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Abstract Fixed dose combinations (FDCs) incorporating two or three medicines in a single inhaler have been created to enhance patient compliance and hence clinical outcomes. However, the development of dry powder inhalers (DPIs), particularly for FDCs, faces challenges pertinent to formulation uniformity and reproducibility. Therefore, this project aimed to employ nanotechnology to develop a FDC of DPIs for market-leading medicines—fluticasone propionate (FP) and salmeterol xinafoate (SAL)—for asthma management. Nanoaggregates were prepared using a novel biocompatible and biodegradable poly(ester amide) based on the amino acid tyrosine, utilising a one-step interfacial polymerisation process. The produced tyrosine poly (ester amide) drug-loaded nanoparticles were evaluated for content uniformity, PSA, FTIR, TEM, DSC, XRD and aerodynamic performance (in vitro and in vivo). The optimised formulation demonstrated high entrapment efficiency– > 90%. The aerodynamic performance in terms of the emitted dose, fine particle fraction and respirable dose was superior to the carrier-based marketed product. In-vivo studies showed that FP (above the marketed formulation) and SAL reached the lungs of mice in a reproducible manner. These results highlight the superiority of novel FDC FP/SAL nanoparticles prepared via a one-step process, which can be used as a cost-effective and efficient method to alleviate the burden of asthma.

Fixed dose combinations (FDCs) incorporating two or three medicines in a single inhaler have been created to enhance patient compliance and hence clinical outcomes. However, the development of dry powder inhalers (DPIs), particularly for FDCs, faces challenges pertinent to formulation uniformity and reproducibility. Therefore, this project aimed to employ nanotechnology to develop a FDC of DPIs for market-leading medicines—fluticasone propionate (FP) and salmeterol xinafoate (SAL)—for asthma management. Nanoaggregates were prepared using a novel biocompatible and biodegradable poly(ester amide) based on the amino acid tyrosine, utilising a one-step interfacial polymerisation process. The produced tyrosine poly (ester amide) drug-loaded nanoparticles were evaluated for content uniformity, PSA, FTIR, TEM, DSC, XRD and aerodynamic performance (in vitro and in vivo). The optimised formulation demonstrated high entrapment efficiency– > 90%. The aerodynamic performance in terms of the emitted dose, fine particle fraction and respirable dose was superior to the carrier-based marketed product. In-vivo studies showed that FP (above the marketed formulation) and SAL reached the lungs of mice in a reproducible manner. These results highlight the superiority of novel FDC FP/SAL nanoparticles prepared via a one-step process, which can be used as a cost-effective and efficient method to alleviate the burden of asthma. [ABSTRACT FROM AUTHOR]

A series of aromatic polyesters were prepared by the reaction of bisphenol‐A and bis(hydroxyphenyl)butane with diacyl chloride monomers by phase transfer interfacial polycondensation in order to improve the processability of the bisphenol A‐based polyarylate. The microstructure, molecular weight, crystallinity, solubility, thermal properties, mechanical properties, and optical properties of the prepared copolyesters were investigated. Inherent viscosities of the copolyesters are in the range of 0.14–0.53 dl g−1, and their average molecular weights are 7362–44,413 g mol−1, respectively. The feed compositions and copolymer compositions were nearly identical. The results show that with the increase in the content of side ethyl units, the copolyester gradually transforms into an amorphous structure, which is also verified by the improvement in dissolution properties. When the copolyester backbone was introduced into the side ethyl units, the thermal decomposition temperature was less affected and varied in the range of about 10°C, while the value of glass transition temperature reduced from 196.5°C to 165.1°C. The mechanical properties of the polymers are similar to those of the industrial commodity U‐100. In addition, the copolyester films have good optical properties, and the transmittance reached the maximum value of 98.41% when the content of bis(hydroxyphenyl)‐butane was 10%. [ABSTRACT FROM AUTHOR]

Polymers based on the furanic compounds derived from renewable carbohydrates have seen massive growth due to their unique properties and increasing concerns about sustainability and environmental challenges. In this study, fully bio-based four new linear ion-exchange polyamides were synthesized by interfacial polymerization of bisfuran diamine monomer (BFN). The BFN monomer is prepared by condensing 2-aminomethyl furan with levulinic acid using an acid catalyst. The bisfuran polyamides are generally considered hydrophilic, with an observed swelling capacity range from 108 to 192%. The ion exchange capacity range was observed from 2.19 to 2.35. The thermal properties of the bisfuran polyamides were studied with differential scanning calorimetry and thermal gravimetric analysis. The glass transition values were ranged from 162.2 to 122.1 °C, and the 1% mass loss at temperatures was above 215 °C. An X-ray diffraction study proves amorphous nature with some degree of crystallinity at θ = 20°. [ABSTRACT FROM AUTHOR]

