Characterization of synthesized poly(aryldisulfide) through interfacial polymerization using phase-transfer catalyst

A new polysulfide polymer was synthesized from 1,4-bis(chloromethyl)-benzene and sodium disulfide by an interfacial polycondensation technique in the presence of tetrabutyl ammonium bromide, methyltributyl ammonium chloride and benzyl triethyl ammonium chloride as phase-transfer catalysts (PTC). The effect of PTC on the kinetics of polymerization was investigated. Structures of this aromatic polysulfide were confirmed through elemental analyses, attenuated total reflectance Fourier transform infrared spectroscopy, Raman spectroscopy, an X-ray diffraction technique, and a nuclear magnetic resonance spectroscopy method. The thermal behavior of this polymer was also characterized by differential scanning calorimetry and thermogravimetric analysis. The solubility of prepared polymer was critically dependent on the identity of the solvent.     

阳离子聚丙烯酰胺水包水乳液合成

阳离子聚丙烯酰胺作为一种高分子物质,具有高效、环保和价廉等很多的优势,但不同的制备方法对水乳液絮凝剂的性能具有不同的影响。对此,以丙烯酰胺(AM)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)为单体,以分散聚合技术作为主要合成方法,以硫酸铵作为反应介质,合成一种CPAM絮凝剂,并充分讨论了不同单体总量与配比、反应温度、反应时间、硫酸铵浓度、引发剂种类等多种因素对阳离子聚丙烯酰胺的影响。最后通过红外光谱等的分析,验证了合成的阳离子聚丙烯酰胺具有较好的稳定性、流动性等特点。     

Synthesis and characterization of polycarbonates containing terminal and chain interior siloxane

Silicone polycarbonates having polydimethyl siloxane (PDMS) and heptamethyl trisiloxane (HMTS) were synthesized by the interfacial polymerization. Instead of common chain terminator p-tert-butyl phenol (PTBP), eugenol capped HMTS, and PDMS were used. PDMS was also attached into the chain interior of the polymer in different molar ratios. PDMS and HMTS were capped with eugenol through the hydrosilylation reaction using Karstedt’s catalyst. Both monohydroxy and dihydroxy terminated eugenosiloxanes were synthesized in order to use as chain terminator and interior subunit of polymer, respectively. Structural characterization and the study of the properties, such as thermal behavior, thermooxidative stability, surface morphology, wettability of the synthesized polymers were investigated. Flexibility and wettability of the synthesized polymers increases with increasing of silicone content. Polymers showed satisfactory thermo oxidative stability and transparency as good as bisphenol-A-polycarbonate.     

Polycarbazole by chemical oxidative interfacial polymerization: morphology and electrical conductivity based on synthesis conditions

Polycarbazole (PCB) was synthesized via an interfacial polymerization method using carbazole monomer and ammonium persulfate as the oxidizing agent. The effects of surfactant type (non‐ionic Tween 20, cationic cetyltrimethylammonium bromide (CTAB) and anionic sodium dodecylsulfate) and concentration on the synthesized PCB were investigated based on the roles of micelle formation. Electron microscopy images revealed various PCB morphologies depending on the surfactant type and concentration. The newly found morphological structures of the PCB were macroporous honeycomb, connected hollow sphere and smaller hollow sphere depending on the surfactant type. The highest electrical conductivity of doped PCB_CTAB obtained was 11.3 ± 0.36 S cm^?1. The electrical conductivity values of the doped PCB synthesized with CTAB were higher than that without a surfactant by three orders of magnitude. © 2016 Society of Chemical Industry     

Synthesis, characterization and morphology of polyanthranilic acid micro- and nanostructures

