High temperature polymer blends applications

Wang YF, Hsu T, Hay AS, Li K, Patel B. High temperature polymer blends of poly(aryl ether ketone phthalazinone). US Patent Application 20110104417, assigned to Polymics Ltd., State College, PA 2011. 

Nowhere is that fact more apparent than in blends of liquid crystal polymers (LCPs) with other thermoplastic polymers. It is not the intent of the present chapter to completely review all the work done in the area of blends which contain LCPs. Instead, that will be the focus of Chapter 5. The objective of the present discussion is to make general observations and show how those general phenomena may be applicable to other high temperature polymer blends as well. 

Characterization of high temperature polymer blends for specific applications fuel cells and aerospace applications... 

Abstract This chapter examines the use of high temperature polymers as membranes, fuel cells and solar cells. Also, it considers the application of such materials for aerospace developments. The methods for characterization and testing of specific high temperature polymer blends for each of these applications are reviewed. 

High temperature polymer blends (HTPBs) for membrane applications... 

There do not appear to be any books devoted solely to high temperature polymer blends, let alone the thermodynamics of such mixtures. A reasonable review article of some of the factors that affect the phase behavior of polymer blends for high temperature applications was provided by Jaffe et al. ... 

Over the past 20 years a considerable chemical research effort was devoted to developing new high temperature polymers. It is interesting to note that some of these materials are now finding new applications and solutions to old problems of processing through blending. A commercial series of products trade-named Tribolon XT has been announced which are based on an aromatic polymide (Upjohn s 2080) with Phillips poly(phenylene sulfide), trade-named Ryton. A recent publication (88) describes some of the unique characteristics of this new family of materials. 

FKMs are coextruded with lower-cost copolymers such as etliylene acrylic copolymer. They can be modihed by blending and vulcanizing with other synthetic rubbers such as silicones, ethylene propylene rubber (EPR) and ethylene propylene diene monomer (EPDM) rubbers, epichlorohydrin, and nitriles. Fluoroelastomers are blended with modihed nitrile butadiene rubber (NBR) to obtain an intermediate performance-cost balance. These blends are useful for underhood applications in environments outside the engine temperature zone such as timing chain tensioner seals. Fluoroelastomers can also be blended with fluorosilicones and other high-temperature polymers to meet engine compartment environments and cost-performance balance. 

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,... 

Key words polybenzimidazole, high performance polymer blend, high temperature applications. 

Polycarbonates based on tetramethylbisphenol A are thermally stable and have a high Vicat softening point of 196°C. On the other hand they have lower impact and notched impact resistance than the normal polymer. Blends with styrene-based polymers were introduced in 1980, and compared with PC/ABS blends, are claimed to have improved hydrolytic resistance, lower density and higher heat deflection temperatures. Suggested applications are as dishes for microwave ovens and car headlamp reflectors. 

Because of increased production and the lower cost of raw material, thermoplastic elastomeric materials are a significant and growing part of the total polymers market. World consumption in 1995 is estimated to approach 1,000,000 metric tons (3). However, because the melt to solid transition is reversible, some properties of thermoplastic elastomers, eg, compression set, solvent resistance, and resistance to deformation at high temperatures, are usually not as good as those of the conventional vulcanized mbbers. Applications of thermoplastic elastomers are, therefore, in areas where these properties are less important, eg, footwear, wire insulation, adhesives, polymer blending, and not in areas such as automobile tires. 

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