Reactive compatibilization of the poly(ethylene terephthalate)/liquid crystalline polymer blends by solid epoxy resin as a coupling agent

A selected reactive coupling agent can be served as an effective compatibilizer for certain immiscible and incompatible blends should both blend constituents possess the necessary functional groups that can react with the coupling agent at comparable rates. Solid epoxy resin with two epoxide endgroups per molecule was demonstrated to be an efficient reactive compatibilizer for the incompatible blends of poly(ethylene terephthalate) (PET) and copolyester liquid crystalline polymer (LCP) by functioning as a coupling agent. The main chain structure of the epoxy resin is neither identical not miscible with PET and LCP and tends to reside at interface during melt mixing. This preferential residence gives the epoxy compatibilizer greater opportunity to react with both PET and LCP simultaneously to produce the in situ–formed epoxy-b-LCP mixed copolymer. This in situ–formed mixed copolymer is highly effective in compatibilizing the PET/LCP blends. This reactive epoxy compatibilizer enhances the LCP fibril formation and results in substantial improvements on stiffness and toughness of the PET/LCP blends. © 1996 John Wiley & Sons, Inc.     

Melt blending of linear low-density polyethylene and polystyrene in a Haake internal mixer. II. Morphology-processing relationships

A measure of the effective shear rate range for dispersive mixing in the Haake mixer has been developed, which is more representative of shearing conditions than that currently used. In addition, the effects of processing conditions, composition, and compatibilizer on linear low-density polyethylene and polystyrene (LLDPE/PS) blend morphology were studied. Fiber/stratified morphologies form with blends when the minor phase has low viscosity and is present at its higher concentration. The influence of the viscosity ratio on phase size was found to be a minor effect for mixtures having a low fraction of the dispersed phase (20% PS). The effect of shear intensity, however, was found to be more important at a low composition of the dispersed phase or in compatibilized blends. During Haake blending, an optimal time for adding compatibilizer to stabilize phase morphology was found to be when the final morphology of an incompatible blend had developed. Further studies have concluded that the addition of styrene–ethylene/butylene–styrene (SEBS) stabilized the blend morphology of LLDPE/PS more efficiently than styrene–ethylene/propylene (SEP) on different blending conditions and compositions. At high temperatures, the addition of SEP to a LLDPE/PS blend did not modify the dispersed phase size. On the other hand, SEBS stabilized the dispersion so that the final domain size is independent of composition. © 1995 John Wiley & Sons, Inc.     

Interfacial adhesion reaction of polyethylene and starch blends using maleated polyethylene reactive compatibilizer

The interfacial reaction of the polyethylene (PE)/starch blend system containing the reactive compatibilizer maleated polyethylene (m‐PE) was directly characterized by Fourier transform infrared (FTIR) spectroscopy. A significant amount of anhydride groups on m‐PE existed as hydrolyzed forms, resulting in a large amount of carboxyl groups. Using a vacuum‐heating‐cell designed in the laboratory, the carboxyl groups were successfully transformed into the dehydrolyzed state (i.e., anhydride group). This result enabled the direct spectroscopic observation of chemical reaction occurring at the interface. For the PE/starch blend system containing m‐PE, the chemical reaction at the interface was verified by the evolution of ester and carboxyl groups in the FTIR spectra. The effect of the reactive compatibilizer on the interfacial morphology was also examined by scanning electron micrography (SEM). Enhanced interfacial adhesion was clearly observed for the blend system containing reactive compatibilizer. Tensile strengths of blend systems containing m‐PE also increased noticeably compared with the corresponding system without compatibilizer. A similar observation was made for the breaking elongation data. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 767–776, 2002     

Acrylonitrile–butadiene–styrene toughened nylon 6: The influences of compatibilizer on morphology and impact properties

