Thermal oxidative degradation and ageing performance of silicone rubber filled with attapulgite

AbstractAn oil-soluble antioxidant, alkylated diphenylamine (ADPA), was prepared by alkylation of diphenylamine. The influence of ADPA on the thermal-oxidative stability of poly-α-olefin (PAO8) was evaluated by thermogravimetry (TG). For comparison, the thermal-oxidative stability of PAO8 with zinc dialkyl dithiophosphate (ZDDP) was also investigated. Activation energy (E

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Thermal and thermal-oxidative degradation of polycyanates

Polymer Science U S S R ◽

10.1016/0032-3950(74)90111-7 ◽

1974 ◽

Vol 16 (1) ◽

pp. 15-23 ◽

Cited By ~ 6

Author(s):

V.V. Korshak ◽

P.N. Gribkova ◽

A.V. Dmitrenko ◽

A.G. Puchin ◽

V.A. Pankratov ◽

...

Keyword(s):

Oxidative Degradation ◽

Thermal Oxidative Degradation

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Catalytic action of metallic salts in autoxidation and polymerization. V. Effect of some cobaltic compounds on the thermal oxidative degradation of isotactic polypropylene

Journal of Polymer Science Part B Polymer Letters ◽

10.1002/pol.1971.110090705 ◽

1971 ◽

Vol 9 (7) ◽

pp. 497-502 ◽

Cited By ~ 13

Author(s):

Zenjiro Osawa ◽

Takashi Ishizuka ◽

Masami Sorimachi ◽

Yoshitaka Ogiwara

Keyword(s):

Isotactic Polypropylene ◽

Oxidative Degradation ◽

Catalytic Action ◽

Thermal Oxidative Degradation ◽

Metallic Salts

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Effect of char layer on transient thermal oxidative degradation of polyethylene

Thermal Science ◽

10.2298/tsci0702023e ◽

2007 ◽

Vol 11 (2) ◽

pp. 23-36 ◽

Cited By ~ 1

Author(s):

Javad Esfahani ◽

Ali Abdolabadi

Keyword(s):

Heat Transfer ◽

Heat Source ◽

Solid Phase ◽

Early Stage ◽

Radiation Heat Transfer ◽

Oxidative Degradation ◽

Degradation Process ◽

Thermal Oxidative Degradation ◽

Char Layer ◽

Effect Of Oxygen

A transient one dimensional model has been presented to simulate degradation and gasification of polyethylene, in early stage of fire growth. In the present model effect of oxygen on degradation and rate of polymer gasification while the sample is subjected to an external radiative heat source is numerically investigated. This model includes different mechanism, which affect the degradation process, such as in depth thermal oxidative decomposition, in depth absorption of radiation, heat transfer, volatiles advection in solid phase and convective heat transfer on surface. Also effects of radiative parameters, due to formation of char layer such as surface reflectivity and absorptivity on thermal degradation of polyethylene are investigated. The results for 40 kW/m2 heat source are reported and yielded realistic results, comparing to the published experimental data. The results show that an increase in oxygen concentration leads to considerable increase in gasification rate and also leads to sharp increase of surface temperature. .

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Influence of Crosslink Characteristics Induced by Aromatic-Based Antioxidants on the Swelling and Stress-Strain Behavior of Natural Rubber Vulcanizates

Rubber Chemistry and Technology ◽

10.5254/1.3547747 ◽

2003 ◽

Vol 76 (2) ◽

pp. 334-347 ◽

Cited By ~ 1

Author(s):

Tarek M. Madkour ◽

Rasha A. Azzam

Keyword(s):

Natural Rubber ◽

Crosslinking Agent ◽

Oxidative Degradation ◽

Thermal Oxidative Degradation ◽

Stress Strain ◽

Strain Behavior ◽

Strain Induced Crystallization ◽

Elastomeric Chains ◽

Natural Rubber Vulcanizates ◽

Induced Crystallization

Abstract Stress-strain measurements were performed on dry and swollen natural rubber vulcanizates prepared using both sulfur as the crosslinking agent and aromatic-based bound antioxidants acting as a second crosslinking agent. The aromatic-based antioxidants were synthesized and analyzed spectroscopically in order to relate the final behavior of the vulcanizates to the nature of the crosslink characteristics. The anomalous upturn in the modulus values of these networks in response to the imposed stress was shown to persist in the dry as well as the swollen state. Since the swollen elastomeric chains cannot undergo a strain-induced crystallization, the abnormal upturns in the modulus values in an absence of a filler were explained on the basis of the limited extensibility of the short chains of networks prepared using two different crosslinking agents in line with earlier modeling predictions. Remarkably, the swelling experiments revealed the increase in the crosslink density of the networks in the early stages of the thermal oxidative degradation procedure indicating a post-cure of the chemically bound antioxidants to the elastomeric chains, which incidentally corresponds to a maximum in the modulus values of the networks. The rheological and other mechanical properties such as the hardness were shown not to have been affected as a result of the incorporation of the chemically bound antioxidants.

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