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The present paper reports a continuous microfluidic approach for the preparation of microcapsules (MCs), by interfacial polymerization, with a polyurea/polyurethane (PUa/PU) shell containing isophorone diisocyanate (IPDI). The microfluidic system enables the formation of a monodisperse oil-in-water (O/W) emulsion by a separate flow of the reagents along the tubing system, which posteriorly meet at a cross-junction, resulting in the precise formation of one emulsion droplet at a time. The developed MCs are intended to be part of a new monocomponent, autoreactive and ecological adhesive, as cross-linking agents. Critical operational parameters in the microfluidic process were investigated, namely the flow rate of the emulsion phases, the cross-junction’s configuration and its correlation with the MCs’ morphology, average diameter, size distribution and amount of encapsulated isocyanate. The advances achieved in the current study represent a contribution to the development of new sustainable and eco-friendly products, where the employment of monodisperse MCs is an advantage.

In this paper, an efficient thin-film nanocomposite (TFN) membrane was synthesized by interfacial polymerization and used for water desalination. Piperazine (PIP) and trimesoyl chloride were used as monomers, and p-phenylenediamine-grafted multi-walled carbon nanotube (p-PDA-MWCNT) was used as a hydrophilic modifier to enhance the performance of the polysulfone nanofiltration membrane. In order to characterize the synthesized p-PDA-MWCNTs, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis and electron-dispersive spectroscopy were used. In order to enhance the performance of the membrane, different concentrations of p-PDA-MWCNTs (0.01, 0.02, 0.04, 0.05 and 0.075 wt%) were added to the PIP solution to prepare p-PDA-MWCNTs-embedded membranes. To check the performance of the modified membrane, solutions of 1000 mg L−1 Na2SO4, MgSO4, NaCl and CaCl2 were tested. The results show that TFN-modified membrane provides excellent water permeability and also salt rejection in the presence of 0.02 wt% p-PDA-MWCNTs which shows superior improvement in TFN membrane.

Low-pressure nanofiltration membrane produced by FILMTEC-DOW is generally considered by membrane industries as the commercial standard; according to its specification, for a 2000 ppm MgSO4(aq) feed, it yields 98.2% MgSO4 rejection and 22 GFD permeate flow at 70 psi applied cross-flow filtration pressure. Here we want to report our nanofiltration membrane development works on improved reactant formulation and fabrication process to produce our nanofiltration membrane having 98.2% MgSO4 rejection and 33 GFD permeate flow for the similar test conditions as FILMTEC-DOW did. Our near 50% improvement on water permeate flux over FILMTEC-DOW low-pressure nanofiltration membrane was due to the fact that an adduct salt named TEACSA was added to the aqueous piperazine aqueous solution during our membrane fabrication process. Besides evaluating the nanofiltration performances of our NF membranes, characterizations of the polyetherimide (PEI) microporous supports fabricated in our laboratory in the areas of pure water permeate fluxes at 40 psi cross-flow filtration pressure, wet–dry studies of hydrophobic porous polyetherimide and polysulfone supports, AFM and SEM were performed.

In-situ interfacial polymerization method was employed to synthesize nanocomposites based on a semi-aromatic polyamide (PA) and pristine or sulfonated graphene oxides (GO or SGO, respectively). The PA chains were produced at the interface of a nonaqueous solution of isophthaloyl dichloride and an aqueous triethylenetetramine solution containing different amounts of GO or SGO dispersed nanosheets. The effects of SGO and pristine GO on the structure, thermal stability and dynamic mechanical and electrical properties of PA were studied. Favorable interfacial interactions between SGO and PA were confirmed using Fourier transform infrared spectroscopy and X-ray diffractometry. Consequently, SGO significantly increased the thermal stability and char residues of PA. Furthermore, adding both pristine and sulfonated GO nanosheets led to an enhancement in storage modulus and a shift in glass transition temperature of the polyamide. Finally, the facile sulfonation of GO resulted in partial reduction of the electrically insulating nanosheets and hence the electrical conductivity and dielectric constant of PA were increased by 10 and 3 times, respectively, at SGO content of 1.0 wt%.

