Viscoelastic properties of borax loaded CMC‐g‐cl‐poly(AAm) hydrogel composites and their boron nutrient release behavior

Borax (Na₂B₄O₇, 10.5% Boron) loaded CMC‐g‐cl‐poly(AAm) hydrogel composites were prepared by in situ grafting of acrylamide on to sodium carboxymethyl cellulose in the presence of borax by free radical polymerization technique to develop slow boron (B) delivery device. The composition, morphology, and mechanical properties of synthesized composites were studied by X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, texture analyser, and dynamic shear rheometer. Characterization revealed formation of borate ion ( ) from borax during polymerization reaction leading to extensive crosslinking of cellulosic chains and generation of mechanically strong composite hydrogels. Dynamic release of from the synthesized composites hydrogels followed Fickian diffusion mechanism and composites with high mechanical strength resulted in slow release of B. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43969.     

Reactive compatibilization of poly(methyl acrylate‐ran‐acrylonitrile)/poly(ethylene) blends through amine–anhydride coupling

Methyl acrylate/acrylonitrile copolymers (MA/AN) were reactively compatibilized as the dispersed phase into poly(ethylene) (PE) for potential hydrocarbon barrier materials. The MA/AN was made reactive by including p‐aminostyrene (PAS), yielding terpolymers (MA/AN/PAS) with pendant primary amine functionality (number average molecular weight = 65–133 kg mol^?1, dispersity (?)=1.83–2.53, molar composition of PAS in copolymer F_PAS = 0.03–0.14, molar composition of AN = F_AN = 0.27–0.52). The non‐functional MA/AN and amino functional MA/AN/PAS were each melt blended into PE that was grafted with maleic anhydride (PE‐g‐MAnn) at 200 °C at 70:30 wt % PE‐g‐MAnn:co/terpolymer. After extrusion, the dispersed phase particle size (volume to surface area diameter, ) was coarse (12.6 μm) for the non‐reactive blend whereas it was much lower for the reactive blend ( = 1.2 μm). Coarsening after annealing at 150 °C was slow, but the domain sizes increased only slightly for both cases. The reactive blend was deemed sufficiently stable and thus was suitable as a candidate barrier material for further testing against olefins. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44177.     

Preparation and characterization of thermo‐sensitive poly(vinyl alcohol)‐based hydrogel as drug carrier

Poly(vinyl alcohol)s (PVA) with high and low molecular weights were chemically modified by introducing acetaldehyde onto the polymer backbone to induce thermal‐responsive properties. The influence of both molecular weight ( ) and acetalization degree on the lower critical solution temperature (LCST) of thermo‐sensitive polymer was investigated. Moreover, a temperature responsive hydrogel was prepared by controlled cross‐linking of acetalized poly(vinyl alcohol) (APVA) and glutaraldehyde. As a model drug, ciprofloxacin was introduced into the prepared thermal sensitive hydrogel to reveal the drug loading and release behaviors. The structure, thermo‐sensitivity, swelling/deswelling kinetics, morphology, and drug loading/release behaviors were also investigated. The results indicated that the APVA polymer solution exhibited temperature responsivity, and APVA with high acetalization degree showed low LCST, whereas those with high PVAs showed high LCST. Meanwhile, morphology study was identical with the swelling/de‐swelling behavior. The loading and release of ciprofloxacin were controllable. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39720.     

A novel porous nanocomposite of aminated silica MCM‐41 and nylon‐6: Isotherm,kinetic, and thermodynamic studies on adsorption of Cu(II) and Cd(II)

Porous amine‐modified MCM‐41/Nylon‐6 nanocomposite (NH₂‐MCM‐41/NY6 NC) was synthesized by a facile solution casting protocol, which was used as an effective adsorbent for the removal of Cu(II) and Cd(II) from aqueous media. The physicochemical properties of NH₂‐MCM‐41/NY6 NC were studied by scanning and transmission electron microscopies, thermogravimetric analysis, etc. The influence of pH, adsorbent dose, contact time and initial concentration on adsorption performance were investigated in detail. Kinetic and isotherm parameters were evaluated and the data fitted well to the pseudo‐second order and Freundlich isotherm model, respectively. The maximum adsorption capacities of Cu(II) and Cd(II) were about 35.84 and 27.5 mg·g^?1, respectively. The K_d of NH₂‐MCM‐41/NY6 NC for Cu(II) (> ) and Cd(II) (> ) ions uptake in aqueous solution, showed very good values. Thermodynamic parameters suggest that the adsorption is a spontaneous process with an endothermic nature. According to the results obtained, we conclude that this novel porous NH₂‐MCM‐41/NY6 NC could be used for the removal of heavy metal ions from an aqueous solution. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45383.     

