Morphology and flame‐retardancy properties of ternary high‐impact polystyrene/elastomer/polystyrene‐encapsulated magnesium hydroxide composites

The effects of elastomer type on the morphology, flammability, and mechanical properties of high‐impact polystyrene (HIPS)/polystyrene (PS)‐encapsulated magnesium hydroxide (MH) were investigated. The ternary composites were characterized by cone calorimetry, mechanical testing, and scanning electron microscopy. Morphology was controlled with poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] (SEBS) triblock copolymer or the corresponding maleinated poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] (SEBS‐g‐MA). The HIPS/SEBS/PS‐encapsulated MH composites exhibited separation of the filler and elastomer, whereas the HIPS/SEBS‐g‐MA/PS‐encapsulated MH composites exhibited encapsulation of the filler by SEBS‐g‐MA. The flame‐retardant and mechanical properties of the ternary composites were strongly dependent on microstructure. The composites with an encapsulation structure showed higher flame‐retardant properties than those with a separation structure at the optimum use level of SEBS‐g‐MA. Furthermore, the composites with a separation structure showed a higher modulus and impact strength than those with an encapsulation structure. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Synergistic effects of zinc oxide in montmorillonite flame‐retardant polystyrene nanocomposites

In this study, two‐dimensional organic montmorillonite (OMMT) and one‐dimensional needlelike ZnO were used as flame retardants of polystyrene (PS). Polystyrene/organic montmorillonite (PMT) and polystyrene/organic montmorillonite/zinc oxide nanocomposites (PMZs) with different weight ratios were prepared by melt intercalation. Information on the morphologies and structures of the PS nanocomposites was obtained with Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results indicate that a mixed exfoliated–intercalated structure was observed in the PMT and PMZs. Dynamic mechanical thermal analysis showed that both the storage modulus and glass‐transition temperature values of the PMT and PMZs were significantly improved compared with those of the neat PS. The mechanical property tests showed that the bending modulus values of both PM5 (PS/OMMT weight ratio = 95:5) and PMZs increased compared with that of pristine PS. PMZ1 (PS/OMMT/ZnO weight ratio = 94:5:1) provided no decrease in the tensile strength in comparison with PS. A synergistic effect was observed between OMMT and ZnO; this resulted in improvements in the flame retardancy and dynamic mechanical properties in the PMZs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43047.     

The influence of filler surface modification on mechanical and material properties of layered double hydroxide‐containing polypropylene composites

The processing and properties of layered double hydroxides (LDHs)‐containing polypropylene (PP) composites have been studied extensively. However, no detailed studies have reported on how stearic acid (SA)‐intercalated and SA‐coated LDHs influence the properties of melt‐processed PP/LDH composites. Here, four different types of LDHs: synthesized (cLDH1) and commercial (cLDH2) SA‐coated LDH, SA‐intercalated LDH (iLDH), and unmodified LDH (nLDH), were used to fabricate composites using a master‐batch‐dilution technique in a twin‐screw extruder. The characterization results showed that microcomposites were formed when cLDH2 and nLDH were used, whereas nanocomposites were formed when iLDH and cLDH1 were used. Strong nucleating behavior was observed for the nLDH‐, cLDH1‐, and cLDH2‐containing composites, whereas iLDH delayed the crystallization process of the PP matrix. A significant improvement in modulus, with a balance of tensile and impact strengths, was observed in the case of the cLDH1‐containing composite, whereas the nLDH‐containing composite showed good improvement in temperature‐dependent load‐bearing capacity. On the other hand, the PP/iLDH composite showed a remarkable improvement in thermal stability and a reduction in the peak‐heat‐release rate. Therefore, this study gives us an opportunity to design PP composites with desired properties by the judicious choice of LDH, which further widens the application of PP matrices. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45024.     

