Morphological and mechanical properties of PP/ABS blends compatibilized with PP‐g‐acrylic acid

Polypropylene (PP) and acrylonitrile–butadiene–styrene (ABS) blends were prepared by a melt extrusion process. PP‐g‐acrylic acid was used as a compatibilizer. Blends with various compositions of PP, compatibilizer, and ABS were prepared and studied for morphological and mechanical properties. PP‐rich ternary blends showed good morphological and mechanical properties. The use of 5 wt % PP‐g‐acrylic acid as a compatibilizer resulted in a fine and homogeneous dispersion of the ABS phase in the PP phase. The experimental data of the tensile modulus showed good agreement in PP‐rich compositions with that generated from Kerner's model with perfect adhesion. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1731–1741, 2001     

Melt rheological properties of PBT/SEBS and reactively compatibilized PBT/SEBS/SEBS‐g‐MA polymer blends

Melt rheological properties of PBT/SEBS and PBT/SEBS/SEBS‐g‐MA blends at SEBS volume fraction (Φ_d) = 0.00–0.38 were studied at 240°C, 250°C and 260°C using a capillary rheometer. The compatibilizer SEBS‐g‐MA addition resulted in significant reduction in the dynamic interfacial tension which in turn led to increased phase adhesion. The power law exponent n decreased with increasing Φ_d and increasing temperature for both the compatiblized and uncompatiblized blends. The consistency index of PBT/SEBS increased with increasing Φ_d but were smaller than those of PBT/SEBS/SEBS‐g‐MA blends. Melt elasticity such as die swell and first normal stress difference increased with Φ_d. Variations of first normal stress coefficient function (ψ₁), recoverable shear strain (γ_R), relaxation time (λ), and shear compliance (J_c) values versus shear rate were analyzed. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41402.     

An investigation on recycled PET/PP and recycled PET/PP‐EP compatibilized blends: Rheological,morphological, and mechanical properties

The effectiveness of P(E‐co‐MA‐co‐GMA) as a compatibilizer for recycled PET/PP and recycled PET/PP‐EP (polypropylene (ethylene‐propylene) heterophase copolymer) blends was investigated by means of morphological (scanning electron microscopy), rheological (small amplitude oscillatory shear), mechanical (tensile, flexural and impact tests), and thermal (differential scanning calorimetry) properties. Compatibilizer concentration ranged from 1 to 5 wt % with respect to the whole blend. All blends were obtained in a 90/10 composition using a twin screw extruder. Compatibilization effects for PETr/PP‐EP were more pronounced due to ethylene segments present in both PP‐EP and P(E‐co‐EA‐co‐GMA). PETr/PP‐EP has shown greater dispersed phase size reduction, a more solid‐like complex viscosity behavior and larger storage modulus at low frequencies in relation to PETr/PP blend. For both investigated blends, mechanical properties indicated an improvement in both elongation at break and impact strength with increasing compatibilizer content. PETr/PP‐EP blends showed improved performance for the same level of compatibilizer content. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41892.     

Melt rheological properties of reactive compatibilized HDPE/PET blends

Melt rheological properties of high density polyethylene and poly(ethylene terephthalate) (HDPE/PET) blends compatibilized by an ethylene–butyl acrylate–glycidyl methacrylate terpolymer (EBAGMA) were studied by means of a HAAKE torque rheometer and a capillary rheometer. The phase morphology of the blends was evaluated by a scanning electron microscope (SEM). The results showed that the melts of blends behave pseudoplasticity. The addition of EBAGMA strengthens the interfacial adhesion between HDPE and PET and improves the phase dispersion due to reactive compatibilization. It was observed that the balance torque, melt viscosity, and sensitivity of melt viscosity to shear rate of the melts increase with increasing content of EBAGMA, but the melt flow index and activation energy decrease. At the same time, the plasticizing time is shortened indicating that the processability of the compatibilized blends has been improved. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

PP/PET共混熔体的流变性能研究

以PP-g-AA作增容剂,研究了PP/PET共混熔体的流变行为。讨论了温度、剪切速率以及PET和增容剂含量对熔体表观粘度、非牛顿指数等方面的影响。结果表明,PP/PET共混物熔体表观粘度随剪切速率的增大而降低,随PET及增容剂含量的增加而下降,随温度的升高而下降。PET和增容剂的加入,在共混熔体中起到了增塑剂的作用。     

