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Bacterially produced polyhydroxybutyrate (PHB) polymer has a lot of potential as an application for environmentally degradable plastics. We aimed in this study to blend PHB with the semicrystalline polymers poly(vinyl acetate) (PVAc) and poly(vinyl acetate-co-vinyl alcohol) (PACA) to obtain material with better physical properties. We investigated compatibility over a wide composition range using different techniques. Viscosity measurements were used to study polymer–polymer miscibility in dilute solutions with chloroform as cosolvent. The data is discussed according to the viscosity interaction parameters, which are treated as excess properties by similarity with those of real solutions. Dielectric investigations were carried out at different frequencies ranging from 100 Hz to 50 kHz. The obtained data indicated that more than one relaxation mechanism was present, which were ascribed to the rotation of the main chain and its related motions. A glass-transition temperature composition diagram, IR spectroscopy, and a morphological investigation were also used to give more information about the compatibility of such blends. The results of this study indicate that PHB/PVAc is semicompatible, whereas PHB/PACA is compatible at least in the assayed composition range of hydrolysis. We also extended the study to carry out some biological activity investigations, which were tested against the representative number of pathogenic organisms with the disk diffusion method. The different compositions of the investigated blend were biologically active when compared with the individual polymers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2363–2374, 2002

Jojoba oil-wax is extracted from the seeds of the jojoba (Simmondsia chinensis Link Schneider), a perennial shrub that grows in semi desert areas in Egypt and in some parts of the world. The main uses of jojoba oil-wax are in the cosmetics and pharmaceutical industry, but new uses could arise related to the search of new energetic crops. This paper summarizes a process to convert the jojoba oil-wax to biodiesel by transesterification with ethanol and a series of aliphatic alcohols using a more economic and energy saving method in a domestic microwave. The effect of time and power of the microwave on the extent of the transesterification using ethanol and other aliphatic alcohols has been studied. The separation of the alkyl esters from the fatty alcohols rich fraction has been done in a single crystallization step at low temperature (−18°C) from low boiling point petroleum ether. Gas chromatography has been used to follow up the transesterification process. All products have been characterized by spectral analysis., {"references":["Singh SP, Singh D. Biodiesel production through the use of different\nsources and characterization of oils and their esters as the substitute of\ndiesel: A review. Renewable and Sustainable Energy Reviews 2010; 14:\n200–216","Ma F, Clement LD, Hanna MA. The effect of mixing on\ntransesterification of beef tallow. BioresourTechnol 1999;69: 289–93.","Ratledge, Boulton CA. Fats and oils. In: Moo Young M., Blanch HN,\nDream S, Wang DIC, editors, Comparative Biotechnology in industry,\nagriculture and medicine, vol. 3. New York: Pergamon Press; 1985, p.\n983–1003.","Lee I, Johnson LA, Hammond EG. Use of branched-chain esters to\nreduce the crystallization temperature of Biodiesel. J Am Oil ChemSoc\n1995; 72: 1155–60.","European Committee for Standarisation (DIN). Automotive fuels. Fatty\nacid methyl esters (FAME) for diesel engines. Requirements and test\nmethods. European Standard EN 14214; 2003.","Alcantara R, Amores J, Canoira L, Fidalgo E, Franco MJ, Navarro A.\nCatalytic production of biodiesel from soy-bean oil, used frying oil and\ntallow. Biomass and Bioenergy 2000; 18: 515–27.","Freedman B, Butterfield RO, Pryde EH. Transesterification kinetics of\nsoybean oil. J Am Oil ChemSoc 1986; 63(10):1375–80.","Noureddini H, Zhu D. Kinetics of transesterification of soybean oil. J\nAm Oil ChemSoc 1997; 74: 1457–63.","Antolın G, Tinaut FV, Briceno Y, Castano V, Perez C, Ramırez AI.