Effect of compatibilization on the properties of HIPS/PA1010 blends

Blends consisting of high‐impact polystyrene (HIPS) as the matrix and polyamide 1010 (PA1010) as the dispersed phase were prepared by mixing. The grafting copolymers of HIPS and maleic anhydride (MA), the compatibilizer precursors of the blends, were synthesized. The contents of the MA in the grafting copolymers are 4.7 wt % and 1.6 wt %, and were assigned as HAM and LMA, respectively. Different blend morphologies were observed by scanning electron microscopy (SEM); the domain size of the PA1010 dispersed phase in the HIPS matrix of compatibilized blends decreased comparing with that of uncompatibilized blends. For the blend with 25 wt % HIPS‐g‐MA component, the T_c of PA1010 shifts towards lower temperature, from 178 to 83°C. It is found that HIPS‐g‐MA used as the third component has profound effect on the mechanical properties of the resulting blends. This behavior has been attributed to the chemical reaction taking place in situ during the mixing between the two components of PA1010 and HIPS‐g‐MA. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 799–806, 2000     

Blends of polyamide1010 with unmodified and maleic‐anhydride‐grafted high‐impact polystyrene

The crystallization behaviors, dynamic mechanical properties, tensile, and morphology features of polyamide1010 (PA1010) blends with the high‐impact polystyrene (HIPS) were examined at a wide composition range. Both unmodified and maleic‐anhydride‐(MA)‐grafted HIPS (HIPS‐g‐MA) were used. It was found that the domain size of HIPS‐g‐MA was much smaller than that of HIPS at the same compositions in the blends. The mechanical performances of PA1010–HIPS‐g‐MA blends were enhanced much more than that of PA1010–HIPS blends. The crystallization temperature of PA1010 shifted towards higher temperature as HIPS‐g‐MA increased from 20 to 50% in the blends. For the blends with a dispersed PA phase (≤35 wt %), the T_c of PA1010 shifted towards lower temperature, from 178 to 83°C. An additional transition was detected at a temperature located between the T_g's of PA1010 and PS. It was associated with the interphase relaxation peak. Its intensity increased with increasing content of PA1010, and the maximum occurred at the composition of PA1010–HIPS‐g‐MA 80/20. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 857–865, 1999     

MORPHOLOGY,CRYSTALLIZATION BEHAVIORS,AND MECHANICAL PROPERTIES OF PA1010/HIPS AND PA1010/HIPS-g-MA BLENDS

The binary blends of polyamide 1010 (PA1010) with the high-impact polystyrene (HIPS)/maleic anhydride (MA) graft copolymer (HIPS-g-MA) and with HIPS were prepared using a wide composition range. Different blend morphologies were observed by scanning electron microscopy according to the nature and content of PA1010 used. Compared with the PA1010/HIPS binary blends, the domain sizes of dispersed-phase particles in PA1010/HIPS-g-MA blends were much smaller than that in PA1010/HIPS blends at the same compositions. It was found that the tensile properties of PA1010/HIPS-g-MA blends were obviously better than that of PA1010/HIPS blends. Wide-angle x-ray diffraction analyses were performed to confirm that the number of hydrogen bonds in the PA1010 phase decreased in the blends of PA1010/HIPS-g-MA. These behaviors could be attributed to the chemical interactions between the two components and good dispersion in PA1010/HIPS-g-MA blends.     

Effect of core‐shell morphology evolution on the rheology,crystallization, and mechanical properties of PA6/EPDM‐g‐MA/HDPE ternary blend

In this article, polyamide 6 (PA6), maleic anhydride grafted ethylene‐propylene‐diene monomer (EPDM‐g‐MA), high‐density polyethylene (HDPE) were simultaneously added into an internal mixer to melt‐mixing for different periods. The relationship between morphology and rheological behaviors, crystallization, mechanical properties of PA6/EPDM‐g‐MA/HDPE blends were studied. The phase morphology observation revealed that PA6/EPDM‐g‐MA/HDPE (70/15/15 wt %) blend is constituted from PA6 matrix in which is dispersed core‐shell droplets of HDPE core encapsulated by EPDM‐g‐MA phase and indicated that the mixing time played a crucial role on the evolution of the core‐shell morphology. Rheological measurement manifested that the complex viscosity and storage modulus of ternary blends were notable higher than the pure polymer blends and binary blends which ascribed different phase morphology. Moreover, the maximum notched impact strength of PA6/EPDM‐g‐MA/HDPE blend was 80.7 KJ/m² and this value was 10–11 times higher than that of pure PA6. Particularly, differential scanning calorimetry results indicated that the bulk crystallization temperature of HDPE (114.6°C) was partly weakened and a new crystallization peak appeared at a lower temperature of around 102.2°C as a result of co‐crystal of HDPE and EPDM‐g‐MA. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Rheological,thermal, and morphological properties of ABS–PA1010 blends

