Photostabilization polypropylene

Girois, S. Delprat, P. Audouin, L. Verdu, J. Oxidation thickness profiles during the photooxidation of non-photostabilized polypropylene. Polym. Degrad. Stab. 1997, 56, 169-177. 

Photodegradation of polyethylene waste can be markedly accelerated via its grafting with acrylamide [98], In contrast, photostabilization of polyethylene and polypropylene can be achieved as a result of the grafting of 2-hydroxy-4-(3-methacryloxy-2-hydroxy-propoxy) benzophenone using gamma radiation [ 147], In this case, the grafted compound acting as a U V stabilizer is chemically bound to the backbone chain of the polymer and its evaporation from the surface can be avoided. 

Hydroxyphenylbenzotriazoles have long been used as photostabilizers of polymers. For further details, see the 1990 review by Rabek photostabilizing mechanism of o-hydroxyphenylbenzotriazoles has been well investigated <87JPC1408). The absorption and fluorescence spectra of these photostabilizers have been the subjects of many publications (see Section 4.01.2.9). There are a great number of commercially available 2-(o-hydroxyphenyl)benzotriazoles. They have been widely used in the photostabilization of polypropylene, polystyrene, polyacrylates. 

In addition to acting as photostabilizers for polypropylene, nickel complexes also inhibit their direct thermal oxidative degradation by molecular oxygen. The salicylate complex (26), thought to be square planar, was more effective than the analogous cobalt(II) and copper(II) complexes.83 Iron(III) and chromium(II) analogues were almost inactive. Complexes (25) and (27) were roughly... 

Absorption Characteristics of Polypropylene. In discussions of the degradative effects of ultraviolet radiation, and photostabilization of polypropylene, absorption characteristics of the polymer as well as the energies involved should be considered. 

Al-Malaika, S. Desai, P. Scott, G. Mechanisms of antioxidant action photostabilization of polypropylene using dithiophosphoryl compounds— effects of alkyl substituents. Plast. Rubber Proces. Appl. 1985, 5 (1), 15-18. 

Photostabilization processes have not received much attention in the last year other than a multitude of review and specialist industrial articles. These include stabilization of polypropylene fibres, new stabilizer developments, sorting of stabilizers for polyethylene, trends in UV absorbers, hindered piperidines (hindered amine stabilizers (HAS)) for polyacrylics and urethanes, new stabilizers for polyolefins, enhanced service life applications, stabilizer mas-terbatches for polyester, stabilizers for UV cured acrylic overcoats for PVC, ° stabilization of clearcoats and various commercial packages. ... 

N.S. Allen, A. Chirinos-Padron, and J.H. Appleyard, Photostabilizing action of metal chelate stabilizers in polypropylene. Part VI. Importance of singlet ( A J oxygen quenching and UV screening, and flash photolysis studies, Polym. Degrad. Stab. 1984, 6, 31 15. 

N.S. Allen and J.F. McKellar, Photostabilization of commercial polypropylene by hindered piperidine compounds, Plast. Rubber Mat. Appl. 1979, 170-174. 

D J. Carlsson, K. Zhang, and D.M. Wiles, Polypropylene photostabilization by hindered amines in the presence of acidic species, J. Appl. Polym. Sci. 1987, 33, 875-884. 

The photostabilization of polymers continues to be a rapidly advancing area of scientific and technological interest. Carlsson and Wileshave written several reviews on photostabilizing mechanisms in polymers, while Swasey has given an updated guide to stabilization, and Reid has discussed the effects of stabilizers in vinyl polymers. Nemzek and Mayo have predicted the service life of polypropylene, and Bredereck has reviewed the photostabilization of PVC. Several comprehensive review articles have appeared. Pospisil has reviewed in considerable depth the photo-oxidation mechanisms of phenolic anti-oxidants, Shlyapintokh has reviewed the kinetics of stabilizer distribution, Vink has... 

Additives can also have a similar effect decabromo-diphenyl ether flame retardant in polypropylene was shown to enhance oxidation. Furthermore, where hindered-amine light stabilizers HALS were present in the compound, the degradation product HBr reacted with it to form the ammonium salt that has no photostabilizer effectiveness... 

Carlsson DJ, Chan KH, Wiles DM. Polypropylene photostabilization by tetramethylpiperi-dine species, no. 151. In Pappas SR, Winslow FH, editors. Photodegradation and photostabi-Usation of coatings. American Chemical Society Symposium Series 1981. p. 51-63. 

Allen NS, Chirinos-Padron A, Appleyard JH. The decomposition of cumene hydroperoxide by nickel(n) 2, 2 -thiobis(4-tert-octyl-phenolato)-n-butylamine (NI-1) in n-hexane solution and its possible importance in the photostabilization of polypropylene. Eur Polym J 1985 21 101-5. 

Stark, N.M., Mamana, L.M. Ultraviolet weathering of photostabilized wood-flour-filled high-density polyethylene composites. J. Appl. Polym. Sci. 90(10), 2609-2617 (2003) Bouza, R., Abad, M.J., Barral, L., et al. Efficacy of hindered amines in woodflour-polypropylene composites compatibilized with vinyltrimethoxysilane after accelerated weathering and moisture absorption. J. Appl. Polym. Sci. 120(4), 2017—2026 (2011)... 

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