Die Kinetik und Mechanismus der direkten Fluorinierung von Polyethylenen

Kharitonov, A. P.; Taege, R.; Ferrier, G.; Piven, N. P.

doi:10.1007/bf02699574

Cited by 43 publications

(85 citation statements)

References 22 publications

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“…It also plays an auxo-action for generation of C=O containing groups. Besides, the formation of C=O containing groups may be accompanied by scission of main polymer molecular chain, 12 leading to thermal-oxidative aging of LDPE molecules. It is proved by the measured thermal decomposition energy of fluorinated samples in figure 2.…”

Section: Resultsmentioning

confidence: 99%

“…On the one hand, it supplies more radicals to initiate the above O 2 relevant reactions because F 2 is easier to react with LDPE molecules, generating radicals like F • , -CH • -and -CF • -, etc. 12,13 So generating processes of ROOH or RO 2 • are accelerated, which is helpful for generation of C=O containing groups. At the same time, direct fluorination can provide F atoms or fluoroalkyl radicals for formation of -C(O)F groups, which will be hydrolyzed through the activity of moisture into -C(O)OH groups by reaction -C(O)F + H 2 O → -C(O)OH + HF.…”

Section: Resultsmentioning

confidence: 99%

“…It is consistent with all the previous researches on direct fluorination. [7][8][9]12,13 Introduced F atoms are believed to replace the H atoms in LDPE molecular chain by a radical process. 12 The process initiates by reaction between F 2 and -CH 2 -group, and terminates with generation of -CF x groups (such as -CHF-, -CF 2 -and -CF 3 ).…”

Section: Resultsmentioning

confidence: 99%

“…Based on the earlier analysis about the constitutes evolution in surface fluorinated layer, it is easy to find that the dipoles should be the C=O containing groups and some of the -CF x groups, such as -C(O)F, -C(O)OH, -CHF-and -CF 3 , etc. 12,13 The polarization relaxation of the dipoles should be the main reason for the permittivity increase of the surface fluorinated layer in figure 3(a). Besides, ε r -FL-0.1 and ε r -FL-1.0, the permittivity of the surface fluorinated layer at both 0.1 Hz and 1.0 Hz (relatively close to DC), increase with fluorinating pressure increasing in the embedded figure in figure 3(a).…”

Section: B Effect Of Fluorine and Oxygen On Dielectric Properties Ofmentioning

confidence: 99%

“…Because the properties of bulk LDPE are thought unchanged due to the tiny thickness of surface fluorinated layer. 9,12 For quantitatively calculating the permittivity and the conductivity of surface fluorinated layer, the fluorinated sample is equalized as a RC analog circuit in figure 4. Then the reactance of fluorinated sample is, namely, 1…”

Section: B Effect Of Fluorine and Oxygen On Dielectric Properties Ofmentioning

confidence: 99%

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Space charge characteristics of fluorinated polyethylene: Different effects of fluorine and oxygen

Zhao

Nie

2018

AIP Advances

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Direct fluorination are proved having obvious effect on space charge characteristics of polyethylene. It is believed that fluorine has a positive effect on suppressing space charge injection while oxygen impurity has a negative effect. However, the mechanism for the opposite effect of fluorine and oxygen is still not clear. In this paper, the different effects of fluorine and oxygen on space charge characteristics of fluorinated low density polyethylene (LDPE) are investigated on the basis of dielectric property, chemical constitutes and trap performance of surface fluorinated layers. The results show that direct fluorination has obvious effect on chemical constitutes and dielectric properties of surface fluorinated layer. Introduced fluorine is the main factor for suppressing charge injection from the electrodes, because it seriously changes the chemical constitutes and further the trap properties of the surface fluorinated layer. While introduction of oxygen results in heterocharges and makes space charge distribution complex, due to the ionization of generated small groups like C=O containing groups. Moreover, direct fluorination will result in cleavage of some LDPE molecules whatever there is oxygen impurity or not.

