ia poly-, FRG SUMMARYHeck reactions with anthracenecontaining compounds are investigated. Some oligomeric model compounds as well as polymers were synthesized. The reason for the failure of 9.10-divinylanthracene to undergo the Heck reaction are described. The solution of the synthetic problem was achieved by using the yet unknown 9,iO-bis(i,3-butadienyl)anthracene. 1 CHCIZ 3 CHZCl 2 L a) Part 3: cf. 10). @ 1990, Hiithig & Wepf Verlag, Basel CCC 0025-1 16X/90/$03.00 Scheme 1: 2 Br 5 Br C H LI/J2 4 9 Br 6 063 Br 6 J 7To our surprise we could not observe any reaction between 9,lO-divinylanthracene (8) and any dihalogenated anthracene. This outcome cannot be due to the lack of reactivity of the dihalogen component, since the monomer 8 is obtained from

Some reactions for the synthesis of poly(phenylenevinylene), PPV, are examined for their capability to form poly(9,lO-anthrylenevinylene). The reasons for the failure of these reactions are described. Soluble oligomers with up to seven anthracene units are synthesized. The properties of the oligomers are studied and conclusions for the properties of poly(9,lO-anthrylenevinylene), PAV, are drawn. +Ar-CH=CH+, 1Our interest in the title compound, poly(9,lO-anthrylenevinylene), is based on the fact that anthracene, acting as an electrophoric subunit, is able to accept two charges in a reduction process to form a stable dianion4). Thus, poly(9,lO-anthryleneviny-1ene)s should possess exceptional charge-storage properties and electrical conductivity in the doped state. In this paper, we describe the synthesis of soluble oligo(9,lO-anthry-1enevinylene)s. Their characterization allows prediction of the physical properties of the yet unknown poly(9,lO-anthrylenevinylene). Furthermore, the synthetic methods for the synthesis of poly(p-phenylenevinylene) are examined for their applicability on the anthrylene analoga. a) Part 2 A. Results and discussion Attempted polymerizationOur primary interest lay in the direct synthesis of the polymer. Scheme I shows all of the polymerization attempts that were conducted.Of all the reactions listed in Scheme I, merely the Horner-Emmons modification of the Wittig reaction (Scheme I, a) results in structurally uniform, but very low molecular weight products (Fn = 3-4)

The high solids semicontinuous emulsion polymerization of VAc and VeoVa10 using poly­(vinyl alcohol) (PVOH) as polymeric stabilizer is investigated. It is shown that (i) PVOH strongly affects the kinetics of the process and (ii) the formation of PVOH-graft-poly­(VAc–co-VeoVa10) leads to an overestimation of the gel content and an underestimation of the sol molecular weight when the standard characterization techniques are directly applied. A new method to properly characterize the MWD of these copolymers is presented. A mathematical model is used to analyze the effects of surfactant and initiator on the kinetics and polymer microstructure.

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The temperature dependent redox decomposition rate constants of ascorbic acid (AsAc) in aqueous solutions were quantified in the presence of ammonium iron(III) sulfate dodecahydrate (Fe-cat) and tert-butylhydroperoxide (TBHP). Decomposition rates were determined in a temperature range from 35−75 °C with respect to the component ratios. First-order kinetics were observed up to specific conversions (∼20−80%) for AsAc decomposition. The application of a flexible Weibull model provided a good and comparable description (R 2 ≥ 0.992) of decomposition processes up to high AsAc conversions (96%) at all studied reaction conditions. The activation energy was determined as a function of AsAc and Fe-cat ratios (38−79 kJ mol −1 ). Statistical modeling facilitated the prediction of rate constants. Thus, it was possible to adjust the reaction rate of emulsion copolymerizations of vinyl acetate and Versa10 in a broad temperature range (10−70 °C) by variation of the Fe-cat content.