\nOptimization of Biodiesel production by sunflower oil\ntransesterification. BioresourTechnol 2002; 83(2): 111–4.\n[10] Mohamed M, Soumanoua B, Uwe T, Bornscheuer A. Improvement in\nlipasecatalyzed synthesis of fatty acid methyl esters from sunflower oil.\nEnzyme MicrobTechnol 2003; 33: 97–103.\n[11] Darnoko D, Cheryan M. Kinetics of palm oil transesterification in a\nbatch reactor. J Am Oil ChemSoc 2000; 77(12): 1263–7.\n[12] Kusdiana D, Saka S. Kinetics of transestrification in rapseed oil to\nbiodiesel fuel as tested in supercritical methanol. Fuel 2001; 80: 693–5.\n[13] Zou L, Atkinson S. Characterizing vehicle emissions from the burning\nof biodiesel made from vegetable oil. Environ Technol 2003; 24: 1253.\n[14] Kose O, Tuter M, Aksoy HA. Immobilized candida antarctica lipasecatalyzed\nalcoholysis of cotton seed oil in a solvent-free medium.\nBioresourTechnol 2002; 83:125–9.\n[15] Foidl N, Foidl G, Sanchez M, Mittelbach M, Hackel S. Jatropha curcas\nL. as a source for the production of biofuel in Nicaragua.\nBioresourTechnol 1996; 58: 77–82.\n[16] LaureanoCanoira_, Ramo´ n Alca´ ntara, M% a Jesu´ s Garcı´a-\nMartı´nez, Jesu´ s Carrasco. Biodiesel from Jojoba oil-wax:\nTransesterification with methanol and properties as a fuel. Biomass and\nBioenergy 2006; 30: 76–81.\n[17] He Y, Bao YD. Study on cottonseed oil as a partial substitute for diesel\noil in fuel for single-cylinder diesel engine. Renew Energ 2005;30:805–\n13.\n[18] Mustafa C, Ahmet E, Erol A. Performance and exhaust emissions of a\nbiodiesel engine. ApplEnerg 2006;83:594–605.\n[19] Radwan MS, Ismail MA, Elfeky SMS, Abu-Elyazeed OSM. Jojoba\nmethyl ester as a diesel fuel substitute: preparation and characterization.\nApplThermEng 2007;27:314–22.\n[20] Selim MYE, Radwan MS, Saleh HE. Performance of dual fuel engine\nrunning on jojoba oil as pilot fuel and CNG or LPG. In: Summer heat\ntransfer conference. Canada: ASME-JSME Thermal Engineering; 2007.\n[21] Ejim CE, Fleck BA, Amirfazli A. Analytical study for atomization of\nbiodiesels and their blends in a typical injector: surface tension and\nviscosity effects. Fuel 2007;86:1534–44\n[22] Busson-Breysse J, Farines M, Soulier J. Jojoba wax: its esters and some\nof its minor components. J Am Oil ChemSoc 1994; 71(9): 999–1001.\n[23] Canoira L, Alca′ntara R, García-Martínez MJ, Carrasco J. Biodiesel\nfrom jojoba oil-wax: transesterification with methanol and properties as\na fuel. Biomass and Bioenergy 2006; 30: 76–81.\n[24] Hamilton R J, Raie M Y. Structure of the Alcohols Derived From Wax\nEsters in Jojoba Oil. Chemistry and Physics of Lipids 1975; 14: 92-96\n[25] Shani A, Lurie P. Synthesis of jojobamide and homojojobamide. J Am\nOil ChemSoc 1980; 112–4.\n[26] Al-Widyan, A. Mu'taz, Al-Muhtaseb, Energy Conversion and\nManagement 51, 1702 (2010).\n[27] Silverstein R. M. Clayton Bassler G. Morrill T. C.Spectrometric\nIdentification of Organic Compounds, John Wiley, Fifth Ed. (1991).\n[28] D. Groffe, P. Groffe, S. Takhar, Petroleum Science And Technology\n19(2001) 205\n[29] Al-Sabagh A. M. NoorEl-Din M. R. Morsi R. E. Elsabee M Z. Oil\nSoluble Styrene- Maleic Anhydride Copolymer Derivatives and Their\nFlow Improver Properties of Waxy Crude Oil. J Petroleum Science and\nEngineering 65 (200)."]}

The solid-state polymerization of several dialkyl fumarates (DAF) containing different side groups have been investigated using differential scanning calorimetry (DSC). Four free radical initiators were tested with seven DAF derivatives. The type of initiator was found to have a pronounced effect on the polymerization behavior. Polymerization was confirmed mainly using NMR spectroscopy on the extracted polymers from the DSC pans. The activation energy as well as the order of the polymerization reaction for each of the investigated DAF was measured using the Ozawa method. It has been shown that DSC is an easy and versatile way to follow the kinetic of the free radical polymerization of solid monomers.