Linear viscoelastic behavior of compatibilized PMMA/PP blends

In this work, the morphology and linear viscoelastic behavior of PMMA/PP blends to which a graft copolymer PP‐g‐PMMA has been added was studied. The copolymer concentration varied from 1 to 10 wt % relative to the dispersed phase concentration. The rheological data were used to infer the interfacial tension between the blended components. It was observed that PP‐g‐PMMA was effective as a compatibilizer for PMMA/PP blends. For PP‐g‐PMMA concentration added below the critical concentration of interface saturation, two rheological behaviors were observed depending on the blend concentration: for 70/30 blend, the storage modulus, at low frequencies, increased as compared to the one of the unmodified blend; for 90/10 blend, it decreased. For 90/10 blend, the relaxation spectrum presented an interfacial relaxation time related to the presence of the compatibilizer (τ_β). For PP‐g‐PMMA concentrations added above the critical concentration of interface saturation, the storage modulus of all blends increased as compared with the one of the unmodified blend. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Mechanical properties and morphology of PP/ABS blends compatibilized with PP‐g‐2‐HEMA

Polypropylene (PP) and acrylonitrile–butadiene–styrene blends of different composition were prepared using a single‐screw extruder. The binary blend of PP/ABS was observed to be incompatible and shows poor mechanical properties. PP‐g‐2‐hydroxyethyl methacrylate (2‐HEMA) was used as a compatibilizer for the PP/ABS blends. The ternary compatibilized blends of PP/ABS/PP‐g‐2‐HEMA showed improvement in the mechanical properties. Electron micrographs of these blends showed a homogeneous and finer distribution of the dispersed phase. The mechanical performance increased particularly in the PP‐rich blend. The 2.5‐phr (part per hundred of resin) compatibilizer was observed to bring improvement to the properties. The suitability of various existing theoretical models for the predication of the tensile moduli of these blends was examined. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 72–78, 2003     

Polypropylene/polyethylene blends as models for high‐impact propylene–ethylene copolymers,part 1: Interaction between rheology and morphology

In this work, composition effects on interfacial tension and morphology of binary polyolefin blends were studied using rheology and electron microscopy. The amount of dispersed phase (5–30 wt %) and its type [ethylene–octene copolymer, linear low‐density polyethylene (LLDPE), and high‐density polyethylene] was varied, and the influence of different matrix materials was also studied by using a polypropylene homopolymer and a ethylene–propylene (EP) random copolymer. The particle size distribution of the blends was determined using micrographs from transmission electron microscopy (TEM). A clear matrix effect on the flow behavior could be found from the viscosity curves of the blends. Analyzing the viscosity of the blends applying the logarithmic mixing rule indicated a partial miscibility of the EP random copolymer with low amounts of the LLDPE in the melt. Micrographs from TEM also showed a clear difference in morphology if the base polymer is changed, with PE lamellae growing out of the inclusions or being present directly embedded in the matrix. To verify these findings, the interfacial tension was determined. The applicability of Palierne's emulsion model was found to be limited for such complex systems, whereas Gramespacher–Meissner analysis led to interfacial tensions comparable with those already reported in the literature. The improved compatibility when changing the matrix polymer from the homopolymer to the random copolymer allows the development of multiphase materials with finer phase structure, which will also result in improved mechanical and optical performance. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Mechanical and thermal properties of SEBS‐g‐MA compatibilized halloysite nanotubes reinforced polyethylene terephthalate/polycarbonate/nanocomposites

