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The radical copolymerization of ethylene with vinyl trimethyl- and vinyl triethylsilanes proceeds via vinyl silane double bonds with chain termination of a bimolecular character. As the silane content of the reaction mixture rises, the reaction rate and the molecular mass of products are rapidly reduced, and the MMD and composition of the copolymers take on a unimodal character. The composition curves do not fit the Mayo-Lewis equation, but this absence of agreement is unrelated to the phase state of the system. Over the entire range of composition r sil →0. On introducing vinyl silane units to the polyethylene the frequency and temperature intervals for α and β relaxation transitions are reduced as the amount of vinyl silane units rises. A study was made of features of the temperature dependence of the heat capacity for the copolymers. It was found that at moderate temperatures crosslinking processes do not occur in the copolymers. The coefficients were found for approximate calculation of the molecular mass of the polymers using the viscosimetric method.

Some of the mechanisms for the migrational copolymerizations of aryl cyanates with aromatic carboxylic acid anhydrides, yielding a new type of polymer, i.e. polymidocarbamates, have been examined. A number of compounds modelling the main chain of these polyimidocarbamates have been synthesized. The effect of the structure of the components on the physical properties of the produced polymers was examined.

cis-1,3-Pentadiene (2) and trans-1,3-pentadiene (3) were copolymerized with isobutene (1) in the presence of (C2H5)2AlCl+(CH3)3CCl or (C2H5)2AlCl+Cl2 in the range of temperatures between —35 and —70°C. The reactivity ratios, determined at —55°C, are:r1.2=5,0 and r1.3=2,3, while the chain transfer coefficients are Kt.2=50 and Kt.3=113. The activation energies are: EMv.2= —13,8kJ/mol (—3,3 kcal/mol) and EMv.3= —16,7kJ/mol(—4,0 kcal/mol). Spectroscopic analyses (IR, 1H-NMR) showed that in both copolymers the 1,4-trans structure is prevalent over the 1,2-trans-enchainment. The fact that 3 is more reactive than 2 can be correlated with a greater electron-density (13C-NMR data) on C-1 in compound 3. cis-1,3-Pentadien (2) und trans-1,3-Pentadien (3) wurden mit Isobuten (1) in Gegenwart von (C2H5)2AlCl+(CH3)3CCl oder (C2H5)2AlCl+Cl2 im Temperaturbereich von —35 bis —70°C copolymerisiert. Die Copolymerisationsparameter, bestimmt bei —55°C, sind: r1.2=5,0 und r1.3=2,3; die Ubertragungskonstanten sind: Kt.2=50 und Kt.3=113. Die Aktivierungsenergien betragen: EMv.2= —13,8kJ/mol (—3,3 kcal/mol) und EMv.3= —16,7kJ/mol (—4,0 kcal/mol). Spektroskopische Analysen (IR, 1H-NMR) zeigten, das in beiden Copolymeren die 1,4-trans-Struktur die 1,2-trans-Verkettung uberwiegt. Die hohere Reaktivitat von 3 im Vergleich mit 2 kann durch die hohere Elektronendichte (aus 13C-NMR-Daten) am C-1 in der Verbindung 3 bedingt sein.

Mixed polycarbonates have been prepared by interfacial polymerization of the bisphenols 2,2-di-(4-hydroxyphenyl)propane (DMPP), 1,1-di-(4-hydroxyphenyl) cyclohexane (DPC), 5,5-di-(4-hydroxyphenyl)-4, 7-methanohexahydroindane (DPHMI), di-(4-hydroxyvanilidene) acetone (DVA), di-(4-hydroxyvanilidene)cyclohexanone (DVCH) and mixtures of these, with phosgene and mixtures of phosgene with the di-(acid chloride) of azidoisophthalic acid (AIPC). The composition of the polymers was determined by high resolution NMR. It is shown that copolycarbonates from DVCH and DHPP are enriched with DHPP units and a polycarbonate from DVA and DHPP with DVA units. In copolymers from phosgene, AIPC and DHPP it was found that the distribution of phosgene and AIPC radicals corresponds to the ratio of these acid chlorides in the reactant mixture.

Vnylpyridinium salts based on 4-, 2- and 2-methyl-5-vinylpyridines containing different alkylating agents polymerize rapidly in aqueous solutions if the monomeric salt concentrations are high enough (3 mole/l. or more). The reactive centres of this polymerization are of an anionic (zwitterion) character, as opposed to radical reactive centres, in view of the fact that copolymerization with acrylic acid fails to take place, and the monomer structure precludes cationic initiation. Cu 2+ ions do not inhibit the reaction, but CO 2 does. No spontaneous polymerization at all was observed with dilute solutions of the vinylpyridinium salts (less than 1 mole/l.), but it may be initiated by free pyridine or vinylpyridine additions to the reaction mixture. An analysis of the zwitterion polymerization of vinylpyridine quaternary salts leads to the conclusion that an extremely important role is played by ionic associates that appear in fairly concentrated aqueous solutions.

Polymerization of epichlorohydrin (ECH) and copolymerization of propylene oxide–allyl glycidyl ether were studied by using a catalyst consisting of aluminum alkyl–strong phosphoric acid–Lewis base. This system showed high polymerization activity for alkylene oxides, and it was elucidated by x-ray diffraction analysis that the resultant ECH polymer was completely amorphous. The polymerization was presumed to be of the coordinated anionic type. The physical properties of the vulcanized polymers were studied.

