Effect of the compatibilizer on the morphology and properties of dynamically cured PP/POE/epoxy blends

Dynamic vulcanization was successfully applied to epoxy resin reinforced polypropylene (PP)/ethylene‐octene copolymer (POE) blends, and the effects of different compatibilizers on the morphology and properties of dynamically cured PP/POE/epoxy blends were studied. The results show that dynamically cured PP/POE/epoxy blends compatibilized with maleic anhydride‐grafted polypropylene (MAH‐g‐PP) have a three‐phase structure consisting of POE and epoxy particles dispersed in the PP continuous phase, and these blends had improved tensile strength and flexural modulus. While using maleic anhydride‐grafted POE (MAH‐g‐POE) as a compatibilizer, the structure of the core‐shell complex phase and the PP continuous phase showed that epoxy particles could be embedded in MAH‐g‐POE in the blends, and gave rise to an increase in impact strength, while retaining a certain strength and modulus. DSC analysis showed that the epoxy particles in the blends compatibilized with MAH‐g‐PP were more efficient nucleating agents for PP than they were in the blends compatibilized with MAH‐g‐POE. WAXD analysis shows that compatibilization do not disturb the crystalline structure of PP in the blends. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Toughening of recycled poly(ethylene terephthalate)/glass fiber blends with ethylene–butyl acrylate–glycidyl methacrylate copolymer and maleic anhydride grafted polyethylene–octene rubber

The aim of this study was to improve the toughness of recycled poly(ethylene terephthalate) (PET)/glass fiber (GF) blends through the addition of ethylene–butyl acrylate–glycidyl methacrylate copolymer (EBAGMA) and maleic anhydride grafted polyethylene–octene (POE‐g‐MAH) individually. The morphology and mechanical properties of the ternary blend were also examined in this study. EBAGMA was more effective in toughening recycled PET/GF blends than POE‐g‐MAH; this resulted from its better compatibility with PET and stronger fiber/matrix bonding, as indicated by scanning electron microscopy images. The PET/GF/EBAGMA ternary blend had improved impact strength and well‐balanced mechanical properties at a loading of 8 wt % EBAGMA. The addition of POE‐g‐MAH weakened the fiber/matrix bonding due to more POE‐g‐MAH coated on the GF, which led to weakened impact strength, tensile strength, and flexural modulus. According to dynamic rheometer testing, the use of both EBAGMA and POE‐g‐MAH remarkably increased the melt storage modulus and dynamic viscosity. Differential scanning calorimetry analysis showed that the addition of EBAGMA lowered the crystallization rate of the PET/GF blend, whereas POE‐g‐MAH increased it. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Influence of a compatibilizer on the properties of polyethylene–octene elastomer/starch blends

The effect of a compatibilizer on the properties of corn starch‐reinforced metallocene polyethylene–octene elastomer (POE) blends was studied. The compatibility between POE and starch was improved markedly with an acrylic acid‐grafted POE (POE‐g‐AA) copolymer as a compatibilizer. Fourier transform infrared spectroscopy, X‐ray diffraction spectroscopy, differential scanning calorimetry, and scanning electron microscopy were used to examine the blends produced. The size of the starch phase increased with an increasing content of starch for noncompatibilized and compatibilized blends. The POE/starch blends compatibilized with the POE‐g‐AA copolymer lowered the size of the starch phase and had a fine dispersion and homogeneity of starch in the POE matrix. This better dispersion was due to the formation of branched and crosslinked macromolecules because the POE‐g‐AA copolymer had anhydride groups to react with the hydroxyls. This was reflected in the mechanical properties of the blends, especially the tensile strength at break. In a comparison with pure POE, the decrease in the tensile strength was slight for compatibilized blends containing up to 40 wt % starch. The POE‐g‐AA copolymer was an effective compatibilizer because only a small amount was required to improve the mechanical properties of POE/starch blends. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1792–1798, 2002     

Dynamic rheological and morphological study of the compatibility of thermoplastic polyurethane/ethylene–octene copolymer blends

Two grafted ethylene–octene copolymers [POEs; i.e., POE‐g‐maleic anhydried (MAH) and aminated POE (denoted by POE‐g‐NH₂) were used as compatibilizers in immiscible blends of thermoplastic polyurethane (TPU) and POE. The effects of the compatibilizers on the dynamic rheological properties and morphologies of the TPU/POE blends were investigated. The characteristic rheological behaviors of the blends indicated that the strong interactions between the two phases were due to the compatibilization. Microstructural observation confirmed that the compatibilizers were located at the interface in the blends and formed a stable interfacial layer and smaller dispersed phase particle size. Compared with POE‐g‐MAH, POE‐g‐NH₂ exhibited a better compatibilization effect in the TPU/POE blends. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Study on toughening effect of maleic anhydride‐grafted‐poly(ethylene‐octene) to EVOH and their compatibility