In this work, the synthesis of Nylon‐6.6 together with silver nanoparticles (presumably Ag2O, Ag NPs) was carried out at a polarized liquid‐liquid interface (LLI). The reduction of silver ions to Ag‐NPs was driven by an electrochemically controlled electron transfer reaction between silver cations initially dissolved in the aqueous phase and ferrocene species present in the organic phase. The formation of Ag2O is assumed to originate from Ag+ precipitation to AgOH further converted into Ag2O. The polyamide formation was derived from the interfacial polycondensation reaction happening between 1,6‐diaminohexane and adipoyl chloride. We studied the possibility to form given material simultaneously (interfacial polycondensation and Ag+ reduction occurring in one step) and sequentially (electrochemical Ag+ reduction by ferrocene from the organic phase was performed after polyamide deposition). The Ag‐based NPs‐polyamide material was synthesized at the macroscopic and microscopic LLI. As the support for the latter, fiberglass membranes was used. The resulting material was characterized by infra‐red (IR) spectroscopy and scanning electron microscopy (SEM). [ABSTRACT FROM AUTHOR]

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A series of polyarylates (PARs) containing pendent biphenyl moiety was synthesized via interfacial polycondensation polymerization from a mixture of three aromatic diols (4,4′-[1-(4-biphenylyl)ethylidene] bisphenol (BBP), 4,4′-[1-(4-biphenylyl)ethylidene]-bis,3-methyphenol (oBBP) and 4,4′-[1-(4-biphenylyl)ethylidene]bis,3,5-dimethylphenol (dmBBP)) with molar equivalent of terephthaloyl chloride (TC). The synthesized PARs (coded as BBP-TC, oBBP-TC, and dmBBP-TC) showed excellent thermal properties and solubility in common organic solvents as the incorporation of pendent biphenyl moiety. The inherent viscosity of PARs was in the range of 0.50–0.71 dl/g, while the number average molecular weights (Mn) were found in the range of 30,213–35,112 g/mol. All the PARs showed glass transition temperatures (Tgs) between 201 °C to 278 °C. The oBBP-TC observed low Tg as containing asymmetric dimethyl substitution, while other BBP-TC and dmBBP-TC were found normal Tgs due to symmetrical structure with and without methyl substitution. The 10 % weight loss degradation temperatures of PARs were found to be in the range of 395–423 °C. X-ray diffraction studies of polyesters showed that all the PARs were amorphous. The mechanical and optical properties of films were also analyzed to understand the desirability of PARs in further applicability. With regards to its solubility, thermal stability, mechanical properties, and optical properties, these PARs may be considered as a promising material in the field of processable high-performance engineering. [ABSTRACT FROM AUTHOR]

A three-phase junction formed between a solid electrode placed between solutions of the organic phase and the aqueous phase is employed for localized and electrochemically assisted nylon-6,6 deposition. The fluorine-doped tin oxide (FTO) conductive support (serving as the working electrode) is immersed into the cell filled with the aqueous solution of 1,6-hexanediamine (1,6-DAH) and the organic solution of adipoyl chloride (AC) dissolved in 1,2-dichloroethane. The interfacial polycondensation reaction between these two reagents occurs spontaneously at the liquid–liquid interface at elevated pH and is inhibited when diamine is fully protonated. With this in mind, we have designed a system where the pH close to the three-phase junction was increased using electrochemical water reduction triggering very localized polyamide deposition.

The interfacial polymerization of nylon-6,6 is studied at the polarized liquid–liquid interface. The optimal conditions (concentration of reagents in a biphasic system, pH of the water phase, voltammetric cycling) are used to modify the interface, supported by a microcapillary, giving a platform with molecular sieving properties.

• A new method for the kinetic study of interfactial hydrolysis of acid chlorides. • Conditions identified under which hydrolysis is important in interfacial polycondensation. • Technique based on pH fall during reaction, measured by a fast probe. • Hydrolysis is strongly pH dependent, and often self-limiting. • Hydrolysis kinetic modelled and the model validated. The interfacial hydrolysis of trimesolyl chloride (TMC) is studied in this work. TMC, together with meta -phenylene diamine (mPDA), forms the pair of monomers commercially used extensively in the preparation of thin film composite membranes for reverse osmosis. The interfacial hydrolysis of TMC is a side reaction in this process, and affects the kinetics of film formation and properties of the film that forms. Here, we develop a methodology for the kinetic study of this hydrolysis, and use it to determine and model the kinetics of hydrolysis of TMC. In order to provide the context, we first establish the circumstances under which it can be competitive with the main reaction. It is shown that pH has a significant effect on the kinetics of hydrolysis, and because of this, the hydrolysis can be self-limiting under most circumstances. The presence of a surfactant, often present in such systems, can influence the kinetics in significant ways. The kinetics has been modeled as a function of the reactant concentration and pH, and the model tested against experimental data obtained with different initial TMC concentrations, and at different concentrations of a commonly used surfactant, Tween 85. [ABSTRACT FROM AUTHOR]