Es wurde der Verlauf des Einbaus von 6-Caprolactam und 8-Capryllactam in die Polymerketten bei der hydrolytischen, kationischen und anionischen Copolymerisation bei aquimolaren Mengen der angefuhrten Monomeren verfolgt. Bei der hydrolytischen Copolymerisation im Temperaturbereich von 200−260°C wird am Anfang der Polymerisation 6-Caprolactam schneller in die Ketten eingebaut. Mit sinkender Temperatur nimmt die Gesamtgeschwindigkeit der Copolymerisation ab, und der Unterschied zwischen den Einbaugeschwindigkeiten der Lactame steigt an. Demgegenuber wird in der Anfangsphase der kationischen Copolymerisation 8-Capryllactam grosenordnungsmasig schneller eingebaut, und die Veranderungen in der Zusammensetzung der Copolymeren sind nicht von der Temperatur abhangig. Bei der anionischen Copolymerisation werden unter den untersuchten Bedingungen beide Lactame mit gleicher Geschwindigkeit in die Polymerketten eingebaut. Den angefuhrten Unterschieden beim Einbau der einzelnen Monomeren in die Copolymerketten bei unterschiedlichem Mechanismus entsprechen die Schmelztemperaturen der in den verschiedenen Phasen der Copolymerisation isolierten Produkte. The process of incorporating 6-caprolactam and 8-capryllactam into polymer chains was studied during the hydrolytic, cationic, and anionic copolymerization in the case of equimolar ratio of the above mentioned monomers. At the beginning of the hydrolytic copolymerization at temperatures between 200 and 260°C, 6-caprolactam was more rapidly incorporated into the chains. Decreasing temperature led to a decrease in the total rate of polymerization with increasing difference between rates of incorporating the two components. Contrary to this, at the initial stage of the cationic copolymerization, the incorporation of 8-capryllactam was faster by orders of magnitude than that of 6-caprolactam, the changes of the copolymer composition being independent of temperature. Under the conditions of interest, in the course of the anionic copolymerization the two monomers were characterized with the same rates of incorporation into the polymer chains. Different melting points of products separated at various stages of the copolymerization process corresponded to the above mentioned differences in rates of incorporating individual monomers into polymer chains when different reaction mechanisms were employed.

We investigated whether vinyl chloride monomers, released from implants of vinyl chloride vinyl acetate copolymer (VCA), exerted cocarcinogenic activity and added thereby to the mechanism of foreign-body (FB) tumorigenesis. CBA/H and CBA/H-T6 mice were used. No evidence was found to indicate that chemical carcinogenic activity partakes in tumorigenesis by VCA implants. Hence it was concluded that VCA plastic is not suitable for the study of the combined process of FB/chemical cocarcinogenesis. Furthermore, experimental results obtained with VCA film implants were representative of FB tumorigenesis in the absence of demonstrable chemical carcinogenic activity.

Poly(methyl methacrylate) (PMMA) and MMA—α-methylstyrene block copolymer were reacted with polystyryl anion in mixed solvents of tetrahydrofuran (THF)—methylcyclohexane at −78°C. The changes in the concentration of the living end with the reaction time were measured photometrically. By using the analytical method of successive reactions, the rate constant of each step-wise process (k0, k1, ···, kj, ···, kn), where kj means the rate constant to form the j-th branched graft copolymer from the (j−1)-th branched graft copolymer, was estimated from the rate constant observed (kobs). It was found that kn decreased rapidly with increasing number of polystyrene branches on the PMMA molecule. The tendency of the rate constant to decrease with the progress of the reaction became more clear when the molecular weight of polystyryl anion and the volume fraction of methylcyclohexane increased. These results are discussed in some detail.

α-Methylstyrene (MS) and isobutyl vinyl ether (VE) readily polymerize, styrene (S) polymerizes to a small extent, and isobutylene (IB), butadiene (BD), and isoprene (IP) fail to polymerize in the presence of catalytic amounts of AlCl3 when propionitrile, ethyl propionate, and methyl isobutyrate are used as reaction media. MS polymerizes readily and S polymerizes with difficulty in the presence of AlCl3 to yield homopolymers when acrylonitrile (AN) is present and copolymers with ethyl acrylate (EA) and methyl methacrylate (MMA). VE readily homopolymerizes, while IB, BD, and IP fail to polymerize in the presence of AlCl3 and the acrylic monomers. VE readily homopolymerizes, S and MS polymerize to a very small extent, and IB, BD, and IP do not polymerize in the presence of ethylaluminum sesquichloride (EASC) in polar solvents. VE readily homopolymerizes in the presence of EASC and the acrylic monomers. MS polymerizes to a small extent in the presence of EASC and the acrylic monomers to yield equimolar copolymers with EA and MMA and a mixture of cationic homopolymer and equimolar copolymer with AN. S yields equimolar copolymers in low yield in the presence of EASC and the acrylic monomers. IB, BD, and IP in the presence of EASC do not polymerize to any significant extent when EA is present, form AN-rich copolymers and yield poly(methyl methacrylate) in the presence of MMA. A revised mechanism is presented for the formation of cationic, radical, random, and alternating copolymers as well as alternating copolymer graft copolymers in the copolymerization of donor and acceptor monomers.

