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     

Effect of a hybrid compatibilizer on the mechanical properties and interfacial tension of a ternary blend with polypropylene,poly(lactic acid), and a toughening modifier

This study examined the effect of three compatibilizers, namely, a hybrid compatibilizer composed of polypropylene‐maleic anhydride (PP‐g‐MAH) and polyethylene‐glycidyl methacrylate (PE‐g‐GMA), a single compatibilizer composed of PP‐g‐MAH, and a single compatibilizer composed of PE‐g‐GMA, on the mechanical, morphological, and rheological properties of a ternary blend of polypropylene (PP), poly(lactic acid; PLA), and a toughening modifier. The results of tensile strength, flexural strength, and impact strength tests for the ternary blends before and after hydrolysis, revealed that the ternary blend with a hybrid compatibilizer content of 3 phr exhibited better material properties than the blend containing a single compatibilizer. In the weighted relaxation spectra of the ternary blend using the Palierne emulsion model, the ternary blend containing the hybrid compatibilizer, exhibited only one relaxation spectrum peak at ∼ 0.16 s. This result suggests that the ternary blend with the hybrid compatibilizer exhibits uncharacteristic morphological properties, that is, a single‐phase microstructure. The above results suggest that the hybrid mixture is an effective compatibilizer for the ternary blend of PP, PLA, and a toughening modifier. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers     

Effect of blend ratio on bulk properties and matrix-fibril morphology of polypropylene/nylon 6 polyblend fibers

Ternary blends of polypropylene (PP), nylon 6 (N6) and polypropylene grafted with maleic anhydride (PP/N6/PP-g-MAH) as compatibilizer with up to 50 wt% of N6 were investigated. PP-g-MAH content was varied from 2.5 to 10%. Blends of the two polymers PP/N6 (80/20) without the compatibilizer were also prepared using an internal batch mixer and studied. The ternary blends showed different rheological properties at low and high shear rates. The difference depended on the amount of N6 dispersed phase. Co-continuous morphology was observed for the blend containing 50% N6. This blend also exhibited higher viscosity at low shear rate and lower viscosity at high shear rates than the value calculated by the simple rule of mixture. At higher shear rates, viscosity was lower than that given by the rule of mixture for all blend ratios. An increase in viscosity was observed in the 80/20 PP/N6 blend after the concentration of the interfacial agent (PP-g-MAH) was increased. Polyblends containing up to 30% N6 could be successfully melt spun into fibers. DSC results showed that dispersed and matrix phases in the fiber maintained crystallinity comparable to or better than the corresponding values found in the neat fibers. The dispersed phase was found to contain fibrils. By using SEM and LSCM analyses we were able to show that the N6 droplets coalesced during melt spinning which led to the development of fibrillar morphology.     

Morphology and properties of blends of polypropylene with ethylene-propylene rubber

Great attention has been paid to the toughening of isotactic polypropylene (PP) in recent years in order to make full use of this plastic. This paper presents the results of our study on the compatibility of PP with ethylene-propylene-diene rubber (EPT), polybutadiene rubber (PB) or styrene-butadiene rubber (SBR) through characterization of the blends' morphology, and on. the morphology and properties of binary blends of PP with EPT (EPT/PP) and ternary blends of PP, EPT, and polyethylene (PE) (EPT/PE/PP). Morphological structure of solution blends and the great improvement in low-temperature impact strength and other properties of the mechanical blends have shown the difference among EPT, PB, and SBR in compatibility with PP, the effectiveness of using EPT as PP's toughening agent, and the effect of EPT on EPT/PP blend as both toughening agent and compatibilizer. Addition of EPT to EPT/PP made interesting changes in morphology but no effect on properties was observed.     

Mechanical and Morphological Properties of Polypropylene and Regenerated Tire-Rubber Blends

Mechanical properties and morphology of blends prepared from polypropylene (PP) and 5–20 wt% of regenerated tire-rubber (RgR) were studied. The samples were prepared in a twin-screw extruder. The addition of maleic anhydride-functionalized polypropylene (PP-g-MAH) was also investigated. Tensile and flexural moduli, tensile strength at break, elongation at break and Izod impact resistance at 23°C were increased by the addition of 15 wt% of regenerated rubber and 5 wt% of PP-g-MAH. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) analyses showed some interaction between PP and RgR and considerable modification of the compatibilized mixture morphology. The fracture surface of the blend with PP-g-MAH showed a better interaction between the PP matrix and the regenerated rubber domains, for all blends. Well-dispersed particles of the rubber in the polypropylene matrix were observed. DSC showed that PP crystallizes on cooling at lower temperatures as the RgR content increases. The decrease in crystallization temperature is more evident for blends with 5 wt% PP-g-MAH.     