Preparation and properties of nadic‐end‐capped cyclotriphosphazene‐containing polyimide/carbon fiber composites

New novel fire‐resistant and heat‐resistant cyclotriphosphazene‐containing polyimide resins were prepared in situ by the polymerization of (p‐aminophenoxy)(phenoxy)cyclotriphosphazenes with 3,3′,4,4′‐benzophenonetetracarboxylic acid or 3,3′,4,4′‐diphenylsulfonetetracarboxylic acid and a crosslink agent, 5‐norbornene‐2,3‐dicarboxylic acid and were used as polymer matrix compositing with a woven carbon fiber to prepare nadic‐end‐capped cyclotriphosphazene‐containing polyimide/carbon fiber composites. The thermal stability, flame retardance, morphology of the surface fracture, and some physical properties of the composites were investigated by thermogravimetric analysis, scanning electron microscopy, and a material testing system, respectively. The composites had good thermal stability, flame retardance, and mechanical properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 810–818, 2003     

Influence of aging conditions on the mechanical properties and flame retardancy of HIPS composites

In this study, we evaluate the changes in physical properties and flame retardancy of HIPS composites after natural aging tests in Turpan (high sunlight radiation dose and dry) and Qionghai (high temperature and rainy) in China for 21 months. The HIPS composite aged in Turpan revealed a higher chromatic aberration than that in Qionghai due to the higher sunlight radiation dose. After aging tests for 21 months, the mechanical properties and the peak heat release of the HIPS composite aged in Qionghai decreased by more than 50% and increased by 39.7%, respectively, results that were worse than for the HIPS composite in aged Turpan. This was related to the combined effects of light, temperature, rain, and moisture in Qionghai leading to more severe degradation of HIPS composites, which results in breaking of the polymer chains and migration and erosion of the flame retardant. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46339.     

Flame‐retardant mechanism of expandable polystyrene foam with a macromolecular nitrogen–phosphorus intumescent flame retardant

Expandable polystyrene (EPS) foam is largely used as the thermally insulating external wall in buildings and constructions, but it is extremely flammable because of the presence of almost 98% air into its porous structure, its high surface‐area‐to‐mass ratio, and its elemental composition. Lots of serious fire disasters caused by EPS foam have posed great threats to people's properties and lives in recent years. Thus, a halogen‐free, flame‐retardant EPS is urgently needed, and its preparation is still a global challenge. To solve the problem that it is easy for EPS foam to form melt dripping and difficult for it to generate a char layer during the combustion process, a macromolecular nitrogen–phosphorus intumescent flame retardant (MNP) was selected to prepare flame‐retardant EPS foam and good mechanical and flame‐retardant properties were obtained. The scanning electron microscopy characterization revealed that MNP could penetrate into the gap between the beads, and a thin physical coating layer formed on the surface of the bead. The data from the thermogravimetry–Fourier transform infrared test indicated that a nitrogenous noncombustible gas was generated by the pyrolysis of MNP. When the MNP content increased to 30%, the limiting oxygen index and the smoking density rate of the EPS–MNP foam were 28.8 and 23.6, respectively, and a UL94 V‐0 classification was achieved. In addition, the heat‐release rate, total heat‐release, smoke produce rate, and carbon dioxide production of the EPS–MNP foams all decreased obviously; this was attributed to the flame‐retardant effects of MNP in both the condensed and gas phases. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44356.     

Interfacial modification of high impact polystyrene magnesium hydroxide composites effects on flame retardancy properties