Reactive compatibilization of poly(styrene‐ran‐acrylonitrile)/poly(ethylene) blends through the acid–epoxy reaction

Two families of acid functional styrene/acrylonitrile copolymers (SAN) for application as dispersed phase barrier materials in poly(ethylene) (PE) were studied. One type is SAN made by nitroxide mediated polymerization (NMP), which was subsequently chain extended with a styrene/tert‐butyl acrylate (S/tBA) mixture to provide a block copolymer (number average molecular weight M_n = 36.6 kg mol^?1 and dispersity ? = 1.34, after which the tert‐butyl protecting groups were converted to acid groups (SAN‐b‐S/AA). The other acid functional SAN is made by conventional radical terpolymerization (SAN‐AA). SAN‐AA and SAN‐b‐S/AA were each melt blended with PE grafted with epoxy functional glycidyl methacrylate (PE‐GMA) at 160 °C in a twin screw extruder (70:30 wt % PE‐GMA:SAN co/terpolymer). The non‐reactive PE‐g‐GMA/SAN blend had a volume to surface area diameter = 3.0 μm while the reactive blends (via epoxy/acid coupling) (PE‐GMA/SAN‐b‐SAA and PE‐GMA/SAN‐AA) had = 1.7 μm and 1.1 μm, respectively. After thermal annealing, the non‐reactive blend coarsened dramatically while the reactive blends showed little signs of coarsening, suggesting that the acid/epoxy coupling was effective for morphological stability. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44178.     

Structure and Photoluminescence of A Blue‐Green‐Emitting Phosphor for Near‐UV White LEDs

A series of phosphors Ca_12(0.97?x)Al₁₄O₃₂F₂: 0.03Ce³⁺, xTb³⁺ have been prepared by a hightemperature solid‐state reaction using boric acid as flux. These oxyfluorides crystallize in cubic structure, space group. Under the near ultraviolet excitation within wavelength range 310–390 nm, Ca_12(0.97?x)Al₁₄O₃₂F₂: 0.03Ce³⁺, xTb³⁺ phosphors exhibit an intense emission covering a broad band of 370–500 nm derived from the 5d→4f transitions of Ce³⁺ and a characteristic emission at 544 nm of Tb³⁺. The emission can be tuned from blue to green by altering the relative ratio of Ce³⁺ to Tb³⁺ in the composition. The energy‐transfer mechanism from Ce³⁺ to Tb³⁺ is investigated based on the site occupancy of the luminescence center in the crystal structure of the Ca₁₂Al₁₄O₃₂F₂ host. More importantly, when a certain amount of boric acid is added as flux in the synthesis, the fluorescence intensity of the phosphors increases about 65%. Because of its broad excitation and efficiently tunable blue to green luminescence, the Ca_12(0.97?x)Al₁₄O₃₂F₂: 0.03Ce³⁺, xTb³⁺ phosphors may find promising application as a near UV‐convertible phosphor for white‐light‐emitting diodes.     

Cross‐linked chitosan beads for phosphate removal from aqueous solution

Chitosan beads were cross‐linked with glutaraldehyde (GA) and epichlorohydrin (EP), respectively, at variable composition. The general features of the adsorptive and textural properties of the bead systems were characterized using p‐nitrophenolate (PNP) at pH 8.5. As well, a systematic adsorption study of phosphate dianion (phosphate ( ) species was carried out in aqueous solution at pH 8.5 and 295 K. The Sips isotherm model yielded adsorption parameters for the chitosan bead systems: (i) monolayer adsorption capacity (Q_m) for PNP ranged from 0.30 to 0.52 mmol g^?1 and (ii) Q_m values for the bead systems with ranged from 22.4–52.1 mg g^?1 for these conditions. GA cross‐linked beads reveal greater Q_m values for PNP while EP cross‐linked beads showed greater Q_m values for , in accordance with the surface chemistry and the materials design described herein. The EP cross‐linked beads show favorable adsorption–desorption properties and represents a promising tunable adsorbent system for the effective removal of phosphate dianion species in aqueous solution. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42949.     