A study was made of the effect of glycols, a catalytic complex, and copolymerization conditions on the type of hydroxyl groups of tetrahydrofuran (THF) and propylene oxide linear copolymers. It was found that the content of primary hydroxyl groups in copolymers, where diethylene glycol (DEG) is used as co-catalyst, decreases on increasing molecular weight. The rate of incorporation of DEG in the polymer chain was determined and a mechanism proposed for chain breakage by the primary hydroxyl group of oligomer alcohol. The exchange reaction between the BF3· ·THF complex and glycols was examined. Heats of formation were found for BF3· ·glycol complexes. The highest rate of exchange reaction is observed for DEG. With increased concentration of the BF3·DEG complex in the reaction medium, the content of primary hydroxyl groups in the copolymers formed decreases from 50 to 13·7%.

Aliphatic amides can be analyzed, without any preliminary treatment, by gas chromatography on porous copolymers of the Porapak type. On all of the copolymers studied, amides gave symmetrical chromatographic peaks. The best separation was achieved on Porapak N; all unsubstituted, N-methyl and N,N-dimethylamides of formic, acetic, propionic and butyric acids were separated, except for the pair N- methyl- and N,N-dimethylformamide, which were separated on Porapak Q and T. The sorption of amides on Porapak P, Q, N, R and S and on Synachrom is due mainly to non-specific interactions. Only Porapak T displays appreciable polarity; the order of retention of amides suggests that Porapak T is both an electron donor and, to a lesser extent, an electron acceptro type of adsorbent. The differences in the retentions of amides on Porapak P and Q are in accordance with the difference in the specific surface areas of these sorbents, but the sorption enthalpies are almost identical. The solute—sorbent interaction is of the same nature in both instances, regardless of an order of magnetic difference in the specific surface areas. The excellent sorption properties of Porapaks permitted the reliable determination of the response factors of amides in their detection with flame ionization and thermal conductivity detectors. ..

Differences in properties of pure metaand pure para-divinylbenzene crosslinked polystyrene and their sulphonated products have been correlated with probable network structural differences. The para-divinylbenzene copolymerizes more slowly than does the meta isomer to give a crosslinked copolymer which swells less, sulphonates less rapidly, and, when sulphonated, gives an ion exchanger which has lower selectivity. It is concluded, on the basis of copolymerization data, that the para crosslinked network is tighter and less uniform than that of the meta crosslinked network. Techniques have been developed for the synthesis, separation and purification by gas chromatography, polymerization, and copolymerization of 99.5_99.9 per cent pure metaand para-divinylbenzenes. Kinetics of the polymerization and copolymerization have been determined by radiocarbon techniques and computer analysis of high-conversion data. The preparation and sulphonation of the bead copolymers of styrene with the pure metaand para-divinylbenzenes have been developed in detail and the exchange isotherms of the sulphonated beads have been evaluated. INTRODUCTION Most ion exchange resins are prepared from styrene/divinylbenzene crosslinked copolymers in bead form by processes that are not usually specified. These processes use for divinylbenzene the commercially available mixture of the metaand para-divinylbenzene isomers. This mixture also contains varying amounts of other ingredients—chiefly metaand para-ethyistyrenes. This ambiguously defined process leads to a network structure that is difficult to obtain reproducibly, and problems are thus added to the usual complications involved in studies of crosslinked polymer systems. In our studies we have obtained data on the properties of pure metaand pure para-divinylbenzenes2'3' 8,142330; on the kinetics of their poiymerization'2'26 and styrene copolymerization4'9' 152O283233; on the characteristics of the copolymers'8' 19,25, 27 and their suiphonation" 13, 16, 18,21,24; and some data on their suiphonated products" 10, 31, Some related data have been obtained for ort.ho-divinylbenzene, 1,2,4and 1,3,5trivinylbenzenes, and a series of divinyl compounds of the type CH2 CHC6H4—X—C6H4CHCH21'6"7'20'22 57 RICHARD H. WILEY The questions for which we have sought answers are: (1) what kind of data establish a difference between the meta and the para crosslinked systems and (2) what are the structural implications available from such differentiations? It is the extent to which we can provide answers to these questions that we wish to consider in this report. D1V1NYLBENZENE MONOMERS The commercially available divinylbenzene is a complex mixture of 8—12 components. It is made by dehydrogenation of diethylbenzenes, in turn obtained by Friedel—Crafts alkylation of benzene with ethylene. The ethylbenzenes are a mixture of ortho, para and meta isomers. The ortho isomer is converted to naphthalene in the dehydrogenation and there is little to be gained in separating the ethylbenzenes prior to dehydrogenation, as the dehydrogenation catalyst re-equilibrates the isomeric mixture. One dehydrogenation process has been operated using an iodine catalyst which does not equilibrate the isomeric mixture, and during the time of its development relatively pure metaand para-divinylbenzenes were available. Also, a process23 for the separation of the divinyl isomers based on a Werner complex formation was at one time operated on a developmental basis. We have reported analytical gas chromatographic data for commercial divinylbenzene samples. Typical data are given in Figure 1. A complete listing of the components as identified by comparisons with retention times of known mixtures is given in Table 1. It is essential, for the purposes of establishing possible differences in the network systems obtained on copolymerization, that the pure meta and para isomers of divinylbenzene be separated and purified. The methods we have developed for this purpose are based on preparative gas chromatography (° _____________________________________