High impact polystyrene (HIPS)/magnesium hydroxide (MH) composites were prepared by melt‐blending. Two kinds of interfacial modifiers were used in this research, maleinated poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] (SEBS‐g‐MA) triblock copolymer and PS. The effects of the use levels of SEBS‐g‐MA on the flame retardancy of HIPS/elastomer/MH based on unmodified and PS‐modified surface were investigated by TEM, FTIR, and combustion tests (horizontal burning test and cone calorimetry). The combustion results showed that comparing composites containing unmodified MH, the flame retarding properties of composites containing PS‐modified MH were obviously improved. The increased performance can be explained that the PS covered on the surface of MH could further improve dispersion of the filler in matrix. Furthermore, there existed a critical thickness of interfacial boundary for optimum flame‐retarding properties in both ternary composites based MH and PS‐modified MH. When the interfacial boundary relative thickness is less than 0.53, the introduction of SEBS‐g‐MA can improve the dispersion degree, leading the improvement of flame retardancy properties. However, with the increase of interfacial boundary thickness, the SEBS‐g‐MA coating around MH acted as a heat and mass transfer barrier, leading to the reduction of flame retardancy. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Wood–high‐density polyethylene composites: Water absorption and mechanical properties

In this research, the effect of water absorption on the mechanical properties of wood/high‐density polyethylene (HDPE) composites were investigated. HDPE (44005ARPC) was used as the polymer matrix, and spruce sawdust was used as the filler at a maximum loading of 50 wt % of the total weight of each compound. All compounds contained 5 wt % magnesium stearate as a lubricant and 0.5 wt % Irgafos 168 as a heat stabilizer. Four factors in two levels were chosen [talc (filler) at levels of 5 and 15 wt %, zinc borate (fungicide) at levels of 0 and 1 wt %, maleic anhydride polyethylene (coupling agent) at levels of 4 and 6 wt %, and method of mixing (one‐step vs. two‐step mixing)], and eight compounds were prepared with an L8 Taguchi orthogonal array which has 8 combinations of levels. The effects of each factor at two levels on the diffusion constant and the tensile and bending strengths (under wet and dry conditions) were investigated by the analysis of variance of means with 90% confidence. The optimum level for each factor is reported. The results show that there was a linear correlation between the diffusion constant and tensile and bending strengths when the samples were immersed in distilled water. A higher diffusion constant resulted in much lower tensile and bending strengths with immersion in distilled water until saturation was reached. Scanning electron microscopy images confirmed good mixing when two‐steps mixing was used. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Influence of fumed silica on the flame‐retardant properties of ethylene vinyl acetate/aluminum hydroxide composites

The flammability and synergistic flame‐retardant effects of fumed silica (SiO₂) in ethylene vinyl acetate (EVA)/aluminum hydroxide (ATH) blends were studied with limiting oxygen index measurements, UL 94 testing, cone calorimeter testing (CONE), and thermogravimetric analysis (TGA). The results show that the addition of a given amount of fumed SiO₂ can apparently improve UL 94 rating. The CONE data indicated that the addition of fumed SiO₂ greatly reduced the heat release rate. The TGA data showed that this synergistic flame‐retardant mechanism of fumed SiO₂ in the EVA/ATH materials was mainly due to the physical process. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Morphology and mechanical properties of high‐impact polystyrene/elastomer/magnesium hydroxide composites

Ternary composites of high‐impact polystyrene (HIPS), elastomer, and magnesium hydroxide filler encapsulated by polystyrene were prepared to study the relationships between their structure and mechanical properties. Two kinds of morphology were formed. Separation of elastomer and filler was found when a nonpolar poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] triblock copolymer (SEBS) was incorporated. Encapsulation of filler by elastomer was achieved by using the corresponding maleinated SEBS (SEBS‐g‐MA). The mechanical properties of ternary composites were strongly dependent on microstructure. In this study, the composites with separate dispersion structure showed higher elongation, modulus and impact strength than those of encapsulation structure. Impact‐fracture surface observation showed that the toughening mechanism was mainly due to the massive cavitation and extensive matrix yielding. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5184–5190, 2006     

Epoxy resin/phosphorus‐based microcapsules: Their synergistic effect on flame retardation properties of high‐density polyethylene/graphene nanoplatelets composites

