Zbigniew Florjańczyk

Polymer-in-Salt Electrolytes Based on Acrylonitrile/Butyl Acrylate Copolymers and Lithium Salts

Solid polymeric electrolytes for battery purposes in the form of composites of lithium salts [LiI, LiN(CF3SO2)2, LiClO4, LiAlCl4, LiCF3SO3, and LiBF4] and acrylic polymeric matrixes [poly(acrylonitrile-co-butyl acrylate), poly(methyl methacrylate), and poly(butyl acrylate)] have been obtained by film casting from acetonitrile. The ionic conductivity (σ) as a function of temperature was studied by the impedance spectroscopy method. These systems show the highest σ values, on the order of 10-4−10-7 S·cm-1, at high salt concentrations (above 50 wt %), characteristic of polymer-in-salt electrolytes. The ionic conductivity and mechanical properties of composites depend on the chemical structure of the polymer matrix, the anion, and the salt concentration. The glass transition temperature (Tg) was determined from DSC studies. The introduction of a salt causes, in a majority of the composites studied, a considerable decrease in the Tg values, indicating a strong plasticizing effect. DSC studies show a multiphase...

Reactions of organoaluminium compounds with π-benzoquinone

Abstract The reactions of π-benzoquinone (BQ) with alkylaluminium compounds of the R 3 Al (R = Et, i-Bu) and RAlCl 2 (R = Me, Et, i-Bu) type have been investigated. It was found that hydroquinone and a respective alkylhydroquinone are formed after hydrolysis, from the reaction of BQ with R 3 Al; hydroquinone and a respective p -alkoxyphenol are formed from reaction of BQ with RAlCl 2 (R = Et, i-Bu). In addition to the products mentioned in the reactions above, oligomerization compounds and products resulting from the reaction of BQ with toluene (when used as a solvent) were obtained. With the aid of ESR studies it was shown from the reaction of BQ with RAlCl 2 that aluminium derivatives of semibenzoquinone are formed On the basis of the results obtained, a carbanionic mechanism for the reaction of BQ with R 3 Al (1,4-addition) and a radical mechanism for the reaction of BQ with RAlCl 2 (1,6-addition) are proposed and discussed.

On the 1,6-addition of alkylamuninium compounds to para-quinones

Ethyl, n-butyl and i-butylaluminium dichlorides undergo 1,6-addition to a conjugated bond system OCCCCO of para-quinones, Methylaluminium dichloride is inactive in this addition, and triethylaluminium gives low yields. The reactivities of the quinones vary with their electron affinites, and the highest yields of 1,6-addition are obtained in the reactions of chlorine derivatives of 1,4-benzo-quinone. The results are discussed in terms of a radical mechanism involving a homolytic cleavage of the AlC bond in the donor-acceptor complex formed between the reactants followed by combination of alkyl radicals and aluminium derivatives of semiquinone within a cage. The stable donor-acceptor complexes and aluminium derivative of semiquinone were isolated and characterized from the reactions of aluminium trichloride with 2,3,5,6-tetramethyl-1,4-benzoquinone and 2,3,5,6-tetrachloro-1,4-benzoquinone, respectively.

Reactions of ethylaluminium compounds with p-chloranil

Abstract Reactions of ethylaluminium dichloride, diethylaluminium chloride and triethylaluminium with p-chloranil have been investigated. Tetrachlorohydroquinone and p-ethoxytetrachlorophenol are the main reaction products after hydrolysis. Ethane, ethylene, butane, hexane, octane, higher aliphatic hydrocarbons, products of the chlorine substitution by an ethyl group in a molecule of p-chloranil or tetrachlorohydroquinone, and ethyltoluene or benzyltoluene isomers (when toluene was used as a solvent) may also be formed depending on the type of reactants and reaction conditions. The reactions with p-chloranil of the ethylaluminium compounds studied were found to proceed involving in the first step the formation of donor—acceptor complexes via the carbonyl group. These complexes were found to undergo reactions of two basic types. The first one is a homolytic dissociation of the AlC bond with the formation of an aluminium derivative of semiquinone and an ethyl radical. The second type of reaction is the hydrogen transfer from the ethyl group bonded with the aluminium atom to the carbonyl group of quinone with the elimination of ethylene. The reaction course leading to the formation of tetrachlorohydroquinone and p-ethoxytetrachlorophenol is proposed and discussed.

