Polymeric phthalocyanines and their precursors, 6. Synthesis and analytical characterization of some octasubstituted phthalocyanines

Starting with 2,3,9,10,16,17,23,24-phthalocyanineoctacarbonitrile ( 3a ) different octa-substituted phthalocyanines 4a – 7a and 3b – 7b with carboxylic acid, anhydride, imido and amido groups were prepared. IR and UV/VIS spectra are discussed in detail and compared with unsubstituted phthalocyanine ( 1 ). 3 – 7 may be considered as low molecular weight analogues of polymeric phthalocyanines 2 with different end groups.     

Polymeric phthalocyanines and their precursors, 8. Synthesis and analytical characterization of polymers from 1,2,4,5-benzenetetracarbonitrile

Polymers 3 were prepared by reaction of 1,2,4,5-benzenetetracarbonitrile ( 2 ) or 2,3,9,10,16,17,23,24-(29H, 31H)-phthalocyanineoctacarbonitrile ( 5a ) with various metal salts or metals. The polymer structures were investigated by comparing their IR and UV/VIS spectra with those of 5 . Structurally uniform polymeric phthalocyanines 3 with a number of phthalocyanine units P_c ? 8, containing only nitrile end groups, were obtained from 2 or 5a with various copper salts. By saponification of 3 polymers (P_c ? 3) with carboxylic acid end groups were obtained. The reactions of 2 or 5a with other metal salts or metals yielded polymers of varying structural uniformity. Metal free 3a was also synthesized.     

Polymeric phthalocyanines and their precursors, 14. Synthesis and analytical characterization of polymers from oxy- and arylenedioxy-bridged diphthalonitriles

Phthalocyanine moieties containing polymers 3 a – e were prepared by the reaction of several oxy- and arylenedioxy-bridged diphthalonitriles 2 a – e in the absence or the presence of metal salts or metals. The structure of the polymers was thoroughly discussed on the basis of their IR and UV/VIS spectra. According to the nitrile end groups determined by IR spectroscopy, the structurally uniform polymers consist of phthalocyanine moieties. Saponification of the nitrile end groups of 3 a – e leads to polymeric phthalocyanines with carboxylic acid end groups with a lower degree of annulation than that of the polymers before saponification. The low-molecular-weight phthalocyanines 5a, b were prepared as model compounds for the polymers.     

Polymeric phthalocyanines and their precursors, 7. Synthesis and analytical characterization of polymers from 1,2,4,5-benzenetetracarboxylic acid derivatives

Structurally uniform polymeric phthalocyanines 5a – e , containing imido end groups, were synthesized by reaction of different derivatives of 1,2,4,5-benzenetetracarboxylic acid, 2a – d , with metal salts, urea and a catalyst. 5a – e were converted into polymers 3 , 4 and 6 , containing anhydride, carboxylic acid and amido end groups, respectively. IR and UV/VIS spectroscopy were used as appropriate methods for describing end groups and structural uniformity. It could be shown that the octasubstituted phthalocyanines 7 – 10 and not the phthalocyanine 1 must be considered as the low-molecular-weight analogues. The number of phthalocyanine units in the polymers was found to be ? 9. The determination of the real molecular weights is not possible, due to the low solubility of the polymers.     

Synthesis and polymerization of a amine‐terminated dendronized styrene

In this paper the synthesis of a second generation dendronized styrene macromonomer 8 with Teoc‐protected amine groups in the periphery is described, as well as its concentration dependent radical polymerization, and the liberation of the amine groups of the resulting polymer 9 a by treatment with trifluoroacetic acid to yield the novel polyamine 9 b .     

