Results 151 to 160 of about 1,621 (191)

Mechanism of protection of polymers by photostabilizers

Journal of Photochemistry and Photobiology A: Chemistry, 1991
Abstract Hydroxybenzotriazole and hydroxybenzophenone light stabilizers commonly used in polymers owe their photostability to fast, reversible proton transfer through their internal hydrogen bond and not to the quenching action of a low-energy triplet state.
Dimitri Noukakis, Paul Suppan
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Maleic diamides as photostabilizers for polystyrene

Journal of Industrial and Engineering Chemistry, 2013
Abstract Some condensation maleic diamide adducts were prepared, characterized, and evaluated as photostabilizers for polystyrene. The potency of these diamides was determined by measuring the extent of weight loss (%), formed gel as well as the average molecular weights M ¯ V of the soluble fractions of the degraded polymers.
Samira T. Rabie, Ahmed E. Ahmed, Magdy W. Sabaa, M.A. Abd El-Ghaffar   +3 more
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Complex formation in photostabilized polypropylene

Polymer Degradation and Stability, 1989
Abstract The formation of a yellow complex between 2-hydroxy-4-octoxybenzophenone and calcium stearate in the matrix of polypropylene has been observed. The same complex was prepared in model conditions and mixed into the polymer. In order to prevent colour changes in polypropylene, aliphatic or aromatic carboxylic acids were used as ‘harder’ ligands.
J. Bartuš, J. Beniska, V. Macho, M. Považancová   +3 more
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Utilization of Three Bark Extractives as Natural Photostabilizers for the Photostabilization of Wood Flour/Polypropylene Composites

Fibers and Polymers, 2020
Three kinds of tree bark extractives from trembling aspen (Populus tremuloides) (AE), lodgepole pine (Pinus contorta) (LE), and western red cedar (Thuja plicata) (RE) were produced and used as antioxidants. The antioxidation activities of those extractives were evaluated and compared with commercial antioxidant butylated hydroxytoluene (BHT).
Yao Peng, Ning Yan, Jinzhen Cao
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PHOTOSTABILIZATION OF MACROMOLECULES BY EXCITED STATE QUENCHING

Pure and Applied Chemistry, 1978
One approach to imparting long-term outdoor stability to polymeric systems is to add to them small amounts of compounds which will quench the electronic excitation energy associated with specific chromophores as a result of photon absorption. Carbonyl groups, hydroperoxides and singlet molecular oxygen (or its precursors) are chromophores commonly ...
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ChemInform Abstract: PHOTOSTABILE MODELLVERBINDUNGEN

Chemischer Informationsdienst, 1972
AbstractDie Kondensation des Äthantetraaldehyd‐Derivates (I) mit den Amidinen (II) inGegenwart vonÄthylat liefert die Bis‐pyrimidine (IIIa) und (IIIb).
J.‐E. OTTERSTEDT, R. PATER
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Photostabilization of photocrosslinked unsaturated polyesters

Polymer Degradation and Stability, 1994
Abstract The photo-oxidative stability of photocrosslinked unsaturated polyesters endcapped with glycidyl acrylate has been investigated by measuring UV, IR and ESCA spectra of thin films and tensile properties of photocrosslinked glass fiber laminates of the polyesters without and with added stabilizers.
Wenfang Shi, Baojun Qu, Bengt Rånby
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Mechanistic aspects of polymer photostabilization

Journal of Photochemistry and Photobiology A: Chemistry, 1989
Abstract A short account of modern theories in polymer degradation under oxidative conditions is followed by a detailed description of the different mechanistic aspects of polymer photostabilization. The discussion concentrates on the compounds presently known as photoantioxidants, which are believed to be the most efficient inhibitors of polymer ...
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Polymer photostabilization by surface grafting

Journal of Polymer Science: Polymer Symposia, 1976
AbstractVarious means by which photostabilization of polymers can be achieved are described, and work on a method of photostabilization by surface screening on a substrate polymer is presented. The surface screen is obtained by graft copolymerization of a polymerizable hydroxybenzophenone ultraviolet absorber.
P. J. Burchill, D. M. Pinkerton
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Some investigations on the photostabilization of polypropylene

Reaction Kinetics and Catalysis Letters, 1976
The effect of substituted hydroxybenzophenone, benzotriazole and organic metal complexes on the photooxidation of PP films has been studied. It has been established that NiDBTC added in 1.0 wt. % is the most effective photostabilizer.
G. Bálint, T. Kelen, Á. Rehák, F. Tüdős   +3 more
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