Novel polyimide nanofiltration membranes were prepared by interfacial polymerization using 1,2,4,5-benzene tetracarbonyl chloride (BTC) and trimesoyl chloride solution in n-hexane and aqueous solution of ethylene diamine on electrospun PVDF support followed by thermal treatment. The BTC was synthesized by the reactions of 1,2,4,5-benzene tetracarboxylic acid with thionyl chloride using triethylamine as a catalyst. The polyimide layer prepared by optimized conditions such as temperature, heating time and interfacial polymerization method found to be good for performance of selective layer. Optimized conditions are confirmed from scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis–differential thermal analysis and differential scanning calorimetry studies. The NF membrane containing polyimide selective layer exhibited 7 ‘gallon/ft2 day’ water flux and ‘94.8%’ salt rejection. Although the salt rejection values of these polyimide membranes were close to the commercial NF polyamide membranes, these membranes exhibited high chlorine resistance. After chlorination for 100 h in a 200 ppm NaClO solution, polyimide membrane showed 1.4% increased flux and about 2.2% decline in salt rejection.

In this paper, we demonstrate a simple approach to improve the electrochromic performances of polyaniline (PANI) by incorporating PANI nanofibers (PANI-NFs) synthesized by interfacial polymerization into water-soluble PANI:poly(styrene sulfonate) (PANI:PSS). The one-dimensional PANI-NFs endow spin-coated PANI film high electrochemical activities and electrochromic properties. The structures and morphologies of PANI-NFs were characterized by FTIR spectroscopy and SEM observation. The electrochemical behaviors of PANI/PANI-NFs composites were analyzed by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The electrochromic properties of composites were tested using electrochemical working station combining a UV-Vis spectrometer. The results show that the PANI-NFs with even diameter of ~ 30 nm can be synthesized easily using interfacial polymerization method. With the increasing of feeding amount of PANI-NFs, the oxidation peaks of CV curves shift to low potential direction, indicating enhanced electrochemical activities. The electrochromic test confirms that the PANI/PANI-NFs composites films have higher electrochromic contrast of 0.67 as comparison to 0.49 of PANI:PSS film. The PANI/PANI-NFs also exhibit excellent electrochromic stability. After 2000 cycles switching, only less than 4% contrast decay is observed. The enhanced electrochromic properties can be attributed to the small charge-transfer resistance and facile ion diffusion process brought by PANI-NFs. The EIS tests exhibit that with incorporating of highly conductive PANI-NFs, the PANI/PANI-NFs composites possess relatively lower charge-transfer resistance of 76 Ω as comparison to 94 Ω of neat PANI:PSS.

The effect of the incorporation during the interfacial polymerization process of copper-oxide (CuO) nanoparticles in thin-film composite (TFC) reverse osmosis (RO) membrane on their antibiofouling and desalinization performance have been studied. Membranes were characterized by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM), zeta potential and contact angle measurements. Bactericidal tests were performed using Escherichia coli and anti-adhesion properties were confirmed by fluorescence microscopy. Membrane performance using a cross flow cell was evaluated. XRD and SEM–EDX analyses confirmed the incorporation of these nanoparticles into the membrane. Similar contact angle, higher surface roughness and less negatively charged surface on modified membrane compared to that of the pristine membrane were observed. However, an excellent anti-adhesion and bactericidal effect were observed, mainly attributed to the copper toxicity. The desalination performance of the modified membrane showed an important salt rejection with stable water flux. In conclusion, the incorporation of CuO nanoparticles into TFC-RO membranes during the interfacial polymerization process is a potential alternative method to improve the antibiofouling capacities without impairing the performance of the membrane.

A novel group of microcapsule-based self-healing systems for epoxy coatings was developed. Microcapsules with polythiourethane shell wall were synthesized via interfacial polymerization from selected diisocyanates and thiols and dispersed in epoxy matrix. The obtained composites were tested for their self-healing efficiency using three-point bending test (TPBT) and scratch test. Two sets of each composite samples as well as reference (neat diglycidyl ether of bisphenol A epoxy with polyamine adduct hardener) were tested with TPBT using two methods. Standard method according to ISO 178 was applied for the first set and custom method with pre-bending with 20 N force and standard TPBT after 24 h of self-healing—for the second set. Pre-bending was applied to obtain microcracks (without sample cracking) for internal self-healing process occurrence. Scratch test allowed to evaluate self-healing efficiency at composite surface and chemical resistance of samples. FT-IR spectroscopy was conducted to confirm occurrence of self-healing process based on polyurethane secondary network forming.

