Accession Number : ADA223277


Title :   Influence of Expanding Monomer on Carbon Fiber Reinforced Epoxy Composites


Descriptive Note : Research and development rept. 10 Jan 1988-11 Jan 1989,


Corporate Author : DAVID TAYLOR RESEARCH CENTER BETHESDA MD SHIP MATERIALS ENGINEERING DEPT


Personal Author(s) : Howell, Barbara F.


Full Text : http://www.dtic.mil/get-tr-doc/pdf?AD=ADA223277


Report Date : JUN 1990


Pagination or Media Count : 25


Abstract : In this investigation it was confirmed that copolymerization of dinorbornene spiroothocarbonate (DNSOC) with expoxy can eliminate sample shrinkage and even produce sample expansion. To maximize control of shrinkage, it is important to bring epoxy to the gel stage before the DNSOC begins to copolymerize. Embedded single filament tensile test results were compared for samples containing DGEBA-epoxy cured with m-phenylene diamine (mPDA) with those for DNSOC-epoxy cured with m-phenylene diamene (mPDA) with those for DNSOC-epoxy samples cured with mPDA and BF3.diethylenetriamine for which BF3 was used to catalyze polymerization of the DNSOC. As compared with epoxy, the DNSOC sample showed ten-fold reductions in interfacial tensile stress, 10 C reduction in Tg, and 40% reduction in tensile strength. The tensile modulus was not reduced and the sample showed no shrinkage. No stress patterns were seen in the DNSOC-epoxy with a polarizing microscope. It is concluded that smaller amounts of DNSOC than 12% can be used to produce optimal effects on mechanical properties. (jes)


Descriptors :   *EPOXY COMPOSITES , *FIBER REINFORCED COMPOSITES , *CARBON FIBERS , POLARIZATION , TENSILE STRENGTH , OPTIMIZATION , INTERFACES , POLYMERIZATION , TENSILE STRESS , PATTERNS , MICROSCOPES , GELS , SHRINKAGE , MECHANICAL PROPERTIES , COPOLYMERIZATION , STRESSES , CONTROL


Subject Categories : LAMINATES AND COMPOSITE MATERIALS


Distribution Statement : APPROVED FOR PUBLIC RELEASE