In this study, the effect of maleic anhydride grafted styrene‐ethylene‐butylene‐styrene (SEBS‐g‐MA) content on mechanical, thermal, and morphological properties of polyethylene terephthalate/polycarbonate/halloysite nanotubes (PET/PC/HNTs) nanocomposites has been investigated. Nanocomposites of PET/PC (70 : 30) with 2 phr of HNTs were compounded using the counter rotating twin screw extruder. A series of formulations were prepared by adding 5–20 phr SEBS‐g‐MA to the composites. Incorporation of 5 phr SEBS‐g‐MA into the nanocomposites resulted in the highest tensile and flexural strength. Maximum improvement in the impact strength which is 245% was achieved at 10 phr SEBS‐g‐MA content. The elongation at break increased proportionately with the SEBS‐g‐MA content. However, the tensile and flexural moduli decreased with increasing SEBS‐g‐MA content. Scanning electron microscopy revealed a transition from a brittle fracture to ductile fracture morphology with increasing amount of SEBS‐g‐MA. Transmission electron microscopy showed that the addition of SEBS‐g‐MA into the nanocomposites promoted a better dispersion of HNTs in the matrix. A single glass transition temperature was observed from the differential scanning calorimetry test for compatibilized nanocomposites. Thermogravimetric analysis of PET/PC/HNTs nanocomposites showed high thermal stability at 15 phr SEBS‐g‐MA content. However, on further addition of SEBS‐g‐MA up to 20 phr, thermal stability of the nanocomposites decreased due to the excess amount of SEBS‐g‐MA. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42608.     

Phase behavior of binary blends of PP/PP‐g‐AA: limitations of the conventional characterization techniques

In this study, miscibility/immiscibility issues of a binary blend consisting of polypropylene (PP) and acrylic acid grafted polypropylene (PP‐g‐AA) were investigated using rheometry, DSC, dynamic mechanical and thermal analysis (DMTA), AFM and time‐of‐flight secondary‐ion mass spectrometry (ToF‐SIMS). Phase separation analysis of such blend systems is a challenge and complex due to chemically similar components as well as the low value of acrylic acid groups in the graft copolymer. Thus, it is crucial to determine if the present blend shows some degree of miscibility or develops co‐continuous morphology between the components. The analysis of rheometrical, DSC and DMTA results indicated no sensitivity of these classical techniques for detecting the miscibility or immiscibility of such a system. However, AFM data effectively detected dispersed‐phase domains corresponding to the PP‐g‐AA rich phase. The results, for the first time, indicated that the start of phase separation occurs at a critical copolymer concentration between 2 and 5 wt%. Furthermore it was observed that, as the PP‐g‐AA content increases, the size and continuity of the dispersed phase increase and reach a highly continuous morphology. Additionally, ToF‐SIMS chemical imaging was carried out to aid in the interpretation of the AFM data. © 2016 Society of Chemical Industry     

Polypropylene–clay blends compatibilized with MAH‐g‐POE

A series of new Polypropylene (PP)–clay blends, containing 5 wt % clay, were prepared by melt compounding with maleic anhydride grafted poly(ethylene‐co‐octene) (MAH‐g‐POE) as the compatibilizer by varying its content from 0 to 20 wt %. The effect of MAH‐g‐POE on the PP–clay miscibility was examined by X‐ray diffraction (XRD), scanning electronic microscope (SEM) observation, differential scanning calorimeter (DSC) analysis, dynamic mechanical thermal analysis (DMTA), and rheological testing in sequence. The results showed that the addition of MAH‐g‐POE could improve the dispersion of clay layers in PP matrix and promoted the interaction between PP molecules and clay layers. At 10 wt % MAH‐g‐POE, the PP–clay blend exhibited a highest value of Tc,onset and Tg as well as a biggest melt storage modulus (G′), indicating the greatest PP–clay interaction. On the other hand, improved toughness and stiffness coexisted in blends with 5–10 wt % loading of MAH‐g‐POE. In view of SEM and DMTA observations, MAH‐g‐POE was well miscible with the PP matrix, even with the concentration up to 20 wt %. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 2558–2564, 2006     

Morphology,crystallization, and thermal behavior of isotactic polypropylene/propylene‐g‐styrene blends