Polymer alloys have been used as an alternative to obtain polymeric materials with unique physical properties. Generally, the polymer mixture is incompatible, which makes it necessary to use a compatibilizer to improve the interfacial adhesion. Nylon 6 (PA6) is an attractive polymer to use in engineering applications, but it has processing instability and relatively low notched impact strength. In this study, the acrylonitrile–butadiene–styrene (ABS) triblock copolymer was used as an impact modifier for PA6. Poly(methyl methacrylate‐co‐maleic anyhydride) (MMA‐MA) and poly(methyl methacrylate‐co‐glycidyl methacrylate) (MMA‐GMA) were used as compatibilizers for this blend. The morphology and impact strength of the blends were evaluated as a function of blend composition and the presence of compatibilizers. The blends compatibilized with maleated copolymer exhibited an impact strength up to 800 J/m and a morphology with ABS domains more efi8ciently dispersed. Moderate amounts of MA functionality in the compatibilizer (～5%) and small amounts of compatibilizer in the blend (～5%) appear sufficient to improve the impact properties and ABS dispersion. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 842–847, 2003     

Relationship between the interfacial tension and compatibility of polycarbonate and poly(acrylonitrile–butadiene–styrene) blends with reactive compatibilizers

We studied the morphological, mechanical, and rheological properties of polycarbonate (PC) and poly(acrylonitrile–butadiene–styrene) (PolyABS) blends with different types of compatibilizer. Styrene–acrylonitrile–maleic anhydride terpolymer (SAM) was used as a compatibilizer of the blends. For comparison, styrene–acrylonitrile–glycidyl methacrylate terpolymer (SAG) was also used as a compatibilizer. For the PC–PolyABS (70/30 wt %) blends with SAM, the mechanical strength and complex viscosity reached a maximum when the SAM concentration was 5 phr. The mechanical and rheological results of the blend were consistent with the morphological result that the PolyABS domain size reached a minimum when the SAM content was 5 phr. The interfacial tension (α) of the blend was compared with the compatibilizer type and content, which were calculated by the Palierne emulsion model with the relaxation time of the PC–PolyABS blend. The α is consistent with the morphological and mechanical properties of the PC–PolyABS blend. The results of the morphological, mechanical, and rheological properties of the blend suggest that SAM was a more effective compatibilizer than SAG, and the optimum compatibilizer content of SAM was 5 phr. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46418.     

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     

Amphiphilic styrene–butadiene–styrene triblock copolymer grafted with polyoxyethylene

A styrene–butadiene–styrene triblock copolymer (SBS) was grafted with polyoxyethylene via a ring‐opening reaction of an epoxidized styrene–butadiene– styrene triblock copolymer (ESBS) with monocarboxylic‐group‐terminated methoxypoly(ethylene glycol) (CMPEG). The latter was prepared through the esterification of methoxypoly(ethylene glycol) with maleic anhydride. The optimum conditions for the preparation of the graft copolymer were studied. The graft copolymer was characterized with Fourier transform infrared spectrophotometry. Its water absorbency, oil absorbency, emulsifying property, phase‐transfer catalysis property in the Williamson solid–liquid reaction, and use as a compatibilizer in the blending of SBS with oil‐resistant chlorohydrin rubber (CHR) were also studied. The optimum conditions were a CMPEG/epoxy group molar ratio of 1.5, an N,N‐dimethyl aniline/ESBS concentration of 5 wt %, and an ESBS concentration of 12–14 g/100 mL at 75–80°C for 10 h. The polyoxyethylene content could reach 0.27 mmol/g. The graft copolymer absorbed a certain amount of water, fairly resisted kerosene, and possessed good emulsifying and phase‐transfer catalysis properties, both of which were enhanced with increasing polyoxyethylene graft content. The graft copolymer could be used as a compatibilizer for a blend of SBS and CHR. A 3 wt % concentration of the graft copolymer based on a 50/50 blend could increase both the tensile strength and ultimate elongation of the blend about 1.7 times. The blend behaved like an oil‐resistant thermoplastic elastomer. Scanning electron microscopy demonstrated the improved compatibility of the two components by the graft copolymer. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Behavior of ionomers of sulfonated styrene–butadiene–styrene triblock copolymer in polymer blends with crystalline polyolefins and as compatibilizer

