Precision Vinyl Acetate/Ethylene (VAE) Copolymers by ROMP of Acetoxy-Substituted Cyclic Alkenes

Abstract

Tensile tests were conducted on a Rheometrics Scientific Minimat Instrument at a crosshead extension rate of 10 mm/min at room temperature. Dogbone samples (8 mm gage length, 0.5 mm gage thickness, 3 mm gage width) were prepared by stamping of compression molded film.Reported values are averages and standard deviations of four or five samples (see Figure S60 and S61).Wide-angle X-ray scattering (WAXS) measurements were performed on a Bruker D8 Discover diffractometer using a Cu Kα radiation point source. The data was collected and analyzed by Bruker GADDS software.Computational Methods. Calculation were performed at M06-2X/SDD|6-311+G(2df,p) // M06-L/SDD|6-31G(d) level of theory 3 with Gaussian 09 revision A.02. 4 Analytic frequency calculations were done for all structures in order to characterize their nature as either minima or TS structures, and also to compute thermal contributions to enthalpy and free energy. The effect of solvation by CHCl3 was computed from the SMD continuum solvation model. 5 Composite free energies in solution were computed by summing gas-phase M06-L thermal contributions with single point SMD/M06-2X single-point energies. Correction from the gas phase to the solution was made by adding -1.9 kcal/mol (RT Ln ([Sln]/[Gas])) to the free energy of each molecule.

Functionalized regio-regular linear polyethylenes from the ROMP of 3-substituted cyclooctenes

“…Treatment of 3-hydroxy-COE (9) [59] with thionyl chloride in the presence of pyridine gave 3-chloro-COE (10). The hydroxyl group in 9 was also oxidized to give 2-cyclooctenone (11).…”

“…We recently published a series of reports [55][56][57][58][59] demonstrating that single substitution at the 3-position (i.e., the allylic position) of cis-cyclooctene (COE) was an effective way to synthesize regio-and stereo-regular polyalkenamers by ROMP using the well-defined Grubbs second (G2) or third (G3) generation catalysts. Such substituents we have explored included hydrocarbon groups (3RCOE, R = methyl, ethyl, hexyl or phenyl) [55,56] and the acetoxy group [57][58][59].…”

“…Such substituents we have explored included hydrocarbon groups (3RCOE, R = methyl, ethyl, hexyl or phenyl) [55,56] and the acetoxy group [57][58][59]. All the reported polyalkenamers possess high levels ([95 %) of head-to-tail (HT) repeating unit connectivity and E double bond configuration.…”

Synthesis and utility of ethylene (meth)acrylate copolymers prepared by a tandem ring‐opening polymerization hydrogenation strategy

“…Polyethylene homopolymers for the control blend preparation were synthesized according to previously published procedure. 15 Molecular Characterization 1 H NMR and 13 C NMR spectra were recorded on Bruker AM-400, AV-500, AX-400, and Bruker HD-500 spectrometers using residual solvent peaks as internal standards; CDCl 3 , CF 3 COOD, and toluene-d 8 were used as the solvents.…”

“…The broad utility of this approach to materials useful for a wide variety of interesting applications has been clearly demonstrated in the literature. [2][3][4] The success of these approaches can be in large part attributed to the robust nature of ruthenium-based metathesis catalysts developed by Robert H. Grubbs and coworkers. [5][6][7] Indeed, these catalysts have been referred to by some as empyrean.…”