Influence Of Compatibilizer Research Articles

Influence of compatibilizer on notched impact strength and fractography of HDPE-organoclay composites

The focus of this study was the notched impact property of high-density polyethylene (HDPE)–organoclay composites and the resultant morphology of impact-fractured surfaces. Composites with a different organoclay content and degree of organoclay dispersion were compared with neat HDPE under identical conditions. The degree of organoclay dispersion was controlled through the use of a compatibilizer, maleic anhydride grafted polyethylene. It was found that the addition of organoclay can slightly increase the elastic modulus and notched impact strength of the composite. When the level of organoclay dispersion was improved by using compatibilizer, elastic modulus and toughness further increased. A significant increase in yield strength was also notable. The presence of organoclay was found to suppress strain hardening of the matrix during tensile testing. The impact-fractured surfaces of failed specimens were studied with scanning electron microscopy. The micromechanism for the increased toughness of HDPE–organoclay composites was discussed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Influence of Compatibilizer on Morphology and Dynamic Rheological Behavior of Polyethylene-Octene Elastomer/Starch Blends

The morphology and rheology of polyethylene-octene elastomer (POE)/crosslinked starch (CS) immiscible blends with various amounts of compatibilizer were experimentally examined. A graft copolymer, POE-g-MAH, acting as the compatibilizer, was used to modify the interface of the blend. The particle radius in the POE/CS 80/20 system decreased with increasing compatibilizer up to 5 wt%, beyond which the particle size slightly increased. This indicates that the interface reaches saturation when the compatibilizer content is 5 wt%, leading to reduced effectiveness of the compatibilizer. From the SEM micrographs, the compatibilized blends were found to have better interfacial adhesion between the POE and starch phase than the uncompatibilized blends. Rheological examination shows a sharp reduction of the viscoelastic modulus and complex viscosity in blends containing 10 wt% compatibilizer. When the content of compatibilizer is less than 5 wt%, the viscoelastic modulus and complex viscosity of the blends increase with increasing the content of compatibilizer.

Influence of compatibilizers on the rheological, mechanical, and morphological properties of epoxidized natural rubber/polypropylene thermoplastic vulcanizates

AbstractIn polymeric materials combining desirable properties, compatibility between constituent components of incompatible blends is necessary. The influence of two types of blend compatibilizers, a graft copolymer of maleic anhydride and polypropylene (PP) and phenolic‐modified PP, on the rheological, mechanical, and morphological properties of epoxidized natural rubber/PP thermoplastic vulcanizates was investigated at varied concentrations. All properties improved in a range of loading levels of compatibilizers at 0–7.5 wt % of PP. This was attributed to a chemical interaction between the different phases caused by the functionalized compatibilizers. Increasing chemical interaction between interfaces improved the interfacial tension and led to a microscale size of the dispersion. A decreasing trend in the properties was observed at compatibilizer levels higher than 7.5 wt % of PP because of segregation, which led to a third blend component dispersed in the PP matrix. The compatibilizers behaved as lubricants in the polymer melt flow. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Flame retardant mechanism of polymer/clay nanocomposites based on polypropylene

The combustion behavior and thermal-oxidative degradation of polypropylene/clay nanocomposite has been studied in this paper. The influence of compatibilizer, alkylammonium, organoclay, protonic clay and pristine clay is considered, respectively. The decrease of heat release rate (HRR) is mainly due to the delay of thermal-oxidative decomposition of the composites. The active sites on clay layers can catalyze the initial decomposition and the ignition of the composites. On the other hand, the active sites can catalyze the formation of a protective coating char on the samples. Moreover, the active sites can catalyze the dehydrogenation and crosslinking of polymer chains. Accordingly, the thermal-oxidative stability is increased and HRR is decreased.

Influence of compatibilizer and processing conditions on the dispersion of nanoclay in a polypropylene matrix

Polypropylene/organoclay nanocomposites have been prepared via direct melt intercalation in an internal mixer. Maleic anhydride grafted polypropylene (PP-g-MA) was used as a compatibilizer to improve the dispersability of the clay. The structures of nanocomposites have been characterized by X-ray diffraction, transmission electron microscopy and rheometry in small amplitude oscillatory shear. The effects of concentration of PP-g-MA and processing parameters were investigated. Wide angle X-ray diffraction shows that the interlayer spacing increases with the concentration of PP-g-MA, but is not significantly influenced by processing conditions. The study of linear viscoelastic properties shows that the storage modulus G′ is very sensitive to the microstructure of the nanocomposite. A Carreau–Yasuda law with a yield stress is proposed to describe the rheological behavior of these materials. Applications to the twin screw extrusion process are also presented.