The blends of ionomers of sulfonated (styrene–butadiene–styrene) triblock copolymer with two polyolefins as well as the blends of polystyrene (PSt) with two polar, oil‐resistant elastomers, i.e., chlorohydrin rubber (CHR) and chlorosulfonated polyethylene (CSPE), using the ionomer as compatibilizer were studied. The blends of the ionomer with polypropylene or high density polyethylene showed synergistic effects with respect to tensile strength. With increasing PSt content, the blends change their behavior from thermoplastic elastomer to toughened plastics. The synergism is probably because of the thermoplastic interpenetrating polymer networks formed in the blend. The blends exhibited high resistance against diesel oil or toluene. When PSt was blended with CHR or CSPE using the ionomer as compatibilizer, only 2 or 3% ionomer was needed to enhance the mechanical properties of the blends. The effect is due to the ion–polar interaction of the ionomer with the polar polymer. The enhanced compatibility of the blends by the ionomer was demonstrated by DSC and Scanning electron micrograph. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1887–1894, 2006     

Effect of triblock copolymers on homogeneity,mechanical properties and swelling behavior of IIR/SBR rubber blends

The present research concerns with the preparation and characterization of isobutylene isoprene/butadiene–styrene rubber (IIR/SBR) blends with different blend ratios, in the presence and absence of styrene–isoprene–styrene (SIS) and styrene–isobutylene–styrene (SiBS) triblock copolymers to be tested as compatibilizers. Effect of the triblock copolymers on the blend homogeneity was investigated with the aid of scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) measurements. Characterization of the rubber blends was conducted by measuring the physico-mechanical properties after and before thermal aging, in presence and absence of the triblock copolymers. In addition, weight swell % in toluene, motor oil and brake fluid of the rubber blend vulcanizates was assessed. The incorporation of SIS and SiBS triblock copolymers improved the homogeneity of IIR/SBR blends as well as increased both tensile strength and elongation at break of the rubber blend vulcanizates. Of the entire blend ratios examined, IIR/SBR (25/75) blend containing SIS compatibilizer possessed the best physico-mechanical properties (12.6 MPa tensile strength and 425 % elongation at break) and (14 MPa tensile strength and 555 % elongation at break) after and before thermal aging, respectively. Utilization of SIS and SiBS triblock copolymers enhanced the thermal stability of IIR/SBR blend vulcanizates. Moreover, IIR/SBR blends of different blend ratios showed superior swelling resistance in the brake fluid. IIR/SBR (25/75) blend containing SIS compatibilizer and cured with CBS/ZDEC/S vulcanizing system possessed the best physico-mechanical properties (14.4 MPa tensile strength and 440 % elongation at break) and (16.5 MPa tensile strength and 610 % elongation at break) after and before thermal aging, respectively.     

Effects of mixing protocol on the performance of nanocomposites based on polyamide 6/acrylonitrile–butadiene–styrene blends

Toughening of polyamide 6 (PA6) can be achieved by appropriate addition of an elastomeric matrix phase; however, this leads to a loss of rigidity and mechanical strength. As a result, much research has been directed at obtaining an optimal balance between toughness and rigidity for these thermoplastics. The approach explored here is the formation of nanocomposites from PA6/acrylonitrile–butadiene–styrene (ABS) blends prepared by melt mixing with a modified montmorillonite (Cloisite® 30B) and styrene/maleic anhydride copolymer as a compatibilizer. The effect of the mixing sequence of the components on the morphology and properties is a primary focus. The morphology and mechanical properties of the materials were characterized by X‐ray diffraction, electron microscopy, and tensile and impact testing. Incorporation of the compatibilizer in the PA6/ABS blend increased toughness but decreased rigidity. A significant increase of modulus was observed for the nanocomposite blend compared with the blend or the matrix. This increase was attributed to the exfoliation of organoclay layers in the PA6 matrix phase. It was also observed that the morphology of the ABS dispersed phase was considerably influenced by the mixture sequence. POLYM. ENG. SCI., 52:1909–1919, 2012. © 2012 Society of Plastics Engineers     

