Butyl rubber (also known as isobutylene isoprene rubber, IIR) containing plasticizers and cured by phenolic resin is widely used to manufacture rubber products exposed to high temperature environments. Therefore, carbon black (CB)‐filled IIR containing a petroleum‐based plasticizer [naphthenic oil (NO)] and environmentally friendly bio‐based plasticizers [soybean oil (SO) and norbornylized soybean oil (NSO)] cured by the brominated phenolic resin were studied. The NSO was prepared through the reaction of SO and dicyclopentadiene at different ratios. Gel fraction, crosslink density, curing behavior, thermal, mechanical, and aging properties of the CB‐filled IIR containing different oils were investigated. The addition of SO and NSO increased the thermal stability and decreased the crosslink density of the IIR vulcanizates compared to that of the IIR/NO vulcanizate. This was found to be due to the reaction between the phenolic resin and the bio‐based oils. Reducing the oil level increased the crosslink density of the IIR/SO and IIR/NSO vulcanizates, which in turn increased the modulus and tensile strength. Among various vulcanizates, the IIR/NSO vulcanizates showed the best overall hot air aging resistance. Results showed that NSO in the amount less than 10 phr could be a good replacement for the petroleum‐based plasticizer in IIR cured by phenolic resins. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45500.

Four model alkyds were prepared by the fatty acid process using a single fatty acid (stearic, oleic, linoleic, or linolenic acid) with phthalic anhydride and glycerol. These model alkyds were reacted with methyl methacrylate (MMA) in the presence of benzoyl peroxide or azobis(isobutyronitrile). 1 H NMR, 2D gradient heteronuclear multiple quantum coherence NMR, matrix assisted laser desorption ionization mass spectrometry, solvent extraction, and gas chromatography were used to evaluate each model alkyd system. The conversion of MMA was quantified, and the grafting mechanism of MMA onto each model alkyd was elucidated. In general, both polymerization rates and MMA conversions were inhibited in the presence of alkyd resins. For oleic alkyd model systems, the grafting site was primarily located at the double bond on the fatty acid chain. Both the homopolymerization and copolymerization of the MMA are significantly retarded by chain transfer of the hydrogen from the double allylic site in the linoleic and linolenic model systems. For the linoleic alkyd and linolenic alkyd model systems, the grafting reaction predominately occurred at the activated double allylic methylene group on the fatty acid chain via hydrogen abstraction by the primary radical and MMA radical, followed by grafting in a termination reaction with a propagating MMA radical.

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The dominant mechanism of P-wave attenuation in fluid-saturated rock is well known to be the pore-scale squirt. However, the S-wave does not change the average fluid pressure in a pore and the pore volume stays unchanged. As such, the S-wave has a mechanism of attenuation distinctively different from the P-wave. This paper attempts to resolve the mechanisms of S-wave attenuation in fluid-saturated grainstones. The first mechanism is the viscous boundary layer in a fracture, the second is fluid acceleration plus a real-number permeability and the third mechanism is fluid acceleration plus a complex-number permeability (which arises from the viscous boundary layer). D'Euville limestone and Berea sandstone are used as illustrative examples. Ultrasonic velocity and the quality factor due to pore fluid (Qs) are compared between the three models and measurement. The results indicate that fluid acceleration plus the viscous boundary layer is the mechanism of S-wave attenuation in the water-saturated grainstones. In addition, the third model reveals a novel convex in the curve of Qs in the frequency range of 107–108 Hz.