Photo-oxidative degradation of polypropylene/montmorillonite nanocomposites

The photo-oxidative behavior of the polypropylene (PP)/montmorillonite (MMT) nanocomposites and microcomposites has been investigated upon ultraviolet exposure using the technique of infrared spectroscopy. The rate of photo-oxidative degradation of PP/MMT nanocomposites is much faster than that of pure PP. The influence of pristine MMT, alkylammonium and compatibilizer were investigated, respectively. All these components can catalyze the photo-oxidation of PP matrix, in which the influence of compatibilizer and pristine MMT is primary. Moreover, the dispersion state of the clay particles in the polymer matrices has a little influence on the photo-oxidative degradation of polymer matrix. Consequently, an integrated catalysis mechanism of the photo-oxidative degradation of PP clay nanocomposite is proposed. It would provide benefit direction for the preparation and usage of polymer layered silicate nanocomposites (PLSN).

Effects of compatibilization of oxidized polypropylene on PP blends of PP/PA6 and PP/talc

AbstractThe influence of compatibilization on the dynamic mechanical properties of polypropylene (PP) binary blends with polyamide‐6 (PA6), Talc, and oxidized PP (OPP) was investigated. The oxidation of PP homopolymer was performed in a internal mixer by using air as a oxidizing agent (under atmospheric pressure) and dodecanol‐1 as an accelerator at 180°C for 6½ h [Abdouss, M.; Sharifi‐Sanjani, N.; Bataille, P. J Appl Polym Sci 1999, 36, 10]. In the blends, OPP was used as a blend component and compared with PP over the whole concentration range. Pressed film blends of PP/OPP, PP/OPP/Talc, and PP/OPP/PA6 were examined by dynamic mechanical analyzer, thermal gravimetry analysis, and scanning electron microscopy. Mechanical properties such as tensile strength, modulus of elasticity, elongation, melt flow index, and hardness of the blends were measured. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2871–2883, 2004

Polimerowo-oligomerowe kompozycje w powlokach lakierowych na przykladzie kompozycji polichlorowinylowo-epoksydowej

Compositions based on vinyl chloride/vinyl isobutyl ether copolymer (CVC) and epoxy oligomer (OE) showing the limited phase miscibility in the paint coatings were the subjects of investigations. Miscibility of the components in the presence of a solvent was measured using the method of determination of cloud-point of coatings. It has been found that OE content in the system more than 30 wt. % causes phase separation (Fig. 1, Table 1). Investigation of the influence of compatibilizers - melamine-formaldehyde oligomers (OMF) or chloroparaffin - showed the compatibilizers influenced phase miscibility and interface reinforcement different ways, dependently on their chemical structures. OMF favors the reinforcement of interface interaction via chemical bond what is confirmed by higher content of gel fraction (Table 2). The coatings prepared from the investigated compositions CVC/OE (also containing a compatibilizer) show often better mechanical and thermal properties than the coating prepared from the components (Table 3, 4).

Polyamide Reinforced EPDM Compatibilized with Maleic Anhydride Grafted Ethylene-Propylene-Diene Rubber

Vulcanizates of blends of ethylene-propylene-diene rubber (EPDM) and polyamide (PA) copolymer were prepared by reactive compatibilization. A reactive route was employed to compatibilize these blends by the addition of maleic anhydride EPDM (MAH-g-EPDM). In this paper, the influence of compatibilizers, crosslinking agents, and blend composition on the mechanical properties of the blends were investigated. The morphologies of the blends were determined by scanning electron microscopy. It was found that the addition of MAH-g-EPDM reduced the particle size of the dispersed phase remarkably. The stability of the blend was measured by thermal ageing at high temperature in the presence of compatibilizer. Both dynamic mechanical thermal analysis and differential scanning calorimetry experiments were carried out to investigate the effect of MAH-g-EPDM addition on the Tgs of the blend components. The addition of PA copolymer caused significant improvement in the tensile properties of these blends.

Formation of Co-continuous Structures in Melt-Mixed Immiscible Polymer Blends

Co-continuous structures can be regarded as the coexistence of at least two continuous structures within the same volume. Blends with co-continuous structures may combine the properties of both components in a favorable way, for example, mechanical moduli. This review article deals with the identification, characterization, and properties of co-continuous structures as well as with the development of co-continuous structures during the melt blending process. Co-continuous structures usually can be formed within a composition region about the phase inversion composition, which mainly depends on the viscosity ratio. On the other hand, co-continuous structures can be found independent of composition as intermediate stages during the initial state of morphology development and during phase inversion process in blends in which the component finally forming the dispersed phase forms the matrix in early mixing states. In addition, even at low volume fractions of one component, stable co-continuous morphologies can be created using suitable processing conditions, forming long elongated interconnected structures that do not break up because of the flow. The interfacial tension plays an important role for the stability; a lower interfacial tension leads to broader composition ranges of co-continuous structures. Another factor enhancing the formation and stability of co-continuous structure is melt yield stress of one or both components of blends. In addition, this article reviews the stability of co-continuous structures during further processing and the influence of compatibilization on the structure formation and stability. Subsequently, two models describing the co-continuous composition range are discussed.