Polyanthranilic acid (PANA) nanofibres, nanorods, nanospheres and microspheres were synthesized by polymerization of anthranilic acid using ammonium peroxydisulfate (APS) as oxidant without hard or soft templates. Polymerization of anthranilic acid was carried out in aqueous solutions of strong (hydrochloric) and weak (acetic) acids. The influence of synthetic parameters such as oxidant, initiator, dopant acid and its concentration, redox initiator, and reaction medium on the morphology and particle size of PANA have been investigated. PANA nanofibres and nanorods were obtained via redox polymerization of anthranilic acid initiated by FeSO₄ as redox initiator. PANA nanospheres and nanofibres were also obtained when used aromatic amines as initiators. When polymerization carried out in the solution of weak (acetic) acid the microsphere morphology obtained and the particle size increase with increasing the concentration of weak acid. PANA nanorods were obtained also by polymerization of anthranilic in ethanol-water mixture unlike interfacial polymerization of anthranilic acid (in chloroform-water) that give PANA microspheres. The morphology and particle size of PANA was studied by scanning electron microscope (SEM) and transmission electron microscope (TEM). The average diameter of nanostructures obtained ≤100 nm. The optical bandgap of microspheres and nanofibers polymeric products were determined using UV-vis spectroscopic technique and found to be 2.0 eV and 1.6 eV, respectively. The bandgap decreased with decreasing the particle size. IR spectrum confirmed the structure of PANA nanofibres (synthesized with FeSO₄ as redox initiator) in emeraldine form. The thermal stability of polymer obtained was determined by thermal gravimetric analysis (TGA). The molecular weight was determined also by gel permeation chromatography (GPC).     

Effects of ammonium polyphosphate microencapsulated on flame retardant and mechanical properties of the rigid polyurethane foam

In this article, a flame retardant microcapsule ammonium polyphosphate microencapsulated by polyurea (POAPP) was successfully synthesized by interfacial polymerization method using ammonium polyphosphate (APP) as core and polyurea as shell. The microencapsulation is observed by scanning electron microscopy and characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis and hydroscopicity test, which prove the success in synthesizing microencapsulation. When the POAPP is added into rigid polyurethane foam (RPUF), the flame retardant and mechanical properties are investigated using cone calorimeter, limited oxygen index test, and compressive strength test. The PHRR of RPUF-POAPP20 decreased from 336.52 kW/m² (Ref. RPUF) to 203.84 kW/m² and the THR of RPUF-POAPP20 was only 7.6 MJ/m², which is 33.9% lower than that of Ref. RPUF. Furthermore, the limiting oxygen index of RPUF-POAPP20 reaches 24.8%, which increased by 36.3% compared to Ref. RPUF. Whereas the maximum compressive strength of RPUF-POAPP5 was 7.46 MPa, which is higher than that of RPUF-APP5.     

Soft template synthesis of poly(o-phenylenediamine) nanotubes and its application in self healing coatings

Poly(o-phenylenediamine) (PoPD) nanotubes were fabricated through chemical oxidative polymerization of o-phenylenediamine in cetyl trimethyl ammonium bromide (CTAB) microemulsion polymerization using β-cyclodextrin (β-CD). Iron (III) chloride (FeCl₃) was used as a structure directing agent as well as an oxidant. The polymer nanotubes thus synthesized were characterized by FTIR, UV–vis, NMR and XPS techniques and the surface morphology of nanotubes was analyzed by using SEM and TEM. A study has been made on the corrosion protection performance of mild steel by epoxy coating containing synthesized PoPD nanotubes using EIS technique and OCP measurements.     

The Synthesis Characterization and Polymerization of Novel Thiophene Substituted Maleimide

Ethyl 2-amino 4,5,6,7-tetrahydrobenzo thiophene-3-carboxylate maleimide (ETTCM) has been synthesized and investigated as a new thio-maleimide derivative. The structure of the prepared compounds has been elucidated by elemental and spectral analyses. The free radical polymerization of (ETTCM) has been conducted in several solvents using azobisisobutyronitrile (AIBN) as an initiator. The kinetic parameters of polymerization of ETTCM were investigated, and it was found that the polymerization reaction follows the conventional free radical scheme. The initial rate of polymerization, the overall activation energy Ea was determined (Ea = 57.013 kJmol^?1) and intrinsic viscosity was measured ([η] = 0.04 dl/g). The prepared polymer is a good chelating agent with some metal ions and a moderate antifungal and antibacterial effect. The monomer reactivity ratios for the copolymerization of ETTCM with methyl methacrylate MMA, vinyl acetate VA, and vinyl ether VE were calculated by two methods, the Kelen-Tüdös and a nonlinear method. Thermal stability of the ETTCM polymers and copolymers were investigated by thermogravimetric analysis.     

