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Results for pilot plant scale experiments on the preparation of polycarbonates are presented. The effect of end-groups content of the oligomer on the efficiency of polycondensation was quantitatively studied and procedures of molecular weight control with different chain stoppers have been investigated. It was found that for an efficient polycondensation of oligomer the contents of the reactive groups have to be as follows: minimum 30 mole-% of OCOCl, and relation OCOCl:OH=0.5. The same applies for an effective and reproducible molecular weight control. The best effect of chain stopping is observed when a molecular weight regulator is added both in phosgenation and polycondensation stages. Es wird uber die Ergebnisse von Experimenten mit einer Versuchsanlage zur Herstellung von Polykarbonaten berichtet. Dabei wurde der Einflus des Endgruppengehaltes der Oligomeren auf die Polykondensation quantitativ verfolgt und die Methoden der Molekulargewichtsregelung mit verschiedenen Kettenabbrechern untersucht. Es ergab sich, das fur eine effektive Polykondensation der Oligomeren der Gehalt an reaktiven Gruppen mindestens etwa 30 Mol-% an OCOCl und das Verhaltnis von OCOCl zu OH mindestens 0,5 betragen soll. Dasselbe betrifft eine effektive und reproduzierbare Molekulargewichtsregelung. Der Effekt des Kettenabbruchs ist am besten, wenn der Kettenabbrecher sowohl im Phosgenierungs-als auch im Polykondensationsstadium zugegeben wird.

Interfacial polycondensation came into prominence in the 1950′s with the work of Schnell on polycarbonates, Conix on polyesters, and Wittbecker, Morgan and co-workers on polyurethanes, polyamides and other polymer classes. There were a few earlier patent references. The method has several variations and is a highly effective procedure for the rapid preparation of many polymers on a small scale. It is particularly appropriate for polymers which are thermally unstable or unmeltable, for use with volatile or unstable intermediates and for polymers with reactive functional groups. Literally thousands of polymers have been made by this process. There are a number of short-comings to the process, most of which can be overcome by adjustment of the polymerization conditions. Polycarbonates and aromatic polyamides are reported to be prepared commercially by stirred interfacial processes. Another application is the encapsulation of pesticides, inks, and other materials. As to the future, the processes are ...

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.

The possibility of an inter facial polycondensation of 1,3-bis(hydroxymethyl)-1,3-bis(γ-hydroxypropyl)- and 1,3-bis(γ-o-hydroxyphenylpropyl)-1,1,3,3-tetramethyl-disiloxanes with COCl2 is reported here for the first time, and some of the process mechanisms have been investigated. The produced polysiloxane carbonates have been found to have Mn values between 1000 and 500, to be heat resistant in air up to 250–300°C.

In recent years a number of papers and patents describing the use of interfacial reactions as a means of microencapsulation have been reported in the literature. This paper discusses the technique of microencapsulation by interfacial reactions and the effect of variables which may influence the integrity of the microcapsules. Variations of the basic interfacial polymerization techniques are described with special reference to interfacial polycondensation, the formation of polymer material by induced catalyzation, vapor deposition technique, and in-situ polymerization. Examples of some processes used and/or the types of reacting species are also included.

New polythioesters have been obtained in the interfacial polycondensation of 4,4′-di(mercaptomethyl)benzophenone with terephthaloyl, isophthaloyl and phthaloyl chlorides. The reactions were carried out at room temperature with the use of 10% excess of acid chloride per mole of mercaptan with vigorous stirring (2000 rpm). The organic phase was composed of benzene and hexane in equal volumes and the ratio of this mixture to water also was 1:1. The structure of the polythioesters was determined from elementary analysis and the infrared spectra. The molecular weight was not determined because of the very low solubility of polythioesters. Some thermal, mechanical, and electrical properties of the products have been determined. Products of dimercaptan with the terephthaloyl and isophthaloyl chlorides show the best properties.

Synthetic polymeric materials used for the preparation of asymmetric and composite membranes are examined. The reactions leading to the synthesis of these polymers and ways of obtaining a thin barrier layer which determines the principal quality parameters of the membranes are described. Attention is specially concentrated on the interfacial polycondensation reaction between acid chlorides and amines in order to create a barrier layer with a high selectivity and permeability. The bibliography includes 32 references.

