ISSN:
0003-3146
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Thermoplastics are currently receiving considerable attention for potential use as structural resins in aerospace vehicles. These materials offer an attractive combination of chemical, physical and mechanical properties. Perhaps the most important advantage offered by the thermoplastics over the new toughened thermosets in composite applications is the potential of low cost manufacturing. However, many problems must be resolved with the thermoplastics before they find extensive use in aerospace composite applications. As part of an effort on improved thermoplastics for use as structural resins, NASA Langley Research Center has been intimately involved in research on polyimides, polyarylene ethers, and polyphenylquinoxalines. Several new semi-crystalline polyimides with high adhesive properties [e.g. Ti/Ti tensile shear strength @ 25°C of 54.1 MPa] and high fracture energies (GIc) [e.g. 6600 J/M2] are under evaluation. New polyarylene ethers offer glass transition temperatures ranging from 114 to 280°C, crystalline melt temperatures of 275 to 400°C, fracture energies (GIc) as high as 6300 J/M2, and good processability. Ethynyl groups were placed on the ends of arylene ether oligomers and subsequently cured to provide materials with excellent adhesive properties and solvent resistance. In the polyphenyl-quinoxaline family, various new homo, co and crosslink polymers display improved processability, good mechanical properties, and higher use temperature. The chemistry (structure/property relationships), mechanical and physical properties of these new thermoplastics are discussed herein.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/apmc.1986.051450116
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