Synthesis,characterization and polymerization of dendrimers with methacrylic end groups

Dendritic methacrylic crosslinking agents were synthesized by modification of amino functional poly(propyleneimine) dendrimers. On the basis of model reactions, several experimental methods for the introduction of methacrylate end groups were evaluated. In case of the Michael reaction of 2-(acryloyloxy)ethyl methacrylate (1) the amino-end groups of the dendrimers of the second, the fourth or the fifth generation add exclusively onto the acrylic double bonds of 1 forming methacrylic end groups in the modified dendrimers. The quantitative and uniform conversion could be proved by NMR spectroscopy. Analogous dendrimer modifications were carried out with mixtures of 1 and other acrylates. The dendrimeric methacrylates of different generations were polymerized in solution and bulk at 80°C with 2.2′-azoisobutyronitrile as initiator. The polymerization enthalpy of the dendrimeric methacrylates was determined by differential scanning calorimetry and shows that the polymerization of approximately every double bond takes place. The polymerization of methacrylic dendrimers yields crosslinked polymers with glass transition temperatures near or below room temperature.     

A functional styrene monomer having a hexylamino group. Synthesis and polymerization

Synthesis and polymerization of N-hexyl-N-[2-(4-vinylphenyl)ethyl]amine ( 5 ) are reported. To elucidate the reaction mechanism for the monomer synthesis, kinetic studies are carried out on the lithium catalyzed amination reaction of styrene ( 3 ) and of 1,4-divinylbenzene ( 1 ) with hexylamine ( 2 ). The reaction rate, v, was found to be expressed as v = k [3] [2] [CH₃(CH₂)₅NHLi], where k is the rate constant. Methods for selective synthesis of 5 are considered on the basis of results of the kinetic studies. Polymerization and copolymerization behavior of 5 shows that 5 has characteristics similar to 3 in radical polymerization.     

Synthesis,characterization and polymerization of new epoxy compounds containing azomethine linkages

New epoxy compounds bearing azomethine linkages were synthesized and characterized. A series of epoxy derivatives of bis(azomethine)s ( 2a – d ) was synthesized by reacting an aromatic diamine with 4-hydroxybenzaldehyde in a 1:2 mole ratio to afford the corresponding bis(azomethine)s ( 1a – d ), and subsequent reaction with excess 1-chloro-2,3-epoxypropane in presence of a quarternary ammonium bromide as catalyst. In addition, epoxy compounds 4a, b and 5b were synthesized by reacting 1,4-benzenedicarbaldehyde with 4-aminophenol, 4-aminobenzoic acid or 5-aminoisophthalic acid in a 1:2 mole ratio and then with 1-chloro-2,3-epoxypropane. The epoxy compounds were characterized by elemental analyses as well as by IR and ¹H NMR spectroscopy. All epoxy compounds were thermally polymerized in the presence of 4,4′-sulfonyl dianiline ( 6 ). The polymerization was investigated by DTA. The thermal stabilities of the resulting polymers were evaluated by dynamic TG and isothermal gravimetric analysis (IGA). The polymers derived from diepoxy compounds are stable in nitrogen up to 293–340°C and afford an anaerobic char yield of 43–62% at 800°C.     

Functionalized monomers, 1. Synthesis and characterization of oxirane and oxetane derivatives of styrene

Optimum experimental conditions were found for the syntheses of 4-vinylphenyloxirane ( 4 ) and 4-vinylbenzyloxirane ( 9 ). The new monomer 2-(4-vinylphenyl)oxetane ( 11 ) was synthesized. All mentioned monomers are able to form polymers substituted with heterocyclic groups upon radical polymerization of the vinyl groups. Monomer 4 was found to be able to form polyether 13 containing repeating units substituted with 4-vinylphenyl groups upon complex coordination polymerization via the oxirane groups, initiated with (C₂H₅)₂AlOAl(C₂H₅)₂.     