ABS (acrylonitrile–butadiene–styrene) terpolymer is a two-phase thermoplastic with SAN (styrene–acrylonitrile) copolymer constituting the continuous phase (matrix). The flow properties of ABS with varying molecular parameters were studied using a capillary viscometer at the shear rate range encountered in its processing. The viscosity-average molecular weights (Mv) of matrix SAN with 26% acrylonitrile content are in the range of 90,000 to 150,000, and Mv of poly-butadiene-are in the range of 150,000 to 170,000. The weight-average molecular weight of the matrix SAN is the main controlling factor for the flow properties of ABS at low shear rate, while the molecular weight distribution of the matrix SAN becomes increasingly important with the increase of shear rate. The presence of SAN grafted polybutadiene increases the melt viscosity of ABS by 40–60% over comparable free SAN copolymer and also decreases the activation energy at constant shear stress to 24–25 kcal/mole from the 33–36 kcal/mole for free SAN. The die swell of ABS and SAN can be correlated with the dynamic shear modulus G′, and the melt fracture of ABS and SAN starts at G′ equal to 3.6 × 106 dynes/cm2.

The Bushuk and Benoit theory of light scattering in copolymer systems has been evaluated for the case of a copolycarbonate of bisphenol A and poly(ethylene oxide) (1000) and for a blend of this compositionally homogeneous copolymer with a homopolymer of bisphenol A polycarbonate. The experimental conditions necessary for a successful light-scattering analysis and an estimate of the limiting sensitivity of the method are reported. The technique was disappointingly insensitive to the amount of low molecular weight homopolymer incorporated in the blend. This finding, in addition to recent reports in the literature, suggests the method has limited applicability.

Grafting of styrene vapor was carried out onto polypropylene γ-irradiated under vacuum followed by exposure to oxygen at −78°C. A comparison with the results on polypropylene irradiated in an oxygen atmosphere leads to an interesting result. Two samples were irradiated at room temperature under vacuum and in an oxygen atmosphere, respectively, the former being followed by exposure to oxygen. Although irradiation was carried out at room temperature for either sample and nearly the same amounts of the peroxy radicals are trapped, the former showed more grafting than the latter. The origin of this difference was investigated by means of electron spin resonance. Significant differences were observed in ESR spectra as well as in isothermal decays of the trapped peroxy radicals. In the former sample, the trapped peroxy radicals had a higher mobility, and consequently a significant hydrogen abstraction by the peroxy radicals was observed during storage at 40°C. This result supports the conclusion of the previous paper that the radicals effective in the grafting reaction of polypropylene preirradiated in an oxygen atmosphere are the carbon radicals which are produced by hydrogen abstraction by the peroxy radicals.

Graft cotton fibers containing poly(methyl methacrylate) were initiated by ultraviolet radiation. High-resolution NMR was used to study the nature of water absorption by these graft copolymers and also by mixtures of cotton fibers with the corresponding homopolymers. Results obtained help in investigating the structure of the copolymers and to differentiate, in a simple way, between true graft copolymers and mechanical mixtures or coated fibers.

An investigation has been made of micelle formation by a polystyrene-polyisoprene two-block copolymer in n-decane. For the sample studied the number-average molecular weights of the polystyrene block and overall copolymer chain were 13 000 and 51 000 respectively. Light-scattering studies in n-decane were made within the temperature range 25–65°C. Conventional light scattering was used to obtain weight-average molecular weights; at 25°C, M w of the micelles was 1·73±0·14×10 6 . Translational diffusion coefficients were determined from Rayleigh linewidth measurements; the micelles were found to have a hydrodynamic radius of 19·6nm at 25°C. Intrinsic viscosities were determined for the copolymer in n-decane and methyl cyclohexane within the temperature range −20° to 75°C. Finally, data obtained earlier in an electron microscopy study of freezeetched specimens were compared with the results obtained in the present study.

The equilibrium constants for the complex formation between stannic chloride and methyl methacrylate were determined in n-hexane–toluene solution at 0, −20, and −30°C by using the absorption band at 350 nm. Continuous variation plots at −20°C in n-hexane based on the 1H-chemical shifts definitely show a 1:1 interaction between the coordinated methyl methacrylate and styrene or toluene. The magnitudes of the shifts for the four groups of protons in methyl methacrylate are found to be in a specific ratio in common with the 1:2 complex–styrene or -toluene system. The equilibrium constants for the ternary molecular complex formation between the 1:2 complex and styrene or toluene were determined in n-hexane in the temperature range −50 to +20°C by use of the chemical shifts. The concentrations of the complex species in the alternating copolymerization solutions were estimated by use of the equilibrium constants. There is a linear relationship between the enthalpy and the entropy changes for the ternary molecular complex formation, which is governed by the enthalpy factor. The specificity of the interactions indicates a specific time-averaged orientation of benzene ring to the coordinated methyl methacrylate. The effects of the coordination of methyl methacrylate to stannic chloride were discussed on the basis of results of 13C-NMR spectroscopy.

