Kinetics of CH2=CHCH2OCF2CF2H with atmospheric oxidants
Authors: Blázquez Sergio , McGillen Max R. , Ren Yangang , Albaladejo José , Mellouki Abdelwahid , Jiménez Elena 
Published: March 2021

&lt;p&gt;As industries transition towards greener business models, many mass-produced chemicals are being replaced by low-global warming potential (GWP) alternatives. Allyl 1,1,2,2-tetrafluoroethyl ether (CH&lt;sub&gt;2&lt;/sub&gt;=CHCH&lt;sub&gt;2&lt;/sub&gt;OCF&lt;sub&gt;2&lt;/sub&gt;CF&lt;sub&gt;2&lt;/sub&gt;H) represents a potential replacement candidate. This molecule contains an olefinic bond, several abstractable hydrogen atoms, an ether linkage and a non-perfluorinated side-chain. As such it can react with various atmospheric oxidants in a variety of degradation mechanisms, each of which may serve to reduce its atmospheric lifetime and its impact upon the environment. Before widespread usage, it is crucial that these environmental sinks are quantified such that the risk that CH&lt;sub&gt;2&lt;/sub&gt;=CHCH&lt;sub&gt;2&lt;/sub&gt;OCF&lt;sub&gt;2&lt;/sub&gt;CF&lt;sub&gt;2&lt;/sub&gt;H poses to the environment can be thoroughly assessed. We present measurements of gas-phase relative rates with hydroxyl radicals (OH), atomic chlorine (Cl), ozone (O&lt;sub&gt;3&lt;/sub&gt;) and nitrate radical (NO&lt;sub&gt;3&lt;/sub&gt;) carried out in HELIOS simulation chamber at CNRS (Orl&amp;#233;ans, France) as described by Ren &lt;em&gt;et al&lt;/em&gt;.&lt;sup&gt;1&lt;/sup&gt; and references within. Although previous measurements are available for OH&lt;sup&gt;2&lt;/sup&gt; and Cl,&lt;sup&gt;3&lt;/sup&gt; we find some discrepancies in comparison to our new determinations. In the case of O&lt;sub&gt;3&lt;/sub&gt; and NO&lt;sub&gt;3&lt;/sub&gt;, these represent the first such measurements of which we are aware. Furthermore, we have determined the absolute rate coefficient of CH&lt;sub&gt;2&lt;/sub&gt;=CHCH&lt;sub&gt;2&lt;/sub&gt;OCF&lt;sub&gt;2&lt;/sub&gt;CF&lt;sub&gt;2&lt;/sub&gt;H + OH using a pulsed-laser photolysis&amp;#8211;laser-induced fluorescence technique between 273 and 363 K performed at the Physical Chemistry department of UCLM (Ciudad Real, Spain) as described by Bl&amp;#225;zquez &lt;em&gt;et al&lt;/em&gt;.&lt;sup&gt;4&lt;/sup&gt; and references within, representing the first temperature-dependent kinetic measurements for this molecule with OH radicals. In addition, the infrared absorption cross section is quantified between 400 and 4000 cm&lt;sup&gt;-1&lt;/sup&gt;, in an extended range of wavenumbers with respect to the previously reported ones&lt;sup&gt;5&lt;/sup&gt;. Combining each these observations, we are able to provide an improved estimate for the GWP of this molecule and its likely environmental fate.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;References:&lt;/p&gt;&lt;p&gt;&lt;span&gt;1. Ren, Y.; McGillen, M. R.; Da&amp;#235;le, V.; Casas, J.; Mellouki, A. Science Total Environ. &lt;/span&gt;&lt;strong&gt;2020&lt;/strong&gt;&lt;span&gt;, 749, 141406.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;2. Heathfield, A. E.; Anastasi, C.; Pagsberg, P.; McCulloch, A. Atmos. Environ. &lt;strong&gt;1998,&lt;/strong&gt; 32, 711&amp;#8211;717.&lt;/p&gt;&lt;p&gt;3. Papadimitriou, V. C.; Kambanis, K. G.; Lazarou, Y. G.; Papagiannakopoulos, P. J. Phys. Chem. A &lt;strong&gt;2004,&lt;/strong&gt; 108, 2666&amp;#8211;2674.&lt;/p&gt;&lt;p&gt;4. Bl&amp;#225;zquez, S.; Anti&amp;#241;olo, M.; Nielsen, O. J.; Albaladejo, J.; Jim&amp;#233;nez, E. Chem. Phys. Lett. &lt;strong&gt;2017&lt;/strong&gt;, 687, 297&amp;#8211;302.&lt;/p&gt;&lt;p&gt;5. Heathfield, A. E.; Anastasi, C.; McCulloch, A.; Nicolaisen, F. M. Atmos. Environ. &lt;strong&gt;1998&lt;/strong&gt;, 32, 2825&amp;#8211;2833.&lt;/p&gt;