This article reports data on the dynamic mechanical and thermal behaviour of butyl acrylate‐acrylonitrile copolymers and their variation with copolymer composition. The copolymers were prepared by emulsion polymerisation techniques, using potassium peroxodisulfate initiator at 80 ± 2 °C. Films were prepared from the latex by casting and analysed by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and thermogravimetric analysis (TGA). For copolymer with 0.7 weight fraction of butyl acrylate the dynamic mechanical behaviour was identical to the synthetic rubber NBR (acrylonitrile‐butadiene rubber), such that the storage modulus shows a rapid decay with increasing temperature. The damping characteristics, as indicated by the tan δ value, increased as the weight fraction of butyl acrylate in the copolymer increased. The dynamic mechanical data has been analysed with the WLF‐Equation to study the time‐temperature relationship. The dynamic mechanical properties and glass transition data point to the formation of a copolymer, whose properties vary with acrylonitrile content. Thermogravimetric analysis revealed that weight loss occurring at a particular temperature decreases, along with the decomposition rate, with increase in acrylonitrile content. The activation energy (Ea) for the decomposition was calculated using the Coats & Redfern equation. When temperatures for 10% copolymer decomposition are compared from TGA data, the acrylonitrile rich copolymer starts decomposing at a lower temperature, but the rate of decomposition is slower and yields higher char yields.Effect of copolymer composition on the variation of tan δ (max) at a measuring frequency of 1 Hz.magnified imageEffect of copolymer composition on the variation of tan δ (max) at a measuring frequency of 1 Hz.

SynopsisTwo new polymerizable monomers, namely, 3-pentadecylphenyl acrylate and methacrylate, were synthesized starting from Cashew Nut Shell Liquid. The synthetic method used is simple, and is of general utility. These monomers were homopolymerized by bulk, solution, and emulsion polymerization techniques which yielded moderately high molecular weight polymers that showed promise as pressure-sensitive adhesive.

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In diese Untersuchungen wurden auch einige Wachsmischungen einbezogen. Dabei zeigte sich sehr deutlich der starke EintluB der Kristallinitat auf die Hoppler-Harte. Das besonders grobkristalline Adipinsauredistearylat (ADS) hat nur eine Harte von 88 bar und ist so sprode, daB bei 30 N Belastung die Priifkorper regelmaBig zerspringen (Abb. 20). Ein Zusatz von 5 Montanestenvachs ergibt ein wesentlich feinkristallineres Wachs mit einer Harte von 187 bar; welches auchBelastungenvon 24 und 30 N ohne Bruchvorgange aus-halt (Abb. 21). Noch extremer wirkt ein Zusatz von 1 0111 LDPE-Wachs-Oxidat (Abb. 22). Das resultierende Wachs ist noch wesentlich feinkristalliner und hat mit 265 bar die dreifache Harte, obwohl auch der Zusatz nur eine Harte von 133 bar hat. Man kann also Wachse durch Gefiigeveriinderungen ahnlich wie Stahl harten. Eingegangen a m 4. Febmar 1983. B y B . S . S i t a r a m a m , N. K r i s h n a m u r t i , P C . C h a t t e r j e e andM. A. S i v a s a m b a n * A variety of vinyl monomers derived from stearic acid and stealyl alcohol Vinylmonomere aus Stearindureihre Identifizierung und n e nnung hiichster Reinheit dargestellt. Ihre Trennung mittels Diinnschicht-und Gaschromatographie sowie ihre Identifizierung durch kernmagnetische Resonanzspektroskopie (NMR) werden behandelt. have been prepared i n high purity. Their by thin-'ayer and gas-ZahlreicheVinylmonomere aus Stearinssure und Stearylalkohol wurdenin liquid chromatographic techniques, as also their characterization by proton magnetic resonance spectroscopy (PMR) have been discussed. 8.5. Jahrgang Nr. 4 i!)n:+ FETTE . SEIFEN . ANSTRICHMITTEL Vinyl Monomers from Stearic Acidtheir Characterization and Separation