High-temperature polymer polyether

Polyether imide. see High-temperature polymers Polyether sulfone. see High-temperature polymers Polyethylene terephthalate. see Polyester, thermoplastic... 

Further discussion on the general theme of high-temperature polymers and adhesives can be found in the articles entitled Polyphenylquinoxalines, Polybenzimidazoles and Polyether ether ketones. (See also article on High-temperature adhesives.)... 

Formed multilayer barrier packages, eg, trays, bowls, and cans from coextruded PP/PVDC/ PP, are being developed for soups and entrees that can be stored at ambient temperatures and heated to serving temperature in a microwave oven. Coextrusions of high performance, high temperature polymers, such as polyether-imide and polysulfone, for dual-oven containers capable of withstanding conventional bake-oven temperatures of 204-232°C are being tested. 

Papadimitriou KD, Geormezi M, Neophytides SG et al (2013) Covalent cross-linking in phosphoric acid of pyridine based aromatic polyethers bearing side double bonds for use in high temperature polymer electrolyte membrane fuel cells. J Membr Sci 433 1-9... 

Voege A, Deimede VA, Kallitsis JK (2012) Side chain crosslinking of aromatic polyethers for high temperature polymer electrolyte membrane fuel cell applications. J Polym Sci A Polym Chem 50 207-216... 

Kalamaras I, Daletou MK, Neophytides SG et al (2012) Thermal crosslinking of aromatic polyethers bearing pyridine groups for use as high temperature polymer electrolytes. J Membr Sci 415 16 42-50... 

Polyethers, polysulfones, polyterephthalamides and polysulfide polymers, and several other high temperature polymers are also part of this group, but they are still produced in low volumes. 

Polyester, thermoset. see Thermosets Polyester urethane 879 Polyether ether ketone, see High-temperature polymers... 

This chapter has provided a general summary of fatigue concepts, measurement techniques or methods, data presentation, and theory. It was meant to be introductory only and additional details should be obtained from the literature cited in this chapter [24-26], Chapters Styrenic Plastics, Polyether Plastics, Polyester Plastics, Polyimide Plastics, Polyamide Plastics (Nylons), Polyolefins and Acrylics, Thermoplastic Elastomers, Fluoropolymers, High-Temperature Polymers contain hundreds of plots of fatigue-related data on hundreds of different plastics. 

Gourdoupi, N. Daletou, M. Neophytides, S. Kallitsis, I, High temperature polymer electrolyte membranes and membrane electrode assemblies based on blends of aromatic polyethers. International Application WO 2008/032228 a2,... 

Pefkianakis, E. K. Morfopoulou, C. Deimede, V. Kallitsis, J. K., Blends of aromatic polyethers bearing polar pyridine units and their evalnation as high temperature polymer electrolytes, Macromol. Sympos., 219(1), 183-190 (2009). Deng, S. Mays, J. W. Hassan, M. K. Mauritz, K. A., Low cost high temperature fuel cell membranes based on poly(l,3-cyclohexadiene) homopolymers, polymer blends, and block copolymers, the 238th ACS National Meeting, ACS Division of Fuel Chemistry, Washington, DC, 16-20.08.2009. 

Materials similar ia high temperature properties to the Du Pont material with better low temperature properties have been synthesized usiag direct fluofination. The first was produced by reaction of fluorine with iaexpensive hydrocarbon polyethers such as poly(ethylene oxide). In the simplest case, poly(ethylene oxide) is converted to the perfluoroethylene oxide polymer ... 

Block copolymers can contain crystalline or amorphous hard blocks. Examples of crystalline block copolymers are polyurethanes (e.g. B.F. Goodrich s Estane line), polyether esters (e.g. Dupont s Hytrel polymers), polyether amides (e.g. Atofina s Pebax grades). Polyurethanes have enjoyed limited utility due to their relatively low thermal stability use temperatures must be kept below 275°F, due to the reversibility of the urethane linkage. Recently, polyurethanes with stability at 350°F for nearly 100 h have been claimed [2]. Polyether esters and polyether amides have been explored for PSA applications where their heat and plasticizer resistance is a benefit [3]. However, the high price of these materials and their multiblock architecture have limited their use. All of these crystalline block copolymers consist of multiblocks with relatively short, amorphous, polyether or polyester mid-blocks. Consequently they can not be diluted as extensively with tackifiers and diluents as styrenic triblock copolymers. Thereby it is more difficult to obtain strong, yet soft adhesives — the primary goals of adding rubber to hot melts. 

The presence of ether linkages in the polymer molecule imparts chain flexibility, lowers glass transition temperature, and enhances solubility while maintaining the desired high temperature characteristics [192]. Recently, polyether imines were prepared by the reaction of different diamines with 4,4 -[l,4-phenylene bis(oxy)] bisbenzaldehyde [184]. The polymers synthesized by the solution method were yellow to white in color and had inherent viscosities up to 0.59 dl/g in concentrated H2SO4. Some of these polyimines can be considered as... 

Much attention has been paid to the synthesis of fluorine-containing condensation polymers because of their unique properties (43) and different classes of polymers including polyethers, polyesters, polycarbonates, polyamides, polyurethanes, polyimides, polybenzimidazoles, and epoxy prepolymers containing pendent or backbone-incorporated bis-trifluoromethyl groups have been developed. These polymers exhibit promise as film formers, gas separation membranes, seals, soluble polymers, coatings, adhesives, and in other high temperature applications (103,104). Such polymers show increased solubility, glass-transition temperature, flame resistance, thermal stability, oxidation and environmental stability, decreased color, crystallinity, dielectric constant, and water absorption. 

In order to avoid these extremely dangerous phenomena, methods of treatment of PO with adsorbents (active carbon, charcoal, attapulgite, diatomaceous earth) were devised. By the treatment at room temperature of PO with these adsorbents (0.1-1% adsorbent in liquid PO), after a short contact time of about 15 minutes the high MW polyether is almost quantitatively retained by adsorption. The PO resulting after the filtration of the solid adsorbent is practically free of high MW polymers, and the polyethers obtained with the treated PO can be used to manufacture resilient flexible foams which will not collapse, with high rise and free of blow hole formation. 

Other polycondensation reactions which lead to finely dispersed polymers in liquid polyethers are the polycondensation reactions of urea and melamine with aqueous formaldehyde [92-95]. The reaction medium is usually polyether polyols, PO homopolymers or PO-EO copolymers (random or block copolymers), with MW of 3000-5000 daltons. During the polycondensation reaction, the aminoplast polymer precipitates, being insoluble in polyether and water (water from formaldehyde solution and reaction water), is eliminated by vacuum distillation. A variant of this reaction is to develop the polycondensation in water, and water containing the aminoplast polymer (as a viscous solution) is added to a polyether polyol, under vacuum, and at high temperature (100-130 °C), water being continuously eliminated from the reaction medium. The aminoplast insoluble polymer precipitates in the form of fine particles. 

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