1-Cyanoethanoyl-4-acryloylthiosemicarbazide (CEATS) was synthesized for the first time as a new chelating monomer. Its structure was confirmed by both elemental and spectral analyses. Radical polymerization and copolymerization of CEATS was been carried out in dimethylformamide (DMF) in the presence of azobisisobutyronitrile (AIBN) as an initiator. Kinetic studies for the polymerization behavior of CEATS were performed. The complex formation of the CEATS monomer and polymer (PCEATS) with Cu II cation was investigated and its stability constant determined. The rate of copolymerization of CEATS with some conventional monomers, namely vinyl acetate, methyl methacrylate and acrylonitrile, was measured as a function of the mole fraction of the monomers. The reactivity ratios (r1, r2) for the various copolymer systems investigated together with the Q and e values of the CEATS monomer were determined. Moreover, the thermal gravimetric analysis of the prepared polymers and their copolymers with acrylonitrile were also studied.

Two dialkyl fumarate monomers were copolymerized with styrene and methyl methacrylate. The reactivity ratios of the monomers were calculated, and the glass transition temperature-composition diagrams for the copolymers were measured. The experimental Tg data of the copolymers were fitted to several empirical equations proposed in the literature. A comparison is made between the copolymers and the blends of the corresponding polymers. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1839–1845, 1999

Two vinyl monomers with a heterocyclic group have been prepared. The solid state polymerization of the two monomers was investigated by DSC. The activation energy as well as the order of reaction were calculated using different free radical initiators. It has been shown that the nature of the monomer and the initiator affect the behavior of polymerization. 1H NMR spectroscopy was used to confirm the polymerization.

Acrylamido and methacrylamido derivatives of isoxazole and 1,3,4-thiadiazole have been prepared. The two monomers were polymerized with a free radical initiator. The pyrolysis of the monomers, as well as of the polymers, has been investigated. The pyrolysis products were analyzed by an on line GC MS and on line pyrolysis-FTIR techniques. Pyrolysis mechanisms are proposed for the monomers and the polymers.

What is an edible packaging? An edible film or coating is simply defined as a thin film of edible material formed and sprayed on foods or food components. This package can be eaten as a part of the whole food product; it is also biodegradable, so if dumped it will disintegrate in reasonable short time. Edible films and coatings offer extra advantages such as edibility, biocompatibility, esthetic appearance, barrier to gas properties, nontoxicity, nonpolluting, and having low cost (No et al. J Food Sci 72(5):87–100, 2007). In addition, biofilms and coatings by themselves are acting as carriers of food additives (i.e., antioxidants, antimicrobials) and have been particularly considered in food preservation due to their ability to extend the shelf life. This chapter will focus mainly on edible films based on chitosan – a wonderful amazing material which is derived from the naturally occurring polymer chitin.

Radical Polymerization and Copolymerization Behavior of N -Acryloyl N ′-Cyanoacetohydrazide

Six dialkyl fumarates were pyrolyzed and their rate of gas-phase thermolysis was measured in the range 400–680 K. The activation energy for each fumarate was calculated. Product analysis using NMR, FT-IR and on-line GC/MS was used to propose a mechanism for the pyrolysis.

1-Methacryloyl-3-phenylthiourea (MAPTU) has been prepared and polymerized by a free-radical mechanism. The polymer formed has low molecular weight. The kinetic orders of the polymerization with respect to monomer and initiator, as well as the overall activation energy, were measured and found to be those expected for a free-radical scheme. This new monomer showed a tendency for cyclization to give a six-membered heterocycle. The effects of temperature and solvent on the rate of cyclization have been studied. MAPTU monomer and its homopolymer were found to form complexes with several metal ions. The stability constants of several phenyl-substituted MAPTU with Cu were measured and a correlation between log K X K H and the Hammett constant was established. The MAPTU-Cu and polyMAPTU-Cu complexes were prepared and their stability constants were calculated. MAPTU was copolymerized with styrene and acrylonitrile. The reactivity ratios have been calculated by several methods.