Synthesis of a novolac‐based 3‐aminopropylsiloxane resin and its application for the removal of Cu2+, Cr3+, and Ni2+ from electroplating wastewater

Novolac resin was modified with 3‐aminopropyltrimthoxysilane to obtain phenol‐formaldehyde‐aminopropylsiloxane resin (PF‐APS). Fourier transformation infra‐red spectra, thermogravimetric analysis, elemental analysis, and pH‐metric titration were used to characterize PF‐APS. Its chemical formula was suggested to be C₁₄H_12.49N_0.1O₂Si_0.1. The resin shows high experimental metal ions uptake capacity within short time of equilibration. The metal capacity was determined by atomic absorption spectrometry to be 0.787 mEq Cu/g. Maximum separation efficiencies of Cu²⁺, Cr³⁺, and Ni²⁺ from aqueous solutions on PF‐APS were at pH 8.0 and time of stirring 60 min; 94.0%, 90.8%, 83.2%, respectively. No significant interference from the background ions Na⁺, Cl^?, and was observed on the separation process. The heavy metal ions were eluted using 0.01 mol L^?1 EDTA at 65°C releasing >94% of the separated metal ions. The method of separation was applied successfully to remove the heavy metal ions Cu²⁺, Cr³⁺, and Ni²⁺ from electroplating wastewater from Dekirnis, Dakahlia Governorate, Egypt. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40993.     

A highly selective polybenzimidazole‐4,4′‐(hexafluoroisopropylidene)bis(benzoic acid) membrane for high‐temperature hydrogen separation

A polymeric gas separation membrane utilizing polybenzimidazole based on 4,4′‐(hexafluoroisopropylidene)bis(benzoic acid) was prepared. The synthesized membrane has an effective permeating area of 8.3 cm² and a thickness of 30 ± 2 µm. Gas permeation properties of the membrane were determined using H₂, CO₂, CO, and N₂ at temperatures ranging from 24°C to 200°C. The PBI‐HFA membranes not only exhibited excellent H₂ permeability, but it also displayed superior gas separation performance particularly for H₂/N₂ and H₂/CO₂. The permeation parameters for both permeability and selectivity [ and α(H₂/N₂); and α(H₂/CO₂)] obtained for the new material were found to be dependent on trans‐membrane pressure difference as well as temperature, and were found to surpass those reported by Robeson in 2008. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42371.     

Synthesis and characterization of PEDOT derivative with carboxyl group and its chemo sensing application as enhanced optical materials

Poly(4‐(((2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐2‐yl)methoxy)methyl)benzoic acid) (PEDOT‐Ph‐COOH) was facilely synthesized by the direct electropolymerization of 4‐(((2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐2‐yl)methoxy)methyl)benzoic acid (EDOT‐Ph‐COOH) in CH₂Cl₂‐Bu₄NPF₆ (0.10 M) system, and the PEDOT‐Ph‐COOH films were systematically investigated. The results displayed that the film had excellent reversible redox activities, good electrochemical performance, and rough and compact surface. Finally, the PEDOT‐Ph‐COOH film was used as an optical chemo‐sensor for the highly selective and sensitive detection of F^?, , , , Cu²⁺, and Fe³⁺ in dimethyl sulfoxide. Satisfactory results indicated that optical chemo‐sensor based on PEDOT‐Ph‐COOH possessed an excellent sensing performance and enhanced optical response, and it might be as potential promising materials, such as electrochromic devices, supercapacitors and so on. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41559.     