Cationic polymerization of styrenes by protonic acids and their derivatives, 3. Propagating species in the polymerization of styrene by trifluoroacetic acid

The nature of the propagating species in the cationic polymerization of styrene by trifluoroacetic acid was investigated with special attention to the possibility of ester propagation. The molecular weight distribution (MWD) of polymers formed at 50°C in 1,2-dichloroethane (DCE) and mixtures of DCE and benzene was found to be bimodal, and increasing solvent polarity facilitated the formation of the higher polymers. From this evidence, coupled with the effects of a common ion salt on the MWD, it was concluded that the bimodal MWD results from concurrent propagation of two ionic species. ¹⁹F NMR spectra of the polymerization system in DCE at 50°C showed two peaks, one of which was assigned to the acid and the other to its styryl and polystyryl esters. The esters were formed slowly and the polymerization rate fell more rapidly than corresponded to the fall in monomer concentration. The styryl ester (1-phenylethyltrifluoroacetate) could not initiate the polymerization under the same conditions. These results indicate that an ester is not the propagating species in the present system. A kinetic treatment based on the inertness of the ester gave a satisfactory interpretation of the results.     

Thermally initiated emulsion polymerization of styrene

The thermal polymerization of styrene in emulsion was studied by determination of the number of particles, the rate of polymerization, and the average molecular weight of the polymer formed as a function of the emulsifier concentration. For the number of particles the relation N ～ [E]^1,4 was found, whereas the rate of polymerization showed a dependence of v_br ～ [E]^0,7, only up to an emulsifier content of 0,2 mol. dm^?3, but remained constant at higher concentrations. A transfer of low molecular weight radical species from the organic to the aqueous phase is discussed as a prerequisite of polymerization in the latex particles. The deviations from the Smith-Ewart theory are explained by the low rate of radical formation, which does not provide a constant radical concentration per particle.     

The asymmetric-selection polymerization of styrene oxide

The asymmetric-selection polymerization of styrene oxide was investigated by using diethylzinc/menthol system as catalyst. Monomer consumption was found to follow a second order kinetic, whereas developing of the optical rotation of the remaining monomer followed a first order reaction scheme. This phenomenon is accounted for by the assumption that the polymerization consists of rapid initiation followed by slow stepwise growth. Two moles of monomer participate in the polymerization, one of which is polymerized and the other is responsible for activation of the catalyst. The asymmetric ability of the catalyst is arising from the menthoxyl group but not from propylene oxide complexed to the catalyst.     

Photo-sensitized polymerization of styrene under high pressure

The polymerization of styrene, photosensitized by azocyclohexane-1,1′-dinitrile, was studied at 30°C over a pressure range of 1 to ca. 1000 bar. The average lifetimes of the growing polymer chains were determined by the rotating-sector method. By measuring the effect of pressure on the individual reactions of styrene polymerization, the activation volumes for the propagation and the termination were obtained as ?17,9 cm³/mol and 13,1 cm³/mol, respectively. The overall activation volume was also measured as ?17,9 cm³/mol and was nearly equal to that calculated from the individual activation volumes (?17,8 cm³/mol). The propagation rate constant increases exponentially with pressure, whereas the termination rate constant decreases rapidly up to 500 bar and then decreases slowly as the pressure increases further.     

Polymer-supported rare-earth catalysts for polymerization of styrene

A neodymium complex supported on an ethylene-vinyl alcohol copolymer (EVA · Nd) was prepared for the first time and the polymerization of styrene in the presence of a new type of catalyst system composed of this complex was studied. The new catalytic system [EVA · Nd Al(i-Bu)₃ CCl₄] (i-Bu = isobutyl) is characterized by its catalytic activity in comparison with that of conventional rare-earth catalysts. When [Nd] = 10⁻³ mol/L, [Styrene] = 5 mol/L, [Al]/[Nd] = 120 and [CCl₄]/[Nd] = 35, then the conversion to polystyrene (PS) was 55% in 6 h, and the catalytic activity reached 1972 g PS/g Nd which is higher by a factor of 45 than that of conventional rare-earth catalysts. The polymerization reaction shows a short induction period where the rate is first order with respect to the monomer concentration. The activation energy is 27,6 kJ/mol. This polymerization may proceed according to a free-radical or a Ziegler-type coordination mechanism.     