A series of novel epoxy polymer shell microcapsules with n-tetradecane and dimethylbenzene as binary core materials are successfully synthesized via interfacial polymerization. Dimethylbenzene is used as the solvent for epoxy and n-tetradecane. The chemical structure, surface morphology, and thermal properties of the microencapsulated phase-change materials (micro-PCMs) are characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and transmission electron microscope. Results show that the micro-PCMs have relatively spherical profiles and smooth surfaces with diameters ranging from 10 to 70 μm. The epoxy shell successfully encapsulates the binary core. Phase-change enthalpy and binary core content in the micro-PCMs increase with the increasing mass ratio of the binary core to the epoxy resin. The micro-PCMs degrade in two steps, and the resulting microcapsules exhibit good thermal stabilities. The degradation temperature decreases, as the core-to-shell mass ratio increases.

An interfacial polymerization reaction was used to coat functional paper with a polyurea film containing N,N-diethyl-3-methylbenzamide (DEET). Preparation of the polyurea film via an interfacial polymerization reaction eliminated the need for microcapsule preparation and coating with a binder, which are processes that are typically required for functional paper preparation. Interfacial polymerization involved the immersion of a sheet of filter paper impregnated with an oil-in-water emulsion of ethylenediamine (EDA) and DEET in a cyclohexane solution of hexamethylene diisocyanate. This fixed the polyurea film that contained the DEET on the paper surface. The amount of DEET fixed on the paper depended on the EDA concentration, and the maximum amount of DEET fixed was 18.65 mg/m2 for 10 % EDA. The percent content of residual DEET after 72 h on the blank paper was 6.0 %, whereas that for paper prepared using 2.5, 5, and 10 % EDA was 81.4, 73.2, and 57.1 %, respectively. The functional paper prepared in this study could provide for the sustained release of DEET from the paper surface.

The water-soluble terpolymers were synthesized in two steps, containing esterification of polyethylene glycol (PEG) and 4-amino benzoic acid without protection of its amino group, then copolymerization of aniline from both end of amine-terminated PEG via an interfacial polymerization method. The chemical structure of triblock copolymers was determined by FTIR and 1HNMR. The thermal behavior, morphology and electroactivity of terpolymers were also investigated by thermogravimetric analysis, field emission microscope (FESEM) and cyclic voltammetry (CV), respectively. Uniform nanofibers consisting of blends of (PANI)n-b-PEG-b-(PANI)n terpolymers and polycaprolactone (PCL) were prepared using electrospinning technique. The FESEM was also used to investigate the electrospun nanofibers produced from different molecular weight of PANI/PEG/PANI terpolymers and PCL (30/70). The CV measurements of blends confirmed the preparation of electroactive nanofibers. The presence of terpolymers enhanced the spinnability of solution and significantly reduced the bead formation. This novel system opens up new and interesting opportunities for applications such as electroactive scaffold for tissue engineering.

Eight novel polyhydrazides (PHa4–h3) were prepared from the reaction of two novel diacids, 5-(2-(6-methyl pyridine-2-yl)-1,3-dioxo isoindoline-6-carboxamido) isophthalic acid (3) and 5-(2-(4-methyl pyridine-2-yl)-1,3-dioxo isoindoline-6-carboxamido) isophthalic acid (4), with four dihydrazides by interfacial polycondensation. These polymers have moderate inherent viscosities (0.12–0.17 dL/g) and are readily soluble in polar aprotic solvents. They start to decompose (T10%) above 187 °C and display glass transition temperatures in the range of 130.3–156.3 °C. All polymers could be thermally converted into the corresponding polyoxadiazole approximately in the region of 250 °C, as evidenced by the DSC thermograms. All of the above polymers were fully characterized by FT-IR and 1HNMR spectroscopy, TGA, DSC, and inherent viscosity measurement.

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.

A new optically active poly(ester-imide) (PEI) was synthesized from the interfacial polymerization of Ethyl l-lysine-N,N′-ditrimellitoyl diacyl chloride with bis phenol A. Ultrasonic irradiation was applied to compose nanocomposites from the synthetic polymer and different ratios of organo-modified montmorillonite (MMT). The formation of PEI was confirmed by 1H NMR, FT–IR spectroscopy, specific rotation, and elemental analysis. The resulting nanocomposites were characterized by FT–IR, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The results indicated that the composites were dispersed homogeneously in PEI matrix on nanoscale. An improvement in heat stability is indicated from TGA analysis.