Blends of recycled polycarbonate and acrylonitrile–butadiene–styrene: comparing the effect of reactive compatibilizers on mechanical and morphological properties

Blends of recycled polycarbonate (PC) and acrylonitrile–butadiene–styrene (ABS) were prepared and some mechanical and morphological properties were investigated. To compatibilize these blends, ABS‐g‐(maleic anhydride) (ABS‐g‐MA) and (ethylene–vinyl acetate)‐g‐(maleic anhydride) (EVA‐g‐MA) with similar degree of grafting of 1.5% were used. To compare the effect of the type of compatibilizer on mechanical properties, blends were prepared using 3, 5 and 10 phr of each compatibilizer. A co‐rotating twin‐screw extruder was used for blending. The results showed that ABS‐g‐MA had no significant effect on the tensile strength of the blends while EVA‐g‐MA decreased the tensile strength, the maximum decrease being about 9.6% when using 10 phr of this compatibilizer. The results of notched Charpy impact strength tests showed that EVA‐g‐MA increased the impact strength of blends more than ABS‐g‐MA. The maximum value of this increase occurred when using 5 phr of each compatibilizer, it being about 54% for ABS‐g‐MA and 165% for EVA‐g‐MA. Scanning electron microscopy micrographs showed that the particle size of the dispersed phase was decreased in the continuous phase of PC by using the compatibilizers. Moreover, a blend without compatibilizer showed brittle behaviour while the blends containing compatibilizer showed ductile behaviour in fracture. © 2013 Society of Chemical Industry     

Dynamic reaction inside co‐rotating twin screw extruder. II. Waste ground rubber tire powder/polypropylene blends

In this article, dynamic reaction of waste ground rubber tire powder/PP blends with compatibilizers is extended to commercially available waste rubber Viz. Ground rubber tire and PP for the possibility of getting recycled material with good mechanical properties. In the first part of the article it was shown that the compatibility of model material/PP blends has greatly improved. In this article, extensive studies have been carried out to study the effect of compatibilizers, in‐situ compatibilization of immiscible waste ground rubber tire (WGRT) powder/polyolefin blends of various concentrations was investigated by means of extrusion process using a co‐rotating twin screw extruder. It was observed that addition of small amounts of compatibilizers like SEBS‐g‐MA to the blends of WGRT and PP‐g‐MA can result in better mechanical properties than the blends with isotactic PP. The blends of WGRT powder and PP‐g‐MA with compatibilizer have better adhesion than those of isotactic PP blends as revealed by the morphological studies using AFM and SEM. The betterment in properties can be attributed to the presence of functional group, maleic anhydride in PP‐g‐MA. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Compatibilizers for recycling of the plastic mixture wastes. II. The effect of a compatibilizer for binary blends on the properties of ternary blends

In this article, we discuss the effect of a compatibilizer for binary blends on the properties of ternary blends composed of high‐density polyethylene (HDPE), polypropylene (PP), or polystyrene (PS) and poly(vinyl chloride) (PVC) virgin polymers with a simulated waste plastics fraction. Chlorinated polyethylene (CPE), ethylene–propylene rubber (EPR), and their 1/1 (w/w) mixture were tested as compatibilizers for the HDPE/PP/PVC ternary blend. CPE, styrene‐ethylene‐propylene block copolymer (SEP), or their 1/1 (w/w) mixture were tested as compatibilizers for the HDPE/PS/PVC ternary blend. The composition of the ternary blends were fixed at 8/1/1 by weight ratio. The amount of the compatibilizer was 3 phr. Rheological, mechanical, and thermal properties were measured. For the 8/1/1 HDPE/PP/PVC ternary blends, the tensile strength was slightly decreased, but the impact strength was significantly increased by adding EPR, CPE, or their mixture. EPR exhibited the most significant impact modification effect for the ternary blends. In a similar way, for 8/1/1 HDPE/PS/PVC ternary blends, on adding SEP, CPE, or their mixture, the tensile strength was slightly decreased, but the impact strength was noticeably increased. It was found that the SEP worked much better as an impact modifier for the ternary blends than CPE or the SEP/CPE mixture did. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1048–1053, 2000     

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.     