Effect of Ca2+ induced crosslinking on the mechanical and barrier properties of cast alginate films

The use of alginate as a coating material for packaging applications is currently limited due to its difficult processability and high moisture sensitivity. Therefore, this study addresses the crosslinking and scale‐up to a continuous application. Three different crosslinking agents were applied: CaCl₂ with ethylene diamine tetraacetic acid and two low soluble salts (CaHPO₄ and CaCO₃). Those were incorporated by internal setting in an alginate matrix with varying Ca²⁺ concentration ( ) and ratio. With the addition of Ca²⁺, the tensile strength and elongation at break of the cast alginate films increased. This was optimal for a of 0.010–0.015 g (g alginate)^?1 dependent on the crosslinking agent. The decrease in water vapor and oxygen permeability due to crosslinking was independent of the crosslinking agent. However, the optimal aiming to decrease permeability was different for the crosslinking agents: CaHPO₄ showed best results at a of 0.010 g (g alginate)^?1, CaCl₂ at 0.012 g (g alginate)^?1, and CaCO₃ at 0.027 g (g alginate)^?1. Upon all analyzed properties CaHPO₄ was the most promising crosslinking agent for alginate. Moreover, selected alginate formulations were successfully processed in a continuous lacquering plant. The produced two‐layer systems have very low oxygen permeabilities which can be further reduced by crosslinking. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45754.     

High‐performing dye‐sensitized solar cells based on reduced graphene oxide/PEDOT‐PSS counter electrodes with sulfuric acid post‐treatment

Four kinds of counter electrodes are prepared with polystyrene‐sulfonate doped poly(3,4‐ethylenedioxythiophene) (PEDOT‐PSS) as basic material, reduced graphene oxide (rGO) sheets as additives and H₂SO₄ as treating agent. The cyclic voltammetry and Tafel polarization are measured to evaluate catalytic activity of these counter electrodes for /I^? redox couple. It is found that H₂SO₄ treated rGO and PEDOT‐PSS hybrid counter electrode (S/rGO/PEDOT‐PSS counter electrode) has the highest catalytic activity among these counter electrodes. Power conversion efficiency of the dye‐sensitized solar cell with S/rGO/PEDOT‐PSS counter electrode can attain to 7.065%, distinctly higher than that of the cells with the other three ones, owing to the great enhanced fill factor and short‐circuit current density. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42648.     

Synthesis and properties of fluorescent light‐emitting polyamide hybrids with reactive nanosilica by epoxide functionalization

A series of poly(carbazole‐quinoxaline‐amide)s (PCQAs) containing phenyl and long alkyl chain as pendants was synthesized from polycondensation between a new diamine with a synthesized and several commercial dicarboxylic acids using Yamazaki's method. PCQAs had inherent viscosities and weight average molecular weights ( ) in the range of 0.48–0.62 dL g^?1 and 51,600–58,500 g mol^?1, respectively. These luminescent polymers are readily soluble in a variety of organic solvents and formed low‐colored and tough thin films. In this study, silane modified SiO₂ (mSiO₂) nanoparticles were prepared, characterized and used with PCQAs in preparation of nanocomposites via solution blending method. The interfacial interaction strength between mSiO₂ and the polymer–matrix enhanced thermal stability (T_10%, from 463°C to 500°C) and mechanical strength (from 100 MPa to 150 MPa) for composite containing 30 wt % mSiO₂ in comparison with the pure polyamide. These materials showed good ability for extraction–elimination of metal ions such as Cr⁶⁺, Cr³⁺, Co²⁺, Zn²⁺, Pb²⁺, Cd²⁺, and Hg²⁺ from aqueous solutions either individually or in the mixture at various pH. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40219.     

Removal of ammonium‐nitrogen from aqueous solution using chitosan‐coated bentonite: Mechanism and effect of operating parameters

Wastewater containing high concentration of ammonium‐nitrogen ( ) is not effectively addressed by biological treatment and when released into water bodies can cause eutrophication. In this study, the removal of from simulated wastewater using chitosan‐coated bentonite (CCB) was investigated. The effects of salt used, pH, CCB dosage, agitation rate, and temperature on the removal of were studied. The highest removal of 67.5% was attained at the following conditions: initial pH 4.0, CCB dose of 8.0 g, agitation rate of 150 rpm, and temperature of 35 °C. Fourier transform infrared analysis indicated two mechanisms: adsorption onto CCB involving hydrogen bonding with hydroxyl groups ( OH) and ion exchange between and cations present in the interlayer of bentonite. Experimental data follows the pseudo‐second‐order kinetic model (R² = 0.9964) and Koble–Corrigan isotherm (R² = 0.9705). Thermodynamic studies showed that the adsorption process is spontaneous (ΔG⁰ < 0), endothermic (ΔH⁰ > 0) in nature, and leads to an increase in randomness at the solid–solution interface (ΔS⁰ > 0). © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45924.     