Optical microscopy, differential scanning calorimetry, and small angle X‐ray scattering techniques were used to study the influence of the crystallization conditions on morphology and thermal behavior of samples of binary blends constituted of isotactic polypropylene (iPP) and a novel graft copolymer of unsaturated propylene with styrene (uPP‐g‐PS) isothermally crystallized from melt, at relatively low undercooling, in a range of crystallization temperatures of the iPP phase. It was shown that, irrespective of composition, no fall in the crystallinity index of the iPP phase was observed. Notwithstanding, spherulitic texture and thermal behavior of the iPP phase in the iPP/uPP‐g‐PS materials were strongly modified by the presence of copolymer. Surprisingly, iPP spherulites crystallized from the blends showed size and regularity higher than that exhibited by plain iPP spherulites. Moreover, the amount of amorphous material located in the interspherulitic amorphous regions decreased with increasing crystallization temperature, and for a given crystallization temperature, with increasing uPP‐g‐PS content. Also, relevant thermodynamic parameters, related to the crystallization process of the iPP phase from iPP/uPP‐g‐PS melts, were found, composition dependent. The equilibrium melting temperature and the surface free energy of folding of the iPP lamellar crystals grown in the presence of uPP‐g‐PS content up to 5% (wt/wt) were, in fact, respectively slightly lower and higher than that found for the lamellar crystals of plain iPP. By further increase of the copolymer content, both the equilibrium melting temperature and surface free energy of folding values were, on the contrary, depressed dramatically. The obtained results were accounted for by assuming that the iPP crystallization process from iPP/uPP‐g‐PS melts could occur through molecular fractionation inducing a combination of morphological and thermodynamic effects. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 2286–2298, 2001     

PTT/PP-g-MAH/PP共混材料形态和流变性能研究

以毛细管流变仪和扫描电子显微镜研究了聚对苯二甲酸丙二醇酯(PTT)/聚丙烯接枝马来酸酐(PP-g-MAH)/聚丙烯(PP)共混体系的形态和流变行为。讨论了共混物的组成、增容剂含量对共混物的形态、熔体流变行为的影响。结果表明:PP-g-MAH改善了PP与PTT的相容性,PP在PTT连续相中分散均匀,分散相尺寸随着增容剂含量的增加而减小。共混物熔体为假塑性流体,其非牛顿指数n、熔体黏度、黏流活化能随增容剂含量的增加而降低。     

PP／PET／EPDM-g-GMA共混物结构与性能研究

通过反应共混制备了PP／PET／EPDM—g-GMA共混物。用扫描电镜和图像处理软件对共混物形貌进行定性和定量分析，用偏光显微镜观察共混物等温结晶形态，最后测量共混物的力学性能。结果表明：在PP／PET共混物中加入EPDM-g—GMA后，两相相容性改善，进一步加入成核剂后分散相尺寸更小、粒径分布更均匀；PP球晶随PET的混入而减小；在PP／PET体系中加入EPDM-g—GMA起到反应增容和橡胶增韧的协同效应，使缺口冲击强度由未加增容剂时的2．0kJ／m^2提高至6．6k．1／m^2，弹性模量较PP提高了38％；PP／PET共混物的拉伸强度随PET含量的增加下降，在相同PET含量的情况下，加入EPDM—g-GMA后，共混物的拉伸强度与未增容体系基本一致。     

Thermostimulative shape memory effect of linear low‐density polyethylene/polypropylene (LLDPE/PP) blends compatibilized by crosslinked LLDPE/PP blend (LLDPE–PP)

A novel linear low‐density polyethylene (LLDPE)/polypropylene (PP) thermostimulative shape memory blends were prepared by melt blending with moderate crosslinked LLDPE/PP blend (LLDPE–PP) as compatibilizer. In this shape memory polymer (SMP) blends, dispersed PP acted as fixed phase whereas continuous LLDPE phase acted as reversible or switch phase. LLDPE–PP improved the compatibility of LLDPE/PP blends as shown in scanning electron microscopic photos. Dynamic mechanical analysis test showed that the melt strengths of the blends were enhanced with increasing LLDPE–PP content. A shape memory mechanism for this type of SMP system was then concluded. It was found that when the blend ratio of LLDPE/PP/LLDPE–PP was 87/13/6, the blend exhibited the best shape memory effect at stretch ratio of 80%, stretch rate of 25 mm/min, and recovery temperature of 135°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.     

