Crystallization behavior of PP/PP‐g‐MAH/GFR PA66 blends: Establishment of their continuous‐cooling‐transformation of relative crystallinity diagrams

Polypropylene/polypropylene‐grafted‐maleic anhydride/glass fiber reinforced polyamide 66 (PP/PP‐g‐MAH/GFR PA 66) blends‐composites with and without the addition of polypropylene‐grafted‐maleic anhydride (PP‐g‐MAH) were prepared in a twin screw extruder. The effect of the compatibilizer on the thermal properties and crystallization behavior was determined using differential scanning calorimetry analysis. The hold time was set to be equal to 5 min at 290°C. These conditions are necessary to eliminate the thermomechanical history in the molten state. The crystallization under nonisothermal conditions and the plot of Continuous‐Cooling‐Transformation of relative crystallinity diagrams of both PP and PA 66 components proves that PP is significantly affected by the presence of PP‐g‐MAH. From the results it is found that an abrupt change is observed at 2.5 wt % of PP‐g‐MAH as a compatibilizer and then levels off. In these blends, concurrent crystallization behavior was not observed for GFR PA66. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1620–1626, 2007     

Mechanical properties of polypropylene/polyamide 6 blends: Effect of manufacturing processes and compatibilization

The properties of polypropylene (PP)/polyamide 6 (PA) blends, obtained by the following two different blending methods, were investigated. Blends of PP/PA and PP/PA/maleic anhydride have been prepared using a twin screw extruder and a fiber cutting, flying and mixing apparatus that directly commingles PP fiber and PA fiber. The properties measured include rheological properties by means of a capillary rheometer, morphologies by scanning electron microscopy, and mechanical properties by a universal testing machine and a high rate impact tester. In the presence of compatibilizer, a marked dispersibility of the polymer blends of PP and PA was observed, and mechanical properties were found to increase as a result of improvement of the interfacial adhesion and the dispersibility. The properties of PP/PA blends manufactured by two different pieces of equipment were shown to be similar in the case of melting both resins. But in particular, superior impact properties were obtained in blends not melting PA fibers as a dispersed phase rather than blends using maleic anhydride grafted polypropylene (PP-g-MA) as a compatibilizer.     

Co-continuous and encapsulated three phase morphologies in uncompatibilized and reactively compatibilized polyamide 6/polypropylene/polystyrene ternary blends using two reactive precursors

Phase morphology development in ternary uncompatibilized and reactively compatibilized blends based on polyamide 6 (PA6), polypropylene (PP) and polystyrene (PS) has been investigated. Reactive compatibilization of the blends has been performed using two reactive precursors; maleic anhydride grafted polypropylene (PP-g-MA) and styrene maleic anhydride copolymer (SMA) for PA6/PP and PA6/PS pairs, respectively. For comparison purposes, uncompatibilized and reactively compatibilized PA6/PP and PA6/PS binary blends, were first investigated. All the blends were melt-blended using a co-rotating twin-screw extruder. The phase morphology investigated using scanning electron microscope (SEM) and selective solvent extraction tests revealed that PA6/PP/PS blends having a weight percent composition of 70/15/15 is constituted from polyamide 6 matrix in which are dispersed composite droplets of PP core encapsulated by PS phase. Whereas, a co-continuous three-phase morphology was formed in the blends having a composition of 40/30/30. This morphology has been significantly affected by the reactive compatibilization. In the compatibilized PA6/(PP/PP–MA)/(PS/SMA) blends, PA6 phase was no more continuous but gets finely dispersed in the PS continuous phase. The DSC measurements confirmed the dispersed character of the PA6 phase. Indeed, in the compatibilized PA6/(PP/PP–MA)/(PS/SMA) blends where the PA6 particle size was smaller than 1 μm, the bulk crystallization temperature of PA6 (188 °C) was completely suppressed and a new crystallization peak emerges at a lower temperature of 93 °C as a result of homogeneous nucleation of PA6.     