Formation of charge-transfer complexes with trinitrotoluene (TNT) as a common acceptor was studied in detail by using dimethyltoluidine (DMT), poly-N-dimethyl-p-aminostyrene (poly-ASt), and also copolymers of aminostyrene (ASt) and styrene (St) as donors. A smooth bathochromic shift in λmax was observed with increasing ASt unit content in copolymers. Values of the constant for charge transfer complex formation KCT were found to increase smoothly with ASt unit content. However, the KCT value with DMT did not coincide with the value extrapolated from the plot of KCT value versus ASt unit content to zero ASt unit content, but was found to be much higher than the limiting value, in contradiction to the results obtained with maleic anhydride (MAnh). The entropy of complex formation with DMT was found to be exceptionally small; this small value may be responsible for the high KCT value with DMT.

A polymer–rhodium complex prepared from rhodium(III) chloride and styrene-divinylbenzene copolymer with iminodiacetic acid groups is found to catalyze the heterogeneous hydrogenation of alkenes in polar solvents at 30°C under an atmospheric hydrogen pressure. The polymer complex hydrogenates selectively the ethylenic double bonds in the alkenes with carbonyl and aromatic groups. The rates of hydrogenation of alkenes by the polymer complex are found to be markedly affected by the steric hindrance of the substrates.

Conventional emulsion polymerization of styrene produces some polydispersion in particle sizes in the latex. By carrying out a one-stage polymerization of finely emulsified monomer droplets of styrene formed in a mixture of methanol and water, it is possible to prepare stable latices of polystyrene in which the particles are perfectly uniform in size. The polymer has a relatively low molecular weight, but it is more stable to fragmentation by surfactant solutions than polystyrene prepared by conventional emulsion polymerization, the molecular weight of which is greater. The surface charge density of the particles is higher than that of particles produced by emulsion polymerization, and this probably accounts for the stability of the dispersion during polymerization and of the latex.

A terpolymer of butadiene–styrene–vinylpyridine has been crosslinked by addition of iron chloride. Differential enthalpic analysis gives evidence of a two-phase system. Electron microscope studies at 0.1 and 1 MeV show the existence of precipitates. The majority of these ironrich aggregates have diameters less than 100 A. Their form is polyhedral but very nearly spherical. No crystallinity has been detected inside the clusters. Thus the existence of strong interactions as in crystals of FeCl3 hydrates is excluded.

The effect of pressure on the radiation-induced cross-linking of synthetic rubbers, cis-l,4-polybutadiene, cis-l,4-polyisoprene, poly(TFE-propylene), poly(styrene-butadiene), poly(ethylene-propylene), and trans-l,4-polybutadiene were studied. A remarkable acceleration of cross-linking by compression for unsaturated polymers is attributed to an acceleration of the propagation reaction of cross-linking, which does not require long-range migration of radicals, by reduction of the distance between polymer chains at high pressure while the termination reaction, which requires long-range migration of radicals to recombine with each other, is reduced by the decrease in mole-cular mobility at high pressure. The presence of an optimum pressure was observed for radiation-induced cross-linking of cis-l,4-polyisoprene and TFE-propylene copolymer. This is explained by a significant change in molecular motion occurring due to the glass transition or crystallization at high pressure.

The synthesis and homopolymerization of acryloyl N,N,-bis(2,2-dimethoxyethyl)amine is described. Gel networks were obtained by copolymerization of acryloyl N,N,-bis(2,2-dimethoxyethyl)amine and N,N,′-methylenediacrylamide (molar ratio 8:1) and by copolymerization of acryloyl morpholine, acryloyl N,N,-bis(2,2-dimethoxyethyl)amine and N,N,′-methylenediacrylamide (molar ratio 8:2:1). Following treatment of the gel networks with tartaric dihydrazide in dilute hydrochloric acid and subsequent activation with nitrous acid, conjugates of β- d -glucosidase were prepared. In both cases the immobilized enzyme was more resistant to heat denaturation than the native enzyme in solution. The nature of the polymer-enzyme linkage is discussed with reference to studies on the model compound phenylacetyl N,N-bis(2,2-dimethoxyethyl)amine.

Polypeptides derived from L-naphthylalanine and γ-benzyl L-glutamate were prepared. Conformational properties in solution were investigated by circular dichroism (CD) and infrared spectra on the soluble copolymers, and the copolymers were assumed to take the right-handed α-helical conformation. By the addition of trifluoroacetic acid, a transition of side-chain arrangement is induced simultaneously with the conformational transition of the peptide backbone for the copolymer with the highest content of L-naphthylalanine residues. Fluorescence spectra of the copolymers show no excimer emission, which is evidence for the rigid orientation of the side-chain naphthyl groups. The infrared spectrum and x-ray diagram of poly-L-naphthylalanine do not rule out the helical conformation in the solid state.