The dielectric loss Δe″/x was measured for dilute solutions of some N-substituted maleimides in CCl 4 and benzene in the frequency range from 0.2 to 18 GHz and temperatures between 20°C and 40°C. Methyl methacrylate was chosen for the investigation as a polar donor together with N-substituted maleimides which act as polar acceptors. The data for the monomers and the binary mixtures were analyzed by the sum of two Debye terms [sometimes one term]. The first absorption region could be attributed to the molecule as a whole, either for the pure monomer, or for their mixtures with other monomers. These monomers and their binary mixtures could have a second higher frequency absorption region which is associated with the segmental motion of the molecule. The thermodynamic parameters ΔF,ΔH and ΔS which represent the change of free energy, activation energy and entropy respectively, were obtained and discussed in terms of the molecular behavior. The variation of the relaxation time τ of the investigated mixtures in CCl4 and benzene as a function of mole fraction shows a deviation from linearity. This deviation was attributed to some sort of molecular interaction which expectedly takes place between donors and acceptors. This assumption also finds further justifications through the values of the free energy ΔF given for the different systems. The ratios between the experimental values of the relaxation times and those calculated from the individual τ when the mole fraction was taken into account are considered to be a measure for such interaction. The equilibrium constant K of the association processes is also studied by means of the dielectric polarization measurements in order to investigate the molecular interaction which might take place between the investigated compounds.

Dielectric measurements were carried out for some methyl methacrylate (MMA) and styrene (St) related polymers and copolymers in dilute solutions at a frequency range from 1 kHz to 18 GHz. The dielectric data revealed the existence of three absorption regions. The absorption region associated with the side-chain relaxation for MMA—St copolymer with a low content of MMA units, showed a diffusion-controlled relaxation which can be interpreted in terms of Kramer's theory but for large friction limits. On the other hand, all other polymers and copolymers investigated behaved according to Kramer's theory but for small friction limits. This type of polymer was found to be little affected by solvent viscosity and its dipolar relaxation process is very similar to that caused by the internal rotation of the flexible chain. In addition to the relaxation associated with the side-chain rotation, two more distinct relaxation processes are detected. That in the low frequency region is found to be due to conformational rearrangement of the main chain, while that at higher frequency could be attributed to the inner mobility of the side groups.

The rate of the gas-phase thermolysis of N-acryloyl, N′acetohydrazide has been measured in the gas phase in the range 482–517 K. This is believed to be a first order elimination reaction for which log A = 10.8 s−1 and the activation energy En = 132 kJ mol−1. Product analysis for the monomer and polymer were used for the elucidation of the thennolysis mechanism. It has been concluded that pyrolysis of the polymer occurs by depolymerization reaction followed by the pyrolysis of the monomer produced.

The rates of thermal decomposition of 1-methacryloyl-3-phenylthiourea (1a), 1-methacryloyl-3-(4-nitrophenyl)thiourea (1b), 1-methacryloyl-3-(4-chloro phenyl)thiourea (1c), 1-methacryloyl-3-(4-methylphenyl)thiourea (1d), 1-methacryloyl-3-(4-methoxyphenyl)thiourea (1e), poly-1-methacryloyl-3-phenylthiourea (2) and 1-acryloyl-3-phenylthiourea (3) have been measured between 390 and 465 K. The reactions were homogeneous and unimolecular with log A = 11.48, 11.48, 11.81, 11.43, 11.11, 11.21 and 11.87s −1 and E a = 119.7, 111.93, 120.07, 121.94, 120.84, 124.64 and 122.68 kJ mol −1 , respectively. Product analysis was used to outline feasible pathways for the elimination reaction of the compounds under study.