Two types of microcapsule flame retardants are prepared by coating ammonium polyphosphate (APP) and aluminum diethylphosphinate (ADP) with epoxy resin (EP) as the shell via in situ polymerization, and blended with high density polyethylene (HDPE)/graphene nanoplatelets (GNPs) composites to obtain flame‐retardant HDPE materials. Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), and water contact angle results confirm the formation of core–shell structures of EP@APP and EP@ADP. The limiting oxygen index (LOI), vertical burning test (UL‐94), cone calorimetry, and Raman spectroscopy are employed to characterize the HDPE/GNPs composites filled with EP@APP and EP@ADP core–shell materials. A UL94 V‐0 level and LOI of 34% is achieved, and the two flame retardants incorporated in the HDPE/GNPs composite at 20 wt % in total play a synergistic effect in the flame retardancy of the composite at a mass ratio of EP@ADP:EP@APP = 2:1. According to the cone‐calorimetric data, the compounding composites present much lower peak heat release rate (300 kW/m²) and total heat release (99.4 MJ/m²) than those of pure HDPE. Raman spectroscopic analysis of the composites after combustion reveals that the degree of graphitization of the residual char can reach 2.31, indicating the remarkable flame retarding property of the composites. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46662.     

Char barrier effect of graphene nanoplatelets on the flame retardancy and thermal stability of high‐density polyethylene flame‐retarded by brominated polystyrene

Graphene nanoplatelets (GNPs) with the char barrier effect were combined with brominated polystyrene (BPS) and antimony trioxide (Sb₂O₃) to improve the flame retardancy and thermal stability of high‐density polyethylene. Thermogravimetric analysis, limited oxygen index (LOI) testing, and vertical burning testing (UL‐94) showed that the presence of GNPs led to enhanced thermal oxidation stability and significantly reduced the flammability. The addition of 1 wt % GNPs to polyethylene/BPS–Sb (mass ratio = 92/6/2) led to UL‐94 grades from NG (first burning time > 30 s) to V‐2 (total burning time = 14 s), and the LOI value increased from 23.4 to 24.1%. The results of the pyrolysis products provided evidence that the GNPs restricted volatilization. The morphology of the chars also proved the formation of the char layer, which could act as a barrier to isolate the material from the flame and retard the vaporization of flammable gases via a tortuous pathway. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40520.     

Structural and mechanical properties of YBCO‐polystyrene composites

Microcrystalline powders of yttrium barium copper oxide [YBa₂Cu₃O₇] have been prepared by conventional ceramic preparation technique. The powder belong to orthorhombic symmetry with unit cell dimensions ‘a’=3.8214 Å, ‘b’=3.8877 Å and ‘c’=11.693 Å. XRD and SEM studies revealed that its particle size is in the micrometer range. Micro composites of polystyrene with different loading of yttrium barium copper oxide fillers were prepared by melt mixing in a brabender plasticorder at a rotor speed of 60 rpm. The lattice parameters of the constituent phases are the same in all the composites. Mechanical properties such as stress–strain behavior, Young's modulus, and tensile strength were studied as a function of filler loading. Addition of filler enhances the Young's modulus of the polymer. Because of the poor filler‐matrix adhesion, tensile strength and strain at break decreases with filler loading. To explore more carefully the degree of interfacial adhesion between the two phases, the results were analyzed by using models featuring an adhesion parameter. Finally experimental results were compared with theoretical predictions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Copolymerization of 1‐oxo‐2,6,7‐trioxa‐1‐phorsphabicyclo[2,2,2]oct‐4‐yl methyl acrylate and (10‐oxo‐10‐hydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐yl) methyl acrylate with styrene and their thermal degradation characteristics