Microheterogeneous polymer systems prepared by suspension polymerization of methyl methacrylate in the presence of poly(ε‐caprolactone)

Poly(methyl methacrylate) – polycaprolactone (PMMA/PCL) microheterogeneous beads were synthesized by suspension polymerization starting from methyl methacrylate (MMA) monomer and PCL, which was synthesized by ring‐opening polymerization of ε‐caprolactone using ZnCl₂ as initiator. The resulting polymer was fully characterized by ¹H and ¹³C NMR, differential scanning calorimetry (DSC), gel permeation chromatography (GPC) and dynamic mechanical thermal analysis (DMTA). The size distribution and morphology of the resulting beads were investigated by optical microscopy and scanning electron microscopy (SEM). Moreover, blends of PMMA beads and PCL in different proportions were prepared and the morphology of the films was examined by optical microscopy. The low compatibility between PMMA and PCL was clearly evidenced through these experiments.     

Preparation and properties of amphoteric polyacrylamide by seeded dispersion polymerization in ammonium sulfate solution

Amphoteric polyacrylamide (AmPAM) was prepared successfully through seeded dispersion polymerization with acrylamide, methacrylatoethyl trimethyl ammonium chloride and acrylic acid as comonomers in ammonium sulfate solution. It was characterized by ¹H nuclear magnetic resonance (¹H NMR) and elemental analysis. The particle morphology and apparent viscosity of polymer dispersion were obtained by optical microscope and rotary viscometer, respectively. AmPAM dispersion was obtained with low apparent viscosity. The process was smooth without high viscosity stage. The data of ¹H NMR spectrum and elemental analysis indicated that all monomers had participated in the polymerization. The seeded reaction time and the mass ratio of two parts of monomers had significant effects on the dispersion polymerization. The best conditions were seeded reaction time 1.75h and the mass ratio 0.75. The apparent viscosity of AmPAM dispersion depended on the number of particles, particle size and low molecular weight polymer concentration in the continuous phase. AmPAM showed both anti‐polyelectrolyte effect and polyelectrolyte effect. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers     

Synthesis and lithographic characterization of poly[(dihydrocarveol)-co-(1,1-dimethylethyl bicyclo[2.2.1]hept-5-ene-2-carboxylate)-co-(maleic anhydride)]

A new ArF single-layer resist polymer, poly(dihydrocarveol-co-1,1-dimethylethyl bicyclo[2.2.1]hept-5-ene-2-carboxylate-co-maleic anhydride) has been synthesized by radical polymerization. The molar composition of synthesized resist polymer was confirmed by elemental analysis. The obtained molar composition was 0.25:0.35:0.40. This resist polymer was found to be stable up to 230 °C, but above 250 °C it underwent rapid thermal deprotection of the tert-butyl groups by releasing carbon dioxide and 2-methylpropene. The deprotection temperature was established by DSC and TGA. Using the resist, 0.14 µm L/S pattern was obtained at 26 mJ/cm⁻² doses, using an ArF stepper and the developer of 2.38 wt% tetramethyl ammonium hydroxide aqueous solution. © 1999 Society of Chemical Industry     

Electrochemical polymerization and characterization of polyether‐substituted aniline derivatives

New compounds consisting of aniline units linked by polyether bridges have been synthesized and their electrochemical polymerization was performed via constant potential electrolysis and cyclic voltammetry in an aqueous solution containing 3.0 mol L^?1 H₂SO₄. Chemical polymerization was carried out using (NH₄)₂S₂O₈ as oxidizing agent. It was found that both methods gave the same polymer product without any cleavage of the polyether bridge between aniline rings. The polymers were characterized using the Fourier transform infrared spectroscopic technique and the thermal behavior of electrochemically prepared polymers was investigated using thermogravimetric analysis. Spectroelectrochemical properties of the films were investigated using the in situ UV‐visible spectroscopic technique. Copyright © 2007 Society of Chemical Industry     