Influence of compatibilizers on mechanical properties, crystallization, and morphology of polypropylene/scrap rubber dust blends

AbstractPolypropylene blends containing a dispersed phase of scrap rubber dusts obtained from sport shoes manufacture; midsole (M, vulcanized EVA foam) and outsole (O, vulcanized rubber blend of NR, SBR, and BR) were studied. The influence of various compatibilizers on the mechanical properties of these blends were investigated. Significant development of impact strength was attained by using 6 and 10 phr of styrene–ethylene–butylene–styrene (SEBS) and maleic anhydride‐grafted styrene–ethylene–butylene–styrene (SEBS‐g‐MA) as compatibilizers for both compounds filled with midsole and outsole dusts. The tensile strength of each compound was slightly decreased when the compatibilizer loading increased, whereas the elongation at break was significantly increased. The enhancements of the impact strength and the elongation at break are believed to arise from reduction of interfacial tension between two phases of the rubber and the PP, which results in some reduction of the particle size of the fillers. Scanning electron microscopy (SEM) confirmed the evidence of the reduction of scrap rubber dust into small rubber particle sizes in the compound, and also showed the occurrence of some fibrils. Optical microscopy (crossed polars) observations suggested that the addition of the rubber dust resulted in a less regular spherulite texture and less sharp spherulite boundaries. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 148–159, 2002

Influence of compatibilizers on the surface hardness, water uptake and the mechanical properties of poly(propylene) wood flour composites prepared by reactive extrusion

Anisotropic wood flour (WF) particles, composed of fiber bundles, were melt compounded in a twin screw extruder at 200°C together with poly(propylene) (PP) in the presence of maleic anhydride-grafted poly(propylene) (PP-g-MA) and maleic anhydride-grafted poly-(styrene)-block-poly(ethene-co-1-butene)-block-poly(styrene) (SEBS-g-MA). Mechanical properties, surface hardness, and water uptake were monitored as a function of compound composition and type of compatibilizer. PP/WF/SEBS-g-MA containing 30 vol.-% (40 wt.-%) WF and 3.5 vol.-% (3 wt.-%) SEBS-g-MA gave Shore hardness of 78 with respect to 70 for PP and increased simultaneously Young's modulus (100%), yield stress (20%) and notched Izod impact strength (24%). SEBS-g-MA compatibilizer addition did not affect the surface hardness but accounted for substantially reduced water uptake and excellent interfacial adhesion. In comparison to talcum-filled PP, PP/WF/SEBS-g-MA composites exhibited lower density combined with higher specific strength, specific Young's modulus, and higher surface hardness. WF particle as well as composite morphologies were imaged by means of enviromental scanning electron microscopy (ESEM).

Influence of compatibilization and viscosity ratio on the barrier and impact properties of blends of a modified polyamide‐6 and polyethylene

AbstractNylon 6 was grafted with a zinc‐neutralized ethylene/acrylic acid copolymer (CP) to produce four different modified polyamides (MPA) with varying CP content. These were mixed with four polyethylenes with different viscosities and the blends were blow‐molded into bottles. The clearest MPA lamina was developed for blends with an optimum ratio of the viscosities of MPA and PE (VRoptimum), and bottles with the clearest lamina exhibited the best xylene permeation resistance, impact strength and the highest melting temperature (Tm). The value of VRoptimum increased with increasing CP content. A maximum improvement in barrier properties of MPA was found as the CP content reached about 15 wt%. The CP content of the MPA, however, only slightly affected the impact strength and xylene permeation resistance of the bottles.

Polymer-Polymer Adhesion in the Presence of Compatibilizer

Abstract The influence of compatibilizers in three types of joints-natural rubber (NR)-polyethylene (PE), silicone rubber (Si)-ethylene propylene diene rubber (EPDM) and hydrogenated nitrile rubber (HNBR)-nylon has been demonstrated. The compatibilizers increase the peel strength in every case. The results are explained with the help of new approaches based on (1) strain energy density, (2) reptation scaling theory. It is observed that the diameter of the strained tip for NR-PE and Si-EPDM systems increases in the presence of compatibilizers. Also, the peel strength of the HNBR-nylon joint has a first power dependence on the interfacial thickness.