The terpolymerization of sulfur dioxide, butene-1 and acrylonitrile affords terpolymers containing equimolar amounts of sulfur dioxide and butene-1 with various acrylonitrile contents. Ultraviolet irradiation was found to accelerate the polymerization and decrease the acrylonitrile content in the polymer. This fact is interpreted by a mechanism through a copolymerization of sulfur dioxide–butene-1 complex and acrylonitrile, whereby the polymerizability of sulfur dioxide–butene-1 complexed monomer may be accelerated by ultraviolet light. In fact, a binary system of sulfur dioxide and butene-1 was found to be accelerated by ultraviolet irradiation, and it affords a maximum rate at a 1:1 composition of feed monomer. Ultraviolet light of 250–300 mμ wavelength is effective for the initiation and the propagation. This may be ascribed to the ultraviolet absorption of the sulfur dioxide–butene-1 complex. The temperature coefficient was measured in both dark and ultraviolet irradiation reactions. The ultraviolet irradiation enhances the reactivity of sulfur dioxide–butene-1 complexed monomer at low temperature. In the terpolymerization with sulfur dioxide, isoprene, and butadiene, the ratio of isoprene and butadiene in the terpolymer was not altered by ultraviolet irradiation because both monomers from complexes with sulfur dioxide, perhaps having the same temperature coefficient for the polymerization.

An experimental study of the influence of carbon black loading, particle size, and structure on the extrusion characteristics of polybutadiene and butadiene–styrene copolymer synthetic rubber is described. The development of extrudate distortion and its mechanisms are considered. The viscosity and die swell have been related to black loading, particle size, and structure. Generally, it is found that black surface area and structure acts to increase viscosity and decrease elastic memory. This situation is analyzed in terms of the theory of nonlinear viscoelasticity. Two mechanistic theories are described which may explain this behavior. One theory is based on the continuum mechanics analysis of suspensions of particles in viscoelastic media. The rheological behavior of the black compounds is explained in terms of the increased severity of deformation in the polymer matrix surrounding the particle agglomerates. The second theory is based on the view of an entanglement network containing black particles. Polymer chains may be adsorbed onto the surface giving rise to increased entanglement densities.

De nouveaux derives de la phenothiazine (1a) ont ete prepares: la methyl-10 vinyl-3 phenothiazine (1c), le poly[(phenothiazin-3 yle)-1 ethylene] (3a) (poly(vinyl-3-phenothiazine)) et des copolymeres du methacrylate de methyle et de la vinyl-2-phenothiazine (2). Les proprietes des complexes a transfert de charge, forme par ces polymeres et copolymeres avec quelques accepteurs d'electrons, sont decrites. En particulier, les proprietes photochromes de certains complexes de la phenothiazine (1a) sont conservees, lorsque le groupe phenothiazinyle est introduit dans un milieu macromoleculaire. Les mecanismes des reactions photochimiques et leurs cinetiques ont ete etudiees pour les sytemes suivants: copolymere methacrylate de methyle/vinyl-2 phenothiazine + accepteur en solution et sous forme de films; phenothiazine + accepteur disperses dans une matrice solide de poly(methacrylate de methyle). Some new phenothiazine derivatives were prepared, namely 10-methyl 3-vinyl phenothiazine (1c), poly[1-(3-phenothiazinyl) ethylene] (3a) (poly(3-vinylphenothiazine)) and copolymers of methyl methacrylate and 2-vinylphenothiazine (2). The properties of the chargetransfer complexes between these polymers and copolymers and some electron acceptors are described. It could be shown that the photochromic properties of some phenothiazine complexes are retained when the phenothiazinyl group is inserted in a macromolecular medium. The photochemical reaction mechanisms and kinetics were studied in the following systems: methyl methacrylate/2-vinylphenothiazine (2) copolymers + acceptor, in solution and in the form of films, and phenothiazine + acceptor dispersed in a solid poly(methyl methacrylate) matrix.

High resolution 19F NMR spectra and IR absorption spectra of vinylidene fluoride (VF) and hexafluoracetone (HFA) copolymers containing up to 31 mole % HFA were obtained. It was shown that polymerization takes place by opening the carbonyl double bond. A small part of HFA is added to polymer chain ends with retention of the carbonyl group. HFA units are mainly combined with an oxygen atom to the CF2 group of VF and with a C(CF3)2 group to the CH2 group. It was found that HFA units are absent from copolymer molecules. VF units and alternating segments of copolymer units are mainly formed by the “head-tail” type. The existence was indicated of a conformation transition in VF units and a transition related to rotation of HFA units. Conditions of these transitions were examined. A relation was derived to determine copolymer composition. It was shown that the distribution of monomer nits in copolymer molecules conforms to the statistics of first order Markoff chains. Copolymerization constants were determined.

Evidence is given that, when solutions of diene monomers and anthracene in tetrahydrofuran are reacted with alkali metal and subsequently titrated with linking agents such as alkyl dihalides, copolymers are formed; they contain the 9,10-dihydroanthracene adduct and the diene in the same proportion as in the original solution. The structures of these copolymers have been elucidated by NMR spectroscopy and the mechanism of formation is discussed.

A free-oscillating torsional pendulum was used to investigate the effect of the concentration of the HO—CH2—CH2—COO— and NH2 CO— side chains and α-methyl groups of the main chains on the mechanical relaxation behavior of polymethacrylate and polyacrylate polymers and copolymers in the glassy state. The intensity of the low-temperature (γ) dispersion is linearly proportional to the volume fraction of 2-hydroxyethyl methacrylate (HEMA) in both series of copolymers and is independent of the content of the α-methyl groups. The temperature of the γ-dispersion, which for PHEMA is about —133°C (1 Hz), is lowered by the incorporation both of methacrylamide (MAAm) and—although to a lesser extent—of acrylamide (AAm) units. The secondary (β1) process of PHEMA (28°C; 1 Hz) is shifted toward higher temperature with increasing amount of MAAm, so that for the dry PMAAm it cannot be observed at temperatures up to 120°C. On the other hand, PAAm is characterized by the secondary relaxation at —25°C (1 Hz); however...

