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A series of new polyarylates bearing cardo xanthene groups were synthesized by phase-transfer-catalyzed interfacial polycondensation of 9,9-bis[4-(4-chloroformylphenoxy)phenyl]xanthene with various bisphenols containing the isopropylidene, hexafluoroisopropylidene, 1-phenylethylidene, diphenylmethane, cyclohexane, and xanthene structures. High-molecular-weight polyarylates with number-average molecular weight and polydispersity index in the range of 30,100–35,300 and 1.82–2.17, respectively, exhibited high glass transition temperatures ranged from 226°C to 261°C, and their 10% weight loss temperatures were in the range of 421–452°C with char yields above 45% at 700°C in nitrogen. All the polyarylates were amorphous and readily soluble in organic solvents such as dichloromethane, chloroform, 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 with tensile strengths of 85.6–108.3 MPa, elongations at break of 2–3%, and tensile moduli of 7–9 GPa.

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. (C) 2017 Elsevier Ltd. All rights reserved.

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 EC50 values are primarily dependant on the nature of the Lewis base but the CI50 is dependent on both the nature of the Lewis base and Lewis acid. EC50 values down to the picogram/mL range are found. A number of products exhibit CI50 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.

The application of microencapsulated liquid gasifiable fire-extinguishing agents as reactive filling compounds for fire-extinguishing composites is considered. A new process for microencapsulation of environmentally friendly fire-extinguishing agents possessing enhanced stability is designed. Novel composite materials are produced with these agents. The thermal-destruction processes of microcapsules containing liquid gasifiable fire-extinguishing agents of different compositions are considered. Laboratory and bench-mark firing tests of the materials are performed.

Interfacial polycondensation, with its multiphase character and the involvement of several rate and equilibrium processes, presents unique challenges to our ability to understand and design processes for achieving desired properties. In a recent study [1] , we have presented a detailed model for the process and shown that it explains the salient features as reported in the literature for several interfacial systems. In the present paper, we report extensive experimental studies on the polyurea system and their comparison with the model. Two geometries – the spherical geometry of the microcapsule and the flat-film geometry – have been used to study qualitative and quantitative features of the polycondensation and the nature of the film that forms. While some aspects, such as the manner in which the solvent influences the kinetics, confirm earlier findings, inadequacies have been identified in the sample preparation protocols followed in earlier work, because of which property estimations may carry a large error. Improved protocols have accordingly been developed and used to study the development of film properties in time and as a function of the important preparation variables. Detailed molecular weight distributions have been determined using a GPC technique and used to derive important properties of the polyurea (such as Mark–Houwink parameters) as well as to gain insights into mechanisms. The data have been used to determine the rate parameters in the Dhumal and Suresh [1] model. The predictions of the model, as far as trends are concerned, are shown to be satisfactory given the level of uncertainty about parameter values and the complexity of the system being studied. Where discrepancies exist, the reasons have been established and the areas for improvement of the model identified. The findings reported are of interest to applications such as controlled release and membrane separations, in which permeation rate through the membrane is of importance and depends upon various membrane properties like crystallinity, morphology, etc.

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.

Interfacial polycondensation of cyclohexanedicarbonyl dichlorides and adamantanedicarbonyl dichloride with bisphenols in 2M NaOH aq./CHCl 3 afforded semi-aromatic polyesters. Glass transition temperatures (T g 's) of the resulting polyesters are in the range of 110-222 °C. Temperatures where 5% weight losses of the polyesters occur in N 2 are in the range of 304-448°C. Polyesters 4 and 10, which include trans-1,2-cyclohexanediyl and 1,3-adamantanadicarbonyl units, respectively, have excellent solubility in organic solvents. The polyester films 10a,b,e, which are prepared by casting from CHCl 3 , have excellent transparency.

Organotin polyesters have been synthesized employing the classical interfacial polycondensation of organotin dihalides and the salt of 1,1′-ferrocenedicarboxylic acid. The products are oligomeric (DP = 5) to polymeric (DP = 220). The presence of new IR bands characteristic of formation of the Sn–O band are present. Ion fragments characteristic of the repeat unit and greater are found employing F MALDI MS.

The works on mathematical modeling of interfacial polycondensation are reviewed over the period since 1970s up to now. Attention is primarily paid to the techniques of local and macrokinetic modeling. Two approaches to the theoretical description of polycondensation have been formed up to date. The first one is based on analytical or semianalytical solution of differential balance equations using the stationary mass transfer approximation. The second one consists in numerical solu- tion of the system of reaction-diffusion equations for the diffusion boundary layer of the reaction phase. The advantages and drawbacks of these approaches, specific fea- tures of their realization, basic results, as well as ways of combining these methods are discussed. A possibility of building a general model of interfacial polycondensa- tion as a hierarchical combination of kinetic, local, and macrokinetic models is shown.

