Tinuvin 2- benzotriazole

The photodegradation of synthetic polymers can be considerably reduced upon addition of ultraviolet stabilizers. The UV stabilizers (preferably derivatives of o-hydroxy-benzophenone or of 2-(2 -hydroxys -methylphenyl)benzotriazole (Tinuvin) transform the absorbed light energy into thermal energy thus preventing all sorts of photochemically initiated reactions. For review articles see the papers of Otter-stedt (.l), Heller and Blattmann ( 2, 2), Kloepffer (jl, j ), Gysling (JS) and Trozzolo (19 ) ... 

In contrast, the second UV-sorber, this time a benzotriazole, Tinuvin 327 introduced into Set B, was not effective when used alone (27.9% S.R., even less than the control), and it even reduced the effectiveness of one of the two HALS used (Tinuvin 765, from 71% S.R. when used alone to 54.3%). 

Light stabiUzers 2-(2 -hydroxy-3,3,5-di-tert-amylphenyl)benzotriazole Tinuvin 328... 

In the following we discuss the spectral signatures observed by ultrafast absorption spectroscopy of ESIPT molecules with a time resolution sufScient to temporally resolve the nuclear motions during the transfer. Pioneering work was performed on 2-(2 -hydroxy-5 -methylphenyl)benzotriazole (TINUVIN P), and for the first time oscillatory signal contributions associated with the ESIPT were observed [26]. 

Bumelrizole-, 2-(3,5 Di-t-butyl-2 bydroxypbenyl)-S-chlorobenzotrlazoler, Givsorb UV-2 2-(2 -Hydroxy-3,5 -di-t-amyipbenyi) benzotriazole, Tinuvin 326 Tinuvin 327 Tinuvin 328 Tinuvin 571 Tinuvin P UV absorber, polyphenylene Tinuvin 327... 

Tinuvin 234. See 2-[2-Hydroxy-3,5-di-(1,1-dimethylbenzyl) phenyl]-2H-benzotriazole Tinuvin 326. See Bumetrizole Tinuvin 327. See 2-(3, 5 -Di-t-butyl-2 -hydroxyphenyl)-5-chlorobenzotriazole Tinuvin 328. See 2-(2 -Hydroxy-3,5 -di-t-amylphenyl) benzotriazole Tinuvin 329. See Octrizole Tinuvin 571. See Phenol, 2-(2H-benzotriazole-2-yl)-4-methyl-6-dodecyl Tinuvin 622, Tinuvin 622LD. See Dimethylsuccinate/tetramethyl hydroxy-1 -hydroxyethyl piperidine polymer Tinuvin 765. See Bis (1,2,2,6,6-pentamethyl-4-pipehdinyl) sebacate... 

General Electric [53] claimed the use of 2(2"-hydroxy-3, 5 -di- -amylphenyl)benzotriazole (Tinuvin 328 Ciba) for UV stabilisation of fire-retarded PET formulations. Adeka Argus [54] patented alkylidene-bis(benzotriazolylphenols) such as 2,2 -methylene-bis(4-methyl-6-benzotriazolylphenol) for use in aromatic polyesters, later commercialised as ADK Stab LA31. Heat-shrinkable polyester films... 

Contact allergies to UV-light absorbers like 2-hydroxybenzophenone, resorcinol monobenzoate, 2-(2-hydroxy-5-methylphenyl)benzotriazole (Tinuvin P) and bis-(2,2,6,6)-tetramethyl-4-piperidyl-sebacate have been encountered [14-16]. Organic pigments, mostly of the azo types, are potentially sensitizing additives in plastics [17,18]. 

Phenol, 2-(5-chloro-2H-benzotriazole- Tinuvin 327 (Ciba Specialty 2-yl)-4,6-bis(l,l-dimethylethyl)- Chemical) Lowilite 27 (Great... 

Di-rerr-butyl-2 -hy-droxyphenyl)-5-chloro-benzotriazol (Tinuvin 327)... 

