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Polymer Bulletin, Mar 29, 1999
ABSTRACT Summary PVC stabilised with mixtures of pre-heated metal stearates are degraded thermall... more ABSTRACT Summary PVC stabilised with mixtures of pre-heated metal stearates are degraded thermally for specific periods of time, in order to determine their influence on the production of polyenes by uv spectroscopy. Additionally, the PVC samples are treated with NaBH4 to reduce the carbonylic groups produced during the thermo-oxidative process. Important differences in the polyene formation trends are observed, between the reduced and non-reduced samples, indicating that the carbonyl groups attached to polyenes shift the absorbance maxima and alter considerably the quantification of the double bond conjugations.
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Metal Finishing, 1997
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Polymer, 1985
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Comprehensive Polymer Science and Supplements, 1989
Pigments and dyes are widely used in the colouration of polymer materials for many commercial app... more Pigments and dyes are widely used in the colouration of polymer materials for many commercial applications.1 Although they are primarily used to impart colour to the particular polymer and make it attractive to the consumer, except for uses where colour coding is important, pigments and dyes can have a dramatic effect on photostability.2–4 For example, by absorbing and/or screening UV light, pigments can induce a marked protective effect. However, a number of dyes and pigments may also be photoactive and can, therefore, catalyze or accelerate the photochemical breakdown of the polymer. In this section the photostability of the polymer as influenced by the presence of dyes and pigments will be the main directive rather than the stability of the colourant itself. For further information on the latter subject the reader is directed elsewhere.2 It is important to note that in many applications the presence of dyes and pigments can dramatically influence the chemistry of the degradation, oxidation and stabilization processes involved in a polymer and will quite often dominate the overall practical stability of the end-product.5
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Polymer Photochemistry, 1986
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Polymer Photochemistry, 1984
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Polymer Photochemistry, 1983
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Polymer Photochemistry, 1986
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Polymer Degradation and Stability, 1980
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Polymer Degradation and Stability, 1980
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Polymer Degradation and Stability, 1984
Abstract Further novel observations are reported on the nature of the hexane extractable fluoresc... more Abstract Further novel observations are reported on the nature of the hexane extractable fluorescent species in four polyolefins, namely low and high density polyethylene, polypropylene and poly (4-methylpent-1-ene). The concentration of fluorescent species ...
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Journal of Photochemistry and Photobiology A: Chemistry, 1988
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Journal of Photochemistry and Photobiology A: Chemistry, 1988
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Dyes and Pigments, 1992
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Polymer Photochemistry, 1986
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SSRN Electronic Journal
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Polymer Degradation and Stability, 2021
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Polymer Degradation and Stability, 2018
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Polymer Bulletin, Mar 29, 1999
ABSTRACT Summary PVC stabilised with mixtures of pre-heated metal stearates are degraded thermall... more ABSTRACT Summary PVC stabilised with mixtures of pre-heated metal stearates are degraded thermally for specific periods of time, in order to determine their influence on the production of polyenes by uv spectroscopy. Additionally, the PVC samples are treated with NaBH4 to reduce the carbonylic groups produced during the thermo-oxidative process. Important differences in the polyene formation trends are observed, between the reduced and non-reduced samples, indicating that the carbonyl groups attached to polyenes shift the absorbance maxima and alter considerably the quantification of the double bond conjugations.
Bookmarks Related papers MentionsView impact
Metal Finishing, 1997
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Polymer, 1985
Bookmarks Related papers MentionsView impact
Comprehensive Polymer Science and Supplements, 1989
Pigments and dyes are widely used in the colouration of polymer materials for many commercial app... more Pigments and dyes are widely used in the colouration of polymer materials for many commercial applications.1 Although they are primarily used to impart colour to the particular polymer and make it attractive to the consumer, except for uses where colour coding is important, pigments and dyes can have a dramatic effect on photostability.2–4 For example, by absorbing and/or screening UV light, pigments can induce a marked protective effect. However, a number of dyes and pigments may also be photoactive and can, therefore, catalyze or accelerate the photochemical breakdown of the polymer. In this section the photostability of the polymer as influenced by the presence of dyes and pigments will be the main directive rather than the stability of the colourant itself. For further information on the latter subject the reader is directed elsewhere.2 It is important to note that in many applications the presence of dyes and pigments can dramatically influence the chemistry of the degradation, oxidation and stabilization processes involved in a polymer and will quite often dominate the overall practical stability of the end-product.5
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Polymer Photochemistry, 1986
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Polymer Photochemistry, 1984
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Polymer Photochemistry, 1983
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Polymer Photochemistry, 1986
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Polymer Degradation and Stability, 1980
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Polymer Degradation and Stability, 1980
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Polymer Degradation and Stability, 1984
Abstract Further novel observations are reported on the nature of the hexane extractable fluoresc... more Abstract Further novel observations are reported on the nature of the hexane extractable fluorescent species in four polyolefins, namely low and high density polyethylene, polypropylene and poly (4-methylpent-1-ene). The concentration of fluorescent species ...
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Journal of Photochemistry and Photobiology A: Chemistry, 1988
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Journal of Photochemistry and Photobiology A: Chemistry, 1988
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Dyes and Pigments, 1992
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Polymer Photochemistry, 1986
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SSRN Electronic Journal
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Polymer Degradation and Stability, 2021
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Polymer Degradation and Stability, 2018
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