Properties of acrylonitrile–butadiene–styrene/polycarbonate blends with styrene–butadiene–styrene block copolymer

The importance of alloys and blends has increased gradually in the polymer industry so that the plastics industry has moved toward complex systems. The main reasons for making polymer blends are the strengthening and the economic aspects of the resultant product. In this study, I attempted to improve compatibility in a polymer blend composed of two normally incompatible constituents, namely, acrylonitrile–butadiene–styrene (ABS) and polycarbonate (PC), through the addition of a compatibilizer. The compatibilizing agent, styrene–butadiene–styrene block copolymer (SBS), was added to the polymer blend in ratios of 1, 5, and 10% with a twin‐screw extruder. The morphology and the compatibility of the mixtures were examined by scanning electron microscopy and differential scanning calorimetry. Further, all three blends of ABS/PC/SBS were subjected to examination to obtain their yield and tensile strengths, elasticity modulus, percentage elongation, Izod impact strength, hardness, heat deflection temperature, Vicat softening point, and melt flow index. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2521–2527, 2004     

Effects of olefin‐based compatibilizers on the morphology,thermal and mechanical properties of ABS/polyamide‐6 blends

In this study, commercially available epoxidized and maleated olefinic copolymers, EMA‐GMA (ethylene‐methyl acrylate‐glycidyl methacrylate) and EnBACO‐MAH (ethylene‐n butyl acrylate‐carbon monoxide‐maleic anhydride), were used at 0, 5, and 10% by weight to compatibilize the blend composed of ABS (acrylonitrile‐butadiene‐styrene) terpolymer and PA6 (polyamide 6). Compatibilizing performance of these two olefinic polymers was investigated from blend morphologies, thermal and mechanical properties as a function of blend composition, and compatibilizer loading level. Scanning electron microscopy (SEM) studies showed that incorporation of compatibilizer resulted in a fine morphology with reduced dispersed particle diameter at the presence of 5% compatibilizer. The crystallization behavior of PA6 phase in the blends was explored for selected blend compositions by differential scanning calorimetry (DSC). At high compatibilizer level a decrease in the degree of crystallization was observed. In 10% compatibilizer containing blends, formation of γ‐crystals was observed contrary to other compatibilizer compositions. The behavior of the compatibilized blend system in tensile testing showed the negative effect of using excess compatibilizer. Different trends in yield strengths and strain at break values were observed depending on compatibilizer type, loading level, and blend composition. With 5% EnBACO‐MAH, the blend toughness was observed to be the highest at room temperature. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 926–935, 2007     

Interface modification of compatibilized polyethylene terephthalate/polypropylene blends: Effect of compatibilization on thermomechanical properties and thermal stability

Polyethylene terephthalate (PET) and polypropylene (PP) are incompatible thermoplastics because of differences in chemical structure and polarity, hence their blends possess inferior mechanical and thermal properties. Compatibilization with a suitable block/graft copolymer is one way to improve the mechanical and thermal properties of the PET/PP blend. In this study, the toughness, dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA) of PET/PP blends were investigated as a function of different content of styrene‐ethylene‐butylene‐styrene‐g‐maleic anhydride (SEBS‐g‐MAH) compatibilizer. PET, PP, and SEBS‐g‐MAH were melt‐blended in a single step using the counter rotating twin screw extruder with compatibilizer concentrations of 0, 5, 10, and 15 phr, respectively. The impact strength of compatibilized blend with 10 phr SEBS‐g‐MAH increased by 300% compared to the uncompatibilized blend. Scanning electron microscope (SEM) micrographs show that the addition of 10 phr SEBS‐g‐MAH compatibilizer into the PET/PP blends decreased the particle size of the dispersed PP phase to the minimum level. The improvement of the storage modulus and the decrease in the glass transition temperature of the PET phase indicated an interaction among the blend components. Thermal stability of the PET/PP blends was significantly improved because of the addition of SEBS‐g‐MAH. J. VINYL ADDIT. TECHNOL., 23:45–54, 2017. © 2015 Society of Plastics Engineers     