Noncompatibilized and compatibilized ABS–nylon1010 blends were prepared by melt mixing. Polystyrene and glycidyl methacrylate (SG) copolymer was used as a compatibilizer to enhance the interfacial adhesion and to control the morphology. This SG copolymer contains reactive glycidyl groups that are able to react with PA1010 end groups ( NH₂ or  COOH) under melt conditions to form SG‐g‐Nylon copolymer. Effects of the compatibilizer SG on the rheological, thermal, and morphological properties were investigated by capillary rheometer, DSC, and SEM techniques. The compatibilized ABS–PA1010 blend has higher viscosity, lower crystallinity, and smaller phase domain compared to the corresponding noncompatibilized blend. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 683–688, 1999     

Gasoline permeation behavior and mechanical properties of polyamide 6/nanoclay,polyamide 6/PE‐g‐maleic anhydride blend,and polyamide 6/PE‐g‐maleic anhydride/clay nanocomposite

In this article, polyamide 6 (PA6)/clay nanocomposites, PA6/polyethylene grafted maleic anhydride (PE‐g‐MA) blends, and PA6/PE‐g‐MA/clay nanocomposites were prepared and their gasoline permeation behavior and some mechanical properties were investigated. In PA6/clay nanocomposites, cloisite 30B was used as nanoparticles, with weight percentages of 1, 3, and 5. The blends of PA6/PE‐g‐MA were prepared with PE‐g‐MA weight percents of 10, 20, and 30. All samples were prepared via melt mixing technique using a twin screw extruder. The results showed that the lowest gasoline permeation occurred when using 3 wt % of nanoclay in PA6/clay nanocomposites, and 10 wt % of PE‐g‐MA in PA6/PE‐g‐MA blends. Therefore, a sample of PA6/PE‐g‐MA/clay nanocomposite containing 3 wt % of nanoclay and 10 wt % of PE‐g‐MA was prepared and its gasoline permeation behavior was investigated. The results showed that the permeation amount of PA6/PE‐g‐MA/nanoclay was 0.41 g m^?2 day^?1, while this value was 0.46 g m^?2 day^?1 for both of PA6/3wt % clay nanocomposite and PA6/10 wt % PE‐g‐MA blend. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40150.     

Experimental and computational investigation of EVOH/clay nanocomposites

Ethylene–vinyl alcohol copolymer (EVOH)/organoclay nanocomposites were prepared via a dynamic melt‐intercalation process. The effect of compatibilizers on the melt blending torque, intercalation level, and morphology of EVOH/organoclay systems was investigated. Maleic anhydride grafted ethylene vinyl acetate (EVA‐g‐ MA), or maleic anhydride grafted linear low‐density polyethylene (LLDPE‐g‐MA), were used to compatibilize EVOH with clay, at various concentrations (1, 5, and 10 wt %). Computer‐simulation techniques are used to predict structural properties and interactions of EVOH with compatibilizers in the presence and absence of clay. The simulation results strongly support the experimental findings and their interpretation. X‐ray diffraction shows enhanced intercalation within the galleries when the compatibilizers were added. Interestingly, results were obtained for the EVOH/clay/compatibilizer systems, owing to a high level of interaction developed in these systems. Thermal analysis shows that, upon increasing the compatibilizer content, lower crystallinity levels result, until at a certain compatibilizer content no crystallization is taking place. Significantly higher mixing viscosity levels were obtained for the EVOH/organoclay blends compared with the neat EVOH polymer. The storage modulus was higher compared with the uncompatibilized EVOH/organoclay blend in the presence of EVA‐g‐MA compatibilizer (at all concentrations), and only at low contents of LLDPE‐g‐MA. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2060–2066, 2005     

Toughening and compatibilization of polyphenylene sulfide/nylon 66 blends with SEBS and maleic anhydride grafted SEBS triblock copolymers