Graft Copolymerization onto Cellulose Derivatives. IV. Graft Copolymerization of Styrene and Styrene—Methyl Methacrylate onto Cellulosic Materials Containing Carbonyl and Carboxyl Groups

Analysis of the solution fractionation of ethylene–propylene copolymers was carried out by assuming a bivariate normal distribution function for the distribution of molecular weight and chemical composition. It was found that the variation of the molecular weight and composition distributions in fractions was complicated, because two distribution characteristics of the original copolymer affect fractionation to differing extents. The hypothetical cumulative weight distribution curves thus obtained agreed essentially with those obtained experimentally.

The ability of styrene–methyl methacrylate copolymers to stabilize silica dispersions has been investigated. Random, block, and graft copolymers covering the entire composition range have been employed in carbon tetrachloride, trichloroethylene, and benzene solutions. Equilibrium sediment volumes and dispersion turbidities provide adequate and concordant estimates of stabilization efficiency. Polystyrene is not adsorbed by precipitated silica from trichloroethylene or benzene and does not stabilize dispersions in these liquids; although adsorbed from carbon tetrachloride, there is no stabilization. Poly(methyl methacrylate) is an efficient dispersion stabilizer, and its performance is independent of molecular weight over a wide range. Random copolymers having styrene contents in excess of ca. 60% do not stabilize in trichloroethylene but do so in carbon tetrachloride, although well adsorbed in both cases. With this major exception, and that of a low-styrene graft copolymer in carbon tetrachloride, copolymers of all structures and compositions stabilize well, better than poly(methyl methacrylate) in the solvents examined. A substantial degree of surface coverage is necessary for optimum stabilization. Subsidiary solution adsorption and layer thickness measurements are also reported.

Glassy carbons containing iron were prepared from copolymers of furfuryl alcohol and ferrocene derivatives at heat-treatment temperatures from 500°C to 2500°C. The copolymerization produced a highly dispersed state of iron in carbonaceous matrices at least in the early stage of pyrolysis. Above 500°C, the homogeneously dispersed iron separated into irregularly spaced domains consisting of cementite, pure iron and iron compounds of unknown composition. Addition of iron resulted in a local graphitization of the glassy carbon at heat-treatment temperatures above 1000°C. At heat-treatment temperatures between 500°C and 800°C, electrical resistivities of the iron-doped carbons were much smaller than those of unmodified polyfurfuryl alcohol carbons but followed more or less the behavior of the latter for heat-treatment temperatures above 800°C.Measurements of mechanical properties indicated a remarkable increase in tensile strength of the low temperature carbons (500°C) with increasing iron content but the strength of the iron containing carbons decreased at higher carbonization temperatures.

Durch radikalisch initiierte Losungspolymerisation in DMSO wurden Homopolymere und Copolymere des 8-Vinylalloxazins (1) dargestellt, deren Austauschkapazitat, Bindungsvermogen fur Ag+-Ionen und Redoxeigenschaften untersucht wurden. 3,4-Diaminostyrol konnte polymerisiert und polymeranalog mit Alloxan zu einem polymeren Alloxazin umgesetzt werden. Homopolymers and copolymers of 8-vinylalloxazine (1) were prepared by radically initiated solution polymerization in dimethyl sulfoxide. Their exchange capacity, ability for binding Ag+ ions and redox properties were investigated. 3,4-Diaminostyrene was polymerized and reacted with alloxane by polymer-analogous reaction to polymeric alloxazine.

Copolymers of p-vinylphenol were prepared in bulk with heptafluorobutyl and pentadecafluorooctyl acrylates and trifluoroethyl, hexafluoroisopropyl, heptafluorobutyl, octafluoropentyl and pentadecafluorooctyl methacrylates using azobisisobutyronitrile as the initiator in sealed tubes. Intrinsic viscosities of the copolymers ranged from 0.44 to 1.85. Monomer reactivity ratios for copolymers of trifluoroethyl methacrylate (M1) were: with hydroxyethyl methacrylate (M2), r1 = 0.47, r2 = 1.0; with methyl methacrylate (M2), r1 = 0.82, r2 = 0.50; with styrene (M2), r1 = 0.29, r2, = 0.20; and with p-vinylphenol (M2), r1 = 0.096, r2 = 1.5. Q and e values of trifluoroethyl methacrylate were 1.30 and 0.92, respectively. Monomer reactivity ratios of octafluoropentyl methacrylate (M1) were: with styrene (M2), r1 = 0.26, r2 = 0.20; and with p-vinylphenol, r1 = 0.21, r2 = 1.5. Q and e values for octafluoropentyl methacrylate were 1.27 and 0.92, respectively. Critical surface tensions of the homopolymers ranged from 17.9 to 14.8 dyn/cm. A copolymer of hexafluoro-i-propyl methacrylate and p-vinylphenol exhibited a critical surface tension of 16.5 dyn/cm.