Recycling of blends of acrylonitrile–butadiene–styrene (ABS) and polyamide

The aim of this work is to evaluate routes to upgrade recycled engineering plastics, especially mixed plastics with acrylonitrile–butadiene–styrene copolymers (ABS) as the major component. A core‐shell impact modifier was successfully used to improve the impact strength of blends of ABS and ABS/polycarbonate (PC) blends recycled from the automotive industry. However, the presence of other immiscible components like polyamide (PA), even in small amounts, can lead to a deterioration in the overall properties of the blends. A styrene–maleic anhydride (SMA) copolymer and other commercial polymer blends were used to promote the compatibilization of ABS and PA. The core‐shell impact modifier was again found to be an efficient additive with regard to the impact strength of the compatibilized ABS/PA blends. The results obtained with fresh material blends were quite promising. However, in blends of recycled ABS and glass‐fiber‐reinforced PA, the impact strength did not exhibit the desired behavior. The presence of poorly bonded glass fibers in the blend matrix was the probable reason for the poor impact strength compared with that of a blend of recycled ABS and mineral‐filled PA. Although functionalized triblock rubbers (SEBS–MA) can substantially enhance the impact strength of PA, they did not improve the impact strength of ABS/PA blends because the miscibility with ABS is poor. The possibilities of using commercial polymer blends to compatibilize otherwise incompatible polymer mixtures were also explored giving promising results. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2535–2543, 2002     

In situ reactive compatibilized noryl/LCP blends

This article reveals that the already known improved properties of the thermoplastic–liquid crystalline polymer (LCP) blends can be further improved substantially over the corresponding noncompatibilized counterparts by using a reactive in situ type compatibilizer, the styrene–glycidyl methacrylate (SG) copolymer. This SG copolymer has been demonstrated in this article to be an effective reactive compatibilizer to improve the processability, heat deflection temperature, and mechanical properties of Noryl/LCP blends. The epoxy functional groups of the SG copolymer can react with the end groups of PPO (in Noryl) and LCP. The in situ-formed SG–g–LCP copolymer tends to reside along the interface of Noryl–LCP and reduces the interfacial tension during melt processing. The resultant LCP fibers in the Noryl matrix of the compatibilized blends have a higher aspect ratio because the fibers become finer, longer, and tend to form lamellate domains with a greater interphase contact area than those from the noncompatibilized blends. The compatibilized blends also improve the interphase adhesion between Noryl and LCP. The presence of ethyl triphenylphosphonium bromide catalyst promotes the grafting reaction to improve blend compatibilization. © 1995 John Wiley & Sons, Inc.     

The nature and location of SEBS–MA compatibilizer in polyethylene–wood flour composites

A maleic-anhydride-grafted styrene–ethylene—butylene–styrene (SEBS–MA) triblock copolymer has been used as a compatibilizer in low-density polyethylene–wood flour (LDPE–WF) composite system. The location of compatibilizer was studied using transmission electron microscopy (TEM). The unsaturated parts of the copolymer were stained with osmium tetraoxide (OsO₄) to enhance contrast between the different phases. TEM micrographs indicated that part of the compatibilizer was located at the interface between the wood particles and PE matrix and that wood was also stained by the OsO₄. The nature of the interface between the wood surface and the SEBS–MA was studied using Fourier transform infrared spectroscopy (FTIR). The results indicated that MA reacts with wood through esterification and hydrogen bonding and also possibly through interaction between the styrene and wood. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 201–209, 1998     

Compatibilization and elastomer toughening of polyamide‐6 (PA6)/poly(phenylene ether) (PPE) blends