One pot blending of biopolymer‐TiO2 composite membranes with enhanced mechanical strength

A biopolymer‐TiO₂ composite membrane was prepared by blending of N‐[(2‐hydroxy‐3‐trimethylammonium) propyl] chloride chitosan and cellulose acetate with nano‐TiO₂ particles as the introduced inorganic components. It was verified that the amino groups (? NH₂) of chitosan (CTS) were partly grafted by stronger hydrophilic group ? according to the ¹H‐nuclear magnetic resonance spectra of N‐[(2‐hydroxy‐3‐trimethylammonium) propyl] chloride chitosan and attenuated total reflectance Fourier transform infrared spectroscopy. The structure, microcosmic morphology, water flux, swelling properties, and thermal stability of the composite membranes were characterized. With the mass ratio of cellulose acetate to CTS being 50 wt %, the mole ratio of CTS to glycidyl trimethylammonium chloride being 1 : 1, and drying temperature being 60°C in 70% acetic acid, the formed biopolymer‐TiO₂ composite membranes exhibited enhanced mechanical strength (84.29 MPa), lower swelling degree (101.36%), and improved antibacterial activity against Gram‐negative Escherichia coli (Rosetta and DH5α) and Gram‐positive Bacillus subtilis. The existence of nano‐TiO₂ particles and the introduction of stronger cationic group synergistically improved the antibacterial properties of the biopolymer‐TiO₂ composite membranes. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42732.     

Multiple Shape Memory,Self‐Healable,and Supertough PAA‐GO‐Fe3+ Hydrogel

A multiple shape memory and self‐healing poly(acrylic acid)‐graphene oxide‐Fe³⁺ (PAA‐GO‐Fe³⁺) hydrogel with supertough strength is synthesized containing dual physically cross‐linked PAA network by GO and Fe³⁺. The first GO cross‐linked hydrogel can be reversibly reinforced by immersing in FeCl₃/HCl and pure water and softened by immersing in HCl. The tensile strength is 2.5 MPa with the break strain of 700%. Multiple shape memory capability is found depending on this unique feature, the hydrogel can be fixed in four temporary shapes by adjusting the immersing time in FeCl₃/HCl and pure water, and recovered in sequence by immersing in HCl. This hydrogel also exhibits perfect self‐healing behavior, the cut as‐prepared hydrogel is almost completely healed by immersing in FeCl₃/HCl. Besides, the hydrogel shows enhanced electrical conductivity with the presence of GO and Fe³⁺. This supertough hydrogel provides a new way to design soft actuators.

     

Indirect effect of polyvinylpyrrolidone and cetyltrimethylammonium bromide on UV‐blocking efficiency of TiO2@PVP‐CTAB@SiO2 core‐shell nanohybrid particles

In this study, a novel and useful approach to fabricate @PVP‐CTAB@ (TPS) nanohybrid as an effective light stabilizer agent has been reported. Also, the indirect role of the Polyvinylpyrrolidone and cetyltrimethylammonium bromide on UV (ultraviolet) protection properties of nanohybrid particles was investigated. In addition, comparative studies were carried out to evaluate the photocatalytic and UV protection properties of @ (TS), commercial (US3490), synthesized nanparticles, and TPS nanoparticles. Furthermore, the UV protection property of 2‐(2H‐benzotriazol‐2‐yl)?4, 6‐bis (1‐methyl‐1‐phenylethyl) phenol, as an organic anti UV, was also compared with TPS nanoparticles. The as prepared nanohybrid was characterized by Fourier transform infrared spectroscopy, zeta potential, field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), and UV‐Vis spectroscopy. FESEM and TEM micrographs show monodispersity and nano‐metric size of TPS. Rhodamine B degradation study clearly shows that TPS present the lowest photocatalytic property. Also, UV‐Vis spectroscopy results show that the TPS nanoparticles illustrate higher UV blocking ability comparing to other presented anti UV materials. TPS with convenient and useful synthesis method, high UV blocking ability, and little effect on polymer matrix can be introduced as a novel UV‐blocking agent in polyurethane matrix. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44148.     