In this study, styrene‐b‐ethylene/butylene‐b‐styrene triblock copolymer (SEBS) and maleic anhydride grafted SEBS (SEBS‐g‐MA) were used as compatibilizers for the blends of polyphenylene sulfide/nylon 66 (PPS/PA66). The mechanical properties, including impact and tensile properties and morphology of the blends, were investigated by mechanical properties measurements and scanning electron microscopy. Impact measurements indicated that the impact strength of the blends increases slowly with elastomer (SEBS and SEBS‐g‐MA) content upto 20 wt %; thereafter, it increases sharply with increasing elastomer content. The impact energy of the elastomer‐compatibilized PPS/PA66 blends exceeded that of pure nylon 66, implying that the nylon 66 can be further toughened by the incorporation of brittle PPS minor phase in the presence of SEBS or SEBS‐g‐MA. The compatibilization efficiency of SEBS‐g‐MA for nylon‐rich PPS/PA66 was found to be higher than SEBS due to the in situ forming SEBS interphase between PPS and nylon 66. The correlation between the impact property and morphology of the SEBS‐g‐MA compatibilized PPS/PA66 blends is discussed. The excellent impact strength of the nylon‐rich blends resulted from shield yielding of the matrix. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Reactive Compatibilizer Precursors for LDPE/PA6 Blends, 4

Summary: The effectiveness of some thermoplastic elastomers grafted with maleic anhydride (MA) or with glycidyl methacrylate (GMA) as compatibilizer precursors (CPs) for blends of low density polyethylene (LDPE) with polyamide‐6 (PA) has been studied. The CPs were produced by grafting different amounts of MA or GMA onto a styrene‐block‐(ethylene‐co‐1‐butene)‐block‐styrene copolymer (SEBS) (KRATON G 1652), either in the melt or in solution. A commercially available SEBS‐g‐MA copolymer with 1.7 wt.‐% MA (KRATON FG 1901X) was also used. The effect of the MA concentration and of other characteristics of the SEBS‐g‐MA CPs was also studied. The specific interactions between the CPs and the blends components were investigated through characterizations of the binary LDPE/CP and PA/CP blends, in the whole composition range. It was demonstrated that the SEBS‐g‐GMA copolymers display poor compatibilizing effectiveness due to cross‐linking resulting from reactions of the epoxy rings of these CPs with both the amine and the carboxyl end groups of PA. On the contrary, the compatibilizing efficiency of the MA‐grafted elastomers, as revealed by the thermal properties and the morphology of the compatibilized blends, was shown to be excellent. The results of this study confirm that the anhydride functional groups possess considerably higher efficiency, for the reactive compatibilization of LDPE/PA blends, than those of the ethylene‐acrylic acid and ethylene‐glycidyl methacrylate copolymers investigated in previous works.

SEM micrograph of the 75/25 LD08/PA blend (with 2 phr SEBSMA1).     

Toughening PA1010 with a functionalized saturated polyolefin elastomer

Polyamide (PA)1010 is blended with a saturated polyolefin elastomer, ethylene‐α‐olefin copolymer (EOCP). To improve the compatibility of PA1010 with EOCP, different grafting rates of EOCP with maleic anhydride (MA) are used. The reaction between PA1010 and EOCP‐g‐MA during extrusion is verified through an extraction test. Mechanical properties, such as notched Izod impact strength, elongation at break, etc., are examined as a function of grafting rate and weight fraction of elastomer. It was found that in the scale of grafting rate (0.13–0.92 wt %), 0.51 wt % is an extreme point for several mechanical properties. Elastomer domains of PA1010/EOCP‐g‐MA blends show a finer and more uniform dispersion in the matrix than that of PA1010/EOCP blends. For the same grafting rate, the average sizes of elastomer particles are almost independent on the contents of elastomer, but for different grafting rates, the particle sizes are decreased with increasing grafting rate. The copolymer formed during extrusion strengthens the interfacial adhesion and acts as an emulsifier to prevent the aggregation of elastomer in the process of blending. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 928–933, 2000     

Influence of epoxy resin on the properties of maleic anhydride functionalized acrylonitrile–butadiene–styrene copolymer toughened polyamide 6 blends