The polyamide microcapsules for the electrophoretic display have been prepared via interfacial polymerization. The core material of the microcapsules is electrophoretic fluid consisted of pigment phthalocyanine green G (CAS No. 1328-53-6) modified with octadecylamine, tetrachloroethylene, and polyoxyethylene octylphenol ether (OP-10). The wall of the polyamide is synthesized from paraphthaloyl chloride and diethylenetriamine. FT-IR indicated that octadecylamine was bonded to pigment phthalocyanine green G with the hydrogen bond. The effect of the amount of octadecylamine on the dispersibility of the pigment suspended in tetrachloroethylene was investigated. Compared to the unmodified pigment, the dispersibility of the modified pigment was improved by 66.7%. The modified pigment migrated to the positive electrode under the direct voltage and the electric response time was about 85 s in 20 V/mm. The average particle size of microcapsules decreased from 834.5 to 258.2 nm as the dosage of OP-10 increased, and the microcapsule yield reached maximum of 83.5% at the OP-10 concentration of 1.5 wt%. With the reduction of the core/wall weight ratio in the range from 1:6 to 1:14, the average particle size improved from 267.4 to 554.4 nm. However, the maximum of the microcapsule yield was 87.6% at the core/wall weight ratio of 1:10. The microcapsule yield reached a peak of 87.6% as the pH value was 12. The average particle size of the microcapsules that obtained at 25 °C was 327.4 nm, which was smaller than those prepared in other temperatures. The formed polyamide microcapsules had a regular spherical shape.

Microcapsules containing tetrachloroethylene as an internal phase were prepared by in situ polymerization of urea–formaldehyde (UF) without prepolymerization. The effects of different emulsifiers on the process of microencapsulation and morphology of microcapsules were investigated. The results show that the emulsifier gum arabic (GA) can effectively slow down the deposition rate of resin onto the oil/water interface, which can lead to smooth and compact surface of microcapsules. The surface activity of GA was also enhanced by complex formation of gum arabic and sodium dodecyl benzene sulfonate. The microcapsules represent good thermal and barrier property as a result of the formation of capsule wall with compact microstructure.

The reaction of phenylphosphonic dichloride with 4,4′-cyclohexylidenebisphenol by a gas–liquid interfacial polycondensation was investigated. The design of experiments (DoE) method is used for determination of the best reaction conditions. The correlation of simultaneous influence of the parameters (reaction time, reaction temperature, alkaline medium, reagents molar ratio) on yield and inherent viscosity was studied.

Polyphosphonates, polyphosphates, polyarylazophosphonates and polyarylazophosphates were synthesized by a new alternative to the classical phase transfer catalysis, respectively, the modified inverse phase transfer catalysis (IPTC) polycondensation of various phenylphosphonic (phosphoric) dichlorides (phenylphosphonic dichloride, phenylphosphoric dichloride, p-chlorophenylphosphoric dichloride) with bisphenols: bisphenol A, tetrabromobisphenol A, bis-(4-hydroxyphenyl)methane (bisphenol F), 4,4′-dihydroxyazobenzene. The polymers were characterized by infrared spectroscopy and magnetic resonance (1H-NMR, 31P-NMR, 13C-NMR) spectroscopy. Yields in the range of 63.5–85% and molecular weights (M w) of ~2,000–8,200 g mol−1 were obtained. Polyphosphonates were stable up 210–270 °C and polyphosphates up 190–220 °C in air atmosphere. For a correct estimation of the thermal behavior of similar compounds, a kinetic analysis using a modified version of Non Parametric Kinetic method for representative polyphosphonate and polyphosphate was realized. The studies made on the hydrolytic degradation of the synthesized polyphosphates show that the most stable polymer under alkali-catalyzed degradation is the polyphosphate obtained by IPTC of phenylphosphoric dichloride and bisphenol A.