Copolymerization of 2-hydroxyethyl methacrylate with methacrylamide or acrylamide and a crosslinking agent in the presence of water or other diluents yielded transparent hydrogels with a varying degree of swelling and varying sorption properties. The equilibrium degree of swelling increases with increasing content of amide groups and exhibits a maximum at ca. 60 wt-% methacrylamide. The temperature dependence of swelling at 25–50°C changes from negative to positive with growing content of methacrylamide in the copolymer. The effect of the introduction of the amide groups can be interpreted by a weakening of the extent of hydrophobic interactions and by an increase in the role played by the hydrogen bonds. At the same time, the swelling-in effect of the salting-in anions decreases and the sensitivity to the sorption of metal cations increases. The increasing content of methacrylamide is reflected in an increase in the modulus, tensile strength, and elongation-at-break in gels swollen to the same degree. In gels swollen in water to equilibrium, the positive effect of methacrylamide units is compensated for by the negative effect of the increasing degree of swelling, so that the mechanical properties of these gels do not depend too much on the composition of the copolymer. The increasing content of acrylamide in the copolymer strongly raises the degree of swelling, which is reflected in poorer mechanical properties compared to poly(2-hydroxyethyl methacrylate).

A mathematical analysis is developed to compute the sequence structure resulting from the interchange reactions that occur with condensation polymers. Computed examples demonstrate the flexibility and limitations of this synthesis technique in attaining novel block copolymers.

The examination of 13C-NMR spectra of some unsaturated homopolymers (polyalkenylenes and polypentadienes) has shown that it is possible to distinguish beween 1,2-and 1,4-structures and between cis- and trans-configuration of the double bonds along the chain. By using this technique, it has been possible to obtain evidences on the structure and the relative orientation of monomeric units in alternating copolymers of isoprene with acrylonitrile or propene. Copolymers of butadiene with these two latter comonomers were also examined by this method. Die Untersuchung von 13C-NMR-Spektren von ungesattigten Homopolymeren (Polyalkenylenen und Polypentadienen) hat gezeigt, das man zwischen 1,2- und 1,4-Strukturen und zwischen einer cis- und trans-Konfiguration der Doppelbindungen entlang der Kette unterscheiden kann. Durch Anwendung dieser Technik ist es moglich geworden, Klarheit uber die Struktur und die relative Orientierung der Monomerinheiten in alternierenden Copolymeren des Isoprens mit Acrylnitril oder Propen zu erhalten. Mit derselben Methode wurden auch Copolymere des Butadiens mit den beiden letzteren Comonomeren gepruft.

The decay behavior of cellulose radicals produced by photo-irradiation at room temperature and the characteristics of photo-irradiated cellulose samples to initiate graft copolymerization of methyl methacrylate (MMA) were investigated. ESR spectra of such untreated, swollen, oximated, and ferric ion-sensitized samples irradiated at room temperature were constructed mainly of a single absorption line with a line width of 20 to 22 gauss and a g value of 2.003, and it is surely conceivable that the radicals showing a singlet spectrum should agree with those of alkoxy end produced at either the C1 or C4 position of the glucose unit by the scission of glucosidic bonds. The decay of radicals was accelerated by contact of various solvents with the samples, the activity decreasing in the order, water ≈ methanol ≫ acetone > dioxane. On the other hand, the decay of radicals by vinyl monomers became smaller in the order, methacrylic acid > MMA ≈ styrene. Graft copolymerization of MMA by a photo-irradiated sample was effectively initiated with the use of a certain amount of water or methanol, but not with acetone and dioxane. As no initiation can occur with the unirradiated sample, it is concluded that the initiation of graft copolymerization on the photo-irradiated sample is attributable to cellulose radicals showing a singlet spectrum which are formed in photo-irradiation at room temperature.

Male Sprague-Dawley rats (225?250 g) were exposed to the thermal degradation products from four fluoropolymers. The three polymers containing vinylidene fluoride and hexafluoropropene (VF2/HFP) were pyrolyzed at 550? and 800?C, whereas polytetrafluoroethylene (PTFE) was pyrolyzed at 625 and 800?C. At the lower temperatures, the pyrolysate from the copolymer of vinylidene fluoride and hexafluoropropene (VF2/HFP) was less toxic than the pyrolysates from either the terpolymer of vinyidene fluoride, hexafluoropropene, and tetrafluoroethylene (VF2/HFP/TFE) or the copolymer of vinylidene fluoride and hexafluoropropene with ?additives? (VF2/HFP-A). However, the pyrolysates from the VF2/HFP-containing materials produced less toxic products than the pyrolysate from PTFE at 625?C. When the pyrolysis temperature was increased to 800?C, very little difference was noted between the pyrolysis toxicity for any of the VF2/HFP-containing polymers with the most toxic pyrolysate again produced by PTFE. Carbon monoxide levels were all sublethal. No correlation could be established between hydrolyzable fluoride levels and the lethality of the pyrolysates. Death following exposure occurred within 48 hr due to acute pulmonary edema and hemorrhage. Survival of this acute phase was followed by alveolar lymphocytic infiltration and peribronchial tissue proliferation.

The copolymer composition equation for both terminal and penultimate models, was derived by applying a variational principle to the informational entropy of the copolymer. Die Copolymerisationsgleichung wurde sowohl fur das „terminal”- als auch fur das „penultimate”-Modell unter Anwendung eines Variationsprinzips auf die Informations-entropie des Copolymeren abgeleitet.