![]() Even when it leads to him cowering in a closet or getting his wooden chest used as a nesting ground for a colony of beavers, he’s achieved a certain level of self-acceptance that lets the show have it both ways. So when Jerry overhears a conversation (classic unintended bathroom oversharing) that these demons and Rick and Beth are taking advantage of that pride in being uncool, he’s understandably shaken. Turns out that his two kids are facing a bit of a similar dilemma with Bruce as they both do their best to soup up their own charms to win his friendship. (Summer is awfully cavalier invoking it, but it’s telling how much “ Keep Summer Safe” primes anyone watching for the ship-induced bloodshed to come.) Sensing that a bit of Interdimensional Cable and a Story Train callback won’t be enough to win him over, the three set out on a joyride in granddaddy’s space Jaguar. What starts as a jaunt through dimensions, where Mailboxians (and Femailboxians) become target practice and other aliens get blown up for sport, becomes much more dire as the Space Cruiser takes control. Propagation rate coefficients, k(p), which have been previously reported by several groups for free-radical bulk polymerizations of cyclohexyl methacrylate (CHMA), glycidyl methacrylate (GMA), benzyl methacrylate (BzMA), and isobomyl methacrylate (iBoMA) are critically evaluated. All data were determined by the combination of pulsed-laser polymerization (PLP) and subsequent polymer analysis by size-exclusion chromatography (SEC). This-so-called PLP-SEC technique has been recommended as the method of choice for the determination of k(p) by the IUPAC Working Party on Modeling of Polymerisation Kinetics and Processes. ![]() The present data fulfill consistency criteria and the agreement among the data from different laboratories is remarkable. ![]() The values for CHMA, GMA, and BzMA are therefore recommended as constituting benchmark data sets for each monomer. The data for iBoMA are also considered reliable, but since SEC calibration was established only by a single group, the data are not considered as a benchmark data set. All k(p) data for each monomer are best fitted by the following Arrhenius relations: CHMA: k(P) = 10(6.80) L. Rather remarkably, for the methacrylates under investigation, the k(p) values are all very similar. Thus, all data can be fitted well by a single Arrhenius relation resulting in a pre-exponential factor of 4.24 x 10(6) L. s(-1) and an activation energy of 21.9 kJ. All activation parameters refer to bulk polymerizations at ambient pressure and temperatures below 100degreesC. ![]() Joint confidence intervals are also provided, enabling values and uncertainties for k(p) to be estimated at any temperature.Ģ-Hydroxyethyl methacrylate (HEMA) is an important component of many acrylic resins used in coatings formulations, as the functionality ensures that the chains participate in the cross-linking reactions required to form the final product. Hence, the knowledge of their radical copolymerization kinetic coefficients is vital for both process and recipe improvements. The pulsed laser polymerization (PLP) technique is paired with size exclusion chromatography (SEC) and nuclear magnetic resonance (NMR) to provide kinetic coefficients for the copolymerization of HEMA with butyl methacrylate (BMA) in various solvents. The choice of solvent has a significant impact on both copolymer composition and on the composition-averaged propagation rate coefficient (kp,cop). Compared to the bulk system, both n-butanol and dimethylformamide reduce the relative reactivity of HEMA during copolymerization, while xylene as a solvent enhances HEMA reactivity. The magnitude of the solvent effect varies with monomer concentration, as shown by a systematic study of monomer/solvent mixtures containing 50 vol%, 20 vol%, and 10 vol% monomer. ![]()
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