Two phosphorus‐containing acrylates of 1‐oxo‐2,6,7‐trioxa‐1‐phorsphabicyclo[2,2,2]oct‐4‐yl methyl acrylate and (10‐oxo‐10‐hydro‐9‐oxa‐10λ⁵‐phosphaphenanthrene‐10‐yl) methyl acrylate were free‐radical‐copolymerized with styrene (St). The r₁ reactivity ratio values (related to the novel acrylates) were 0.342 and 0.225, respectively, and the r₂ reactivity ratio values (related to St) were 0.432 and 0.503, respectively. The thermal stability of the copolymers was tested by thermogravimetric analysis (TGA) in N₂ or air, and the ignitability was tested by measurements of UL‐94 vertical combustion tests and the limiting oxygen index. The results of TGA and combustion tests indicated that the effect of flame retardancy was determined by the nature of the phosphorus‐containing substituent. Compared with the 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide based group, the 1‐oxo‐2,6,7‐trioxa‐1‐phorsphabicyclo[2,2,2]oct‐4‐yl methol based group could enhance the ability of char formation with an antidripping effect. It is concluded that phosphorus‐containing acrylates are potential flame‐retarding monomers for styrenic polymers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Flame‐retardant properties of acrylonitrile–butadiene–styrene/wood flour composites filled with expandable graphite and ammonium polyphosphate

Expandable graphite (EG) and ammonium polyphosphate (APP) were used to improve the flame retardancy of acrylonitrile–butadiene–styrene based wood–plastic composites (WPCs). A synergistic effect between EG and APP on the flame retardancy of the WPCs was proposed. The results show that the highest limited oxygen index (LOI) of 34.2% and a V‐0 rating were achieved when the ratio of EG to APP 12.5:7.5; this comprised 20 wt % of the total amount. However, LOI values of the samples with EG and APP alone were only 30.5 and 24.5%, respectively. Thermogravimetric analysis indicated that the flame retardants improved the amount of residue. The EG and EG/APP additives greatly decreased the peak heat release rate and suppressed smoke according to cone calorimetry testing. The scanning electron microscopy analysis indicated that the surface of the wormlike char was covered with a granular substance, which may have been the viscous phosphoric acid or poly(phosphoric acid) decomposed from APP. The flame‐retardant additives worsened the mechanical properties of the WPCs. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40281.     

Effect of expandable graphite particle size on the flame retardant,mechanical, and thermal properties of water‐blown semi‐rigid polyurethane foam

Different particle size of expandable graphite (EG) were incorporated into water‐blown semi‐rigid polyurethane foams (SPFs), which acted as the fire shield, in order to enhance the fire retardant properties. In this study, the particle size of EG was systematically varied from 70 µm to 960 µm. The effect of EG particle size on the density, mechanical properties, and thermal stability of SPFs was also investigated. Results showed that EG with smaller particle size showed almost no effect on the fire retardant properties of SPFs while the larger particle size of EG could effectively enhance it. It was observed that the flame retardancy of the composite improved with the increase of EG size which was attribute to the formation and densification of isolation layer with the increase in volume of expanded graphite. Limiting oxygen index (LOI) value of EG/SPF composites increased linearly by two steps with the increase in EG particle size. Horizontal burning test confirmed the above conclusion. Thermogravimetric analysis (TGA) indicated that EG particles and its size exhibited minor effect on the thermal stability of the SPF composites. Moreover, SPF filled with medium particle size of EG (about 400 µm) exhibited a poor compression performance compared with the others. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39885.     

Flame retardancy and water resistance of novel intumescent flame‐retardant oil‐filled styrene–ethylene–butadiene–styrene block copolymer/polypropylene composites

A novel halogen‐free flame‐retardant composite consisting of an intumescent flame retardant (IFR), oil‐filled styrene–ethylene–butadiene–styrene block copolymer (O‐SEBS), and polypropylene (PP) was studied. On the basis of UL‐94 ratings and limiting oxygen index (LOI) data, the IFRs consisted of a charring–foaming agent, ammonium polyphosphate, and SiO₂ showed very effective flame retardancy and good water resistance in the IFR O‐SEBS/PP composite. When the loading of IFR was only 28 wt %, the IFR–O‐SEBS/PP composite could still attain a UL‐94 V‐0 (1.6 mm) rating, and its LOI value remained at 29.8% after a water treatment at 70°C for 168 h. Thermogravimetric analysis data indicated that the IFR effectively enhanced the temperature of the main thermal degradation peak of the IFR–O‐SEBS/PP composites because of the formation of abundant char residue. The flammability parameters of the composites obtained from cone calorimetry testing demonstrated that water treatment almost did not affect the flammability behavior of the composite. The morphological structures of the char residue and fractured surfaces of the composites were not affected by the water treatment. This was attributed to a small quantity of IFR extracted from the composite. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39575.     