In the elastomer‐modified (polyamide‐6/poly(phenylene ether) (PA6/PPE) = 50/50 blends, poly(styrene‐co‐maleic anhydride) (SMA) was demonstrated to be an efficient reactive compatibilizer. The G1651 elastomer was shown to be an effective impact modifier to result in superior toughness and heat‐deflection temperature (HDT) than is the 1901X elastomer for the SMA‐compatibilized blends because G1651 particles exclusively reside within the dispersed PPE phase but 1901X particles tend to distribute in the PA6 matrix and/or along the interface. The apparent average diameter of the dispersed PPE phase is insignificantly dependent on the elastomer content in the G1651‐modified blend, whereas it increases with increase of the elastomer content in the 1901X‐modified blend. Moreover, there exists a critical elastomer content, 15 phr, for the ductile–brittle transition of the G1651‐modified SMA‐modified PA6/PPE blends. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 23–32, 1999     

Preparation and characterizations of direct methanol fuel cell membrane from sulfonated polystyrene/poly(vinylidene fluoride) blend compatibilized with poly(styrene)‐b‐poly(methyl methacrytlate) block copolymer

This work concerned a development of sulfonated polystyrene (SPS)/poly(vinylidene fluoride) (PVDF) blend membrane for use as an electrolyte in a direct methanol fuel cell. The aim of this work was to investigate effects of the blend ratio on properties of the blend membranes. The partially SPS with various degrees of substitution were prepared by using propionyl sulfate as a sulfonating agent. After that, the optimum SPS was selected for further blending with PVDF, at various blend ratios. Poly(styrene)–poly(methyl methacrytlate) block copolymer (PS‐b‐PMMA), used as a compatibilizer, was synthesized via a controlled radical polymerization through the use of an iniferter. Thermal behaviors, water uptake, proton conductivity, and methanol permeability of various blend membranes were determine by using TGA, gravimetry, impedance analyzer, and gas chromatography, respectively. From the results, it was found that, water uptake and methanol permeability of the blend membranes tended to increase with the weight ratio of SPS. It was also found that the blend membranes were incompatible, especially those containing more than 40 wt % of the SPS. However, by adding 5 wt % of the block copolymer, the blend became more compatible. Mechanical strength, proton conductivity, and resistance to methanol crossover of the blend membrane remarkably increased after the compatibilization. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

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

Polypropylene 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     

Effects of reactive reinforced interface on the morphology and tensile properties of amorphous polyamide–SAN blends

The effects of reactive reinforced interface on the morphology and tensile properties of amorphous polyamide (a-PA) and styrene-acrylonitrile (SAN) copolymer blend have been investigated using styrene maleic anhydride (SMA) copolymer as a reactive compatibilizer. The anhydride groups of SMA copolymer can react with the amine groups of polyamide and form in situ graft copolymers at the a-PA–SAN interfaces during the blend preparation. The interfacial adhesion strength of the reactive reinforced interface was evaluated quantitatively using an asymmetric double cantilever beam fracture test as a function of SMA copolymer content using a model adhesive joint. The interfacial adhesion strength was found to increase with the content of SMA copolymer and then level off. The morphological observations of a-PA–SAN (80/20 w/w) blends showed that the finer dispersion of the SAN domains with rather narrow distribution was obtained by the addition of SMA copolymer into the blends. The trend of morphology change was not in accord with that of the interfacial adhesion strength with respect to the content of SMA copolymer. However, the results of tensile properties showed very similar behavior to the case of the interfacial adhesion strength with respect to SMA content; that is, there was an optimum level of the reactive compatibilizer beyond which the interfacial adhesion strength and tensile strength did not change significantly. These results clearly reveal that tensile properties of polymer blend are highly dependent on the interfacial adhesion strength. Furthermore, it is suggested that the asymmetric double cantilever beam fracture test using a model interface is a useful method to quantify the adhesion strength between the phases in real polymer blends. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1925–1933, 1998