Several polyarylates were synthesized from the interfacial or high-temperature solution polycondensation reactions of four bisphenols including 2,2-bis(4-hydroxyphenyl)propane (BPA), 2,2-bis(4-hydroxyphenyl)hexafluoropropane (BPAF), 1,1-bis(4-hydroxyphenyl)-1-phenylethane (BPAP), and 1,1-bis(4-hydroxyphenyl)-1-phenyl-2,2,2-trifluoroethane (BPAPF) with various aromatic diacyl chlorides. The basic properties such as inherent viscosity, film-forming capability, crystallinity, and mechanical and thermal properties and the “structure-property” relationships of these polyarylates were investigated. The polyarylates derived from asymmetric BPAP and BPAPF had lower crystallinity and higher solubility and glass-transition temperature (Tg) than the corresponding counterparts based on symmetric BPA and BPAPF. The fluorinated polyarylates revealed higher Tg values and decomposition temperatures than the corresponding nonfluorinated polyarylates.

Linear [m,n]-type polyurethanes (PUs) fully based on renewable materials are synthesized by interfacial polycondensation reaction of diamines derived from the amino-acid cystine with (bis)chloroformates derived from alditols having L-arabino or xylo configuration. The degradability of the new PUs has been enhanced by the introduction of disulfide linkages into the polymer backbone leading to a new group of stimulus-responsive sugar-based polyurethanes able to be degraded by glutathione under physiological conditions. All these polyurethanes are stable up to around 245°C, decomposing at higher temperatures through a one-stage mechanism. The new materials display high chemical homogeneity and degradability in both hydrolytic and reductive environments, with reductions of above 90% in Mw. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41304.

Polyesters based on a difuranic diacid chloride and various aliphatic diols or bisphenols were prepared by solution and interfacial polycondensation. The latter procedure gave, after optimization, materials with much higher molecular weights. These polymers were characterized in terms of both structure and thermal properties.

Pseudopolyrotaxanes and polyrotaxanes of polyamide and the macrocycle cucurbituril are synthesized easily by interfacial polycondensation. With different diammonium ions and diacid chlorides a great variety of poly(amide rotaxane)s is obtained. The structure of the diacid chloride influences the possible motion of cucurbituril on the polymer chain. First attempts to characterize these polyrotaxanes using IR, DTA, 1 H-NMR and elemental analyses are reported.

Several polyarylates based on UV sensitive bisbenzylidenoketones for use as potential second-order nonlinear optical (NLO) materials have been obtained by interfacial polycondensation. The polymers investigated can be divided into two groups: guest-host systems and polyarylates with NLO side-chains. The electro-optic (EO) coefficient, r 33 , was measured in the Pockels experiment. UV crosslinking was applied to increase NLO stability of the investigated materials. Loss and time relaxation of EO coefficient for crosslinked and noncrosslinked polyarylates were also measured.

The glycolysis of poly (ethylene-terephthalate) with bisphenol-A at certain ratios of PET/BPA was carried out in an autoclave reactor at different temperatures for varying periods of time. Then the glycolyzed products were utilized together with bisphenol-A for the synthesis of polyarylates through interfacial polycondensation. The polyarylates obtained (referred to as b/g-polyarylates in this article) possess good thermal characteristics but have lower mechanical strength than typical polyarylate synthesized from pure bisphenol-A by use of the same method. Blending the b/g-polyarylate with polycarbonate improved the impact strength significantly. As a whole, glycolysis with bisphenol-A followed by synthesis of polyarylate through interfacial polycondensation provided a feasible route for the reuse of poly(ethylene terephthalate).

The synthesis is described of some aromatic polyamides based on unsubstituted, and methyl-, carboxy-, and sulfo-substituted diamines by interfacial polycondensation. Some of them are crosslinked and some of them contain heterocyclic aromatic rings. Their chemical structures are characterized by IR and C-13 solid-state NMR spectra and the spectra are interpreted. (C) 1996 John Wiley & Sons, Inc.