Maleic anhydride functionalized acrylonitrile–butadiene–styrene copolymer (ABS‐g‐MA) was used as an impact modifier of polyamide 6 (PA6). Epoxy resin was introduced into PA6/ABS‐g‐MA blends to further improve their properties. Notched Izod impact tests showed that the impact strength of PA6/ABS‐g‐MA could be improved from 253 to 800 J/m with the addition of epoxy resin when the ABS‐g‐MA content was set at 25 wt %. Differential scanning calorimetry results showed that the addition of epoxy resin made the crystallization temperature and melting temperature shift to lower temperatures; this indicated the decrease in the PA6 crystallization ability. Dynamic mechanical analysis testing showed that the addition of epoxy resin induced the glass‐transition temperature of PA6 and the styrene‐co‐acrylonitrile copolymer phase to shift to higher temperatures due to the chemical reactions between PA6, ABS‐g‐MA, and epoxy resin. The scanning electron microscopy results indicated that the ABS‐g‐MA copolymer dispersed into the PA6 matrix uniformly and that the phase morphology of the PA6/ABS‐g‐MA blends did not change with the addition of the epoxy resin. Transmission electron microscopy showed that the epoxy resin did not change the deformation mechanisms of the PA6/ABS‐g‐MA blends. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Effects of addition of acrylic compatibilizer on the morphology and mechanical behavior of amorphous polyamide/SAN blends

Amorphous polyamide (aPA)/acrylonitrile‐styrene copolymer (SAN) blends were prepared using methyl methacrylate‐maleic anhydride copolymer MMA‐MA as compatibilizer. The aPA/SAN blends can be considered as a less complex version of the aPA/ABS (acrylonitrilebutadiene‐styrene) blends, due to the absence of the ABS rubber phase in the SAN material. It is known that acrylic copolymer might be miscible with SAN, whereas the maleic anhydride groups from MMA‐MA can react in situ with the amine end groups of aPA during melt blending. As a result, it is possible the in situ formation of aPA‐g‐MMA‐MA grafted copolymers at the aPA/SAN interface during the melt processing of the blends. In this study, the MA content in the MMA‐MA copolymer and its molecular weight was varied independently and their effects on the blend morphology and stress–strain behavior were evaluated. The morphology of the blends aPA/SAN showed a minimum in the SAN particle size at low amounts of MA in the compatibilizer, however, as the MA content in the MMA‐MA copolymer was increased larger SAN particle sizes were observed in the systems. In addition, higher MA content in the compatibilizer lead to less ductile aPA/SAN blends under tensile testing. The results shown the viscosity ratio also plays a very important role in the morphology formation and consequently on the properties of the aPA/SAN blends studied. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Effects of maleated syndiotactic polystyrene on the morphology,mechanical properties,and crystallization behavior of syndiotactic polystyrene/polyamide 6 blends

The compatibilization of syndiotactic polystyrene (sPS)/polyamide 6 (PA‐6) blends with maleic anhydride grafted syndiotactic polystyrene (sPS‐g‐MA) as a reactive compatibilizer was investigated. The sPS/PA‐6 blends were in situ compatibilized by a reaction between the maleic anhydride (MA) of sPS‐g‐MA and the amine end group of PA‐6. The occurrence of the chemical reaction was substantiated by the disappearance of a characteristic MA peak from the Fourier transform infrared spectrum. Morphology observations showed that the size of the dispersed PA‐6 domains was significantly reduced and that the interfacial adhesion was much improved by the addition of sPS‐g‐MA. As a result of reactive compatibilization, the impact strengths of the sPS/PA‐6 blends increased with an increase in the sPS‐g‐MA content. The crystallization behaviors of the blends were affected by the compatibilization effect of sPS‐g‐MA. A single melting peak of sPS in the noncompatibilized blend was gradually split into two peaks as the amount of the compatibilizer increased. A single crystallization peak of PA‐6 in the noncompatibilized blend became two peaks with the addition of 3 wt % sPS‐g‐MA. The new peak was a result of the fractionation crystallization. As the amount of sPS‐g‐MA increased, the intensity of the new peak increased, and the original peak nearly disappeared. Finally, the crystallization peak of PA‐6 disappeared with 20 wt % sPS‐g‐MA in the blend. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2502–2506, 2003     

Synthesis and properties of reactively compatibilized polyester and polyamide blends