Aus o,o,o′,o′-tetramethylsubstituierten Bisphenolen und Phosgen lassen sich trotz starker sterischer Hinderung der OH-Gruppen durch die Methylsubstituenten nach dem Verfahren der Zweiphasengrenzflachenkondensation hochmolekulare Polycarbonate herstellen. Voraussetzung dafur sind die Anwendung hoher Katalysatorkonzentrationen, die Aufrechterhaltung hoher pH-Werte, der Einsatz eines hohen Phosgenuberschusses und das Einhalten langer Kondensationszeiten. Die Polycarbonate zeichnen sich durch hohe Einfriertemperaturen, gute Hydrolysestabilitat, niedrige Brechungsindices und gute thermoplatische Verarbeitbarkeit aus. Das Polycarbonat aus 2,2-Bis-(3,5-dimethyl-4-hydroxyphenyl)-propan besitzt eine besonders ausgewogene Kombination von Eigenschaften, insbesondere auch gute Vertraglichkeit mit Polymeren wie Bisphenol-A-Polycarbonat, Polystyrol und Polyvinylchlorid. Highmolecular polycarbonates can be synthesized by interfacial polycondensation from o,o,o′,o′-tetramethylsubstituted bisphenols and phosgene although the phenolic OH-groups are greatly hindered sterically by the methyl groups. For the synthesis of these polycarbonates it is necessary to use high concentrations of the catalyst, high pH-values, a good excess amount of phosgene and a long condensation period. The polycarbonates are characterized by high second order transition temperatures, excellent hydrolytical stability, low refractive indexes and a good thermoplastic processability. Particularly the polycarbonate from 2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)-propane has a well balanced combination of properties, among which is a good compatibility with bisphenol-A-polycarbonate, polystyrene and polyvinylchloride.

N-Methylated polyamides and copolyamides derived from sebacic acid, N,N′-dimethylethylenediamine, and ethylenediamine were synthesized. Both interfacial polycondensation and melt poly-condensation were examined, with the interfacial generally giving the higher molecular weights. The choice of organic solvent was important in the copolyamide synthesis with hexane giving random copolyamides and the more polar chloroform yielding copolyamides with a more blocklike structure, comparable to that obtained from the melt. The softening point of the N-methylated poly-amide was between 65-75°C.

Novel examples were presented of the use in polyamide synthesis of active 2-benzothiazolyl dithiolesters for which aminolysis is assisted by a neighboring group. Solution polycondensation of new dithiolesters, 2,2′-(adipoyldithio)bisbenzothiazole and 2,2′-(isophtahloyldithio)bisbenzothiazole, with both aliphatic and aromatic diamines in polar aprotic solvents (N-methyl-2-pyrrolidone and hexamethylphosphoramide) took place rapidly at room temperature yielding polyamides with high molecular weight. The interfacial polycondensation in a chloroform–water system was also successful for polyamide formation. S,S′-Di-p-nitrophenyl dithioisophthalate reacted much more slowly toward diamines than the 2-benzothiazolyl dithiolesters. Prior to polymer synthesis, the aminolysis of active monothiolesters was carried out as a model compound study.

Aromatic polycarbonates were prepared from several dichloroformates with phosphorus-containing bisphenols, such as bis(p-hydroxyphenyl)methyl phosphine oxide and bis(p-hydroxyphenyl)phenyl phosphine oxide, or with nonphosphorus bisphenols by interfacial, low-temperature solution, and high-temperature solution polycondensation. The interfacial polycondensation gave the best results for polycarbonates, from which colorless, transparent, and fairly though films were cast. In contrast to analogous nonphosphorus polycarbonates, the phosphorus-containing polycarbonates exhibited lower polymer melt temperatures, greater range of solubility, and better self-extinguishing properties, but less stability to alkali and acid. Thermal degradation of the typical phosphorus polycarbonates proceeded in two steps, and the activation energies for the maximum rates of weight loss range from 29 to 45 kcal/mole.

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.