Dynamic mechanical behavior of atactic and high‐impact polystyrene

Results of the dynamic mechanical behavior of atactic polystyrene (PS) and high‐impact polystyrene (HIPS) for temperatures between 300 and 425 K at a frequency of the order of 50 kHz are presented. The storage Young's modulus, (E′), of the HIPS is lower than the PS value, being the relationship between them a function of the rubber phase volume fraction, independent of the measurement frequency. The glass transition temperature (T_g) of HIPS is shifted to lower temperature in respect to the PS. The γ relaxation appears at 308 K in PS at 50 kHz, while it seems to move toward lower temperatures in the HIPS. Both shifts are attributed to the presence of mineral oils in the HIPS. The values of E′, T_g, and the temperature of the γ relaxation at 50 kHz are discussed within the scope of the theory of viscoelasticity. Finally, the effect of thermal treatments, using different annealing times, on the behavior of both materials is shown. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 865–873, 2000     

A DOPO-base Schiff derivative used as a flame retardant for polystyrene

A novel 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-based Schiff base derivative, 6,6′-(1,4-phenylenebis (((3-hydroxyphenyl)amino) methylene)) bis (dibenzo [c,e] [1,2] oxaphosphinine 6-oxide) (SD), was synthesized and applied to polystyrene. The structure of terephthalaldehyde dihydroxymethane benzene and SD are characterized by Fourier-transform infrared (FTIR) spectroscopy, ¹H-nuclear magnetic resonance spectroscopy, and elemental analysis. The results of thermogravimetric analysis tests show that the residue of the SD/PS composites increased from 0.21 to 7.09% with the increase of SD content, indicated that the thermal stability of the SD/PS composites was significantly improved. The introduction of SD also efficiently ameliorated the flame-retardant property of SD/PS composites with limiting oxygen index increased by 33.15%, rated UL-94 vertical burning test V-0 rating, lower peak heat release rate, and total heat release. The mechanism of SD/PS composite was explored by scanning electron microscopy images and FTIR spectra of residue of SD/PS composites after calcination by muffle furnace. These tests prove that SD can be used as an effective polystyrene (PS) flame retardant.     

Flammability and mechanical properties of wood flour‐filled polypropylene composites

Polypropylene (PP) composites filled with wood flour (WF) were prepared with a twin‐screw extruder and an injection‐molding machine. Three types of ecologically friendly flame retardants (FRs) based on ammonium polyphosphate were used to improve the FR properties of the composites. The flame retardancy of the PP/WF composites was characterized with thermogravimetric analysis (TGA), vertical burn testing (UL94‐V), and limiting oxygen index (LOI) measurements. The TGA data showed that all three types of FRs could enhance the thermal stability of the PP/WF/FR systems at high temperatures and effectively increase the char residue formation. The FRs could effectively reduce the flammability of the PP/WF/FR composites by achieving V‐0 UL94‐V classification. The increased LOI also showed that the flammability of the PP/WF/FR composites was reduced with the addition of FRs. The mechanical property study revealed that, with the incorporation of FRs, the tensile strength and flexural strength were decreased, but the tensile and flexural moduli were increased in all cases. The presence of maleic anhydride grafted polypropylene (MAPP) resulted in an improvement of the filler–matrix bonding between the WF/intumescent FR and PP, and this consequently enhanced the overall mechanical properties of the composites. Morphological studies carried out with scanning electron microscopy revealed clear evidence that the adhesion at the interfacial region was enhanced with the addition of MAPP to the PP/WF/FR composites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010