends were found to be strongly dependent on the shear rate parameter of blend processing as the mechanical properties increase with shear rate. In agreement to the blend morphology, the elongation at break of the blends was greatly improved attesting of a good adhesion between both phases.