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: B Effect Of Fluorine and Oxygen On Dielectric Properties Ofmentioning

confidence: 99%

Section: B Effect Of Fluorine and Oxygen On Dielectric Properties Ofmentioning

confidence: 99%

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Space charge characteristics of fluorinated polyethylene: Different effects of fluorine and oxygen

Zhao

Nie

2018

AIP Advances

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Improved efficacy of α‐particle–targeted radiation therapy

Milenic

Brady

Garmestani

et al. 2010

Cancer

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BACKGROUND Human epidermal growth factor receptor–2 (HER-2) and tumor-associated glycoprotein 72 (TAG-72) have proven to be excellent molecular targets for cancer imaging and therapy. Trastuzumab, which binds to HER-2, is effective in the treatment of disseminated intraperitoneal disease when labeled with 213Bi or 212Pb. 213Bi-humanized CC49 monoclonal antibody (HuCC49ΔCH2), which binds to TAG-72, inhibits the growth of subcutaneous xenografts. A next logical step to improve therapeutic benefit would be to target tumors with both molecules simultaneously. METHODS Athymic mice bearing intraperitoneal human colon carcinoma xenografts were treated with a combination of trastuzumab and HuCC49ΔCH2 labeled with 213Bi administered through an intraperitoneal route. The sequence of administration also was examined. RESULTS Before combining the 2 monoclonal antibodies, the effective doses of 213Bi-CC49ΔCH2 and 213Bi-trastuzumab for the treatment of peritoneal disease were determined to be 500 μCi for each labeled antibody. Treatment with 213Bi-HuCC49ΔCH2 resulted in a median survival of 45 days and was comparable to the median survival achieved with 213Bi-trastuzumab. Each combination provided greater therapeutic efficacy than either of the agents given alone. However, the greatest therapeutic benefit was achieved when 213Bi-HuCC49ΔCH2 and 213Bi-trastuzumab were coinjected, and a median survival of 147 days was obtained. CONCLUSIONS Dual targeting of 2 distinct molecules in tumors such as TAG-72 and HER-2 with α-particle radiation resulted in an enhanced, additive, therapeutic benefit. The authors also observed that this radioimmunotherapeutic strategy was well tolerated.

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Modification of ultra‐high‐molecular weight polyethylene by various fluorinating routes

Kharitonov

Симбирцева

Bouznik

et al. 2011

J. Polym. Sci. A Polym. Chem.

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Chemical–physical properties of ultra‐high‐molecular weight polyethylene (UHMWPE) treated by direct fluorination, direct fluorination accompanied with UV irradiation, by XeF2 and by TbF4, were tested by FTIR spectroscopy, visible spectroscopy, 19F and 13C NMR, scanning electron microscopy, XRD, and EPR. Surface energy measurements were carried out. The direct fluorination of UHMWPE is a diffusion‐controlled process, but treatment with XeF2 is a kinetically controlled one. Direct fluorination and direct fluorination accompanied with UV irradiation results mainly in a formation of CF2 groups. On the contrary, CHF groups are prevailing in UHMWPE treated with XeF2 and TbF4. Surface texture of UHMWPE treated with XeF2 and with F2 is quite different. Direct fluorination results in a higher polarity of the polymer surface when compared with treatment with XeF2. For the case of direct fluorination, both long‐lived peroxy and fluoroalkylradicals are formed. For the case of treatment with XeF2, only fluoroalkylradicals were detected. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49:3559–3573, 2011

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Die Kinetik und Mechanismus der direkten Fluorinierung von Polyethylenen

Cited by 43 publications

References 22 publications

Space charge characteristics of fluorinated polyethylene: Different effects of fluorine and oxygen

Space charge characteristics of fluorinated polyethylene: Different effects of fluorine and oxygen

Improved efficacy of α‐particle–targeted radiation therapy

Modification of ultra‐high‐molecular weight polyethylene by various fluorinating routes

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