Polymerization of allyl methacrylate with wool fabric using different initiators

Polymerization of allyl methacrylate (AMA) with wool fabrics using different initiators, namely, potassium persulphate, Fe²⁺? H₂O₂, benzoyl peroxide, ceric ammonium nitrate, and vanadium pentanitrate, was investigated. The percent of polymer add-on depends upon the type and concentration of the initiator. Addition of metallic salts such as Fe³⁺ to the polymerization system enhances polymerization significantly when benzoyl peroxide and potassium persulphate are used independently as initiator. The opposite holds true for ceric ammonium nitrate and vanadium pentanitrate. With Fe²⁺? H₂O₂, on the other hand, the enhancement is marginal. Also studied was the incorporation of Li⁺, Cu⁺⁺, and Fe³⁺ at different concentrations in AMA—wool–benzoyl peroxide polymerization systems. Determination of the polymer add-on on the basis of double bond analysis revealed that the remained double bond is governed by the magnitude of the polymer add-on as well as by the type of initiator.     

Synthesis and Characterization of Poly(acrylic acid)/modified Bentonite Superabsorbent Polymer

A novel poly(acrylic acid)/modified bentonite superabsorbent polymer (SAP) was synthesized through chemical crosslinking by a polymerization technique in a complete aqueous environment. This SAP was fabricated effectively by dispersing modified bentonite in a monomeric solution, using N,N′-methylenebisacrylamide as crosslinker and ammonium persulfate as initiator. Fourier transform infrared (FTIR) spectral analysis showed that the XG chains had intercalated into bentonite sheets. The influence of crosslinking density and XG content were investigated. Results showed modified bentonite not only effectively increases water absorbency, but also improves water retention ability. This can be further used as a carrier matrix for the development of a drug delivery system.     

Synthesis, characterization polymerization and antibacterial properties of novel thiophene substituted acrylamide

Ethyl 2-acrylamido-4,5,6,7-tetrahydrobenzo [b] thiophene-3-carboxylate (ETTCA) has been synthesized and its structure has been elucidated by elemental analysis and spectral tools. Free radical polymerization of (ETTCA) has been conducted in several solvents using azobisisobutyronitrile (AIBN) as an initiator. The kinetic parameters of polymerization of the ETTCA were investigated, and it was found that the polymerization reaction follows the conventional free radical scheme. The overall activation energy of polymerization ΔE was determined (ΔE = 45.11 kJ mol⁻¹). The copolymerization of ETTCA with three conventional monomers was carried out in dioxane at 65 °C. The monomer reactivity ratios for the copolymerization of ETTCA with methyl methacrylate (MMA), vinyl acetate (VA) and vinyl ether (VE) were calculated. Thermal stability of the ETTCA polymer and its copolymers were investigated by thermogravimetric analysis. It has been found that the prepared polymer (PETTCA) and its copolymers with VA have moderate biological activity and highly dependent on the copolymer composition.     

Synthesis of azobenzene-functionalized star polymers via RAFT and their photoresponsive properties

Azobenzene-functionalized star polymers were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. First, azobenzene-functionalized linear macro chain transfer agents (Macro-CTA) were synthesized by RAFT polymerization of 6-[4-(4′-Methoxyphenylazo)phenoxy]hexylmethacrylate (MAz6Mc) using 2-(2′-cyanopropyl)dithiobenzoate (CPDB) as RAFT agent in presence of AIBN as initiator in anisole. Subsequently, star azopolymers were synthesized by polymerization of a difunctional azomonomer, BMA2Az, with resultant Macro-CTA in presence of AIBN as initiator in anisole. Star azopolymers were characterized by GPC and spectroscopic methods. Thermal properties of star azopolymers were determined by DSC and TMA. Molecular weight versus conversion and molecular weight versus polymerization time attest to living polymerization characteristics. Photoisomerization behaviors of star azopolymers were studied by irradiation of both UV and visible light. Surface relief gratings were inscribed on star azopolymer films upon exposure to an interference pattern of (RCP + RCP) Ar⁺ laser. A diffraction efficiency of 20% was obtained by exposure of Star-8 K(2.6 K) polymer film to an (RCP + RCP) Ar⁺ laser for about 30 min. Surface relief grating structures were investigated by AFM and polarized optical microscopy.     