Morphological properties,rheological behaviors,and phase interaction of nylon 11/polypropylene blends by in situ reactive compatibilization and dispersion through polyhydroxybutyrate

The current research discusses the reactive compatibilization of nylon 11 (PA11) and polypropylene (PP) using maleic anhydride grafted PP (PP-g-MA) through an extruder. PP phase is dispersed in PA11 by coalescence and droplet break-up mechanism by using polyhydroxybutyrate (PHB) as a dispersion agent that induces uniform interaction between the blend components. The reactive compatibilization ensures the mixing of polymers, and the consistent interaction of phases is controlled by dispersion. All of the blends were processed through melt processing at different compositions using a twin-screw extruder. Scanning electron microscopy was used to determine the morphologies of the binary and ternary blends. Surface tension and interfacial tension of the homopolymer characterizes the interaction of the polymers at interphase. The interaction of PHB/PA11 appeared preferable than that of PHB/PP, elaborating on the efficient dispersion and droplet formation of the PP phase. The compatibilizer maleic anhydride grafted PP (PP-g-MA) imparts a drastic effect on the compatibility of PA11-PP and PA11-PHB-PP blends and reduces PP phase particle size, which indicates the affinity of PHB and PP. The encapsulation of PP by PHB was seen in the expectation of minimum free energy models. The rheological measurements were used to understand the phase separation within blends. These measurements were also applied to understand the interaction between PA11-PP-PHB phases. The modulus values and viscosity ratio of the blends were measured to follow the chain relaxation in the melt. In the Cole–Cole plot, it was found that the reduction in PP phase size influences the relaxation of chains of blends.     

Melt rheological properties of polypropylene–polyamide6 blends compatibilized with maleic anhydride‐grafted polypropylene

The melt rheological properties of binary uncompatibilized polypropylene–polyamide6 (PP–PA6) blends and ternary blends compatibilized with maleic anhydride‐grafted PP (PP–PP‐g‐MAH–PA6) were studied using a capillary rheometer. The experimental shear viscosities of blends were compared with those calculated from Utracki's relation. The deviation value δ between these two series of data was obtained. In binary PP–PA6 blends, when the compatibility between PP and PA6 was poor, the deformation recovery of dispersed PA6 particles played the dominant role during the capillary flow, the experimental values were smaller than those calculated, and δ was negative. The higher the dispersed phase content, the more deformed the droplets were and the lower the apparent shear viscosity. Also, the absolute value of δ increased with the dispersed phase composition. In ternary PP–PP‐g‐MAH–PA6 systems, when the compatibility between PP and PA6 was enhanced by PP‐g‐MAH, the elongation and break‐up of the dispersed particles played the dominant role, and the experimental values were higher than calculated. It was observed that the higher the dispersion of the PA6 phase, the higher the δ values of the ternary blends and the larger the positive deviation. Unlike uncompatibilized blends, under high shear stress with higher dispersed phase content, the PP‐g‐PA6 copolymer in compatibilized blends was pulled out from the interface and formed independent micelles in the matrix, which resulted in reduced total apparent shear viscosity. The δ value decreased with increasing shear stress. Copyright © 2006 Society of Chemical Industry     

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     

Study on the microstructure and properties of bromobutyl rubber (BIIR)/polyamide‐12 (PA12) thermoplastic vulcanizates (TPVs)

In this study, polyamide‐12 (PA12)/brominated isobutylene‐isoprene (BIIR) TPVs with good mechanical properties and low gas permeability were prepared by dynamic vulcanization in a twin‐screw extruder. The effects of three kinds of compatibilizers on the microstructure and properties of BIIR/PA12 TPV were studied. The compatibility between BIIR and PA12 was improved when maleated hydrocarbon polymeric compatibilizer is added. The reaction between maleic anhydride and amine in polyamide leads to the in situ formation of hydrocarbon polymer grafted polyamide which subsequently can be used to lower the interfacial tension between BIIR and polyamide. The compatibilizing effect of maleic anhydride modified polypropylene (PP‐g‐MAH) on BIIR/PA12 blends is the best among these compatibilizers because the surface energy of PP‐g‐MAH is very close to that of BIIR. The dispersed rubber phase of the blend compatibilized by PP‐g‐MAH shows the smallest size and more uniform size distribution, and the resulting TPVs show the best mechanical properties. The effects of fillers on the properties of BIIR/PA12 TPV were also investigated. The size of the BIIR phase increases with the increase in the content of CaCO₃. The modulus and tensile strength of TPVs increased with the increase in the content of CaCO₃ because of the reinforcing effect of CaCO₃ on TPVs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43043.     