The functionalization of poly(butylene terephthalate) (PBT) has been accomplished in a twin screw extruder by grafting maleic anhydride (MA) using a free radical polymerization technique. The resulting PBT‐g‐MA was successfully used as a compatibilizer for the binary blends of polyester (PBT) and polyamide (PA66). Enhanced mechanical properties were achieved for the blend containing a small amount (as low as 2.5 %) of PBT‐g‐MA compared to the binary blend of unmodified PBT with PA66. Loss and storage moduli for blends containing compatibilizer were higher than those of uncompatibilized blends or their respective polymers. The grafting and compatibilization reactions were confirmed using FTIR and ¹³C NMR spectroscopy. The properties of these blends were studied in detail by varying the amount of compatibilizer, and the improved mechanical behaviour was correlated with the morphology with the help of scanning electron microscopy. Morphology studies also revealed the interfacial interaction in the blend containing grafted PBT. The improvement in the properties of these blends can be attributed to the effective interaction of grafted maleic anhydride groups with the amino group in PA66. The results indicate that PBT‐g‐MA acts as an effective compatibilizer for the immiscible blends of PBT and PA66. © 2000 Society of Chemical Industry     

Compatibilizer in waste tire powder and low‐density polyethylene blends and the blends modified asphalt

With the increasing ratio of waste tire powder (WTP) to low‐density polyethylene (LDPE), the hardness and tensile strength of the WTP/LDPE blends decreased while the elongation at break increased. Five kinds of compatibilizers, such as maleic anhydride‐grafted polyethylene (PE‐g‐MA), maleic anhydride‐grafted ethylene‐octene copolymer (POE‐g‐MA), maleic anhydride‐grafted linear LDPE, maleic anhydride‐grafted ethylene vinyl‐acetate copolymer, and maleic anhydride‐grafted styrene‐ethylene‐butylene‐styrene, were incorporated to prepare WTP/LDPE blends, respectively. PE‐g‐MA and POE‐g‐MA reinforced the tensile stress and toughness of the blends. The toughness value of POE‐g‐MA incorporating blends was the highest, reached to 2032.3 MJ/m³, while that of the control was only 1402.9 MJ/m³. Therefore, POE‐g‐MA was selected as asphalt modifier. The toughness value reached to the highest level when the content of POE‐g‐MA was about 8%. Besides that the softening point of the modified asphalt would be higher than 60°C, whereas the content of WTP/LDPE blend was more than 5%, and the blends were mixed by stirring under the shearing speed of 3000 rpm for 20 min. Especially, when the blend content was 8.5%, the softening point arrived at 82°C, contributing to asphalt strength and elastic properties in a wide range of temperature. In addition, the swelling property of POE‐g‐MA/WTP/LDPE blend was better than that of the other compalibitizers, which indicated that POE‐g‐MA /WTP/LDPE blend was much compatible with asphalt. Also, the excellent compatibility would result in the good mechanical and processing properties of the modified asphalt. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Relationship between structure and properties in high‐performance PA6/SEBS‐g‐MA/(PPO/PS) blends: The role of PPO and PS

This work aimed at studying the role of poly(phenylene oxide) (PPO) and polystyrene (PS) in toughening polyamide‐6 (PA6)/styrene‐ethylene‐butadiene‐styrene block copolymer grafted with maleic anhydride (SEBS‐g‐MA) blends. The effects of weight ratio and content of PPO/PS on the morphology and mechanical behaviors of PA6/SEBS‐g‐MA/(PPO/PS) blends were studied by scanning electron microscope and mechanical tests. Driving by the interfacial tension and the spreading coefficient, the “core–shell” particles formed by PPO/PS (core) and SEBS‐g‐MA (shell) played the key role in toughening the PA6 blends. As PS improved the distribution of the “core–shell” particles due to its low viscosity, and PPO guaranteed the entanglement density of the PPO/PS phase, the 3/1 weight ratio of PPO/PS supplied the blends optimal mechanical properties. Within certain range, the increased content of PPO/PS could supply more efficient toughening particles and bring better mechanical properties. Thus, by adjusting the weight ratio and content of PPO and PS, the PA6/SEBS‐g‐MA/(PPO/PS) blends with excellent impact strength, high tensile strength, and good heat deflection temperature were obtained. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45281.     