A new method to prepare a kind of double layered microcapsules was developed. Polyurea (PU) microcapsules were firstly fabricated by interfacial polymerization as inner layer, on which urea-formaldehyde (UF) resin was coated to form a protective outer layer by in-situ polymerization. Environmental scanning electron microscope, optical image analyzer, Fourier transform infrared spectrophotometer and thermo gravimetric analysis were employed to investigate their characteristics for the morphologies, particle size, materials structures and thermal properties. The prepared double layered PU-UF microcapsules are mono-dispersed with ultra-thick capsule wall and improved thermal stability.

A series of aromatic polyesters, were synthesized under phase transfer conditions. The copolymers were obtained in an essentially quantitative yield. These polyesters were soluble in chloroform and readily form clear, colorless films from solution. The optimum conditions of polymerization were obtained via interfacial polymerization at room temperature and with a reaction time of 4 h in chloroform. All polymers were characterized by FTIR, GPC, viscosity, water contact angle, water absorption, TGA, DSC, X-ray, and NMR. The structures of the polymers were confirmed by NMR and FTIR spectroscopy. The prepared polyesters showed excellent thermal stability as measured by TGA (10% wt. loss) is moderate and ranges from 438 to 473 °C in argon, glass transition temperatures are between 147 and 215 °C, water contact angles for these polymers ranged were from 74° to 90°, Inherent viscosity values range obtained from 0.35 to 1.3 dL.g-1 and Mw values range from 30.5 to 159×103.

The capsules containing magnetite has been used in several applications. Conventional methods for preparing capsules containing magnetite have not achieved a high rate of magnetite content. In this research, we succeeded in preparing capsules containing a high proportion of magnetite with a new method that uses a magnetic field. These capsules are prepared by interfacial polymerization of polyamide. The capsule size is controllable in the approximate range of 20-1000 μm. The method can possibly be used for even smaller capsules with improvement of apparatus. Calculation of density showed that the capsules contained magnetite at a rate of 50% or more. They are believed to be easily mass-produced and their industrial application is expected.

Nanocapsules were prepared by interfacial polycondensation of an oil-soluble monomer (phthaloylchloride) and a hydrophilic monomer (diethylentriamine). Upon addition of the oil phase to the aqueous phase, interfacial reaction takes place at the interface of an oil in water submicronic emulsion. After the initial formation of the wall, the polycondensation is diffusion controlled. The influence of different variables on nanocapsules size was evaluated. Oil (Miglyol® 812) concentration played an important role by controlling the size of the emulsified droplets (precursor of nanocapsules). Ratio of lipohilic to hydrophilic monomer showed a significant effect on the size, indicating that polymeric walls of difference thicknesses can be obtained. The introduction of a lipohilic surfactant (Lipoid® S75) and a hydrophilic surfactant (Pluronic®F68) in the formulation is important for the stability of nanocapsules after their preparation.

A series of polyphosphonates were synthesized by base promoted liquid-vapor interfacial polycondensation of various alkyl (aryl) phosphonic dichlorides (methylphosphonic dichloride (MPD), cyclohexylphosphonic dichloride (CPD) and phenylphosphonic dichloride (PPD)) with different bisphenols (hydroquinone (HQ), bisphenol A (BA), 4,4′ - biphenol (BP), 1,5-naphtalenediol (ND) and 4,4′ - sulfonyldiphenol (SD)). The polyphosphonates were characterized by infrared (IR) and proton magnetic resonance (1H-NMR) spectroscopy. Yields in the range of 20–80% and Mn of ∼ 8500–35000 were obtained. DSC measurements show Tg in the range 95°–148°C. These polymers are soluble in solvents such as N,N-dimethylformamide, tetrahydrofuran and chloroform. Polyphosphonates were stable up 240°–300°C in air atmosphere.

Polyphosphonate esters of molecular weights ∼ 104 were synthesized by base promoted liquid-vapor polycondensation of cyclohexylphosphonic dichloride with bisphenol A. The effect of temperature, reaction time, base concentration and molar ratio of reagents on yield, inherent viscosity and molecular weight of the obtained polymer was studied. A second order, central composite, rotatable experimental design was used to find domain experimental field for optimal yields and high inherent viscosities.

New aromatic polyester was synthetized by polycondensation of indane-1,3-diol and terephthaloyl chloride. The indane-1,3-diol was synthesised by metal hydride reduction and characterized by IR, 1H and 13C NMR. Two polycondensation methods was used : solution and interfacial polycondensation in presence of various quaternary ammonium salts. The obtained polymers were characterized by differential scanning calorimetry (DSC) and viscosities measurements. All polymers had glass transition temperature (Tg) in the range of 72–77°C and melting temperature (Tm) in the range of 152–184°C.