Durch Addition von Athylencarbonat an Piperazin im Molverhaltnis 2:1 wurde Piperazin-1,4-dicarbonsaure-bis(2-hydroxyathyl)ester (3) dargestellt. Aus 3 und aliphatischen bzw. aromatischen Dicarbonsauredichloriden entstanden alternierend aufgebaute Polyesterurethane 5 und 7, und mit 4,4′-Methylen-bis(phenylisocyanat) wurde das sequenzierte Copolyurethan 8 erhalten. Aus dem Bis(chloroformyl)-Derivat von 3 wurden durch Grenzflachenpolykondensation mit aliphatischen und aromatischen Diaminen ebenfalls geordnete Copolyurethane 11 erhalten. Bis(2-hydroxyethyl) piperazine-1,4-dicarboxylate (3) was prepared by addition of ethylene carbonate to piperazine (mole ratio 2:1). The reaction of 3 with aliphatic or aromatic dicarboxylic acid chlorides yielded alternating polyesterurethanes 5 and 7. The sequenced copolyurethane 8 was obtained by polyaddition of 3 and 4,4′-methylene bis(phenylisocyanate). Interfacial polycondensation of the bis(chloroformyl) derivative of 3 with aliphatic and aromatic diamines afforded ordered copolyurethanes of type 11.

Polyphenyl ester microcapsules were prepared by the interfacial polycondensation reactions between each of 2, 2-bis (4-hydroxyphenyl) propane and 4, 4'-dihydroxydiphenyl sulfone and each of p-phthaloyl dichloride and sebacoyl dichloride in the presence of alkali under various conditions. The percentage of reacted bisphenols, and the size distribution and mean diameters of the microcapsules formed were determined and factors affecting them were studied. The size distribution of the microcapsules was found to depend strongly on chemical structure of the reactants used. This was plausibly explained by taking account of the percentage of reacted bisphenols with the acid dichlorides. The mean diameters varied with the percentage of reacted bisphenols in a way similar to that for the size distribution.

Siloxane carbonate copolymers containing linkages in the macromolecular chains were synthesized from α,ω-bis-(β-hydroxyethoxymethyl)-dimethyl-siloxanes,2,2,-bis-(4-hydroxyphenyl)propane and their dichloroformates by low temperature and interfacial polycondensation. The effects of the ratio of components and of the length of the siloxane chain present in the oligomers on the composition and properties of the copolymers were investigated, as well as resistance to hydrolysis and optical properties. The siloxane carbonate copolymers were found to be heat resistant in air to 300°C regardless of the content and length of the siloxane chain present in them.

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.

Polyamides from 4,4′-dipiperidyl, 1,2-ethylene-, and 1,3-propylene- bridged dipiperidyls were prepared via solution and interfacial polycondensation techniques. In sharp contrast to the polyamides from N,N′-alkyl-substituted alkylene diamines and aromatic diacids, the polyamides from 4,4′-dipiperidyls are high-melting (up to 455°C) and alcohol-insoluble. Tough films were cast from formic acid solutions of the polymers; fiber of good physical properties was prepared from a formic acid solution of the polyterephthalamide of 1,2-di(4-piperidyl)ethane.

Polymers of the below form are synthesized via the interfacial polycondensation route. A study has been made of the influence of the nature of the solvents employed and base and reactant concentration. New interfacial solvent systems are presented. Durch Grenzflachenpolykondensation wurden Polymere der folgenden Struktur hergestellt. Es wurde der Einflus der Natur der Losungsmittels, der Reaktionspartner und der Basenkonzentration untersucht. Verschiedene neur Losungsmittelsysteme fur die Grenzflachenpolykondensation werden vorgeschlagen.

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.

Carboxylated polyphthalamide microcapsules were prepared by utilizing the interfacial polycondensation reaction between basic amino acids in water and p-phthaloyl dichloride in organic solvent. The yield of the microcapsules was found to be dependent on the concentration of emulsifier in the organic solvent and temperature. The microcapsules moved towards the anode in an electric field irrespective of the pH of the medium owing to the presence of carboxylic groups in the membranes. Cation binding experiments indicated an increasing order, Al3+ > Mg2+ > Cs+ > K+, NH4+, Na+ > Li+, for the binding of these cations to the microcapsules.

The use of tertiary amines and quaternary ammonium salts as catalysts for interfacial polycondensation is referred to in references [1, 2], but no detailed study of this problem has been reported on in the literature.