The anionic polymerization of styrene under pressure

The kinetics of the anionic polymerization of styrene were investigated under pressure (1≤p/bar < 1800) with Na⁺ as counter ion in tetrahydropyran (THP) as solvent and with Cs⁺ as counter ion in 1,2-dimethoxyethane (DME) as solvent. The results yielded the activation volume of the contact ion pair ΔV and the sum (ΔV + ΔV_cs) of the activation volume of the solvent separated ion pair ΔV and the volume change upon formation of solvent separated ion pairs from contact ion pairs ΔV_cs. The numerical values are negative. The activation volume of the solvent separated ion pairs could be estimated.     

Polymeric phospholipid analogs, 11. Synthesis and polymerization of 2-aminoethyl 2-(p-methacryloyloxybenzoyloxy)ethyl hydrogen phosphate

The preparation and characterization of 2-aminoethyl 2-(p-methacryloyloxybenzoyloxy)ethyl hydrogen phosphate (7) are described. This monomer was polymerized with 2,2′-azoisobutyronitrile (AIBN) and the properties of the resultant polymer are described.     

Initiation of polymerization with substituted ethanes, 14 Free-radical polymerization of methyl methacrylate and styrene with substituted adiponitriles

Tetraarylsuccinonitriles 1 show an atypical “stepwise” initiation mechanism in freeradical polymerization, particularly in the case of methyl methacrylate (MMA) as monomer. In the prior phase of the polymerization reaction very high concentrations of primary radicals lead to the formation of short-chain telechelics with both end groups originating from the initiator. In the further course of polymerization these telechelics are able to from radicals by release of initiator end groups and so to “re-initiate” free-radical polymerization (‘resusciatable’ radical polymerization). In this communication a general synthesis method of MMA telechelics with a formal degree of polymerization of one is presented. These 2,2,5,5-tetraaryl-3-methoxycarbonyl-3-methyladiponitriles 4 dissociate with Arrhenius activation energies in the range of 150 ± 10 kJ/mol. When using these telechelics as initiators in free-radical polymerization of MMA and styrene, respectively, above 80°C no repeated telechelic formation phase is observed and polymer formation starts immediately from the beginning. The polymers obtained have weight-average molecular weights of 200 000 to 950000 (poly(methyl methacrylate)) and 50000 to 400000 (polystyrene), respectively.     

Novel Network Polymeric Phthalocyanines: Synthesis and Characterization

Summary: New p‐xylylenebis‐(oxa‐thia‐propan) bridged metal‐free and metallophthalocyanine polymers were synthesized. The metal‐free phthalocyanine polymer ( 3 ) was prepared by the reaction of a tetranitrile monomer with 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in pentanol. Ni‐ and Co‐phthalocyanine polymers were prepared by reaction of the tetranitrile compound with the chlorides of Ni(II ) and Co(II ) in quinoline. Cu‐ and Zn‐phthalocyanine polymers were prepared by the reaction of the tetranitrile compound with the acetates of Cu(II ) and Zn(II ) and DBU in amyl alcohol. Yellow PbO and Fe(CO)₅ were used to prepare Pb‐ and Fe‐analog polymers, respectively. The Co‐phthalocyanine polymer was also prepared using ethylene glycol instead of quinoline in the presence of the catalyst ammonium molybdate. ( 3 ) was chemically doped with iodine. The electrical conductivities of the polymeric phthalocyanines measured as gold sandwiches were found to be 10⁻⁹–10⁻⁷ S · cm⁻¹ in a vacuum and in argon. The electrical conductivity of iodine doped metal‐free phthalocyanine ( 3a ) was found to be approximately 57 times higher than that of the undoped version. The extraction ability of ( 3 ) was also evaluated in THF using transition metal picrates, such as Ag¹⁺, Hg²⁺, Pb²⁺, Cd²⁺, Cu²⁺ and Zn²⁺. The extraction affinity of ( 3 ) for Ag¹⁺ was found to be highest in the heterogeneous phase extraction experiments. All the novel compounds were characterized using elemental analysis, UV‐Vis, FT‐IR, NMR and MS spectral data and DSC.

Synthesis of new network polymeric phthalocyanines.