Poly(amide-ester)s, poly(amide-carbonate)s and poly(amide-thiocarbonate)s derived from the diphenols-amides N-(2,6-dibromo-4-nitrophenyl)-4,4-bis(4-hydroxyphenyl)-pentanamide (I) and N-(2,6-diiodo-4-nitrophenyl)-4,4-bis(4-hydroxyphenyl)-pentanamide (II) and terephthaloyl chloride (a), isophthaloyl chloride (b), and adipoyl chloride (c), and phosgene (d) and thiophosgene (e) respectively, have been synthesized under phase transfer conditions using several quaternary ammonium salts as phase transfer catalysts. Benzyltriethylammonium chloride (BTEAC) was effective in practically all cases due to the hydrophilicity of this catalyst. Poly(amido-ester)s derived from II and aromatic diacids were insoluble in all the organic solvents, and the effectivity of the process was evaluated by the increase of the yields with respect to the essays without catalysts.

The synthesis and metal ion responsive properties of Congo Red-based polyamide are reported. The polymer was prepared by simple interfacial polymerization between Congo Red and sebacoyl chloride. The polymer showed decrease in electronic absorption when exposed to metal ions. The absorbance tends to decrease linearly in a measurable range according to metal ion concentration. It is found that the polymer showed high sensitivity toward Ca2+ and Fe3+.

Biodegradable aliphatic polyamides have been prepared from CIO and C14 dicarboxylic acids and amide-diamines containing one or two preformed amide linkages susceptible to enzymatic cleavage in their molecules. L-phenylalanine, either by itself or together with L-valine, was used to generate amide bonds which are cleavable by chimotrypsine. Improved chain flexibility and hydrophilicity of the polyamides was obtained using a triethyleneoxy based amide-diamine. Characterization of the novel monomers and polymers by FTIR and 1H-NMR spectroscopy confirms the expected structures. Thermal data and solubility tests indicate that both T m and solubility depend on the length and nature of the aliphatic segment present in the amide-diamine as well as on the “density” of interchain hydrogen bonds. Finally the polymers tested are capable of supporting fibroblast adherence and proliferation, and proved to be non cytotoxic.

Poly(amide-carbonate)s and poly(amide-thiocarbonate)s derived from the diphenol-amides N-(2,6-dichloro-4-nitrophenyl)-2,2-bis(hydroxyphenyl)-propylamide I), N-(2,6-dichloro-4-nitrophenyl)-3,3-bis(hydroxyphenyl)-butylamide (II), and N-(2,6-dichloro-4-nitrophenyl)-4,4-bis(hydroxyphenyl)-pentylamide (III), and phosgene or thiophosgene, have been synthesized under phase transfer conditions using several quaternary ammonium salts as phase transfer catalysts. Benzyltriethylammonium chloride (BTEAC) was effective in practically all cases due the hydrophilicity of this catalysts.

The current paper presents the synthesis of a new polyamide, polyethylene succinamide (polyamide 24), via interfacial and solution-solid phase polycondensation. The resulting product was characterized by means of elementary analysis, infrared spectrometry, 1H-nuclear magnetic resonance, intrinsic viscosity and differential carolimetry. The effects of polymerization conditions on molecular weight of the product and the solubility of polyamide 24 in a number of commonly used solvents were also studied.

The behavior in interfacial polycondensation of 4,4-methylenedianiline (MDA) or 4,4-oxydianiline (ODA) in water with dimethoxycarbonylterephthaloyl chloride (DCMTC) in dichloromethane with benzyltriethylammonium chloride (BTEAC) as the catalyst was examined with a Raman imaging microscope, and scanning electron microscope. The surfaces of the polymers adjacent to the water phase had higher average molecular weight than the surfaces of the polymers adjacent to the organic phase. Moreover, the morphology of the films also changed from dense to porous along the thickness direction of the films. To obtain an interfacial film more homogeneous in morphology and molecular weight, the reaction time of interfacial condensation should not exceed 5 minutes in this system. The interfacial films were anisotropic. The chain axis of the poly(amic-ester)s mainly oriented perpendicularly to the interface in the direction of membrane growth.

