Poly radiation resistance

LEWIS ETAL. Radiation-Resistant Poly (arylene ether sulfones)... 

Polymeric pattern Polymerization Radiation resist Poly(alkylthienylene vinylene) Poly(3-methoxythienylene vinylene)... 

A substantial intramolecular protective effect by phenyl groups in polymers is shown by the low G values for Hz and crosslinking in polystyrene (substituent phenyl) and in polyarylene sulfones (backbone phenyl), as well as many other aromatic polymers. The relative radiation resistance of different aromatic groups in polymers has not been extensively studied, but appears to be similar, except that biphenyl provides increased protection. Studies on various poly(amino acid)s indicate that the phenol group is particularly radiation resistant. 

Ito, C.G. Willson, and J.M.J. Frechet, New UV resists with negative orpositive tone, Digest of Technical Papers, 1982 SPE Symp. on VLSI Technology, p. 6 (1982) C.G. Willson, H. Ito, J.M.J. Frechet, T.G. Tessier, and F.M. Houlihan, Approaches toward the design of radiation sensitive poly meric imaging systems with improved sensitivity and resolution, J. Electrochem. Soc. 133, 181 (1986). 

Beside inhibiting thermooxidative ageing, phosphorus containing additives increase radiation resistance of polyimides and poly(alkyl terephthalates) the rate of evolution of the aromatic ring radiation degradation product - CH4 reduces two-fold. 

Lee et al. have irradiated different immiscible blends of poly(phenylene oxide) and poly(2-vinylnaphtalene). The objective of this work was to check if the latter polymer could improve the radiation resistance of the former. On the basis of thermal stability, mechanical properties and light resistance, no protective effect of poly(2-vinylnaphtalene) could be confirmed. 

The radiation resistance for a series of polyimides(PI), poly(aryl ether ether ketone) (PEEK), poly(aryl ether sul-phone) (PES), bisphenol A type Udel poly(aryl sulphone) (U-PS), and a poly(aryl ester) (U-Polymer) is shown to be excellent when compared to the related aliphatic polymers. G values for the evolution of gases were lower by factors of between 0.01 and 0.001 of the G values for the corresponding aliphatic polymers. From the study of gas evolution, the order of radiation resistance to 7-irradiati(Mi is [186] ... 

Poly(phenylmethylsiloxane) Si-0- CeHsCH3 Suppressed crystallinity and improved radiation resistance... 

The various materials (often polymers) have to be chosen such that they are sufficiently radiation resistant to withstand the sterilization dose. Under the dose conditions, needed for sterilization some polymers such as polyethylene, polystyrene, poly(ethylene terephthalate), polyurethanes, and epoxides maybe stable, whereas others such as polypropylene, poly(methyl methacrylate), polyvinyl chloride (PVC) may not. When the radiation stability of the plastic... 

Tiwari VK, KuMya PK, Avasthi DK, Maiti P. Radiation-resistant behavior of poly-(vinyUdene lluoride)/layered sdicate nanocomposites. ACS Appl Mater Interfaces December 2009 1(2) 311-8. 

Less radiation resistant flexible chain polymers that have been studied by HREM include iPS [96], PTFE [97, 98], PE [99, 100], poly(/ -hydro-xybutyrate) [101], poly(p-phenylene sulphide)... 

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