Influence of Compatibilizer and Additives on the Mechanical Properties of Polyethylene-Polystyrene Blends

Polymer blends were prepared based on three different types of LDPE (A.B.C) and polystyrene without or with compatibilizer (KRATON G-1652) and with the addition of a pigment Iriodin, for the improvement of the optical properties. The Brabender torque and the tensile properties of the polymer blends were determined, particularly, the yield stress σy, the ultimate tensile strength (e.g. the strength at break) σB and the ultimate elongation (elongation at break) εB. By factorial experimental design, factors A (proportion of LDPE/polystyrene) and B (proportion of compatibilizer) were found to be statistically significant while C (type of LDPE) has lower significance. The compatibilizer acts as a reinforcing agent in the polymer blend of LDPE and polystyrene, changing the stress-strain curve to a ductile behaviour, increasing the torque, σB and εB and decreasing σY. Graphite, which is contained in LDPE-A, acts as a reinforcing agent. Iriodin does not act as a reinforcing agent in the polymer blend but leads to a decrease of σB, and to an increase of torque. It does not influence the stress-strain curve much. The appropriate amount of compatibilizer is determined to be up to 20%. Iriodin improves the optical properties of polymer blends and compensates for their inferior mechanical properties.

Influence of Compatibilizer and Additives on the Mechanical Properties of Polyethylene-Polystyrene Blends

Polymer blends were prepared based on three different types of LDPE (A.B.C) and polystyrene without or with compatibilizer (KRATON G-1652) and with the addition of a pigment Iriodin, for the improvement of the optical properties. The Brabender torque and the tensile properties of the polymer blends were determined, particularly, the yield stress σy, the ultimate tensile strength (e.g. the strength at break) σB and the ultimate elongation (elongation at break) εB. By factorial experimental design, factors A (proportion of LDPE/polystyrene) and B (proportion of compatibilizer) were found to be statistically significant while C (type of LDPE) has lower significance. The compatibilizer acts as a reinforcing agent in the polymer blend of LDPE and polystyrene, changing the stress-strain curve to a ductile behaviour, increasing the torque, σB and εB and decreasing σY. Graphite, which is contained in LDPE-A, acts as a reinforcing agent. Iriodin does not act as a reinforcing agent in the polymer blend but leads to a decrease of σB, and to an increase of torque. It does not influence the stress-strain curve much. The appropriate amount of compatibilizer is determined to be up to 20%. Iriodin improves the optical properties of polymer blends and compensates for their inferior mechanical properties.

Dynamic mechanical properties of polypropylene–polyamide blends: Effect of compatibilization

AbstractThe influence of compatibilization on the dynamic mechanical properties of polypropylene (PP) binary blends with polyamide‐11 (PA) has been investigated. In the blends an acrylic acid functionized PP was used as a blend component and compared with nonfunctionized PP over the who concentration range. The results demonstrate that the use of the functionized PP instead of the unmodified one produced blends with different dynamic mechanical properties due to adhesion enhancement between the two phases. The storage moduli E′ of the compatibilized blends vary nearly linearly as a function of composition over a broad temperature region, whereas those of the noncompatibilized ones deviate greatly from linearity, specially at about 50/50 ratio, at which a minimum exists at about room temperature. While the dynamic testing gives no evidence for the variation in the glassy transition temperatures (peak maxima) of the components (PP and PA) in the two types of blends, both the loss modulus (E″) and the loss factor (tan δ) data indicate that the compatibilized blends differ from the noncompatibilized ones mainly in the glassy transition (βrelaxation) process of the PA phase, suggesting that the compatibilization of the blends seems to influence the PA phase more than the PP phase included. But, for the β‐relaxation behavior of the PA in the modified blends, the tan δ spectrum shows a more complex pattern than does the E″. These results are discussed in terms of the morphological texture of the blends and possible chemical or physical interactions between the two consituent polymers.

The effect of compatibilizer level on the mechanical properties of a nylon 6/ABS polymer blend

The influence of compatibilizer on the morphology and mechanical properties of a blend of nylon 6 and ABS has been studied. For this blend, the morphological domain size decreases significantly with increasing compatibilizer level. However, stiffness and tensile stress at yield are unaffected by these changes. Within the range of these experiments, lzod impact strength increases monotonically with increasing levels of compatibilizer, but the resistance to crack initiation (J c) and the resistance to steady state crack growth (R p) are both increased by the addition of a small amount of compatibilizer and are essentially independent of further increases.