New polyamides were prepared by the solution polycondensation and interfacial polycondensation starting from 1,6-diaminodiamantane and aromatic diacid chlorides. The polyamides had inherent viscosities of 0.15–0.45 dL/g. The temperatures at 5% weight loss for the polyamides were between 435–475°C in nitrogen. The glass transition temperatures of the polyamides determined by DSC ranged from 245°C to 300°C. The crystallinity of the resultant polyamides was influenced by the method of polycondensation and various monomers.

New polyamides and polyesters containing spiroacetal and silphenylene units were prepared by the low-temperature interfacial polycondensation reaction of 4,4′-diaminodibenzalpentaerythritol (4-ABP) or 4,4′-dihydroxydibenzalpentaerythritol (4-HBP) with bis(4-chlorocarbonylphenyl)dimethylsilane (DMS) or bis(4-chlorocarbonylphenyl)diphenylsilane(DPS). The resulting polymers have inherent viscosities in the range of 0.13∼0.90 dL/g at 30°C in N,N-dimethylacetamide. These polymers were readily soluble in various polar solvents and were able to be cast into transparent and tough films. The glass transition temperatures of the polymers were detected in the range of 161∼253°C in their differential scanning calorimetry traces. No evidence of melting point was observed in all polymers. The solution-casted film of polyamide (PA-I) derived from 4-ABP and DMS showed ultimate strength of 73.4 MPa and initial modulus of 13.4 GPa.

A series of phenyl ring di-substituted α,α′-dichloro-p-xylene monomers were copolymerized in situ onto a cross-linked chloromethylated polystyrene resin. A phase-transfer catalyst was employed to facilitate this multiphase heterogeneous polymerization. The electrical as well as the thermogravimetric properties of the conducting grafted resins are reported.

A novel synthetic method for the preparation of high molecular weight aromatic poly- (etherketone)s is described. N-Alkyl(4-N′,N′-dialkylamino)pyridinium chlorides 1, 2 and 3 were used as phase-transfer catalysts in polycondensation reactions of 1,4-bis(4-chlorobenzoyl)benzene (4) with aromatic diphenols via nucleophilic displacement. The polycondensations were significantly promoted and, moreover, the results achieved in terms of molecular weight and reaction time were comparable to polymerizations conducted with 1,4-bis(4-fluorobenzoyl)benzene (5), which is a considerably more reactive monomer.

Polycarbonates, polythiocarbonates, and polyesters from 1, 1,3-trimethyl-3 -(4'-hydroxy-phenyl)-4-indanol were synthesized using phase transfer conditions. The effects of several catalysts and reactions times were evaluated by the yields and inherent viscosities. Phase transfer catalysis was not an efficient technique due to the rigid structure of the diphenol with the indanic group. The results were compared with that obtained with a diphenol having the same number of carbon atoms but forming an aliphatic side chain

Polyesters from 3,3'-bis (chloromethyl)oxacyclobutane and dipotassium isophthalate were obtained by phase transfer catalysis using different catalysts and solvents. The products were characterised by IR, 1 H-NMR and DSC

Multiblock and regularly alternating biodegradable polyesteramides containing amide bonds susceptible of enzymatic cleavage were prepared and preliminarly characterized by viscosity, IR, 1H-NMR and DSC techniques. L-phenylalanine was used to build up amide linkages containing a phenyl ring adjacent to the acyl group, enzymatically cleavable by chymotrypsin. Monomers having preformed ester groups or biodegradable amide bonds and/or telechelic oligomers of poly(L-lactide) were used as starting materials. Their chain length was regularly increased in order to improve the overall chain flexibility and, hence, to favour the enzymatic attack.

Liquid crystalline vinyl ethers have been bulk polymerized cationically in the mesophase using onium salts for thermal initiation. High molecular mass polymers (Mn≤83 000) with a narrow molecular mass distribution (around 2) were produced at very high temperatures (≤120°C). Apparently the polymerization system stabilizes the propagating cation and thus reduces chain transfer reactions that are determining the molecular mass. Possible reasons for this stabilization are e.g. influence of the mesophase of the formed polymer, interfacial polymerization, and nucleophilic stabilization by nucleophiles present in the monomer or produced by the initiators.