• Polyamide films are formed at the electrified liquid-liquid interface. • Interfacial polycondensation reactions are assisted by ion transfer voltammetry. • Polyamide films block the transfer of tetramethylammonium cations. • Microscopic liquid-liquid interface brings stability to polymeric films. In this work, we present the possibility to electrochemically assist and study the interfacial polycondensation derived from the reactions between 1,6-diaminohexane or p- phenylenediamine (used as the diamine initially present in the aqueous phase) and acyl chlorides in a form of 1,3,5-benzenetricarbonyl trichloride, terephthaloyl chloride or adipoyl chloride (present in the organic phase – 1,2-dichloroethane solution). Polyamides are synthesized at the polarized liquid – liquid interfaces (or the interface between two immiscible electrolyte solutions – ITIES) as a consequence of the transfer of partly protonated diamines from the aqueous to the organic phase. In this respect, we have defined the aqueous phase pH assuring the availability of amine groups (-NH 2) for the reaction with the acyl chloride and protonated amine groups (-NH 3 +) defining the electrochemical interfacial activity of chosen compounds. The possibility to electrochemically assist the interfacial formation of polyamides was first tested using the macroscopic ITIES. Formed polyamides were collected and analysed using scanning electron microscopy, energy dispersive x-ray spectroscopy and Raman spectroscopy. Next, we have employed the microscopic ITIES (microITIES) based system formed using fused silica microcapillaries. Cyclic voltammetry was employed for the polyamide modified microITIES assessment (evolution of molecular sieving properties using a model ion - tetramethylammonium cation). [Display omitted] [ABSTRACT FROM AUTHOR]

The thickness and structure of microcapsule shell is the most important factor affecting essential performance of microcapsule. The growth of microcapsule shell prepared by interfacial polycondensation is self-limited which produces thin microcapsule shells with low mechanical strength. In this study, solvent dynamic swelling is employed to overcome the self-limitation of microcapsule shell prepared by interfacial polycondensation. It was found that the solvent dynamic swelling can enhance polyurethane shell and epoxy shell growth, and so that different shell structures could be regulated and the thickness of the shell could be increased. Finally, capsaicin microcapsules were prepared using epoxy resin as microcapsule shell, and capsaicin microcapsules with different core-shell structures were obtained by solvent regulation. The embedded microcapsule structure had lower release rate. The general effect of solvent evaporation and swelling on the interfacial polymerized microcapsule shell was explained, which provided a new paradigm for interfacial polymerized microcapsule shell structure regulation, especially the regulation of shell thickness. [Display omitted] • The self-limitation of interfacial polycondensation is overcome by solvent swelling and evaporation to extend reaction time. • The shell thickness of microcapsule by interfacial polymerization is greatly increased without self-limitation of interfacial polycondensation. • The release rate of encapsulated capsaicin in microcapsules with thick shell is prolonged. [ABSTRACT FROM AUTHOR]

Poly(urea-urethane) and polyurea microcapsules were prepared by an interfacial polymerisation using orange oil as a core material and a mixture of polymeric 4,4-methylenediphenyldiisocyanate and toluene diisocyanate in a molar ratio of 1:0.2 as oil-soluble monomers. The membrane composition, its thickness and other properties were varied by changing the type and amount of oil-soluble monomers and water-soluble chain extenders, such as ethylenediamine and diethylenetriamine based on amine groups and 1,4-butanediol and polyethylene glycol 400 based on hydroxyl groups. Studies of the morphology and release behaviour of microcapsules show high dependency on the reaction conditions and reactants’ properties. The release rate of the orange oil from microcapsules is highest when using a polymeric linear chain extender, polyethylene glycol with a molecular mass of 400. Improved mechanical stability and a slower release rate of microcapsules were achieved by a thicker membrane and by using the branched multi-functional chain extender diethylenetriamine.