Interfacial polycondensation is a rapid, irreversible polymerization at the interface between water containing one difunctional intermediate and an inert immiscible organic solvent containing a complementary difunctional reactant. It is based on the Schotten-Baumann reaction in which acid chlorides are reacted with compounds containing active hydrogen atoms (—OH, —NH and —SH). A large number of polymers (heat-sensitive and infusible as well as stable and meltable) can be prepared. The method has been applied to the preparation of polyurethanes, polyamides, polyureas, polysulfonamides, and polyphenyl esters. Interfacial polycondensations are run in simple, open laboratory equipment with or without stirring. With suitable agitation granular or powdered polymers with high molecular weight are prepared at room temperature and isolated within a few minutes. The intermediates need not be absolutely pure or in balance nor is a quantitative yield needed in order to obtain high polymer. The major variables in the interfacial polycondensation process are discussed and the laboratory techniques and principles are contrasted with melt polycondensation.

Products with hydroxyl ends were synthesized from the esterification of bisphenol-A, terephthalic acid and ethylene glycol. These ester products were then used for synthesis of polyarylate by interfacial polycondensation. Not only the relative concentrations of reactants for esterification but also the conditions for interfacial polycondensation, such as the monomer ratio between two phases and the reaction time, play significant roles in affecting the properties of final products. Under proper synthesis conditions, the polyarylate formed could possess equivalent thermal characteristics and much higher impact strength in comparison with unmodified polyarylate due to the incorporation of flexible aliphatic segments from ethylene glycol. X-ray diffraction showed the existence of aliphatic segments would induce small degree of orderly alignment locally in structure.

New polythioesters were obtained by interfacial polycondensation of bis(4-mercaptophenyl)sulphone with some aliphatic and isomeric phthaloyl dichlorides. To determine optimal conditions of polycondensation, polythioesters from bis(4-mercaptophenyl)sulphone sebacoyl as well as isophthaloyl dichlorides were chosen as a model system. The structures of all polythioesters were determined by elemental analysis, i.r. and X-ray analysis. Initial decomposition temperature and maximum rate of decomposition temperature were defined from the curves of thermogravimetric analysis. Some physicochemical, mechanical and electrical properties have been determined.

The synthesis of of hydrophilic polyamides by polycondensation of 2,3,4,5-tetra-O-acetyl-galactaroyl dichloride with various heterocyclic carbohydrate-derived diamines and hexamethylene diamine. Polyamides with free hydroxy groups were obtained by removal of acetyl groups

3,5-Bis(p-hydroxybenylidene)-isopropylpiperidinone (BHIP) and 3,5-divanillylidene-isopropylpiperidinone (DVIP) were used as new starting materials for preparing new unsaturated polyesters. The polyesters were prepared by reacting BHIP or DVIP with adipoyl, sebacoyl, isophthaloyl or terephthaloyl dichlorides utilizing the interfacial polycondensation technique. In addition, the model compounds were synthesized by reacting BHIP or DVIP with benzoyl chloride. The model compounds were characterized by 'H-NMR, IR, and elemental analyses. The polyester samples have been characterized by elemental and spectral analyses. All the synthesized polymers readily dissolved at room temperature in dimethylsulphoxide or concentrated sulphuric acid. The thermal properties of the polymers were evaluated and correlated to their structural units by TGA measurements. X-ray analysis of the polymers showed that all the polyesters are amorphous.

A detailed model for interfacial polyconclensation (IP) reaction, which accounts for the salient equilibrium and rate processes in reaction and phase separation, is reported here. The modeling of nucleation phenomena is more rational and fundamentally based than so far attempted in the literature on this process. Simpler models are proposed for situations in which one of transport and reaction resistances is the dominant one, and criteria developed that guide the selection of the model. The model explains the empirical findings on different interfacial systems, which have been reported in the literature. An extensive parametric study has been carried out in order to explain the effect of the important dimensionless parameters that arise, and analysis shows that most of the effects observed can be rationalized with respect to certain types of asymptotic behavior. The model makes it possible to predict the time course of development of the important film properties such as thickness, MWD and crystallinity, and to relate these to the preparation conditions and system parameters, as embodied in the different dimensionless parameters. It should therefore be possible to use this model to choose synthesis conditions and system-dependent parameters to achieve desired properties. (C) 2009

The surface activity of aqueous solutions of melamine formaldehyde resins was investigated at different stages of the resin synthesis. Partially methanol etherigied melamine formaldehyde resins, which are able to form microcapsules, are reactive surface active compounds. The formation of capsuole walls with these resins proved to be a one-component interfacial polycondensation reaction. Die grenzflachenaktivita wasriger Losungen von Melamin-Formaldehyd-Harzen wurde in verschiedenen Stufen der Harzynthese untersucht. Zur Bildung von Mikrokapseln geeignete, partiell methanolveretherte Melamin-Form-aldehyd-Harze sind reaktionsfahige grenzflachenaktive Verbindungen. Die Bildung der Kapselwande aus diesen Verbindungen ist eine Einkomponenten-Grenzflachenpolykondensation.