Blends of poly(ethylene‐co‐vinyl alcohol) (EVOH) with maleic anhydride‐grafted‐poly(ethylene‐octene) (POE‐g‐MAH) were prepared by blending extrusion in order to improve the toughness and flexibility of EVOH. The compatibility behavior of these blends with POE‐g‐MAH content range from 0 to 25 wt% was studied using mechanical, thermal, infrared, and morphology characterization techniques. The mechanical test results showed that POE‐g‐MAH can significantly improve the impact toughness of EVOH with a brittle‐tough transition appeared at the POE‐g‐MAH content of 20 wt%. A huge increase of toughness of the blend was also observed when the POE‐g‐MAH content was increased to 15 wt%. The thermal analysis of the blends demonstrated that the thermal stability of EVOH is improved with the addition of POE‐g‐MAH, adding 20 wt% or more POE‐g‐MAH can effectively decrease the crystallinity of EVOH and greatly improve compatibility between the two components. The existence of esterification between anhydride groups in POE‐g‐MAH and hydroxyl groups in EVOH in melt processing was confirmed using Fourier transform infrared technique. Morphology analysis of the Izod impact fractures has clearly shown the mechanisms for these blends to change from brittle to tough with increasing the POE‐g‐MAH content. POLYM. ENG. SCI., 53:2093–2101, 2013. © 2013 Society of Plastics Engineers     

Influence of high density polyethylene‐g‐maleic anhydride on compatibility and properties of poly(butylene terephthalate)/high density polyethylene blends

Poly(butylene terephthalate)/high density polyethylene (PBT/HDPE) blends and PBT/HDPE‐grafted maleic anhydride (PBT/HDPE‐g‐MAH) blends were prepared by the reactive extrusion approach, and the effect of blend compositions on the morphologies and properties of PBT/HDPE blends and PBT/HDPE‐g‐MAH blends was studied in detail. The results showed that flexural strength, tensile strength, and notched impact strength of PBT/HDPE blends decreased with the addition of HDPE, and flexural strength and tensile strength of PBT/HDPE‐g‐MAH blends decreased, while the notched impact strength of PBT/HDPE‐g‐MAH increased with the addition of HDPE‐g‐MAH. Compared with PBT/HDPE blends, the dimension of the dispersed phase particles in PBT/HDPE‐g‐MAH blends was decreased and the interfacial adhesion was increased. On the other hand, the effects of HDPE and HDPE‐g‐MAH contents on the crystalline and the rheological properties of the blends were also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 6081–6087, 2006     

Waste ground rubber tire powder/thermoplastic vulcanizate blends: Preparation,characterization, and compatibility

In this article, waste ground rubber tire (WGRT) powder was introduced into thermoplastic vulcanizate (TPV) to prepare the blends of WGRT powder/TPV. The mechanical, rheological, thermal aging, and dynamic properties of the blends were investigated with respect to the particle size and dosage of WGRT powder. The results showed that tensile strength, tear strength, elongation at break, and tensile permanent deformation of the blends increased with the decrease in WGRT particle size and decreased with the dosage of WGRT. The effects of different types and dosages of compatibilizers on mechanical and rheological properties of the blends were studied. The results showed that the compatibilizer PP‐g‐MAH could effectively improve the interfacial compatibility between WGRT and the TPV matrix to enhance the comprehensive properties of blends. The TPV/WGRT/PP‐g‐MAH blends obtained the best overall properties when prepared at the weight ratio 100/30/5. Rheological studies demonstrated that the WGRT/TPV blends represented lower apparent viscosity after PP‐g‐MAH were added, which means that processing performance of the blends was improved by PP‐g‐MAH. Scanning electron microscopy was used to study the morphologies of the blends. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39868.     