The morphology of hyperbranched polymer compatibilized polypropylene/polyamide 6 blends

The influence of hyperbranched polymer grafted polypropylene (PP‐HBP) on the morphology of polypropylene (PP)/polyamide 6 (PA6) blends has been investigated. The final morphology was strongly influenced by the PP‐HBP compatibilizer concentration. At low concentrations, PP‐HBP acts as an emulsifying agent, reducing the size of the dispersed phase and preventing coalescence. This is due to the high reactivity and diffusitivity of PP‐HBP rapidly forming a high density of copolymers at the interface. Compared to the use of maleic anhydride grafted PP (PP‐MAH) at identical concentrations, PP‐HBP yielded a smaller dispersed phase particle size. Therefore, PP‐HBP allows the use of less compatibilizer to obtain identical morphologies. At higher compatibilizer concentrations, it has been shown that the PP‐HBP efficiently stabilizes the interface and inhibits both coalescence and breakup of the PA6 droplets. The high concentration of reactive sites and the ability of PP‐HBP to react with both chain‐ends of PA6 suggest that interfacial stabilization occurs because of the formation of a partly crosslinked interface. The interfacial stabilization effects generated by PP‐HBP should allow one to control the morphology of polymer blends in order to create specific functional morphologies.     

多单体接枝聚丙烯对PP/PA6共混物形态及力学性能的影响

用同向双螺杆挤出机制备了马来酸酐(MAH)、苯乙烯(St)多单体熔融接枝聚丙烯[PP-g-(St-MAH)],将其作为增容剂在Haake转矩流变仪上与PP/PA6共混得到PP/PA6/PP-g-(St-MAH)共混物,并对共混物的性能及结构进行了表征。结果表明,该增容剂明显改善了共混物的力学性能,当增容剂含量为15~20份时,共混物的冲击强度和拉伸屈服强度达最大值。采用扫描电子显微镜观察共混物试样断面的形态,发现分散相的粒径明显减小,且分散均匀。     

Real time assessment of the compatibilization of polypropylene/polyamide 6 blends during extrusion

The reactivity of maleic anhydride and acrylic acid polypropylene graft copolymers with amine groups and their effect in the compatibilization of polymer blends was analyzed in real time during the reactive processing of compatilized polypropylene/polyamide 6 (PP/PA6) blends. The presence of compatibilizers in the blend produces a block copolymer PP‐PA6, which stays in the blends interface, lowering the interfacial tension and reducing the PA6 particle size, affecting the light extinction phenomena. The in‐line optical detector is able to indirectly quantify the conversion of the compatibilization reaction of the blends. The signal intensity of the detector increases with the increase of the PA6 content due to the increase in the number of particles. Quantitative off‐line FTIR analyses of the compatibilized blends have shown that the amount of block copolymer formed when polypropylene grafted with acrylic acid (PP‐g‐AA) is used as compatibilizer increases with its content in the blend. There is a good correlation between the in‐line optical measurement and the off‐line amidic bond content formed. Non‐reacted compatibilizers are always present in the reactive blends whose content is proportional to its initial concentration. The PA6 particle size data obtained from scanning electron microscopy analysis showed good correlation with the in‐line measurements. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers     

PP/PA11合金的结晶性能研究

用马来酸酐接枝聚丙烯(PP-g-MA)和苯乙烯-马来酸酐无规共聚物(RSMA)作增容剂,制备了PP/PA11合金,并对合金的结晶性能进行了研究。傅立叶转换红外光谱(FTIR)表明,RSMA的增容机理与PP-g-MA不同。比较了2种增容体系的差示扫描量热(DSC)曲线,发现PP-g-MA增容体系中PP的熔融温度向更高温度移动,同时PP-g-MA的加入更能影响PP和PA11两相的结晶,使体系的结晶度增大,从而使合金的缺口冲击性能表现出更强的脆性。     

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     

Reactive melt blending of modified polyamide and polypropylene: Assessment of compatibilization by fractionated crystallization and blend morphology

The melting and crystallization behavior of nonreactive and reactive melt‐mixed blends of polypropylene and carboxylic‐modified polyamide (mPA) as the dispersed phase was investigated. It was found that the size of the mPA particles decreases and the crystallization behavior of the mPA particles changes in dependence on the mixing time of the blends with oxazoline‐modified PP (mPP). This indicates that an in situ reaction occurs between the oxazoline groups of mPP and the carboxylic acid groups of mPA, resulting in a compatibilizing effect. In blends with mPP, the crystallization of the dispersed mPA phase splits into two steps. Below a critical particle size, the mPA does not crystallize at temperatures typical for bulk crystallization. These finely dispersed mPA particles crystallize coincidently with the PP phase, and this part increases with increasing mixing time. Analysis of the crystallization heat of both steps in connection with the particle volume distribution permits the estimation of the critical particle size to be ≤4 μm. These investigations showed that the effect of fractionated crystallization can be used to follow the morphology development and to evaluate the efficiency of compatibilizing interfacial reactions during processing. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3445–3453, 2002     