Organotin polyesters were synthesized from d-camphoric acid. Since d-camphoric acid is a natural product, this is part of the green chemistry initiative. Further, synthesis occurred employing commercially available reactants and the interfacial system which is used industrially to synthesize aramids and polycarbonates. Thus, scale-up is straightforward. Polymers were synthesized employing the interfacial reaction between various organotin dihalides and the salt of d-camphoric acid. Reaction was rapid occurring in 30 s and less. Product yield was good except for the product from dioctyltin dichloride. The products are polymeric with chain lengths from 230 to 2200. Structural characterization with infrared spectrometry and MALDI MS are consistent with the formation of organotin polyesters containing the camphoric acid moiety within its backbone. IR shows formation of the Sn-OOC(O) linkage with the polymer having a combination of bridging and non-bridging geometrical arrangements about the tin atom. MALDI MS shows ion fragment to two and three repeat units. The products exhibit good ability to inhibit a battery of cancer cells including those from pancreatic cancer. The effective concentration for inhibition of the cancer cell lines are generally in the same range as those found for cisplatin and in the ng/mL range. [ABSTRACT FROM AUTHOR]

A series of new aromatic polyesters containing a (4-phenoxyphenyl)phenylmethene linkage were prepared by phase transfer-catalyzed interfacial polycondensation of 1,1-bis(4-hydroxyphenyl)-1-(4-phenoxyphenyl)-1-phenylmethane with terephthaloyl chloride, isophthaloyl chloride, and so on. The inherent viscosities of the polyesters ranged from 0.62 to 0.90 dL/g, while number-average molecular weights were in the range of 30,500–35,500 g/mol. All the polyarylates were readily soluble in organic solvents such as dichloromethane, chloroform (CDCl3), tetrahydrofuran, meta-cresol, pyridine, N,N-dimethylformamide, N,N-dimethylacetamide, and 1-methyl-2-pyrrolidinone at room temperature, and could be cast into tough, transparent, and flexible films from their CDCl3 solutions. Wide-angle X-ray diffraction measurements revealed the amorphous nature of the polyarylates. These polymers showed glass transition temperatures (Tgs) between 178°C and 240°C and decomposition temperatures at 10% weight loss ranging from 446°C to 483°C, while the initial degradation temperatures in the range of 410–435°C under nitrogen atmosphere. These new polyarylates exhibited higher Tgs and better solubility than bisphenol A-based analogues. [ABSTRACT FROM AUTHOR]

The structure and function of the thin polymeric functional layer in reverse osmosis membranes depend on the kinetics of the interfacial polycondensation (IP) reaction by which the film is formed. It has been a challenge to achieve a quantitative understanding of these kinetics because of the high velocity of the reactions and the complex geometry of the support membrane in which the reaction takes place. In this work, we describe a novel and convenient technique for studying such kinetics, and demonstrate the method on the IP reaction between meta -phenylene diamine and trimesoyl chloride. The method involves studying the reaction in a simple geometry of a drop-continuous phase interface in an emulsion, under such conditions that all transport resistances are eliminated. The reaction course is followed through an on-line pH measurement using a fast probe. Interfacial areas available for reaction are measured by an encapsulation technique, under the conditions of reaction. The methods developed have been used to study the kinetics of the m -PDA-TMC reaction as a function of m -PDA concentration and surfactant (tween-85) concentration, and a surface-area based rate function has been shown to fit the data adequately. [ABSTRACT FROM AUTHOR]

Water-soluble metallocene and organotin-containing polyethers were synthesized employing interfacial polycondensation. The reaction involved various chain lengths of poly(ethylene glycol), and produced water-soluble polymers in decent yield. Commercially available reactants were used to allow for easy scale up. The polymers exhibited a decent ability to inhibit a range of cancer cell lines, including two pancreatic cancer cell lines. This approach should allow the synthesis of a wide variety of other water-soluble polymers. [ABSTRACT FROM AUTHOR]

Our aim was to investigate the synthesis of alternative bio-based microcapsules, offering similar thermal and mechanical properties as formaldehyde-based ones and being directly applicable to the textile field. In this prospect, oligoamide microcapsules were generated by interfacial polycondensation from two bio-based monomers: succinyl chloride and 1,4-butanediamine. Optimization of the process afforded the preparation of monodispersed microcapsules with a d(0.5) diameter of 3 μm, exhibiting excellent stability over time. The expected amide groups in the microcapsules membrane were confirmed by FTIR, whereas SEC analysis suggested that microcapsules membrane was composed of oligoamide 4,4 chains with a D P ¯ n around 5. The chemical structure of model plane membranes prepared by interfacial polycondensation with jojoba oil as organic phase, was investigated by 13 C NMR and MALDI-TOF. The plane membranes appeared composed of PA 4,4 oligomers, in accordance with the information provided by SEC. The microcapsules exhibited a thermal degradation occurring in the range 200–350 °C, and a large melting endotherm peak centred on 200 °C. Thanks to the accurate thermal and mechanical properties of oligoamide 4,4, those microcapsules loaded with jojoba oil were successfully applied on cotton and polyamide fabrics which were submitted to laundering and rubbing tests. [ABSTRACT FROM AUTHOR]

