Interactions of the Hydroxylamine Derived from Bis-(2,2,6,6-tetramethyl-piperidinyl)-sebacate with Quinones.

Ohkatsu, Yasukazu; Yamacuchi, Kazuo; Sengoku, Tadashi; Sato, Tateki

doi:10.1627/jpi1958.37.405

Cited by 7 publications

(9 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this case, HALS NOH is found to show a higher synergism than HALS NH. This result coincides completely with the result obtained in the synergism between HALS and phenols 3) . Thus, UVA are regenerated by the action of HALS, even if UVA are eventually converted into a quinone due to the attack of peroxy radicals.…”

Section: Synergism In Photo-antioxidation Of Halssupporting

confidence: 91%

“…and UVA In the past, the synergism between HALS and phenols under UV light was explained by the regeneration of a phenol by the action of HALS on a quinone formed by the radical catching of a phenol (see Scheme 1) 3) . The quinone absorbs UV rays, and the resulting excited quinoid compound is reduced to a phenol by the action of HALS.…”

Section: Synergism In Photo-antioxidation Of Halsmentioning

confidence: 99%

“…Thus, an entirely new antagonism between HALS and phenols was proposed 2) . The HALS were developed as light stabilizers, but the decisive explanation, including a direct action on photo-antioxidant activities of HALS, has not been done except for the author s proposal 3) . A phenol catches peroxy radicals to be a quinone.…”

Section: Introductionmentioning

confidence: 99%

“…As a result, HALS seem to work as light stabilizer. This is only one photo-stabilizing mechanism explaining a synergism of HALS and phenols 3) . The HALS and ultraviolet absorbers (UVA) show synergism.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Interaction of Hindered Amine Light Stabilizers and Ultraviolet Absorbers

Takenaka

Mizokawa

Ohkatsu

2007

J. Jpn. Petrol. Inst.

Self Cite

View full text Add to dashboard Cite

The reason is discussed, why ultraviolet absorbers (UVA) having phenolic moiety show the synergism with HALS apparently, on the contrarily to phenolic antioxidants. A HALS nitrosonium is a substrate causing the useless oxidation of a phenol, and is formed from HALS more easily in the presence of a phenol. However, 2-hydroxybenzophenone (2-HBP) did not accelerate the formation of the nitrosonium so fast as 3,5-di-t-butyl-4-hydroxytoluene (BHT). A HALS nitrosonium, even if formed, did not oxidize 2-HBP so much as BHT. That is, 2-HBP can continue to work longer and more effi ciently in the presence of HALS. This fact suggests a weak antagonism of 2-HBP and a strong antagonism of BHT with HALS. On the other hand, quinones, derived from 2-HBP and BHT as result of peroxy radical-catching, were reduced to the corresponding hydroquinones by the action of HALS derivatives, such as HALS hydroxylamine. This reaction occurs strikingly faster and more easily for 2-HBP than for BHT. This fact shows a strong synergism of 2-HBP and a weak synergism of BHT with HALS. The above-mentioned results well explain the apparent synergism of UVA (2-HBP) with HALS, contrarily to the apparent antagonism of BHT with HALS.

show abstract

Section: Synergism In Photo-antioxidation Of Halssupporting

confidence: 91%

Section: Synergism In Photo-antioxidation Of Halsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Interaction of Hindered Amine Light Stabilizers and Ultraviolet Absorbers

Takenaka

Mizokawa

Ohkatsu

2007

J. Jpn. Petrol. Inst.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Group Affecting CHP Decomposition by HALS NH It has been reported so far that HALS and phenols are interacted with each other synergistically 15) or antagonistically 16) , depending on kinds of phenols, the mole ratio of HALS and phenols, and so on. On the other hand, almost all papers report that UVA are synergistic with HALS, although UVA have similar phenolic moieties.…”

Section: Physical Property Of the Phenolic Hydroxymentioning

confidence: 99%

Influence of Ultraviolet Absorbers on Decomposition of Hydroperoxide by Hindered Amine Light Stabilizers

Mizokawa

Ohkatsu

2007

J. Jpn. Petrol. Inst.

Self Cite

View full text Add to dashboard Cite

The interaction between hindered amine light stabilizers (HALS), and ultraviolet absorbers (UVA) was investigated, in order to clarify the reason why they generally show synergism, although UVA belong to kinds of phenols. A homolytic decomposition of cumene hydroperoxide (CHP) by amine-type HALS (HALS NH) in the presence of UVA is the antagonism bringing about autoxidation. This antagonism is found considerably weaker for UVA than that of 3,5-di-t-butyl-4-hydroxytoluene. This is based on a weak proton-donating ability of UVA to HALS due to their intramolecular hydrogen bond. Furthermore, a good relationship was found between the inhibition of photo-oxidation by UVA and the initial rate of homolytic decomposition of CHP by HALS in the presence of UVA, and a strong synergism of UVA with HALS was observed. As a result, UVA are able to exhibit an apparent synergism in a combination with HALS, because of no or little acceleration (antagonism) of homolytic hydroperoxide decomposition caused by the interaction with HALS, as well as the estimated regeneration (synergism) of new UVA from the corresponding quinoide-type compounds, even if formed, by the action of HALS or the derivatives.

show abstract

Preparation of a novel stabilizer and its thermal‐oxidative stabilization effect on polyamide 6

Xia

Shentu

Wang

2013

Polymer Engineering & Sci

View full text Add to dashboard Cite

A novel stabilizer containing hindered phenol and hindered amine light stabilizer (HALS) group in one molecule was prepared through the acyl chloride reaction followed by the amidation reaction. Its structure was characterized by electrospray ionization mass spectrometry (ESI‐MS) and proton nuclear magnetic resonance (1H‐NMR), Fourier transform infrared spectroscopy (FT‐IR). The thermogravimetric analysis (TGA) results under nitrogen and air atmosphere indicated that the addition of the novel stabilizer efficiently improved the thermal and thermal‐oxidative stability of polyamide 6 (PA6). The thermal‐oxidative stabilization effect of the novel stabilizer on PA6 was further evaluated in terms of reduced viscosity, tensile properties, and chemical structure after accelerated thermal aging in an air circulating oven at 150°C. The results indicated that the novel stabilizer could improve the thermal‐oxidative stability of PA6 effectively, resulting in the high retention of reduced viscosity and tensile strength, and the low ratio of terminal carboxyl group to amino group. The mechanism of the novel stabilizer on the thermal‐oxidative stabilization of PA6 was also discussed. POLYM. ENG. SCI., 54:2197–2206, 2014. © 2013 Society of Plastics Engineers

show abstract

Interactions of the Hydroxylamine Derived from Bis-(2,2,6,6-tetramethyl-piperidinyl)-sebacate with Quinones.

Cited by 7 publications

References 2 publications

Interaction of Hindered Amine Light Stabilizers and Ultraviolet Absorbers

Interaction of Hindered Amine Light Stabilizers and Ultraviolet Absorbers

Influence of Ultraviolet Absorbers on Decomposition of Hydroperoxide by Hindered Amine Light Stabilizers

Preparation of a novel stabilizer and its thermal‐oxidative stabilization effect on polyamide 6

Contact Info

Product

Resources

About