Comparative study of different maleic anhydride grafted compatibilizer precursors towards LDPE/PA6 blends: Morphology and mechanical properties

The study deals with the effectiveness of maleic anhydride grafted styrene-b-ethylene-co-propylene copolymer (SEPMA) as compatibilizer precursor (CP) for blends of low density polyethylene (LDPE) with polyamide-6 (PA). The CP was produced by grafting MA onto SEP in the melt. The specific interactions between the CP and the blends components have been investigated through characterizations of the binary LDPE/CP and PA/CP blends. The compatibilizing efficiency of the MA-grafted SEP, as revealed by the thermal properties and the morphology of the compatibilized blends, has been shown to be excellent. The morphology, as well as the mechanical properties of the compatibilized with SEPMA 75/25 w/w and 25/75 w/w LDPE/PA6 blends have been compared with those of the blends compatibilized with maleic anhydride functionalized HDPE sample (1-HDPE-g-MA) and with a commercial maleic anhydride grafted styrene-b-(ethylene-co-1-butene)-b-styrene copolymer (SEBSMA1). The results show that the strong compatibilizing efficiency of SEPMA is comparable with that of SEBSMA1, while 1-HDPE-g-MA exhibits a slightly lower activity, particularly for the blends, in which PA is the matrix phase.     

Analysis of phase morphology and dynamics of immiscible PP/PA1010 blends and its partial-miscible blends during melt mixing from SEM patterns

The formation and evolution of the phase morphology of polypropylene (PP) with Nylon1010 (PA1010) blends before and after adding the compatibilizer, polypropylene grafted maleic anhydride (PP-g-MAH), during melt mixing are investigated by the pattern analysis of scanning electron microscope (SEM). The average particle diameter DP_AV, characteristic length Λ and the average characteristic length Λm are calculated to discuss the melt mixing process. It is proved, by the figure-estimation theory, that the distribution of Λ is log-normal distribution. Furthermore, the phase morphology during melt mixing is discussed in depth by the parameters of the log-normal distribution. The results demonstrate that the structure of the dispersed phase during melt mixing evolves with dynamical self-similarity through the competition of break-up and coalescence of dispersed phase. A fractal dimension, based on the probability density of the character length, is calculated in this study. The results show that the fractal dimension is an effective parameter to characterize the melt mixing process of polymer blends.     

Morphology and mechanical properties of polyamide 12 blends with styrene/ethylene–butylene/styrene rubbers with and without maleation

Blends of polyamide 12 (PA12) with styrene/ethylene–butylene/styrene (SEBS) and maleic anhydride grafted SEBS (SEBS‐g‐MA) were prepared by twin‐screw extrusion and injection molding. The morphology, mechanical properties, and dynamic mechanical properties of the blends were studied. The morphology of the blends was evaluated from the etched surfaces of cryogenically fractured specimens with scanning electron microscopy. The morphological parameters showed that the PA12/SEBS‐g‐MA blends (PM series) exhibited a finer and more uniform rubber dispersion than the PA12/SEBS blends (PS series) because of the interfacial chemical reactions. SEBS functionalization via maleic anhydride grafting strongly affected the morphological parameters, such as the domain size, interfacial area per unit of volume, and critical interparticle distance, but the distribution of the rubber domains in the blends was less affected. Tensile and impact studies showed that the PS blends had worse mechanical properties than the PM blends. The tensile strength and elongation at break of the PM blends were considerably greater than those of the PS blends. The fracture toughness and energy values determined for notched Charpy specimens in high‐speed impact tests were markedly higher for the PM blends than for the PS blends. A similar observation was obtained from instrumented falling weight impact studies. Dynamic mechanical analysis confirmed the incompatibility of the blend components because the glass‐transition temperatures of PA12 and the rubber phase (SEBS and SEBS‐g‐MA) were not affected. © 2005 Wiley Periodicals, Inc. J Appl polym Sci 95: 1376–1387, 2005     

Melt rheological properties of polypropylene–maleated polypropylene blends. I. Steady flow by capillary

Melt rheological properties of blends of polypropylene (PP) and PP grafted with maleic anhydride (PP‐g‐MA) are studied using a capillary rheometer. A pseudoplastic flow behavior is observed. The pseudoplasticity of the melt reduces with an increase of PP‐g‐MA content and/or temperature. The PP‐g‐MA component in the blend acts as decreasing melt viscosity, especially in the lower shear rate region, while the addition of PP‐g‐MA to PP does not cause obvious increase of die swell ratio. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1641–1648, 1999