In the present study, we synthesized water-soluble poly(ethylene glycol) methyl ether acrylate (PEGA)-containing polysulfide polymers by conventional interfacial polycondensation polymerization. Formation of polysulfide polymers was confirmed using gel permeation chromatography, FT-IR, and NMR spectroscopy. Thermal behaviors of polysulfide polymers were investigated by thermogravimetric analysis and differential scanning calorimetry. Degradation products of the main chain polysulfide polymers were characterized by electron-impact mass spectroscopy. These polysulfide polymers are soluble not only in most of the common organic solvents but also in water, though they contain highly hydrophobic -S x - (x = 1 or 2) moieties in the main chain. In addition, the synthesized PEGA-containing disulfide polymer was employed to stabilize gold nanoparticles in an aqueous medium to prevent self-aggregation. [ABSTRACT FROM AUTHOR]

Poly(ethylene tetrasulfide) (PSP) is synthesized via interfacial polycondensation of 1,2 dichloroethane and sodium tetrasulfide, in the presence of graphene oxide (GO). This process resulted in homogeneously dispersed PSP/GO nanocomposites. Nanocomposites of 0.3 and 0.5 wt% of GO are synthesized and their morphology, chemical characteristics behavior are studied employing field emission scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction techniques. Thermal characterization of composites is performed by differential scanning calorimetry and thermogravimetry analysis. Results indicate that the addition of only small amounts (0.5 wt%) of well-dispersed GO can increase the melting point more than 16°C resulting in better thermal properties for the composite. The solubility of nanocomposite is also studied and results show that the solubility depends on solvent concentration in addition to reinforcement (GO) deals. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) for heat energy storage have received an extensive attention in recent years. For heat energy storage application, a new type of polyurea (PU) microencapsulated phase change materials (MicroPCMs) were prepared by interfacial polycondensation method with isophorone diisocyanate (IPDI) and ethylene diamine (EDA) as shell monomers and paraffin as core material. The influences of monomer mass ratio, emulsifier type, emulsifier dosage and emulsifying stirring speed on MicroPCMs were investigated systemically. The morphology, chemical composition and particle size distribution of the MicroPCMs were characterized by using scanning electron microscope (SEM), fourier transform infrared (FT-IR) spectrum and laser particle size analyzer respectively. The results show that the MicroPCMs prepared under the optimal conditions have spherical shape and an average diameter of 2.42 μm. The results of differential scanning calorimeter (DSC) analysis show that the phase latent heat of the MicroPCMs is 92.5 J/g with 44.5% core content. The results of anti-osmosis test confirm that the MicroPCMs with the core/shell ratio of 75/25 have good compactness and stability. The microencapsulation technology developed is expected to be used in air conditioning, heating and other fields. [ABSTRACT FROM AUTHOR]

It was tried to form Pickering emulsion by use of paraffin wax as a phase change material (PCM) and SiC as solid powder and to apply to the preparation of the hybrid microcapsules with the interfacial polycondensation reaction. Pickering emulsion could be formed by stirring PCM and SiC in the continuous water phase. The mean diameter of PCM droplets in the (O/W) emulsion decreased with the added amount of SiC. The SiC weight adhered on the surface of PCM droplets become the maximum in the continuous phase with pH 6.8. The hybrid microcapsules with the shell made of SiC and polyurea resin film could be prepared by using Pickering emulsion. There was a critical adhesion weight of SiC, above which the hybrid microcapsules could not be formed. Thermal conductivity of hybrid microcapsules could be improved as compared with the PCM microcapsules. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A wide variety of organotin polyethers derived from the interfacial polymerization of dibutyltin dichloride and non-cancer inhibitory diols show decent to good inhibition of two human pancreatic cancer cell lines. In view of the general lack of ability of tested compounds to inhibit pancreatic cancer cell lines, this is significant. These cell lines are the AsPC-1 pancreatic cancer cell line which is an adenocarcinoma pancreatic cell line and the PANC-1 pancreatic cancer cell line which is an epithelioid carcinoma pancreatic cell line. The dibutyltin polyethers generally both exhibit EC50values in the same range and lower than cisplatin and higher CI50values than cisplatin. Essentially all of the polymers derived from simple non-aromatic diols showed CI50values greater than 2. [ABSTRACT FROM PUBLISHER]

Polyphosphonates of high molecular weights were prepared from chloromethylphosphonic dichloride (CMPD) and 4,4’-sulfonyldiphenol (SDP) by two-phase interfacial polycondensation (l–l), in an organic solvent-aqueous alkaline solution system, with a phase-transfer catalyst, at –8 º – 0 ºC. Alternative method, namely vapor-liquid interfacial polycondensation (v–l) of the same reagents gave better results (higher inherent viscosities and molecular weights). The polymers were characterized by spectroscopic techniques IR and 1H-NMR. The molecular weights and thermal stability determinations were carried out by gel chromatography and thermogravimetry. The effect of reaction temperature on yield and inherent viscosity in l–l and v–l interfacial polycondensation was studied. In l–l system the highest inherent viscosities were obtained at –8 º – 0 ºC, whereas in v–l system the maximum inherent viscosity was obtained at 120 ºC.