A series of polyamide-sulfonamides was synthesized by the interfacial polycondensation of m- and p-chlorosulfonylbenzoyl chlorides with aliphatic and aromatic diamines at room temperature. Most of the polymers obtained were high molecular weight, film-forming materials. They were all amorphous and were soluble in a wide range of acidic and basic solvents. Both aliphatic and wholly aromatic polyamide-sulfonamides showed initial breakdown in the range of 320–360°C under thermogravimetric analysis in a nitrogen atmosphere.

A series of polythiolcarbamates, [—CONH—X—NHCOS—Y—S]m, have been prepared in which X was either aliphatic or aromatic and Y was a wide variety of aliphatic groups. Synthesis of the polymers by two different methods, the tertiary aminecatalyzed solution polymerization of diisocyanates with dimercaptans and the interfacial polycondensation of bischlorothiolformates and diamines, proved that the polymers had the desired thiolcarbamate structure. Greater yields of lower molecular weight polymers were obtained by the diisocyanate method. Polythiolcarbamates were found to be highly insoluble white powders which tend to decompose in light, in hot solvents, and in aqueous base. They melt somewhat higher than their oxygen analogues, but are less thermally stable.

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.

Durch Grenzflachenpolykondensation wurde aus Hexamethylendiamin-1,1,6,6,N,N′-D8 bzw. Adipinsauredichlorid-2,2,5,5-D4 Nylon 6,6 hergestellt, das in α-Stellung zur Amidgruppe spezifisch auf der Amin- oder Saureseite (N-vicinal und CO-vicinal) deuteriert ist. Mit Hilfe der Infrarotspektren der aus diesen Proben hergestellten Filme konnen eindeutig folgende relativ starke Banden des Nylon 6,6-Spektrums zugeordnet werden: Deformationsschwingung der N-vicinalen CH2-Gruppe bei 1474/cm, Deformationsschwingung der CO-vicinalen CH2-Gruppe bei 1416/cm, Twistingschwingung der CO-vicinalen CH2-Gruppe bei 1198/cm und Twistingschwingung der N-vicinalen CH2-Gruppe bei 1179/cm. Die Lage der Deformationsschwingungsbanden dieser Gruppen ist von der Konformation zur Amidgruppe abhangig. Bei Verdrehung aus der idealen trans-Anordnung fallen δCH2(N) und δCH2(CO) bei 1435/cm zusammen. Die Unterschieden in den Bandenlagen und -intensitaten sowie deren Abhangigkeit von der Konformation lassen sich qualitativ erklaren. Hieraus ergibt sich die Forderung nach einer intramolekularen Wechselwirkung zwischen CH-Gruppen auf der Amin-Seite sekundarer Amid-Gruppen und deren π-Elektronensystem. Nylon 6,6 which is deuterated in the α-position to the amide group either in the amine (N-vicinal) or acid (CO-vicinal) component was synthesised by interfacial polycondensation using either hexamethylenediamine-1,1,6,6,N,N′-d8 or adipoyl-2,2,5,5-d4 chloride. The infrared spectra of films made from these samples showed clearly the following relatively strong bands of the nylon 6,6 spectrum which could be assigned. Scissoring mode of the N-vicinal CH2-group at 1474/cm, scissoring mode of the CO-vicinal CH2-group at 1416/cm, twisting mode of the CO-vicinal CH2-group at 1198/cm and twisting mode of the N-vicinal CH2-group at 1179/cm. The position of the scissoring modes of these groups is dependent on the conformation relative to the amide group. As a result of rotation out of the ideal trans conformation the δCH2(N) and δCH2(CO) coincide at 1435/cm. The difference in band positions and intensities as well as their dependence on conformation is qualitatively explained. Based on results an intramolecular interaction between the CH-groups adjacent to the amide group on the amine side and the π-electron system of the amide group.