Two series of lightly cross-linked copolymer beads based on styrene (St) and 4-(or 2-)rinylpyridine (4VP or 2VP) were synthesized, and their equilibrium swelling behavior in aqueous solution was studied as a function of pH and ionic strength. A wide range of pH-sensitive swelling behavior could be obtained using a range of compositional changes of copolymers. Over a fairly narrow pH range, the polymer swells as the medium becomes more acidic, consistent with protonation of the VP units. With an increase in the ratio of St to 4VP, the pH at which the swelling transition occurs shifts to lower values and the extent of swells as the decreases

N-Acryloyl-N'-phenylthiourea (APTU) is polymerized by a free-radical mechanism. The polymer formed has low molecular weight. APTU is capable of polymerization in the solid state and undergoes cyclization in solution. APTU was copolymerized with styrene (St), vinyl acetate (VA), acrylonitrile (AN), and methyl methacrylate (MMA). The reactivity ratios have been calculated in each case by several methods. A unique set of Q-e parameters has been calculated by a least-squares method. The thermal stability of the St-APTU and AN-APTU copolymers was found to decrease with increasing APTU contents

Chitin has been extracted from six different local sources in Egypt. The obtained chitin was converted into the more useful soluble chitosan by steeping into solutions of NaOH of various concentrations and for extended periods of time, then the alkali chitin was heated in an auto clave which dramatically reduced the time of deacetylation. Chitin from squid pens did not require steeping in sodium hydroxide solution and showed much higher reactivity towards deacetylation in the autoclave that even after 15 min of heating a degree of deacetylation of 90% was achieved. The obtained chitin and chitosan were characterized by spectral analysis, X-ray diffraction and thermo gravimetric analysis.

A thermal degradation study has been carried out on polyacrylonitrile, polyindene and three of their copolymers using thermogravimetry and differential thermal analysis techniques. Spectral analysis (FTIR) was carried out on some of the samples before and after heating at various temperatures. Activation energy calculations for the thermal degradation process in air and under nitrogen were made using the thermogravimetry curves. The thermal analysis data showed that there was an increase in the initial decomposition temperature with increasing indene content in the copolymers, which reflects the blocking effect of indene units on the nitrile oligomerization reaction in polyacrylonitrile. A mechanism for the role of the indene comonomer in the cyclization process has been proposed.

Acrylonitrile was copolymerized with two N-arylmaleamic acids and with N-3-carboxyphenylmaleimide in dimethylformamide (DMF) using azobisisobutyronitrile as initiator. The reactivity ratios and the Q-e parameters of these monomers were estimated, and the resulting copolymers were characterized by viscosity measurements and thermal analysis. Thermogravimetry and differential thermal analysis data showed an improvement in the thermal behaviour of the investigated copolymers compared with that of poly(acrylonitrile). Mechanisms illustrating the role of both the acidic group and the maleimide ring in the nitrile oligomerization were proposed. The produced copolymers showed an excellent affinity towards basic dyes and better color fastness towards UV light. Die Copolymerisation von Acrylnitril mit zwei verschiedenen N-Arylmaleinsare-amiden als auch mit N-3-Carboxyphenylmaleimid wurde in Dimethylformamid mit Azobisisobutyronitril als Initiator ausgefuhrt. Die Copolymerisationsparameter und die Q-e-Werte dieser Monomeren wurden berechnet. Die Charakterisierung der so hergestellten Copolymeren erfolgte durch Viskositatsmessungen und Thermoanalysen. Die durch Thermogravimetrie und Differentialthermoanalyse erhaltenen Werte zeigen eine Verbesserung des thermischen Verhaltens der untersuchten Copolymeren im Verbesserung des thermischen Verhaltens der untersuchten Copolymeren im Vergleich zum Poly(acrylnitril). Ein Mechanismus, der Oligomerisierung der die Rolle der Sauren Gruppen als such der Maleimideinheiten an der Oligomerisierung der Nitrilgruppen ver-deutlicht, wurde vorgeschlagen. Die hergestellten Copolymeren Zeigen eine sehr gute Affinitat bezuglich basischer Farbstoffe und eine verbesserte Farbbestandigkeit gegenuber UV-Strahlung.