Etude de la cinetique en variant le rapport molaire bisphenol A/chlorure d'isophtaloyle. Deduction de la forme integree de l'equation de vitesse pour des reactions non stœchiometriques a partir de l'equation R=d[B]/dt=K[B][I]. Bon accord entre les donnees de l'equation

Aqueous core/polymer shell microcapsules with mommuclear and polynuclear core morphologies have been formed by internal phase separation from water-in-oil emulsions. The water-in-oil emulsions were prepared with the shell polymer dissolved in the aqueous phase by adding a low boiling point cosolvent. Subsequent removal of this cosolvent (by evaporation) leads to phase separation of the polymer and, if the spreading conditions are correct, formation of a polymer shell encapsulating the aqueous core. Poly(tetrahydrofuran) (PTHF) shell/aqueous core microcapsules, with a single (mononuclear) core, have been prepared, but the low T-g (-84 degreesC) of PTHF makes characterization of the particles more difficult. Poly(methyl methacrylate) and poly(isobutyl methacrylate) have higher T-g values (105 and 55 degreesC, respectively) and can be dissolved in water at sufficiently high acetone concentrations, but evaporation of the acetone from the emulsion droplets in these cases mostly resulted in polynuclear capsules, that is, having cores with many very small water droplets contained within the polymer matrix. Microcapsules with fewer, larger aqueous droplets in the core could be produced by reducing the rate of evaporation of the acetone. A possible mechanism for the formation of these polynuclear cores is suggested. These microcapsules were prepared dispersed in an oil-continuous phase. They could, however, be successfully transferred to a water-continuous phase, using a simple centrifugation technique. In this way, microcapsules with aqueous cores, dispersed in an aqueous medium, could be made. It would appear that a real challenge with the water-core systems, compared to the previous oil-core systems, is to obtain the correct order of magnitude of the three interfacial tensions, between the polymer, the aqueous phase, and the continuous oil phase; these control the spreading conditions necessary to produce shells rather than "acorns".

Thermally curable polymers [C(=C[CN] 2 )PhC(=C[CN] 2 )] n [OPhC(Me) 2 PhO] n+m [COPhCO] m m/n= 1/0, 0/1, 4/1, 2/1, 1/1, 1/2, 1/4) with molecular weights M n in the 3900-4900 range are synthesized by interfacial polycondensation. The polymers with dicyanovinyl groups exhibited 10% weight loss temperatures of 428-491°C

A mechanistic study regarding the synthesis of aromatic polyimides (PIs) under hydrothermal conditions is presented. We demonstrate evidence that the first step of the reaction is the formation of a nylon type salt, which can be isolated. Upon heating the salt in the presence of water at 180 °C, polyimides are formed from the salts. Additionally performed DFT calculations substantiate the experimental findings and give evidence that the formation of imides is energetically favorable in hot water. The intermediate salts as well as the resulting PIs are characterized by diverse analytical techniques (SEC, FT-IR, WAXS, SEM). By selective fractionation, it is possible to obtain polyimides of moderate to high molecular weights that form tough films. The polymerization mechanism is discussed, and it is shown that different loci of reaction are possible, namely interfacial polycondensation, heterophase polymerization and topochemical transformations, which seem to occur in parallel. Finally, poloxamers can be used as additives for the fine-tuning of the polymer morphology.

Synthesis of Aromatic Polyesters by Interfacial Polycondensation Using Immiscible Binary Solvents

Six intrinsically coloured azo polyamides have been prepared by interfacial polycondensation and characterized by visible, ultra-violet and infra-red spectroscopy, viscometry and differential thermal analysis.

Polyesters of aromatic-cycloaliphatic type were synthesized by interfacial polycondensation from aromatic diols and C-3 and C-4 cycloaliphatic chloroanhydrides. The polymers were characterized by i.r. spectroscopy and thermogravimetry. Their thermal properties showed that these products range generally between fully aromatic and aliphaticaromatic polyesters. Aromatisch-cycloaliphatische Polyester wurden ausgehend von aromatischen Diolen und cycloaliphatischen C-3 und C-4 Chloranhydriden durch Phasengrenzenpolykondensation synthetisiert. Die Polymere wurden IR-spektroskopisch und thermogravimetrisch charakterisiert. Hinsichtlich des thermischen Verhaltens sind diese Produkte zwischen vollaromatischen und aliphatisch-aromatischen Polyestern einzureihen.