PP/PE blends. IV. Characterization and compatibilization of blends of postconsumer resin with virgin PP and HDPE

The mechanical properties of blends of isotactic polypropylene and high-density polyethylene with a postconsumer resin (recycled dairy containers) were investigated over the entire composition range. Modification of these blends with an ethylene/propylene/diene copolymer or an ethylene/vinyl acetate copolymer was also investigated. Isotactic polypropylene/postconsumer resin blends have satisfactory impact and tensile properties at postconsumer resin contents of less than 50% for certain applications. At higher postconsumer resin contents, the tensile properties were adversely affected. The impact properties remained satisfactory. Addition of an ethylene/propylene/diene copolymer improved the mechanical properties of these blends to levels equal to or greater than those for neat isotactic polypropylene. Ethylene/vinyl acetate copolymers were also able to improve the mechanical properties, but not as efficiently as did the ethylene/propylene/diene copolymer. Blends of high-density polyethylene and a postconsumer resin had poor impact and tensile properties. Although the ethylene/propylene/diene copolymer and ethylene/vinyl acetate copolymers were able to improve these properties, the improvement was insufficient for general recycling, except at lower (≤25%) postconsumer resin contents. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 2081–2095, 1998     

表面处理纳米铜粉/PET共混物的流变性能

采用硅烷偶联剂KH-550对纳米铜粉进行表面处理,通过熔融共混制备纳米铜粉/PET共混物,用毛细管流变仪研究了共混物的流变性能。结果表明:纳米铜粉/PET共混体系为非牛顿性假塑性流体,其表观黏度随着剪切速率的增大而减小;随着纳米铜粉含量增加,非牛顿指数增大;共混物的黏流活化能随剪切速率的增加而减小。     

Rheological and thermal properties of single‐site polyethylene blends

Branched polyethylenes, low‐density polyethylenes (LDPE1 and LDPE2) or long‐chain‐branched very low density polyethylenes (VLDPE2), were blended with very low density polyethylenes containing short branches (VLDPE1 and VLDPE3). The rheological and thermal measurements of the pure copolymers and their blends (VLDPE1–LDPE1, VLDPE1–LDPE2, VLDPE1–VLDPE2, and VLDPE2–VLDPE3) were taken by controlled stress rheometry and differential scanning calorimetry, respectively. The shear‐thinning effect became stronger with increasing long‐chain‐branched polymer compositions when it was correlated with the flow behavior index, and the extent of shear thinning was different for each blend set. Stronger shear thinning and a linear composition dependence of the zero‐shear viscosity were observed for the VLDPE1–LDPE1 and VLDPE1–LDPE2 blends. These blends followed the log additivity rule, and this indicated that they were miscible in the melt at all compositions. In contrast, a deviation from the log additivity rule was observed for the VLDPE1–VLDPE2 blend compositions with 50% or less VLDPE2 and for the VLDPE3–VLDPE2 blends with 50% or more VLDPE2. The thermal properties of the blends were consistent with the rheological properties. VLDPE1–LDPE1 and VLDPE1–LDPE2 showed that these blends were characteristic of a single‐component system at all compositions, whereas the phase separation (immiscibility) was detected only for VLDPE1–VLDPE2 blends with 50% or less VLDPE2 and for VLDPE3–VLDPE2 blends with 50% or more VLDPE2. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1549–1557, 2005     

增容聚丙烯/聚苯乙烯共混物的相形态

综述了作为增容剂的接枝共聚物与嵌段共聚物,反应增容,其他技术增容以及共混条件对聚丙烯／聚苯乙烯(PP,PS)共混物的相形态研究进展。PP／PS共混物通过增容可以改善共混物相形态和提高界面粘结,这为提高PP／PS共混物的物理与力学性能提供了依据。     

The mechanical and rheological behavior of the PA/TPU blend with POE‐g‐MA modifier

In this research, we attempt to improve the impact strength and the viscosity of PA (polyamide) by blending two elastomers, TPU (thermoplastic polyurethane) and POE‐g‐MA (maleic anhydride‐grafted polyethylene‐octene elastomer), in PA matrix with twin screw extruder. The ratio of blending is 80PA/20TPU and 80PA/20TPU/20POE‐g‐MA (66.66PA/16.67TPU/16.67POE‐g‐MA). Results indicate that POE‐g‐MA improves the low viscosity of PA and TPU during the blending process, and also their compatibility. Thus, the 80PA/20TPU/20POE‐g‐MA blend has better tensile stress and elongation than 80PA/20TPU blend, and furthermore POE‐g‐MA significantly improves the impact strength of PA, even to super‐toughness grade. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010