Investigation of crystallization behavior in dynamically vulcanized EPDM–nylon copolymer blends

A thermoplastic vulcanizate (TPV) of a ethylene–propylene–diene terpolymer (EPDM) and nylon copolymer (PA) was prepared by dynamic vulcanization. Maleic anhydride (MAH)–grafted EPDM (EPDM–g–MAH), MAH‐grafted EPR (EPR–g–MAH), and chlorinated polyethylene (CPE) were used as compatibilizers. The effect of dynamic vulcanization and compatibilizer on the crystallization behavior of PA was investigated. Differential scanning calorimeter measurement results showed no pronounced shift in the crystallization temperature for PA in EPDM–PA TPV compared to that for PA in the neat state, whereas the crystallization temperature increased after adding compatibilizer. The decrease in the crystallinity of TPVs was a result of the crystallization occurring in confined spaces between rubber particles. The equilibrium melting temperature (Tm⁰) of the PA copolymer was measured and was determined to be 157°C. The isothermal crystallization kinetics of PA in the neat and TPV states also was investigated. The crystallization rate was highest in the compatibilized TPV and lowest in the neat PA, whereas it was intermediate in the uncompatibilized TPV unvulcanized blends. Compared with unvulcanized EPDM–PA blends, the dynamic vulcanization process seemed to cause an obvious increase in the crystallization rate of the PA copolymer, especially when a suitable compatibilizer was used. This occurred because the dynamic vulcanization introduced fine crosslinked rubber particles that could act as heterogeneous nucleating centers. In addition, the use of a suitable compatibilizer permitted the formation of finely dispersed vulcanized rubber particles and therefore increased the density of the nucleating centers. The complex morphology of the blends was investigated by atomic force microscopy to evaluate the effect of compatibilizer on the size of the dispersed rubber particles. Compared with the morphology of TPVs with the same dosage of EPDM–g–MAH compatibilizer, the morphology of TPVs using EPR–g–MAH as compatibilizer showed much smaller dispersed rubber particles, which may have contributed to the higher crystallization rate. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 824–829, 2003     

Crystallization behavior of polypropylene/polyamide 6/montmorillonite nanocomposites

Polymer blended materials such as polyamide 6 (PA6)/polypropylene (PP) blends have received considerable attention in recent years. To improve the compatibility of PA6 and PP, compatibilizers like maleic anhydride‐g‐polypropylene (MPP) are often added. In addition, organically modified montmorillonite (MMT) is also used to improve the properties of various materials. In this work, the crystallization behavior of PP/PA6/MMT nanocomposites with MPP compatibilizer was investigated systematically. The annealing process effectively improved the crystallization of α‐PP. The crystallization temperature (T_c) of PA6 was increased by ca 2–3 °C on introducing MPP or MMT alone to the PP/PA6 system, whereas T_c of PP underwent no obvious change. However, when MPP and MMT were added simultaneously, T_c of PP and PA6 increased by 6.6 and 4.2 °C, respectively, and a new crystallization peak corresponding to PP‐g‐PA6 copolymer phase was observed at 162.5 °C. The combined effect of MPP and MMT led to better compatibility of PP with PA6. Moreover, the results of a non‐isothermal crystallization kinetics experiment revealed that the simultaneous introduction of MPP and MMT markedly shortened the crystallization time. Copyright © 2010 Society of Chemical Industry     

Blend compatibilizers based on silane‐ and maleic anhydride–modified polyolefins

Polypropylene (PP)/polyamide blends were compatibilized with PP modified with vinylsilane or maleic anhydride and ethylene–propylene random (EPR) copolymer modified with maleic anhydride. The thermal behavior, mechanical properties, and morphology of the blends were investigated. Thermal analysis showed that the polyamide crystallization temperatures shifted downward with all compatibilizers, whereas its melting behavior did not change. On the other hand, polypropylene crystallization temperatures shifted upward in all cases, except for blends containing EPR modified with maleic anhydride. Tensile strength and elongation at break increased for blends compatibilized with modified PP. Blends containing up to 7% of EPR modified with maleic anhydride did not show good yield stresses. The morphology of the blends showed a finer dispersion of the polyamide minor phase in the PP matrix. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2492–2498, 2003     

Relationship between interfacial tension and dispersed‐phase particle size in polymer blends. II. PP/PA6