Thermoplastic vulcanizates based on epoxidized natural rubber/polypropylene blends: Effect of compatibilizers and reactive blending

Epoxidized natural rubber (ENR) was prepared using the performic epoxidation method. TPVs based on ENR/PP blends were later prepared by melt‐mixing processes via dynamic vulcanization. The effects of blend ratios of ENR/PP, types of compatibilizers, and reactive blending were investigated. Phenolic modified polypropylene (Ph‐PP) and graft copolymer of maleic anhydride on polypropylene molecules (PP‐g‐MA) were prepared and used as blend compatibilizers and reactive blending components of ENR/Ph‐PP and ENR/PP‐g‐MA blends. It was found that the mixing torque, apparent shear stress and apparent shear viscosity increased with increasing levels of ENR. This is attributed to the higher viscosity of the pure ENR than that of the pure PP. Furthermore, there was a higher compatibilizing effect because of the chemical interaction between the polar groups in ENR and PP‐g‐MA or Ph‐PP. Mixing torque, shear flow properties (i.e., shear stress and shear viscosity) and mechanical properties (i.e., tensile strength, elongation at break, and hardness) of the TPVs prepared by reactive blending of ENR/Ph‐PP and ENR/PP‐g‐MA were lower than that of the samples without a compatibilizer. However, the TPVs prepared using Ph‐PP and PP‐g‐MA as compatibilizers exhibited higher values. We observed that the TPVs prepared from ENR/PP with Ph‐PP as a compatibilizer gave the highest rheological and mechanical properties, while the reactive blending of ENR/PP exhibited the lowest values. Trend of the properties corresponds to the morphology of the TPVs. That is, the TPV with Ph‐PP as a blend compatibilizer showed the smallest rubber particles dispersed in the PP matrix, while the reactive blending of ENR/PP‐g‐MA showed the largest particles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4729–4740, 2006     

Compatibilization of polyethylene terephthalate/polypropylene blends with styrene–ethylene/butylene–styrene (SEBS) block copolymers

Blends of polyethylene terephthalate (PET) and polypropylene (PP) at compositions 20/80 and 80/20 were modified with three different styrene–ethylene/butyl–ene-styrene (SEBS) triblock copolymers with the aim of improving the compatibility and in particular the toughness of the blends. The compatibilizers involved an unfunctionalized SEBS and two functionalized grades containing either maleic anhydride (SEBS-g-MAH) or glycidyl methacrylate (SEBS-g-GMA) grafted to the midblock. The effects of the compatibilizers were evaluated by studies on morphology and mechanical, thermal and rheological properties of the blends. The additon of 5 wt % of a SEBS copolymer was found to stabilize the blend morphology and to improve the impact strength. The effect was, however, far more pronounced with the functionalized copolymers. Particularly high toughness combined with rather high stiffness was achieved with SEBS-g-GMA for the PET-rich composition. Addition of the functionalized SEBS copolymers resulted in a finer dispersion of the minor phase and clearly improved interfacial adhesion. Shifts in the glass transition temperature of the PET phase and increase in the melt viscosity of the compatibilized blends indicated enhanced interactions between the discrete PET and PP phases induced by the functionalized compatibilizer, in particular SEBS-g-GMA. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:241–249, 1997     

Evaluation of polypropylene grafted with maleic anhydride and styrene as a compatibilizer for polypropylene/clay nanocomposites