Morphology and mechanical properties of polyamide‐6/K resin blends

Mechanical properties and morphological studies of compatibilized blends of polyamide‐6 (PA‐6)/K resin grafted with maleic anhydride (K‐g‐MAH) and PA‐6/K resin/K‐g‐MAH were investigated as functions of K resin/K‐g‐MAH and dispersed phase K resin concentrations, and all the blends were prepared using twin screw extruder followed by injection molding. Scanning electron microscopy (SEM) were used to assess the fracture surface morphology and the dispersion of the K resin in PA‐6 continuous phase, the results showing extensive deformation in presence of K‐g‐MAH, whereas, uncompatibilized PA‐6/K resin blends show dislodging of K resin domains from the PA‐6 matrix. Dynamic mechanical thermal analysis (DMTA) test reveals the partially miscibility of PA‐6 with K‐g‐MAH, and differential scanning calorimetry (DSC) results further identified that the introduction of K‐g‐MAH greatly improved the miscibility between PA‐6 and K resin. The mechanical properties of PA‐6/K resin blends and K‐g‐MAH were studied through bending, tensile, and impact properties. The Izod notch impact strength of PA‐6/K‐g‐MAH blends increase with the addition of K‐g‐MAH, when the K‐g‐MAH content adds up to 20 wt %, the impact strength is as more than 6.2 times as pure PA‐6, and accompanied with small decrease in the tensile and bending strength less than 12.9% and 17.5%, respectively. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Toughening effects of ethylene–vinyl acetate copolymers with different vinyl acetate content and viscosity on nylon 1010 blends

Nylon 1010 blends with ethylene–vinyl acetate copolymer (EVA) and maleated ethylene–vinyl acetate (EVA‐g‐MAH) were prepared through melt blending. The vinyl acetate (VA) content and viscosity of EVA significantly affected the notched impact strength of nylon/EVA/EVA‐g‐MAH (80/15/5) blends. The nylon/EVA/EVA‐g‐MAH blends with high notched impact strength (over 60 kJ/m²) were obtained when the VA content in EVA ranged from 28 to 60 wt%. The effect of VA content on the notched impact strength of blends was related to the glass transition temperature for EVA with high VA content and crystallinity for EVA with low VA content. For nylon blends with EVA with the same VA content, low viscosity of EVA led to high notched impact strength. Fracture morphology of nylon/EVA/EVA‐g‐MAH (80/15/5) blends showed that blends with ductile fracture behavior usually had large matrix plastic deformation, which was the main energy dissipation mechanism. A relationship between the notched impact strength and the morphology of nylon/EVA/EVA‐g‐MAH (80/15/5) blends was well correlated by the interparticle distance model. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

Study on thermal stability and flame retardancy of polymer/layered silicate nanocomposites based on POE and POE‐g‐MAH

Ethylene‐octene elastomer (POE)/organo‐montmorillonite (OMT) and maleic anhydride‐grafted POE (POE‐g‐MAH)/OMT composites were prepared through melt mixing and influence of clay dispersion on thermal, dynamic mechanical, and flammability properties were investigated. The results showed that OMT forms intercalated/exfoliated structures in POE‐g‐MAH/OMT and agglomerated structure in POE/OMT microcomposites, resulting in more significant improvements of storage modulus and glass transition temperature in the POE‐g‐MAH/OMT rather than the POE/OMT composites. The POE‐g‐MAH/OMT nanocomposites have better thermal stability and significantly reduced flammability than the POE/OMT microcomposites, which was discussed on the basis of cone colorimeter test of the composites and energy dispersive X‐ray spectrum analysis of the combustion chars. POLYM. ENG. SCI., 54:2911–2917, 2014. © 2014 Society of Plastics Engineers     

Preparation and properties of dynamically cured PP/MAH‐g‐EVA/epoxy blends

A method concerning with the simultaneous reinforcing and toughening of polypropylene (PP) was reported. Dynamical cure of the epoxy resin with 2‐ethylene‐4‐methane‐imidazole (EMI‐2,4) was successfully applied in the PP/maleic anhydride‐grafted ethylene‐vinyl acetate copolymer (MAH‐g‐EVA), and the obtained blends named as dynamically cured PP/MAH‐g‐EVA/epoxy blends. The stiffness and toughness of the blends are in a good balance, and the smaller size of epoxy particle in the PP/MAH‐g‐EVA/epoxy blends shows that MAH‐g‐EVA was also used as a compatibilizer. The structure of the dynamically cured PP/MAH‐g‐EVA/epoxy blends is the embedding of the epoxy particles by the MAH‐g‐EVA. The cured epoxy particles as organic filler increases the stiffness of the PP/MAH‐g‐EVA blends, and the improvement in the toughness is attributed to the embedded structure. The tensile strength and flexural modulus of the blends increase with increasing the epoxy resin content, and the impact strength reaches a maximum of 258 J/m at the epoxy resin content of 10 wt %. DSC analysis shows that the epoxy particles in the dynamically cured PP/MAH‐g‐EVA/epoxy blends could have contained embedded MAH‐g‐EVA, decreasing the nucleating effect of the epoxy resin. Thermogravimetric results show the addition of epoxy resin could improve the thermal stability of PP, the dynamically cured PP/MAH‐g‐EVA/epoxy stability compared with the pure PP. Wide‐angle x‐ray diffraction analysis shows that the dynamical cure and compatibilization do not disturb the crystalline structure of PP in the blends. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Modification of polyethylene–octene elastomer by silica through a sol–gel process