Nanoporous well‐defined reversible addition–fragmentation chain transfer polymer of N‐acrylamido‐l‐tryptophan: synthesis and characterization

A nanoporous polymer with a chiral pendant chain of N‐acrylamido‐l ‐tryptophan was synthesized through a reversible addition–fragmentation chain transfer polymerization process using a dithiobenzoate derivative as chain transfer agent. The polymerization exhibited the usual characteristics of living processes, though slow polymerization rate and low percentage conversion for a chain extension experiment were observed. Depending on the monomer/chain transfer agent ratio, poly(N‐acrylamido‐l ‐tryptophan) with number‐average molecular weights between 640 and 4340 g mol^?1 and molar mass dispersities between 1.10 and 1.24 was obtained, as evidenced from gel permeation chromatography. Scanning electron microscopy images indicated that the polymer was porous. Nitrogen adsorption analysis of the polymer evidenced the presence of mesopores (2–19 nm) associated with micropores (0.45–2 nm) according to the Barrett–Joyner–Halenda method with a specific Brunauer–Emmett–Teller surface area of 22.98 m² g^?1. © 2013 Society of Chemical Industry     

聚苯胺季铵盐的合成及其性能研究

以邻氨基苯甲酸为原料,与氯乙醇反应生成2-氨基苯甲酸氯乙酯,然后用三乙胺季铵化合成了苯胺季铵盐,并将其聚合,通过红外光谱、紫外-可见光谱、X-射线衍射、循环伏安法和热重分析等对其结构与性能进行了研究。     

Synthesize of polymer–silicate nanocomposites by in situ metal‐catalyzed living radical polymerization

Polymer–silicate nanocomposites were synthesized with atom transfer radical polymerization (ATRP). An ATRP initiator, consisting of a quaternary ammonium salt moiety and an α‐phenyl chloroacetyl chloride moiety, were intercalated into the interlayer spacings of the layered silicate. Subsequent ATRP of styrene with CuCl/2,2′‐bipyridine (bipy) as the catalyst with the initiator‐modified silicate afforded homopolymers with predictable molecular weights and low polydispersities, both characteristics of living radical polymerization. The polystyrene nanocomposites contained both intercalated and exfoliated silicate structures. The prepared materials were characterized by XRD, SEM, TEM, FTIR, and ¹H NMR techniques. Effect of silicate on thermal properties and glass transition temperature of polystyrene was investigated using thermogravimetric analysis and differential scanning calorimetric techniques. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers     

Waterborne acrylic–polyaniline nanocomposite as antistatic coating: preparation and characterization

An antistatic and electrically conductive acrylic–polyaniline nanocomposite coating was successfully synthesized by interfacial polymerization of aniline in the presence of acrylic latex. The acrylic latex was prepared through emulsion polymerization, and aniline was polymerized by in situ interfacial polymerization at the interface of acrylic latex/chloroform phase. Fourier transform infrared spectroscopy (FTIR), UV–Vis spectroscopy and CHNS elemental analysis revealed the existence of 6.24 wt% emeraldine salt of polyaniline (PAni) in the dried film of the nanocomposite. Scanning electron microscopy (SEM) confirmed the presence of colloidal polymer particles in the aqueous phase which was confirmed to have some advantages, including prevention of aggregation of particles, dispersibility improvement and enhancement of the PAni nanofibers aspect ratio in the acrylic polymer matrix. According to SEM results, PAni fibers with the length ranging from 12 to 67 µm and diameters between 0.078 and 1 µm, highly dispersed in the acrylic polymer matrix, were successfully synthesized. Thermal, electrical and mechanical properties of the acrylic copolymer were significantly affected by PAni incorporation. The onset degradation temperature in thermogravimetric analysis revealed that the thermal stability of the nanocomposite was improved compared to that of the pure acrylic copolymer. The nanocomposite film showed electrical conductivity of about 0.025 S/cm at room temperature, along with satisfactory mechanical properties, attractive as an antistatic material in coating applications.