Among modified Poly(propylene)s (PPs) grafted with polar monomers, PP grafted with maleic anhydride (PP-g-MAH) is known to be the most efficient compatibilizer for PP/clay nanocomposites, since it provides well-dispersed nanostructures and yields optimal physical properties of the nanocomposites. One drawback of this material, however, is that it becomes brittle and its viscosity decreases drastically, leading to nanocomposites with low toughness as the graft degree of MAH increases. Therefore, there is a limitation to increasing both stiffness and toughness of PP/clay nanocomposites with PP-g-MAH. In this study, we investigated the performance of a PP grafted with maleic anhydride and styrene (PP-g-MAH-St) as compatibilizers in PP/clay nanocomposites. It was found that the incorporation of styrene as a comonomer prevents molecular weight reduction of the PP main chain upon high loading of a radical initiator for high graft degree of MAH. The compatibilizers (PP-g-MAH-St) thus obtained show good compatibilizing performance in PP/clay nanocomposites. The PP/clay nanocomposites compatibilized by PP-g-MAH-St show both high stiffness and toughness, which is accomplished by using a compatibilizer of higher viscosity compared with PP-g-MAH.     

Rheological,thermal, and morphological properties of blends based on poly(propylene), ethylene propylene rubber,and ethylene-1-octene copolymer that could result from end of life vehicles: Effect of maleic anhydride grafted poly(propylene)

The objective of this work is to study the properties of blends that could result from the recycling of end-of-life vehicles (ELV). While ethylene propylene rubber (EPR) and ethylene propylene diene monomer (EPDM) have been used extensively as elastomeric additives in poly(propylene) (PP), they can be substituted by ethylene-1-octene copolymer (EOC). As a consequence, the matter resulting from the sorting of ELV might be more complex and made of PP, EPR, and EOC. The effect of incorporating EOC [that is a polyethylene elastomer (PEE)] and maleic anhydride grafted polypropylene (PP-g-MAH) on the rheological, thermal, and morphological properties of PP/EPR blends has been investigated. Blends of various compositions (with and without compatibilizer) were prepared using a corotating twin-screw extruder. The results were compared to the ones presented by a commercial (PP/EPR) blend. The EPR phase is dispersed in the form of spherical particles in (PP/EPR). The EOC phase is dispersed in the form of aggregated particles. Dynamic viscoelastic and differential scanning calorimetry properties of (PP/EPR)/EOC blends shows the incompatibility of the components even in presence of PP-g-MAH copolymer. POLYM. ENG. SCI., 47:1009–1015, 2007. © 2007 Society of Plastics Engineers     

Effect of compatibilizer on the crystallization,rheological, and tensile properties of LDPE/EVOH blends

The effect of the compatibilizer on the crystallization, rheological, and tensile properties of low-density polyethylene (LDPE)/ethylene vinyl alcohol (EVOH) (70/30) blends was investigated. Maleic anhydride-grafted linear low-density polyethylene (LLD-g-MAH) was used as the compatibilizer in various concentrations (from 1 to 12 phr). The interesting effect of compatibilization on the crystallization kinetics of the blends was noted, and the correlation between the morphology and the rheological and tensile properties was also discussed. Morphological analysis showed that the blends exhibited a regular and finer dispersion of the EVOH phase when LLD-g-MAH was added. Nonisothermal crystallization exotherms of the compatibilized LDPE/EVOH blends showed the retarded crystallization of the dispersed EVOH phase, which probably resulted from the constraint effect of the grafted EVOH (EVOH-g-LLD) as well as the size reduction of the EVOH domains. The blends exhibited increased melt viscosity and storage modulus and also enhanced tensile properties with the addition of LLD-g-MAH, which seemed to be attributable to both dispersed particle-size reduction and improved interfacial adhesion. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1245–1256, 1998     

The effect of compatibilizers and organically modified nanoclay on the morphology and performance properties of poly(acrylonitrile–butadiene–styrene)/polypropylene blends

In this study, poly(acrylonitrile–butadiene–styrene)/polypropylene (ABS/PP) blends with various compositions were prepared by melt intercalation in a twin‐screw extruder. Modifications of the above blends were performed by using organically modified montmorillonite (OMMT, Cloisite 30B) reinforcement as well as two types of compatibilizers, namely polypropylene grafted with maleic anhydride (PP‐g‐MAH) and ABS grafted with maleic anhydride (ABS‐g‐MAH). Increasing the PP content in ABS matrix seems to increase the melt flow and thermal stability of their blends, whereas a deterioration of the tensile properties was recorded. On the other hand, the addition of ABS to PP promotes the formation of the β‐crystalline phase, which became maximum at 30 wt% ABS concentration, and increases the crystallization temperature (T_c) of PP. A tendency for increase of T_c was also recorded by incorporation of the above compatibilizers, whereas the glass transition temperature (T_g) of PP and SAN phase in ABS was reduced. Regarding the Young's modulus, the greatest improvement was observed in pure ABS/PP blends containing organically modified nanoclay. However, in reinforced pure PP, the use of compatibilizers is recommended in order to improve the elastic modulus. The addition of OMMT to noncompatibilized and compatibilized ABS/PP blends significantly improves their storage modulus. POLYM. ENG. SCI., 56:458–468, 2016. © 2016 Society of Plastics Engineers     

