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phosphorus-containing imide resins - modification by elastomersThe syntheses and general features of addition-type maleimide resins based on bis(m-aminophenyl)phosphine oxide and tris(m-aminophenyl)phosphine oxide have been reported previously. These resins have been used to fabricate graphite cloth laminates having excellent flame resistance. These composites did not burn even in pure oxygen. However, these resins were somewhat brittle. This paper reports the modification of these phosphorus-containing resins by an amine-terminated butadiene-acrylonitrile copolymer (ATBN) and a perfluoroalkylene diaromatic amine elastomer (3F). An approximately two-fold increase in short beam shear strength and flexural strength was observed at 7 percent ATBN concentration. The tensile, flexural, and shear strengths were reduced when 18 percent ATBN was used. Anaerobic char yields of the resins at 800 C and the limiting oxygen indexes of the laminates decreased with increasing ATBN concentration. The perfluorodiamine (3F) was used with both imide resins at 6.4 percent concentration. The shear strength was doubled in the case of the bisimide with no loss of flammability characteristics. The modified trisimide laminate also had improved properties over the unmodified one. The dynamic mechanical analysis of a four-ply laminate indicated a glass transition temperature above 300 C. Scanning electron micrographs of the ATBN modified imide resins were also recorded.
Document ID
Document Type
Conference Proceedings
Varma, I. K.
(NASA Ames Research Center Moffett Field, CA; Indian Institute of Technology, New Delhi, India)
Fohlen, G. M.
(NASA Ames Research Center Moffett Field, CA, United States)
Parker, J. A.
(NASA Ames Research Center Moffett Field, CA, United States)
Varma, D. S.
(Indian Institute of Technology, New Delhi, India; California, University Davis, CA, United States)
Date Acquired
August 12, 2013
Publication Date
January 1, 1984
Subject Category
Distribution Limits