In this study, tetraethoxysilane (TEOS) and a metallocene polyethylene–octene elastomer (POE) were chosen as the ceramic precursor and the continuous phase, respectively, for the preparation of new hybrids by an in situ sol–gel process. To obtain a better hybrid, a maleic anhydride‐grafted polyethylene–octene elastomer (POE‐g‐MAH), used as the continuous phase, was also investigated. Characterizations of POE‐g‐MAH/SiO₂ and POE/SiO₂ hybrids were performed by Fourier transform infrared (FTIR) and ²⁹Si solid‐state nuclear magnetic resonance (NMR) spectrometers, a differential scanning calorimeter (DSC), a thermogravimetry analyzer, and an Instron mechanical tester. The results showed that the POE‐g‐MAH/SiO₂ hybrid could improve the properties of the POE/SiO₂ hybrid because the interfacial force between the polymer matrix and the silica network was changed from hydrogen bonds into covalent Si? O? C bonds through dehydration of hydroxy groups in POE‐g‐MAH with residual silanol groups in the silica network. The existence of covalent Si? O? C bonds was proved by FTIR spectra. For the POE/SiO₂ and POE‐g‐MAH/SiO₂ hybrids, maximum values of the tensile strength and the glass transition temperature were found at 9 wt % SiO₂ since a limited content of silica might be linked with the polymer chains through the covalent bond. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 966–972, 2003     

Study on the microstructures and mechanical behaviour of compatibilized polypropylene/polyamide‐6 blends

A series of blends of polypropylene (PP)–polyamide‐6 (PA6) with either reactive polyethylene–octene elastomer (POE) grafted with maleic anhydride (POE‐g‐MA) or with maleated PP (PP‐g‐MA) as compatibilizers were prepared. The microstructures and mechanical properties of the blends were investigated by means of tensile and impact testing and by scanning electron microscopy and transmission electron microscopy. The results indicated that the miscibility of PP–PA6 blends was improved with the addition of POE‐g‐MA and PP‐g‐MA. For the PP/PA6/POE‐g‐MA system, an elastic interfacial POE layer was formed around PA6 particles and the dispersed POE phases were also observed in the PP matrix. Its Izod impact strength was four times that of pure PP matrix, whilst the tensile strength and Young's modulus were almost unchanged. The greatest tensile strength was obtained for PP/PA6/PP‐g‐MA blend, but its Izod impact strength was reduced in comparison with the pure PP matrix. © 2002 Society of Chemical Industry     

Dynamically cured polypropylene/Novolac blends compatibilized with maleic anhydride‐g‐polypropylene

In this article, the dynamic vulcanization process was applied to polypropylene (PP)/Novolac blends compatibilized with maleic anhydride‐grafted PP (MAH‐g‐PP). The influences of dynamic cure, content of MAH‐g‐PP, Novolac, and curing agent on mechanical properties of the PP/Novolac blends were investigated. The results showed that the dynamically cured PP/MAH‐g‐PP/Novolac blend had the best mechanical properties among all PP/Novolac blends. The dynamic cure of Novolac improved the modulus and stiffness of the PP/Novolac blends. The addition of MAH‐g‐PP into dynamically cured PP/Novolac blend further enhanced the mechanical properties. With increasing Novolac content, tensile strength, flexural modulus, and flexural strength increased significantly, while the elongation at break dramatically deceased. Those blends with hexamethylenetetramine (HMTA) as a curing agent had good mechanical properties at HMTA content of 10 wt %. Scanning electron microscopy (SEM) analysis showed that dynamically cured PP/MAH‐g‐PP/Novolac blends had finer domains than the PP/MAH‐g‐PP/Novolac blends. Thermogravimetric analysis (TGA) results indicated that the incorporation of Novolac into PP could improve the thermal stability of PP. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Dynamically cured polypropylene/epoxy blends