Polyphosphonates of high molecular weights were prepared from chloromethylphosphonic dichloride (CMPD) and 4,4’-sulfonyldiphenol (SDP) by two-phase interfacial polycondensation (l–l), in an organic solvent-aqueous alkaline solution system, with a phase-transfer catalyst, at –8 º – 0 ºC. Alternative method, namely vapor-liquid interfacial polycondensation (v–l) of the same reagents gave better results (higher inherent viscosities and molecular weights). The polymers were characterized by spectroscopic techniques IR and 1H-NMR. The molecular weights and thermal stability determinations were carried out by gel chromatography and thermogravimetry. The effect of reaction temperature on yield and inherent viscosity in l–l and v–l interfacial polycondensation was studied. In l–l system the highest inherent viscosities were obtained at –8 º – 0 ºC, whereas in v–l system the maximum inherent viscosity was obtained at 120 ºC.

[Display omitted] • Large-sized polymethylsilsesquioxane spheres were prepared by microdroplet method. • A step T -junction microchannel was used to generate monodispersed microdroplets. • The microdroplets were solidified via rapid in-situ interfacial polycondensation. • Corrugated/smooth surface and loose/dense internal structure could be obtained. • Particle size could be tuned from tens of microns (∼20 μm) to hundreds of microns. Monodispersed polysilsesquioxane (PSQ) microspheres are generally synthesized by the classical sol–gel method. Using this method, the particle size is limited to the range of several hundred nanometers to several microns. The preparation of monodispersed large-sized PSQ microspheres remains technically challenging. Herein, with the polymethylsilsesquioxane (PMSQ) microspheres as the model product, a microdroplet-based strategy was developed for the synthesis of PSQ microspheres with larger particle sizes. According to the properties of the reactants, a W/O microdroplet reaction system was realized, i.e., with the mixture of methyltrimethoxysilane (MTMS) and liquid paraffin as the continuous phase and ammonia solution as the dispersed phase. The monodispersed W/O microdroplets were generated in a step T -junction microfluidic device, and solidified into PMSQ microspheres via in-situ interfacial polycondensation (∼2 min) in a microtube reactor. The size, surface morphology and internal structure of the PMSQ microspheres could be tuned by adjusting the synthesis conditions, mainly including the two-phase flow rates, MTMS concentration, NH 4 OH concentration, and the structural parameters of the microfluidic device. Various PMSQ microspheres with corrugated or smooth surface morphology, and loose or dense internal structure could be synthesized. The microsphere size could be tuned from tens of microns (∼20 μm) to hundreds of microns. [ABSTRACT FROM AUTHOR]

Organotin polyamine ethers containing thiamine (Vitamin B) were synthesized employing the interfacial polymerization of thiamine and organotin dichlorides. Reaction is rapid occurring in less than 15 s in moderate to poor yield with chain length ranging from 86 to 860 units. Infrared spectroscopy shows new bands characteristic of the formation of the Sn-N and Sn-O linkages. Proton NMR shows the presence of both the organotin and thiamine moieties. MALDI MS results shows ion fragment clusters to three units with ion abundance results consistent with the presence of tin atoms within the ion fragment clusters. The polymers all exhibit inhibition of the cancer cell lines including two breast, two pancreatic, prostate, and colon cancer cell lines at levels better than those for the standard cisplatin, one of the most widely employed anticancer drugs. [ABSTRACT FROM AUTHOR]

Organotin polyesters were synthesized in good to poor yield with yield and chain length generally decreasing as the alkyl chain on the organotin increases. MALDI MS, NMR, and IR data is consistent with the proposed repeat unit. MALDI MS ion fragment clusters to four repeat units are found. The IR shows the presence of a new band assigned to the formation of the Sn-O. With the exception of the dimethyltin polymer, all of the polymers exhibit good inhibition of a variety of cancer cell lines including two breast cancer, prostate, two pancreatic cancer and colon cancer cell lines. [ABSTRACT FROM AUTHOR]