The copolymerization of indene with N-phenylmaleimide has been investigated, and the monomer reactivity ratios in these solvents were estimated. A weak charge transfer complex (CTC) between the two monomers has been suggested by the NMR measurement. Kinetic studies of the copolymerization process of these monomers reveal a participation of this CTC in the propagation step.

This paper reports briefly the results of copolymerization of ethyl methacrylate (EMA) and acrylonitrile (AN). The effect of the medium on the reactivity ratios was investigated. It was found that the medium had no effect on the value of r for EMA whereas r for AN for solution copolymerization was different from the value for bulk or emulsion copolymerizations. The values remained constant up to about 70 per cent conversion.

The donor–acceptor interaction of acrylonitrile (AN) with indene (In) has been investigated by means of ultraviolet spectroscopy and dielectric polarization measurements. The latter method yielded a value of 0.5 for the association constant of the charge-transfer-complex (CTC) and a 4.02 D for its dipole moment. The copolymerization of the two monomers was characterized by a tendency towards alternation when conducted in the bulk. This might be due to the participation of a weak CTC in the process of copolymerization. However, this tendency disappeared in polar solvents such as DMF.

The use of a sequential polymerization method for preparing interpenetrating polymer networks with biocompatible surfaces has been studied. A hydrogel monomer was made to undergo polymerization with simultaneous cross-link formation, in the presence of a swollen thermoplastic elastomer heterophase block copolymer. On removal of the swelling solvent, an interpenetrating network of the hydrogel and the thermoplastic elastomer was obtained, which absorbed water in the manner of a hydrogel, but had mechanical properties superior to hydrogels. The studies employed a poly(ether-urethane) block copolymer as the thermoplastic elastomer. The materials fabricated included samples in which the interpenetrating polymerization extended throughout the thermoplastic elastomer as well as samples in which the interpenetrating polymerization was confined to a region near the surface of the latter.

Copolymerization of N-α-naphthylmaleimide with vinylacetate was investigated in different solvents. The solvent was found to play an important role in the reactivity of the maleimide due to molecular association of solvent/monomer molecules. The overall rate of copolymerization was found to increase as the ability of the solvent to associate with the maleimide increased. ZnCl2 enhanced the reactivity of the maleimide due to a complex formation with growing radicals. The effect of substitution with a phenyl group on the reactivity of the double bond was also investigated.

The electron paramagnetic resonance spectra of cupriethylenediamine dihydroxide and cupriammonium hydroxide when complexed with cellulose, hydrocellulose, maltose, and dextrose at −160°C and at room temperature are reported. The spectra of the complexes formed indicate that the interaction is not physical but a chemical one, and the covalent character of the copper ligand has become comparatively weaker. The possibility of weak axial interaction for these complexes is shown to be unlikely, and it is proved that the nature of the interaction is a strong chemical bond between the copper and the 2,3-hydroxyl groups of the pyranoside ring of the ligand.

The surface of poly(ether urethhane) is modified by preparing gradient interpenetrating polymer networks (IPNs) with polyyacrylamide hydrogels. Soveral experimental methods are used for preparing the gradient IPNs. Attenuated total reflection Fourier transform infrared (ATR-FTIR) is used as the main characterization technique.

The copolymerization of methyl methacrylate (MMA) and N-phenyl-maleimide (NPMI) in various solvents has been studied. It has beerr shown that monomer-monomer interaction exists and leads to the formation of a weak charge-transfer complex (CTC). The CTC concentration is found to depend on the type of solvent, and its equilibrium constant depends on the dielectric constant of the solvent and increases in the order DMSO < chloroform < benzene < CC14. NMR and dipole moment measurements have been used to investigate interaction between the monomers. The monomer reactivity ratios are found to vary appreciably with the type of solvent. The data obtained indicate that changes in the reactivity ratios are due to monomer solvation or to the solvent effect on the propagating radical, rather than to the participation of the CTC in the propagation step.

A system has been designed to serve as a plasma source and has the advantage of producing plasma of known energy and controlled intensity. Poly(vinyl chloride) films were irradiated with hydrogen plasma for different intervals of time. The effect of irradiation time and storing on the extent of crosslinking was investigated. The viscosity of the soluble part decreased at the initial stage of irradiation, then increased. The crosslinking extent was observed by measuring the swelling ratio of the irradiated samples. Spectral analysis indicated the formation of carbonyl groups and polyene structure in the irradiated PVC. The mechanisms of dehydrochlorination and crosslinking are discussed. 8 figures, 3 tables.