The dynamic vulcanization process, usually used for the preparation of thermoplastic elastomers, was used to prepare polypropylene (PP)/epoxy blends. The blends had crosslinked epoxy resin particles finely dispersed in the PP matrix, and they were called dynamically cured PP/epoxy blends. Maleic anhydride grafted polypropylene (MAH‐g‐PP) was used as a compatibilizer. The effects of the reactive compatibilization and dynamic cure were studied with rheometry, capillary rheometry, and scanning electron microscopy (SEM). The crystallization behavior and mechanical properties of PP/epoxy, PP/MAH‐g‐PP/epoxy, and dynamically cured PP/epoxy blends were also investigated. The increase in the torque at equilibrium for the PP/MAH‐g‐PP/epoxy blends indicated the reaction between maleic anhydride groups of MAH‐g‐PP and the epoxy resin. The torque at equilibrium of the dynamically cured PP/epoxy blends increased with increasing epoxy resin content. Capillary rheological measurements also showed that the addition of MAH‐g‐PP or an increasing epoxy resin content increased the viscosity of PP/epoxy blends. SEM micrographs indicated that the PP/epoxy blends compatibilized with PP/MAH‐g‐PP had finer domains and more obscure boundaries than the PP/epoxy blends. A shift of the crystallization peak to a higher temperature for all the PP/epoxy blends indicated that uncured and cured epoxy resin particles in the blends could act as effective nucleating agents. The spherulites of pure PP were larger than those of PP in the PP/epoxy, PP/MAH‐g‐PP/epoxy, and dynamically cured PP/epoxy blends, as measured by polarized optical microscopy. The dynamically cured PP/epoxy blends had better mechanical properties than the PP/epoxy and PP/MAH‐g‐PP/epoxy blends. With increasing epoxy resin content, the flexural modulus of all the blends increased significantly, and the impact strength and tensile strength increased slightly, whereas the elongation at break decreased dramatically. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1437–1448, 2004     

Effects of clay contents on the dynamic mechanical and rheological properties of polypropylene/MAH‐g‐POE/clay composites

A series of polypropylene/maleic anhydride grafted polypropylene octane elastomer (MAH‐g‐POE)/clay (PPMC) nanocomposites were prepared with a novel compatilizer MAH‐g‐POE and different contents of octadecyl amine modified montmorillonite, and the effects of clay contents on the dynamic mechanical and rheological properties of these PPMC composites were investigated. With clay content increasing, the characteristic X‐ray diffraction peak changed from one to two with intensity decreasing, indicating the decreasing concentration of the intercalated clay layers. The gradual decrease of crystallization temperature of PPMC composites with the increase of clay loading should be attributed to the preferred intercalation of MAH‐g‐POE molecules into clay interlayer during blending, which is also reflected by scanning electron microscopy observations. By evaluating the activation energy for the glass transition process of MAH‐g‐POE and polypropylene (PP) in the PPMC composites, it is found that clay intercalation could cause the restriction effect on the glass transition of both MAH‐g‐POE and PP, and this restriction effect appears stronger for PP and attained the highest degree at 5 wt % clay loading. The melt elasticity of PP could be improved apparently by the addition of MAH‐g‐POE, and 5 wt % clay loading is enough for further enhancing the elastic proportion of PP. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synergetic toughness and morphology of poly(propylene)/nylon 11/maleated ethylene‐propylene diene copolymer blends

Polypropylene (PP)/nylon 11/maleated ethylene‐propylene‐diene rubber (EPDM‐g‐MAH) ternary polymer blends were prepared via melt blending in a corotating twin‐screw extruder. The effect of nylon 11 and EPDM‐g‐MAH on the phase morphology and mechanical properties was investigated. Scanning electron microscopy observation revealed that there was apparent phase separation for PP/EPDM‐g‐MAH binary blends at the level of 10 wt % maleated elastomer. For the PP/nylon 11/EPDM‐g‐MAH ternary blends, the dispersed phase morphology of the maleated elastomer was hardly affected by the addition of nylon 11, whereas the reduced dispersed phase domains of nylon 11 were observed with the increasing maleated elastomer loading. Furthermore, a core‐shell structure, in which nylon 11 as a rigid core was surrounded by a soft EPDM‐g‐MAH shell, was formed in the case of 10 wt % nylon 11 and higher EPDM‐g‐MAH concentration. In general, the results of mechanical property measurement showed that the ternary blends exhibited inferior tensile strength in comparison with the PP matrix, but superior toughness. Especially low‐temperature impact strength was obtained. The toughening mechanism was discussed with reference to the phase morphology. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Properties and morphologies of PVC/nylon terpolymer blends