Isotactic polypropylene toughened with poly(acrylonitrile–butadiene–styrene): Compatibilizing role of maleic anhydride grafted polypropylene

The β‐nucleating activity and toughening effect of acrylonitrile–butadiene–styrene (ABS) graft copolymer on isotactic polypropylene (iPP) and the compatibilizing role of maleic anhydride grafted polypropylene (PP‐g‐MAH) on the iPP/ABS blends were investigated. The results show that ABS can induce the formation of β‐crystal in iPP, and its β‐nucleating efficiency depends on its concentration and dispersibility. The relative content of β‐crystal form is up to 36.19% with the addition of 2% ABS. The tensile and impact properties of the iPP were dramatically enhanced by introducing ABS. The incorporation of PP‐g‐MAH into the iPP/ABS blends inhibits the formation of β‐crystal. The crystallization peaks of the blends shift toward higher temperature, due to the heterogeneous nucleation effect of PP‐g‐MAH on iPP. The toughness of iPP/ABS blends improved due to favorable interfacial interaction resulting from the compatibilization of PP‐g‐MAH is significantly better than the β‐crystal toughening effect induced by ABS. POLYM. ENG. SCI., 59:E317–E326, 2019. © 2019 Society of Plastics Engineers     

Studies on binary and ternary blends of polypropylene with ABS and LDPE. II. Impact and tensile properties

Studies on impact and tensile properties of binary blend of PP and ABS and ternary blend of PP, ABS, and LDPE are presented. Variation of impact strength and the fracture surface morphology with blend composition is examined and interpreted. Tensile behavior in the yield region is studied and the trends of variation of work of yield and impact strength are compared to ascertain the predominent mechanism of impact toughening in these binary and ternary blends. An analysis of yield–stress data in terms of theoretical models is presented to reveal the differences in these binary and ternary blends, attributable to the role of LDPE component in the ternary blend.     

Novel strategy for ternary polymer blend compatibilization

A novel strategy for compatibilization of ternary polymer blends was described. PP (polyolefins)/PA6 (engineering plastics)/PS (styrene polymers) was selected as a model ternary blend system, and the compatibilization effect was investigated by means of SEM, rheometer, dynamic mechanical thermal analysis and mechanical testing. The results indicated that, as a ternary polymer blend compatibilizer, styrene and maleic anhydride dual monomers melt grafted polypropylene [PP-g-(MAH-co-St)] showed more effective compatibilization in the PP/PA6/PS ternary blend system than PP-g-MAH, PP-g-St and their mixture. The good compatibilizing effect of PP-g-(MAH-co-St) can be explained by two mechanisms. One is the in situ formation of [PP-g-(MAH-co-St)]-g-PA6 copolymer at the PP/PA6 interface, and the other is that it also contains styrene blocks, resulting in chemical affinity with PS and PP homopolymers.     

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     

The Effect of Multiple Compatibilizers on the Impact Properties of Polypropylene/Polystyrene (PP/PS) Blend

Effects of compatibilizers on impact properties of polypropylene/ polystyrene (PP/PS) blends were studied and carried out through melt blending using co- rotating twin-screw extruder. A combination of two compatibilizers, maleic anhydride grafted polypropylene (PP-g-MA) and styrene maleic anhydride (SMA) was applied into PP/PS blends. Results from the Izod impact strengths, SEM observations and contact angle measurements in PP(50)/PS(50) blends indicated a better compatibilization effect with the use of dual compatibilizers. This was most probably due to improved adhesion between phases in PP/PS blend systems. The use of dual compatibilizers in the blend compositions produced higher impact properties in the PP/PS blend systems compared to single compatibilizer system.