Simple blends with different viscosity ratios of the components as well as compatibilized blends varying both in type and content of the compatibilizers were used to study the relation between the interfacial tension and the dispersed‐phase particle size for PP/PA6 (80/20 wt %) blends in this work. Four compatibilizing systems including poly(ethylene‐co‐methacrylic acid) ionomers, a maleic anhydride‐grafted propylene copolymer, maleic anhydride‐grafted polypropylene, and a maleic anhydride‐grafted styrene ethylene butylene copolymer were used. For blends prepared in an internal mixer, a power‐law relation was found between the capillary number and the torque ratio of the blends' components. This relation was used to estimate the interfacial tension for the compatibilized blends. The relation between the steady‐state torque of the blends as a measure of viscosity and the estimated values of interfacial tension were also investigated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 54–63, 2003     

Compatibilization and morphology development of immiscible ternary polymer blends

We report a novel and effective strategy that compatibilizes three immiscible polymers, polyolefins, styrene polymers, and engineering plastics, achieved by using a polyolefin-based multi-phase compatibilizer. Compatibilizing effect and morphology development are investigated in a model ternary immiscible polymer blends consisting of polypropylene (PP)/polystyrene(PS)/polyamide(PA6) and a multi-phase compatibilizer (PP-g-(MAH-co-St) as prepared by maleic anhydride (MAH) and styrene (St) dual monomers melt grafting PP. Scanning electron microscopy (SEM) results indicate that, as a multi-phase compatibilizer, PP-g-(MAH-co-St) shows effective compatibilization in the PP/PS/PA6 blends. The particle size of both PS and PA6 is greatly decreased due to the addition of multi-phase compatibilizer, while the interfacial adhesion in immiscible pairs is increased. This good compatibilizing effect is promising for developing a new, technologically attractive method for achieving compatibilization of immiscible multi-component polymer blends as well as for recycling and reusing of such blends. For phase morphology development, the morphology of PP/PS/PA6 (70/15/15) uncompatibilized blend reveals that the blend is constituted from PP matrix in which are dispersed composite droplets of PA6 core encapsulated by PS phase. Whereas, the compatibilized blend shows the three components strongly interact with each other, i.e. multi-phase compatibilizer has good compatibilization between the various immiscible pairs. For the 40/30/30 blend, the morphology changed from a three-phase co-continuous morphology (uncompatibilized) to the dispersed droplets of PA6 and PS in the PP matrix (compatibilized).     

Interfacial effects produced by crystallization of polypropylene with polypropylene-g-maleic anhydride compatibilitzers

Two anydride-grafted isotactic polypropylene (PP) compatibilizers, HAC or high-anydride compatibilizer (2.7 wt % grafted maleic anhydride) and LAC or low-anydride compatibilizer (0.2 wt % anydride), were compared in PP-rich blends with polyamide-66 (25 wt %). A previous article demonstrated that LAC imparted a much higher fracture strain than did HAC at similar anydride concentrations. The present study shows that LAC is capable of cocrystallization with PP. HAC does not cocrystallize, but crystallizes as a second phase in binary PP/HAC blends studied by DSC and hot-stage microscopy. A cocrystallization model is proposed to explain the higher fracture strain of PP/LAC/PA blends. A. separate phase crystallization model is proposed for PP/HAC/PA blends. The models are supported by peel tests, which demonstrate greater adhesion of PP with LAC than with HAC. © 1994 John Wiley & Sons, Inc.     

Non-isothermal crystallization kinetic and compatibility of PTT/PP blends by using maleic anhydride grafted polypropylene as compatibilizer

The crystallization behaviors, non-isothermal crystallization kinetics, and the morphology of poly(trimethylene terephthalate)/Polypropylene (PTT/PP) blends using a maleic anhydride grafted polypropylene (PP-g-MAH) as a compatibilizer were investigated by differential scanning calorimeter (DSC) and scanning electron microscope (SEM), respectively. The results suggested that the blends exhibited different crystallization and melting behaviors due to different content of PP-g-MAH. All of the DSC curves of the blends exhibited two exothermic peaks and endothermic peaks. The commonly used Avrami equation modified by Jeziorny, Ozawa theory and the method developed by Mo were used, respectively, to fit the primary stage of non-isothermal crystallization process. The results suggested that the crystallization rate of PTT component was increased, whereas, that of PP component was retarded with the introduction of PP-g-MAH. The effective activation energy was calculated by differential iso-conversional method developed by Vyazovkin. The SEM result suggested that the introduction of PP-g-MAH greatly improved the compatibility between PTT and PP, and decreased the size of dispersed particles.