A new kind of blends of polyvinyl chloride (PVC)/nylon terpolymer was reported in this article. Two compatibilizers were used in this study: one is a terpolymer of ethylene–n‐butyl acrylate–monoxide (EnBACO); the other is terpolymer of EnBACO grafted with maleic anhydride (EnBACO‐g‐MAH). The observation of scanning electron microscope (SEM) reveals that the PVC/nylon terpolymer blends have a two‐phase structure; and the nylon terpolymer phase is the continuous phase, and PVC domains in the PVC/nylon terpolymer/EnBACO‐g‐MAH blends have fine dispersion over a broad range of the PVC/nylon terpolymer ratio. EnBACO‐g‐MAH is more compatible with the nylon terpolymer than EnBACO. EnBACO and EnBACO‐g‐MAH have different effects on the glass transition temperatures of the PVC phase and nylon terpolymer phase in the blends. The notched Izod impact strength, tensile strength, elongation at break, Vicat softening temperature (VST), and melt flow index (MFI) critically depend on PVC/nylon terpolymer ratio, the kinds and concentration of the compatibilizers. The PVC/nylon terpolymer/EnBACO‐g‐MAH blends display a good combination of high toughness, high flowability, and high VST under low load. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2823–2832, 2001     

Effect of starch ratio and compatibilization on the viscoelastic behavior of POE/starch blends

In this research, polyolefin elastomers (POE)/starch blends were prepared using an internal mixer with 0 to 55 wt% starch content, and MAH was added into POE/starch blend to prepare a composite that improves its biodegradation, while tuning the viscoelastic behavior and morphology. The effect of the composition and the compatibilizer addition on properties, such as morphology, rheology, and the creep behavior, was investigated. The observations of microstructures through thescanning electron microscope (SEM) showed that in the incompatibilized blends, the interfacial adhesion of the phases was very weak. In contrast, in compatibilized samples, the broken surface of starch was observed confirming the enhanced interfacial tension. Additionally, the increase in the starch content led to the rise in the relaxation times. The creep test results revealed that with the increment of starch content, the creep of the blends increased. The compatibilizer improved the creep recovery of the blends. Moreover, by addition of the compatibilizer, the values of the creep parameters including η, E₁, E_2, and τ_R obtained from the standard linear solid model (SLS), was higher than those for the incompatibilized blends. The addition of POE-MA compatibilizer can improve the properties of POE/starch blends, while keeping their biocompatibility. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48877.     

Compatibilization of polypropylene/Poly(acrylonitrile‐butadiene‐styrene) blends by polypropylene‐graft‐cardanol

The polypropylene‐graft‐cardanol (PP‐g‐cardanol) was prepared by reactive extrusion with polypropylene (PP) and natural renewable cardanol which could increase the interfacial energy of PP and inhibit the degradation of PP during the process of reactive extrusion and usage. In this article, PP‐g‐cardanol and polypropylene‐graft‐maleic anhydride (PP‐g‐MAH) were used as compatibilizers of the polypropylene (PP)/poly(acrylonitrile‐butadiene‐styrene) (ABS) blends. PP/ABS (70/30, wt %) blends with PP‐g‐cardanol and PP‐g‐MAH were prepared by a corotating twin‐screw extruder. From the results of morphological studies, the droplet size of ABS was minimized to 1.93 and 2.01 μm when the content of PP‐g‐cardanol and PP‐g‐MAH up to 5 and 7 phr, respectively. The results of mechanical testing showed that the tensile strength, impact strength and flexural strength of PP/ABS (70/30) blends increase with the increasing of PP‐g‐cardanol content up to 5 phr. The complex viscosity of PP/ABS (70/30) blends with 5 phr PP‐g‐cardanol showed the highest value. Moreover, the change of impact strength and tensile strength of PP/ABS (70/30) blends were investigated by accelerated degradation testing. After 4 accelerated degradation cycles, the impact strength of the PP/ABS (70/30) blends with 5 phr PP‐g‐cardanol decrease less than 6%, but PP/ABS (70/30) blends with 5 phr PP‐g‐MAH and without compatibilizer decrease as much as 12% and 32%, respectively. The tensile strength of PP/ABS (70/30) blends has a similar tendency to that of impact strength. The above results indicated that PP‐g‐cardanol could be used as an impact modifier and a good compatibilizer, which also exhibited better stability performance during accelerated degradation testing. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41315.