Inspection of the polarographic behaviour of the phenylhydrazones of a variety of heterocyclic azoles having an adjacent functional group indicated that these compounds, unlike typical phenylhydrazones, are reducible in a 4-electron wave in both acidic as well as in alkaline media. A mechanism to explain the electrode processes is proposed. Polarographisches Verhalten einiger Arylhydrazono-azole Die Untersuchung des polarographischen Verhaltens der Phenylhydrazone verschiedener heterocyclischer Azole mit benachbarter funktioneller Gruppe zeigte, das diese Verbindungen im Unterschied zu typischen Phenylhydrazonen sowohl in saurem als auch in alkalischem Medium in einer Vier-Elektronen-Welle reduzierbar sind. Ein Mechanismus zur Erklarung der Elektrodenprozesse wird vorgeschlagen.

Acrylonitrile was copolymerized with three N-arylmaleimides as well as with N-octadecylmaleimide in dimethylformamide (DMF) using azobisisobutyronitrile (AIBN) as initiator. The monomer reactivity ratios were calculated by the Fineman-Ross and the Kelen-Tudős methods from which the Q- and e-parameters of these monomers were evaluated. The prepared copolymers were characterized by viscosity measurements and thermal analysis. The intrinsic viscosity decreases by increasing the maleimide content in the copolymer. Thermogravimetry TG and differential thermal analysis (DTA) data showed a remarkable improvement in the thermal behaviour of the investigated copolymers. A mechanism for the participation of the maleimide units in the nitrile oligomerization was also proposed. The investigation of the dyeing properties of the copolymers with the exception of those containing octadecylmaleimide, showed good affinity towards basic dyes as well as an appreciable improvement in their colour fastness towards UV light. Acrylnitril wurde sowohl mit drei N-Arylmaleimiden als auch mit N-Octadecylmaleimid in Dimethylformamid (DMF) mit Azobisisobutyronitril als Initiator copolymerisiert. Die Copolymerisationsparameter wurden nach Fineman-Ross und nach Kelen-Tudős bestimmt und hieraus die Q- und e-Werte der Monomeren berechnet. Die hergestellten Copolymeren wurden durch Viskositatsmessungen und Thermoanalysen charakterisiert. Die Grenzviskositat der Polymeren sinkt mit steigendem Gehalt an Maleimideinheiten. Die durch Thermogravimetrie (TG) und Differential-Thermoanalyse (DTA) erhaltenen Werte zeigen eine bemerkenswerte Verbesserung des thermischen Verhaltens der untersuchten Copolymeren. Ein Mechanismus fur die Beteiligung der Maleimideinheiten an der Oligomerisierung der Nitrilgruppen wurde vorgeschlagen. Die Untersuchung der Farbeeigenschaften aller Copolymeren mit Ausnahme derer, die Octadecylmaleimid enthalten, ergab sowohl eine gute Affinitat bezuglich basischer Farbstoffe als auch eine recht gute Verbesserung der Farbbestandigkeit gegen UV-Strahlung.

The title monomer has been prepared for the first time. It has been polymerized by a free radical mechanism in different solvents. Only oligomers were obtained so far. The dependence of the rate of polymerization on monomer and initiator concentrations has been measured and was found to follow the usual free radical scheme. The overall activation energy of polymerization has been measured in two solvents and was found to be 21.2 and 15.03 K.Cal/mol in tetrahydrofuran (THF) and N,N-dimethyl formamide (DMF) respectively. The prepared monomer has excellent chelating ability with different metal cations. The stability constant of the monomer with copper (II) ions has been measured in acetone as well as in dioxane. The complexes have no tendency for free radical polymerization.

The copolymerization of N-2-chlorophenylmaleimide with vinyl acetate was investigated at different total monomer concentrations. The reactivity of the maleimide was enhanced greatly with an increase in total monomer concentration. The overall initial copolymerization rate for the above system in two different solvents was also measured as a function of total monomer concentration, which was varied between 0.5—2.0 mol l−1.