High molecular weight polyamide (PC-6) with macrocyclic polyetheral rings incorporated into the polymeric backbone was synthesized by a modified interfacial polycondensation of isophthaloyl chloride with diamino-dibenzo-18-crown-6. The high molecular weight polymer is a good film-forming material and forms homogeneous blends with poly(vinylpyrrolidone) (PVP). Scanning electron microscopy did not reveal any heterogeneity in such blends. The water-soluble PVP is not leached out from the blends even after a prolonged storage in water. Excellent mechanical properties of PC-6 were not adversely affected by blending it with PVP. The thermomechanical analysis and differential scanning calorimetry of the blends showed a single transition in lieu of those of the two components. PVP was also found to exert a stabilizing effect on the polyamide. The blends have been found to be thermally more stable than their components.

Transport properties of asymmetric copolymide membranes made by interfacial polycondensation were studied. The directional flow preference observed in diffusion experiments with ionic permeants can be explained by the swelling behavior of the membrane. As a consequence of the weak acidic and weak basic endgroups, the ion exchange characteristics of the membrane are a function of the pH value in the ambient solution and can be changed from cation to anion exchange properties. Like a bipolar double membrane, it is composed of an cationite and an anionite region. The current–voltage characteristics were found to be asymmetric.

Different polyamides and polysulfonamides were prepared by the interfacial polycondensation method. The influence of the experimental condition was specified. The principal characteristics of polymers are indicated (solubilities, molecular weights, IR spectra, thermal stability). In the case of poly(ethylene 1,3-benzenesulfonamide), a study of the thermal behavior was specially developed.

Potentiometric titrations and electrophoretic mobility measurements were made on carboxylated polyphthalamide microcapsules prepared by the interfacial polycondensation method. The values of surface potential and zeta potential of the microcapsules were calculated by using a theoretical potentiometric equation and the simple Smoluchowski equation, respectively. The ionic strength of the medium was found to have no effect on the conformation of the polymer chains of the microcapsules. The negative surface potential obtained from potentiometric titration data rose first with increasing pH of the medium and then tended to level off as the pH approached 7 while the zeta potential as evaluated from electrophoresis data was found to change until the pH attained a value of 10. The cause for this difference in pH change between the surface potential and the zeta potential of the microcapsules was ascribed to the reason that potentiometric titration does not permit the detection of terminal amino groups of the polymer chains constituting the microcapsules, which are far smaller in number than the carboxyl groups, while electrophoresis can detect the presence of the terminal amino groups.

Results are presented for pilot plant scale experiments on the preparation of polycarbonates. Effects of efficiency of mixing, catalyst, sodium hydroxide excess and chain stopper on the course of polycondensation were studied. It was found that a set of parameters can be selected such that the molecular weight of the polycarbonate depends only on the amount of chain stopper.

A series of new light-sensitive polysulfonate copolymers have been prepared by the interfacial polycondensation of mixed bisphenols and aromatic disulfonyl chlorides. The light-sensitivity bisphenols contain the styryl ketone group. These polymers exhibit good light sensitivity, and upon exposure to light they crosslink and harden to give alkali- and acid-resistant materials which are useful in photoresist applications.

Polycarbonates of different origin were heated under vacuum, and then the polymers were fractionated by the column extraction method and the molecular weight distributions were estimated. It has been found that, in the case of polycarbonates prepared by the transesteriflcation method, chain growth occurs during heating as a result of transesteriflcation. However, polycarbonates prepared from interfacial polycondensation undergo degradation, the extent of which depends on the degree of stabilization and impurities present in the polymer.

The effect of acid acceptor level (sodium hydroxide) in the interfacial polycondensation of nylon 610 has been studied. It was found that increased acceptor levels shifted the curves of intrinsic viscosity versus sebacoyl chloride concentration to the right. It was also found that peak intrinsic viscosity values first decreased and then increased with increasing acid acceptor levels. The experimental results were shown to relate to balance of reactants and character of polycondensation zone.

Synthesis of High Polymers with a Light Absorption Band in the Visible Region by Interfacial Polycondensation Reaction

Aromatic-aliphatic copolyesters synthesized by interfacial polycondensation were characterized by differential scanning calorimetry. X-ray diffraction and density measurements. A decrease in the Tg and melting temperature was observed on increasing the glycol content of the copolyesters. The wholly aromatic polyesters showed changes both in the Bragg angle position and intensity of the reflections, whereas in the aromatic-aliphatic copolyesters no sharp change was observed.