Development of Ageing Resistant and Bioactive t‐ZrO2 Polymorph by the Combined Additions of Ca2+, and SiO2

The combined additions of Ca²⁺ and to the SiO₂–ZrO₂ system were attempted through in situ sol–gel technique. Six different combinations were synthesized and the results were compared with pure SiO₂–ZrO₂ system. The synthesized materials were subjected to accelerated leaching tests to evaluate their phase degradation behavior, nanoindentation for mechanical analysis, and immersion tests in simulated body fluids (SBF) to test their apatite forming ability. The results confirmed the phase stability of t‐ZrO₂ till 1100°C and the presence of SiO₂, Ca²⁺, and in t‐ZrO₂ matrix exhibited good apatite forming ability during SBF immersion and their reluctance in phase degradation during accelerated leaching tests. However, the values of hardness and Young's modulus were found inferior in comparison with the commercial t‐ZrO₂ products.     

Electrical properties and the role of inhomogeneities at the polyvinyl alcohol/n‐inp schottky barrier interface

In this work, we have investigated the electrical properties of Au/n‐InP contacts with a thin layer of polyvinyl alcohol (PVA) as an interlayer. The current–voltage (I–V) and capacitance–voltage (C–V) measurements are carried out in the temperature range of 175–425 K. The Au/PVA/n‐InP Schottky structure show nonideal behaviors and indicates the presence of a nonuniform distribution of interface states. The temperature dependent interface states densities (N_SS), ideality factor and barrier height are obtained. An abnormal decrease in zero‐bias barrier height (BH) and increase in the ideality factor ( ) with decreasing temperature have been explained on the basis of the thermionic emission theory with Gaussian distribution (GD) of the BHs due to the BH inhomogeneities. The experimental I–V characteristics of Au/PVA/n‐InP Schottky diode has revealed the existence of a double GD with mean BH values of ( ) of 1.246 and 0.899 eV and standard deviation ( ) of 0.176 and 0.137 V, respectively. Consequently, the modified conventional activation energy versus plot gives and Richardson constants ( ) and the values are 1.17 and 0.71 eV and 9.9 and 6.9 A/cm² K², respectively, without using the temperature coefficient of the BH. The effective Richardson constant value of 9.9 A/cm² K² is very close to the theoretical value of 9.4 A/cm² K² for n‐InP. The discrepancy between Schottky barrier heights estimated from I–V and C–V measurements is also discussed. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39773.     

Preparation and characterization of core‐shell polystyrene/polyaniline/Pd composites and their catalytic properties for the reduction of 4‐nitrophenol

Herein, polystyrene/polyaniline/Pd (PS/PANI/Pd) core‐shell composite catalysts were prepared by a facile swelling‐diffusion‐interfacial polymerization method. PS microparticles were firstly prepared by dispersion polymerization and were swollen by aniline monomer without any surface modification. H₂PdCl₄ acid was used as palladium precursor. The was adsorbed on the surface of aniline‐swollen PS microparticles because of the electrostatic attraction between and anilinium positive ions protonated by H⁺, which was diffused from the aniline‐swollen PS microparticles. Then HCl solution was added to control the diffusion rate of anilinium positive ions and ammonium persulfate (APS) was used to polymerize the anilinium ions to get PANI shell. Due to the redox activity between PANI and Pd ions, Pd nanoparticles can be in situ formed on the surfaces of PS. Therefore, the core‐shell PS/PANI/Pd composite catalysts were obtained. The morphology and structure of the obtained composites was characterized by TEM, FT‐IR and EDX. Results showed that the products presented excellent catalytic properties for the reduction of 4‐nitrophenol (4‐NP) to 4‐aminophenol (4‐AP) in the presence of NaBH₄ by virtue of the interaction between Pd nanoparticles and conducive PANI shell. The catalytic reaction obeyed the pseudo‐first‐order reaction equations and the reaction rate constants were also calculated in this article. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44812.