The copolymerization of acrylonitrile (AN) with glycidyl methacrylate (GMA) has been investigated in tetrahydrofuran (THF). The reactivity ratios were estimated and the thermal behaviour of the homo- as well as the copolymers, both in air, and under nitrogen atmosphere was investigated using differential thermal analysis (DTA) and thermogravimetry (TG) techniques. GMA was found to initiate the nitrile oligomerization reaction in the copolymers upon heating. The dyeing ability, as well as the colour fastness towards UV light have also been investigated. It was found that the copolymers showed better affinity towards basic dyes compared to homopolyacrylonitrile. This affinity increases with increasing the GMA content in the copolymer. Die Copolymerisation von Acrylnitril (AN) und Glycidylmethacrylat (GMA) in Tetrahydrofuran wurde untersucht. Die Reaktivitaltsverhaltnisse wurden bestimmt und das thermische Verhalten der Homo- und der Copolymeren wurde mit Hilfe der Differentialthermoanalyse (DTA) und der Thermogravimetrie (TG) untersucht. Es wurde gefunden, das GMA beim Aufheizen die Nitriloligomerisationsreaktion initiiert. Die Anfarbbarkeit und die Bleichung in UV-Licht wurden ebenfalls untersucht. Verglichen mit Homopolyacrylnitril zeigen die Copolymeren bessere Affinitat gegen basische Farbstoffe. Diese Affinitat steigt mit zunehmendem GMA-Anteil im Copolymeren an.

The copolymerization of acrylonitrile (AN) with ethyl methacrylate (EMA) was investigated in different solvents. The highest rate was observed in dimethylformamide and the lowest in benzene. The activation energy was determined in the temperature range of 60–80°C and was found to be 82 kJ/mol. The effects of temperature and monomer concentration on the intrinsic viscosity of the copolymers were investigated. Die Copolymerisation von Acrylnitril (AN) und Athylmethacrylat (EMA) wurde in verschiedenen Losungsmitteln untersucht. Die hochste Reaktionsgeschwindigkeit wurde in Dimethylformamid, die niedrigste in Benzol gefunden. Die Aktivierungsenergie wurde im Temperaturbereich von 60–80°C zu 82 kJ/mol bestimmt. Die Auswirkungen von Temperatur und Monomerkonzentration auf den Staudinger-Index der Copolymere wurden untersucht.

The swelling properties of poly(ether urethane)s and the preparation of interpenetrating polymer networks (IPNs) from a poly(ether urethane) thermoplastic elastomer and hydrogel forming polyacrylamide have been studied. The acrylamide monomer was polymerized with simultaneous crosslink formation, in the presence of the swollen thermoplastic elastomer. Upon removal of the swelling solvent, an IPN was obtained which absorbed water in the manner of a hydrogel but had mechanical properties superior to a hydrogel.

This work deals with surface activity and corrosion inhibition efficiency of the natural polymer chitosan and its hydrophobically modified derivatives (eight polymeric compounds). Chitosan was found to be inactive at interfaces but the hydrophobic modification using different aliphatic and aromatic substituents renders the products surface active polymers. From the obtained data it was found that the surface active properties increased by increasing the hydrophobic character of these polymers. Chitosan and its based surfactants were investigated as corrosion inhibitors for carbon steel in 1 M HCl solution using the potentiodynamic polarization method. The resulted corrosion inhibition efficiency situated between 67.56% and 93.23% at 250 ppm and 25 °C. The inhibition efficiency was discussed on the light of surface active properties and the chemical structure of the used derivatives. The quantum chemical calculations were performed for some chitosan derivatives. The charge density distribution, highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), and dipole moment were considered.

The effect of ZnCl2 addition on the reactivity ratios of the system acrylonitirle (AN)-N-2-Chlorophenylmaleimide (2CMI) has been investigated. It has been found that the addition of small amount of ZnCl2 doubles the reactivity of AN while drastically decreasing that of the 2CMI. The viscosity of the copolymers has been measured and was found to decrease with increasing the maleimide and the ZnCl2 concentrations.