Modification of cyanate ester resin by poly(ethylene phthalate) and related copolyesters

• Published in: Journal of applied polymer science Vol. 76; no. 2; pp. 208 - 219
• Main Authors: Iijima, Takao, Katsurayama, Satoru, Fukuda, Wakichi, Tomoi, Masao
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 11.04.2000; Wiley
• Subjects: 4-phenylene phthalate; Applied sciences; cyanate ester resin; Exact sciences and technology; fracture toughness; Mechanical properties; modification; Organic polymers; Physicochemistry of polymers; poly(ethylene phthalate); poly(ethylene phthalate-co-1; poly(ethylene phthalate‐co‐1,4‐phenylene phthalate); Properties and characterization; Strengthening; Property composition relationship; Cyclopolymerization; Mechanical properties; Triazine derivative polymer; Experimental study; Mechanism; Thermal stability; Thermosetting resin; Bending strength; Cyclopolymer; Curing(plastics); Morphology; Reaction mechanism; Water absorption; Phthalate copolymer; Tenacity; Phthalate polymer; Modified material
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/(SICI)1097-4628(20000411)76:2<208::AID-APP10>3.0.CO;2-N

Aromatic polyesters were prepared and used to improve the brittleness of the cyanate ester resin. The aromatic polyesters include poly(ethylene phthalate) (PEP) and poly(ethylene phthalate‐co‐1,4‐phenylene phthalate). The polyesters were effective modifiers for improving the brittleness of the cyanate ester resin. For example, inclusion of 20 wt % PEP (MW 19,800) led to a 120% increase in the fracture toughness (KIC) with retention in flexural properties and a slight loss of the glass transition temperature compared to the mechanical and thermal properties of the unmodified cured cyanate ester resin. The microstructures of the modified resins were examined by scanning electron microscopy and dynamic viscoelastic analysis. The thermal stability of the modified resins was lower than that of the unmodified resin as determined by thermogravimetric analysis. The water absorptivity of the modified resin increased significantly, compared to that of the unmodified cured cyanate ester resin. The toughening mechanism was discussed in terms of the morphological and dynamic viscoelastic behaviors of the modified cyanate ester resin system. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 208–219, 2000