Table 3.4 Influence of stabilization on polystyrene disooloration (injection molded plates, 2 mm) during exposure in the weatherometer WRC 600 AO n-ootadecyi-3-(3 , 5 -di-tert-butyt4 -hydroxy-phenyljpropionate (IRGANOX 1076), UVA 2-(2,2 -hydroxy-5 -methyl-phenyl)benzotriazole (TINUVIN P), HALS sebacic aoid bis-2,2,6,6 tetramethyt-4-piperidylester (TINUVIN 770) [86]...

Already in early investigations transfer times of about 100 fs or less were observed for HBT in tetrachloroethylene [7], 2-(2 -hydroxyphenyl)benzoxazole (HBO) in cyclohexane [33], and for methyl salicylate (MS) [34] and OH BA [35] in gas phase. For a number of ESIPT molecules, very fast transfer times were found even at cryogenic temperatures [36]. Pioneering work was performed on 2-(2 -hydroxy-5 -methylphenyl)benzotriazole (TINUVIN P), and for the first time oscillatory signal contributions associated with the ESIPT were observed [37]. Meanwhile ultrafast ESIPT and subsequent signal oscillations due to coherent wavepacket motions were also found in HBO [38], OHBA [39], and a number of other ESIPT compounds [13, 40-43]. 

An interesting tautomerism occurs in benzotriazoles (TINUVIN) that are used as light filters in dye protection. The tautomerism processes in porphyrins are the basis of a photochromic reaction used in hole burning.This process has been used for making a molecular computer. Dithizonates were used as photochromic materials in ophthalmic lenses. ... 

LC-tandem MS was recently used for polymer/additive characterisation. In cases of soft ionisation processes (e.g. ESI, APCI, etc.), MS/MS is often necessary to confirm the ionic species. QITMS has the potential to improve the detection limits for organotin analysis compared to QMS. HPLC-UV and LC-API-MS/MS have been employed for the characterisation of the products of photodegradation of benzotriazole-based UV absorbers (Tinuvin P/328/900) under mild conditions [642]. Among the photoproducts identified... 

Figure 8.10 Solid-state stmcture of Tinuvin 928 [2-(2 -hydroxy-5 -tert-octylphenyl)benzotriazole]. After DeBillis et al. [336]. Reprinted with permission from A.D. DeBellis et al., ACS Symposium Series, 805, 453-467. Copyright (2002), American Chemical Society...

UV irradiation of 2-arylbenzotriazoles (144), including the commercially available photostabilizer Tinuvin P, in an aerated solvent results in oxidation of the benzo ring to give the 2-aryl-l,2,3-triazole-4,5-dicarboxylic acid (146), possibly via the intermediate 2-arylbenzotriazole-4,7-dione (145) (Scheme 25). Indeed, when the independently synthesized l-phenyl-2. -benzotriazole-4,7-dione (145, R = = H) is irradiated under the same conditions, compound (146 R = R = H) is formed, and... 

Tinuvin 327 (benzotriazole) Ciba-Geigy Corp. 2-(3, 5 -di-tert-butyl-2 -hydroxyphenyl)-5-chlorobenzot riazole... 

Set B Based on the results of set A discussed below, a third set. Set B, was prepared (Table IV). Cyasorb 531 (a benzophenone UV light absorber) was found to be the most effective stabilizer in Set A. It was therefore rerun at an even lower add-on in Set B, and since it was the only UV light absorber included in Set A, a second type of UV absorber, Tinuvin 327 (a benzotriazole) was included in Set B. Two new non-polymeric hindered amine light stabilizers (HALS) Tinuvin 770 and Tinuvin 765 were also evaluated in Set B with the hope that they might be more effective than the polymeric HALS (Chimassorb 944LD) included in Set A which was quite detrimental to the heat stability. Combinations of these four additives were also applied in Set B. The three new compounds evaluated have been reported to be effective light stabilizers for polyester and polyamide fibers (Capocci, G., Ciba Geigy Corporation, Ardsley, NY, personal communication, 1986). 

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