Toughening of Epoxy Resins with Thermoplastics: 3. An Investigation into the Effects of Composition on the Properties of Epoxy Resin Blends

✍ Scribed by Hourston, D. J.; Lane, J. M.; Zhang, H. X.

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 454 KB
• Volume: 42
• Category: Article
• ISSN: 0959-8103
• DOI: 10.1002/(sici)1097-0126(199704)42:4<349::aid-pi710>3.0.co;2-3

✦ Synopsis

Three di †erent epoxy resins, based on the diglycidylether of bisphenol A (DGEBA), triglycidyl-p-aminophenol (TGPAP) and tetraglycidyldiaminodiphenylmethane (TGDDM), which are di-, tri-and tetrafunctional, respectively, were mixed in varying proportions and cured with both 3,3@-diaminodiphenylsulphone and 4,4@-[1,4-phenylene(1-methylethylidene)]bis(2, 6-dimethylbenzenamine) (EPON 1062-M from Shell). All the blends could be satisfactorily cured and gave homogeneous materials. The dynamic mechanical and fracture properties of the cured materials were measured. It was found that the glass transition temperature varied with composition systematically, whereas values of the strain energy release rate and the stress intensity factor (G 1c ) ( K 1c ) showed relatively small variations with the blend composition.

Toughened epoxy resins were prepared by adding a polyetherimide (PEI), in varying proportions, to the resin mixture. The "toughenabilitiesÏ of di †erent resins, or resin mixtures, were compared. This showed that the 75/25 TGPAP/ DGEBA resin mixture was the most toughenable. Adding 20% of PEI led to a more than three-fold increase of the value.