Poly(urea-urethane) and polyurea microcapsules were prepared by an interfacial polymerisation using orange oil as a core material and a mixture of polymeric 4,4'-methylene diphenyl diisocyanate and toluene diisocyanate in a molar ratio of 1:0.2 as oil-soluble monomers. The membrane composition, thickness, and other properties were varied by changing the type and amount of oil-soluble monomers and water-soluble chain extenders, such as ethylenediamine and diethylenetriamine based on amine groups and 1,4-butanediol and polyethylene glycol 400 based on hydroxyl groups. Studies of the morphology and release behaviour show high dependency on the reaction conditions and reactants' properties. The release rate of the orange oil from microcapsules is highest when using a polymeric linear chain extender, polyethylene glycol with a molecular mass of 400. Microcapsules with improved mechanical stability and a slower release rate were obtained by a thicker membrane and by using the branched multi-functional chain extender diethylenetriamine. [ABSTRACT FROM AUTHOR]

A series of thermotropic liquid crystalline polyesters derived from bis-(4-hydroxybenzoyloxy)-2- methyl-1,4-benzene (BHBOMB) and aliphatic dicarboxylic acid chlorides were investigated. All these polyesters were synthesized by interfacial polycondensation method and characterized by differential scanning calorimetry and wide-angle X-ray diffractometer. These polyesters consist of BHBOMB as a mesogenic diol and aliphatic diacid chlorides were used as flexible spacers. The length of oligomethylene units in polymer was varied from the trimethylene to the dodecamethylene groups. The transition temperatures and thermodynamic properties were studied for all these polymers. All these polyesters were soluble in chlorinated solvents such as chloroform, dichloromethane, dichloroethane, etc. More importantly, all these polyesters exhibited very large mesophase stability. [ABSTRACT FROM AUTHOR]

The efforts described in this article are aimed at designing organotin polymers that control the growth of breast cancer and to identify structure/property relationships that assist in this goal. The growth of MCF-7 and MDA-MB-231 breast cancer cell lines is inhibited employing a wide range of organotin condensation polymers. The EC50values are primarily dependent on the nature of the Lewis base but the CI50is dependent on both the nature of the Lewis base and Lewis acid. A number of products exhibit CI50values greater than two including a number of organotin polyethers such as those derived from diethylstilbestrol, dienestrol, short-chained dibutyltin polyethers, and hydroquinone derivatives. In most of these cases the MDA-MB-231 cells exhibit greater inhibition compared to the estrogen receptor (ER) MCF-7 cells. The organotin polymers generally exhibit a superior ability to inhibit MCF-7 and MDA-MB-231 breast cell growth compared to the standard cisplatin. [ABSTRACT FROM PUBLISHER]

The current efforts described in this paper are aimed at developing compounds that inhibit the growth of prostate cancer and to identify structure/property relationships that will further assist us towards this goal. The growth of prostate cancer is affected employing a wide range of organotin condensation polymers. The EC values are primarily dependant on the nature of the Lewis base but the CI is dependent on both the nature of the Lewis base and Lewis acid. EC values down to the picogram/mL range are found. A number of products exhibit CI values greater than two. For polymers derived from hydroquinone and hydroquinone derivatives ability to inhibit cancer cell growth decreases as the bulk of substituents increases. [ABSTRACT FROM AUTHOR]

Here, we report the first synthesis of water soluble poly( N -isopropylacrylamide- co - N , N ′-dimethylacrylamide sulfide) copolymers via conventional interfacial polycondensation method using phase transfer catalyst (PTC). The effect of various kinds of PTC having different aliphatic chain length and counter ion were employed to examine the kinetics of polysulfide polymer formation. The reactivity ratios, determined employing extended Kelene–Tüdös method using feed composition obtained from 1 H NMR analysis, suggest that N -isopropylacrylamide (NIPAM) is more reactive than N , N ′-dimethylacrylamide (DMA) in both mono- and di-sulfide polymers. Thermal transition behavior investigated by differential scanning calorimetry (DSC) demonstrated that as the sulphur rank of the sulfide main chain linkages increased, the flexibility of the polymers increased reflected by lower glass transition temperature ( T g ) values. The thermal degradation behavior and the major degradation products have been characterized by thermogravimetric analysis (TGA) and electron-impact mass spectroscopy (EI-MS), respectively. Both the studies reveal that the degradation takes place due to weak-link scission of the polymeric main chain. Solubility in water and in most of the common organic solvents even after the sulphur rank increased from 1 to 2 in the main chain, is expected to render potential applications in biological field as well as in industry for these interesting new class of polymers. [ABSTRACT FROM AUTHOR]