CONTENTS I. Introduction?252 II. Mechanism of interfacial polycondensation?253 III. Kinetics and fundamental laws?255 IV. Comparison of equilibrium and interfacial polycondensation?260 V. Methods of carrying out interfacial polycondensation?262 VI. Macromolecular compounds obtained by interfacial polycondensation?263 VII. Conclusion?268

IN PREVIOUS reports we gave the results of investigations of the influence of different conditions on the formation of polyamides in the course of interfaciM polycondensation [1-3]. However, there still remains unanswered the problem of how the reaction rate and fractional composition of the polyamides vary during the interaction of hexamethylenediamine with adipyl chloride. I t was to answer these problems tha t the present investigation was undertaken. The variation in the reaction rate with time was determined, and the fractional Composition of the polyamide was investigated at different stages of the transformation for polyhexamethyleneadipamide films prepared under static conditions of interracial polyeondensation. .~

In order to make the conjugated fiber of PVA and nylon by interfacial polycondensation, a typical reaction employs a mixture solution of hexamethylene diamine and PVA, and a sebacyl chloride. The strength and Young's modulus of these fibers increase with the contents of PVA.According to the IR spectroscopic research and X-ray diffraction pattern, it is supposed that the chemical bonds between the nylon and the PVA would be formed, and the nylon and the PVA may also be crystallized separately.

Poly(phosphonate esters) were synthesized by base-promoted interfacial polycondensation of phenylphosphonic dichloride with thymidine and with 2-deoxy-D-ribose. The products give evidence of P-Cl endgroups. The thymidine product is a high polymer with a weight-average number of repeating units, DPw, greater than 250. The 2-deoxy-D-ribose product is separable into soluble and insoluble (crosslinked) fractions having identical infrared spectra. Xanthine is also reactive in the process employed.

sn hot water was removed from it on cooling. The products of the reaction, both the waterioluble and insoluble ones, were analysed. The part of the substance soluble in the benzeneacetone mixture was separated and studied as described above. The analytical data is shown in Table 2. The molecular weight was determined in all cases by the Rast eryoscopie method, and in some cases also by the end group method. The isocyanate and amine numbers were determined by the usual method [4].

Polyphthalamide microcapsules were prepared by the interfacial polycondensation reactions between each of 1, 6-hexamethylenediamine and diethylenediamine and each of o-, m-, and p-phthaloyl dichlorides under various conditions. The size and size distribution of the microcapsules formed were determined and the factors affecting them were of studied. Favorable conditions were suggested to obtain the microcapsules of uniform size in a high yield.

The effect of variations in polymerization condition on the size of microcapsules prepared by the interfacial polycondensation method was studied. Factors lowering the rate and degree of polymerization, such as a decrease in temperature or monomer concentration, were found to increase the microcapsule size. A mechanism was proposed for the formation of large microcapsules in the polycondensation step.

The activity of bis-[N-alkyl-(or aryl)-aminomethyl] phosphonic acids of the general formula (RNHCH2)2 $$ \cdot P\begin{array}{*{20}c} {//} \\ \backslash \\ \end{array} \begin{array}{*{20}c} O \\ {OH} \\ \end{array} $$ in the interfacial polycondensation reaction with bisphenol A has been studied. In their activity the diamines studied can be placed in the following series: R=C6H5CH2, C4H9, C6H5, C3H7.

For the synthesis of new linear polymers containing s-triazine rings in the main chain, the reaction of aliphatic dibiguanides and dicarboxylic acid chlorides has been studied.Hexamethylene dibiguanide was treated with isophthaloyl- or terephthaloyl-chloride by the interfacial polycondensation technique. The white powder so formed was soluble in sulfuric acid, formic acid, dimethyl sulfoxide, and partially soluble in o-cresol. It was insoluble in acetone and benzene.Structures of the products were discussed based on the IR spectra and TGA curves.

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.

Experimental details are given for the interfacial polycondensation of thirteen polyamides having widely different structures. The method involves the fast, room-temperature reaction in a two-phase system between diamines and diacid chlorides. Aliphatic, alicyclic, and aromatic reactants, primary and secondary diamines, and many reactants containing other functional groups are all operable. The preparations illustrate a variety of procedural modifications and point up the simplicity, rapidity, and broad applicability of the method.

Aromatic polysulfonates of high molecular weight and purity can easily be prepared by interfacial polycondensation of the disulfonyl chlorides with diphenols. The polymers were found to have a low degree of crystallinity, softening ranges in the region 200–250°C, molecular weights up to 50,000 and a thermal stability under nitrogen to above 300°C.