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Series: De Gruyter STEM
Methods and Technologies
Series: De Gruyter STEM
Series: De Gruyter STEM
Emerging Bio-Precursors for Chemical Processes
Series: De Gruyter STEM
Applications and Non-traditional Alternatives

Abstract

C14H12Br2O, monoclinic, C2 (no. 5), a = 29.7356(3) Å, b = 5.88712(4) Å, c = 11.10915(9) Å, β = 99.1700(8)°, V = 1919.88(3) Å3, Z = 6, R gt(F) = 0.0166, wR ref(F 2) = 0.0443, T = 100(2) K.

Abstract

C18H14N4O2, triclinic, P1̄ (no. 2), a = 7.6557(7) Å, b = 11.0905(8) Å, c = 11.3544(9) Å, α = 61.6430(10)°, β = 73.600(2)°, γ = 75.397(2)°, V = 805.86(11) Å3, Z = 2, R gt(F) = 0.0609, wR ref(F 2) = 0.1633, T = 298 K.

Abstract

The current measurement techniques described in the literature for the determination of the carbonyl index (CI) for polyolefins such as polyethylene and polypropylene were compared and contrasted. These were all found to be inconsistent or inaccurate and were not capable of differentiating significant changes in carbonyl peak evolution throughout accelerated ageing. As a consequence of these findings, a methodology, specified area under band (SAUB) is presented here to more accurately represent the CI as a general means of reporting. The increased precision in the methodology is explained and compared to other methodologies for determining CI. The SAUB method is also shown to be capable of elucidating the differences in relative extent and rates of CI for different polyolefins, exposed to the same conditions over the same time period.