The interfacial condensation between the salt of thiodiglycolic acid and the Group V dihalides produces the corresponding polyesters in moderate to good yield in 15 secs and less. The products are tacky to glassy. Infrared spectroscopy shows the formation of the M-O linkage with bands present derived from both reactants. The geometry about the metal is predominately non-bridging. MALDI MS shows ion fragment clusters to two repeat units with ion fragment clusters consistent with the formation of the M-O-C(O)- linkage. The arsenic polymer exhibits outstanding inhibition of the AsPC-1 adenocarcinoma pancreatic cancer cell line. Both the arsenic and antimony polymer show good inhibition of the PC-3 prostate cancer cell line. The antimony polymer shows good inhibition of both the MDA-MB-231 breast cancer cells that are estrogen-independent and estrogen receptor negative and the MCF-7 breast cancer cells that are an estrogen receptor (ER) positive cancer cell line. [ABSTRACT FROM PUBLISHER]

Organotin polyesters were synthesized from the interfacial condensation of organotin dihalides and salts of 3,5-pyridinedicarboxylic acid. The polymers are synthesized in moderate to high yields and are moderate to high polymers. MALDI MS, IR spectral, and NMR spectral results are consistent with the proposed structure. The Sn-O stretching band is found at about 1,028 cm. Infrared spectra are consistent with majority of the products having a non-bridged structure about the tin. All of the polymers exhibit some inhibition of two pancreatic cancer cell lines. The dibutyltin and dicyclohexyltin products show sufficiently good inhibition of both cell lines as to merit further testing. [ABSTRACT FROM AUTHOR]

A series of homo and copolyphosphonate derivatives were synthesized by interfacial polycondensation reactions of 1,3-bis(4-hydroxyphenyl)propenone with phenylphosphonic dichloride and terephthaloyl chloride, and 3-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)propenone with phenylphosphonic dichloride and terephthaloyl chloride using a phase transfer catalyst at ambient temperature. The diol monomers were prepared by condensing 4-hydroxy benzaldehyde and 3-methoxy-4-hydroxybenzaldehyde with 4-hydroxy acetophenone. The structures of the synthesized monomers and polymers were confirmed using UV, IR and H, C, and P NMR spectroscopic techniques. The molecular weights of the polymers were determined by gel permeation chromatography. The thermal properties of the polymers were studied by thermogravimetric analysis and differential scanning calorimetry under a nitrogen atmosphere. The photosensitive property of the polymers in films and solution states was investigated by ultraviolet spectroscopy. Photocrosslinking proceeded via a 2 π+2 π cycloaddition reaction of α,β-unsaturated carbonyl group. The chemical and physical properties of methoxy substituted polymers were compared to those of the unsubstituted polymers. The structure-property relationships and flame retardant characteristics of the synthesized polymers were also studied. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Novel biodegradable and low cytotoxic poly(ester amide)s (PEAs) based on α-amino acids and (L)-lactic acid (L-LA) oligomers were successfully synthesized by interfacial polymeri-zation. The chemical structure of the new polymers was confirmed by spectroscopic analyses. Further characterization suggests that the α-amino acid plays a critical role on the final properties of the PEA. L-phenylalanine provides PEAs with higher glass transition temperature, whereas glycine enhances the crystallinity. The hydrolytic degradation in PBS (pH = 7.4) at 37 °C also depends on the α-amino acid, being faster for glycine-based PEAs. The cytotoxic profiles using fibroblast human cells indicate that the PEAs did not elicit an acute cytotoxic effect. The strategy presented in this work opens the possibility of synthe-sizing biodegradable PEAs with low citotoxicity by an easy and fast method. It is worth to mention also that the properties of these materials can be fine-tuned only by changing the α-amino acid. [ABSTRACT FROM AUTHOR]

Abstract: In this study, Taguchi’s method was implemented to evaluate and to optimize the experimental conditions for the preparation of polyurea and polyurethane nanoparticles using emulsion–diffusion process. The effects of the hydrophilic monomer choice (1,4-diaminobutane (BDA) or 1,4-butanediol (BDO)), the concentration of surfactant (Tween 20), the concentration of dispersant (Sodium Dodecyl Sulfate, SDS), the organic solvent volume ratio (acetone/ethyl acetate), the time of addition of SDS and the time of dilution were studied on the encapsulation yield and efficiency, and particle size distribution. Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were performed to characterize the chemical structure and the thermal stability of these nanoparticles. The statistical analysis revealed that the most important factors contributing to the encapsulation efficiency are percent of surfactant, acetone content, selection of hydrophilic monomer, and dilution time. Moreover, the monomer choice influences the size distribution mode as well as the mean diameter. In most of cases unimodal distribution with a mean diameter between 125 and 1083nm were obtained when BDA was used as hydrophilic monomer. [Copyright &y& Elsevier]