Terpolymerization of sulfur dioxide with oxiranes and cyclic anhydrides

The anionic terpolymerization in ternary systems comprising oxiranes (ethylene oxide, propylene oxide, cyclohexene oxide, epichlorohydrin), cyclic anhydrides (succinic, phthalic, maleic, glutaric) and SO 2 has been studied. It was found that SO 2 can act as a propagation catalyst and as a comonomer, which incorporated into the growing chain simultaneously with an oxirane molecule forming alkyl sulfite monomeric units. Such units are susceptible to nucleophilic attack of active centers, which leads to a back-biting and scrambling reaction. It results in the formation of macrocyclic products and gradual SO 2 elimination from the polymer chain. On the basis of studies of polymerization products and model reactions, the structures of active species and a scheme of basic elementary reactions have been proposed.

On the copolymerization of monomers from renewable resources: l-lactide and ethylene carbonate in the presence of metal alkoxides

Abstract The copolymerization of l-lactide with ethylene carbonate carried out at 120 °C in the presence of organic derivatives of aluminum, zinc and tin as catalysts leads to the formation of linear polymers of relative molecular masses in the 10 000–30 000 range containing up to 12 mol. % of carbonate monomeric units (m.u.). A decrease in Tg of copolymers down to 48 °C demonstrates the internal plasticization effect for polylactide matrix. In the first reaction step mainly lactide homopolymerization proceeds in the systems studied. Carbonate m.u. incorporate into the growing chain as a result of recurring transesterification processes. Back-biting type intramolecular transesterification reactions dominate in the system and macrocycle compounds containing 1 carbonate m.u. and 3–9 lactic acid m.u. are the main reaction products after prolonged time. On the basis of analysis of the low molecular weight products formed in the polymerization system and products of the model reaction of ethylene carbonate with metal alkoxides, the mechanism of elementary reactions leading to the incorporation of carbonate m.u. into the copolymer chains has been proposed.

Reactions of organoaluminium compounds with tetracyanoethylene and 7,7,8,8-tetracyanoquinodimethane

Abstract Alkylaluminium compounds undergo 1,2-addition to the CC bond in tetracyanoethylene and 1,6-addition to the conjugated unsaturated carboncarbon bond system in 7,7,8,8-tetracyanoquinodimethane. The relative activities of various organoaluminium compounds, the effects of complexing agents, and ESR observations indicate that the organoaluminium compound acts as a single electron donor towards the tetracyanoolefin.

On the reactivity of aromatic acrylates in free-radical copolymerization with SO2 and terpolymerization with SO2 and 1-heptene

Abstract The free-radical copolymerization of SO2 with phenyl, p-t-butylphenyl, p-nitrophenyl and 1-naphthyl acrylates and the terpolymerization of those monomers with 1-heptene were studied. The maximum content of sulphonyl monomeric units in copolymers varies from 13 to 24% depending on the induction and steric effects of the acrylic substituents. The composition of terpolymers varies over a very wide range depending on the reactant mole ratio and conversion. The composition of both copolymers and terpolymers is only affected to a small extent by temperature, contrary to the analogous reactions with alkyl acrylates.

Reactions of trimethyl- and triethylaluminium with 2,4,6-tri-t-butylnitrosobenzene

Me3Al and Et3Al undergo 1,2-, 1,4- and 1,6-addition to 2,4,6-tri-t-butylnitrosobenzene to give after hydrolysis the corresponding nitrones and oximes. In systems containing Et3Al the addition products partly undergo further reduction to aromatic amines bearing an ethyl group on the nitrogen atom or the ring. Reduction processes, leading to 2,4,6-tri-t-butylaniline, take place along with the addition reactions.

On the paramagnetic species formed in the reaction between 2,4,6-tri-t-butylnitrosobenzene and organoaluminium compounds

Abstract ESR spectra are reported for long-lived paramagnetic products formed when 2,4,6-tri-t-butylnitrosobenzene reacts with (CH3)3Al, (C2H5)3Al, C2H5AlCl2 and t-Bu3Al. The spectra are assigned to nitroxide, N-alkoxyanilino and ethyl 2,4,6-tri-t-butylphenoxyamino radicals. On the basis of the results it is suggested that nitroxides abstract a hydrogen atom from the methylene group in (CH2H5)3Al, and undergo 1,2 rearrangement under the action of C2H5AlCl2.