Novel modification of cyanate ester by epoxidized polysiloxane

Abstract

A novel modification of cyanate ester (CE) resin by epoxidized polysiloxane (E-Si) has been developed, and the modified system is coded as CE/E-Si. E-Si was prepared by the reactions among octamethylcyclotetrasiloxane, hexamethyldisiloxane, (3-aminopropyl)-methyldiethoxysilane, and diglycidyl ether of bisphenol-A resin. Six formulations were designed to evaluate the effect of the weight ratio between CE and E-Si on performance parameters. Results reveal that the addition of E-Si in CE resin cannot only significantly decrease the curing temperature of the CE resin but also improve the water resistance and toughness of original CE resin. Moreover, these positive effects increase with the increase of E-Si concentration in CE/E-Si systems. Thermal property investigation shows that the glass-transition temperature and initial degradation temperature of CE/E-Si systems are lower than that of original CE resin. For the flexural properties of the CE/E-Si systems, the E-Si concentration in the system exists a threshold, that is, when the E-Si concentration is smaller than the threshold, original CE and CE/E-Si systems have similar flexural properties, whereas when the E-Si concentration is higher than the threshold, CE/E-Si systems have lower flexural properties than original CE resin. All these changes of properties are closely correlated to the structure alteration from neat CE to CE/E-Si networks.

Novel aluminum phosphate/cyanate ester composites: Thermodegradation behaviors and kinetic analyses

“…For inorganic fillers-filled polymeric composites, the conclusion of the fillers effect on the thermodegradation of the composites is not consistent with each other. For example, Gu and coworkers developed a novel CE resin modified by epoxidized polysiloxane (E-Si), coded as CE/E-Si; their investigations on thermal property showed that the glass transition temperature and initial degradation temperature of CE/E-Si system were lower than that of the original CE resin 15 ; similarly, study by Koo et al concluded that the incorporation of nano-SiC whiskers did not enhance the thermal stability of CE resin. 18 However, some researchers came out with contrary researches.…”

“…11,12 To date, some inorganic/CE hybrids have been studied, such as aluminum borate whisker/CE, polyhedral oligomeric silsesquioxanes/CE, and epoxidized polysiloxane/CE. [13][14][15] Results have proved that hybrids have better properties than original CE resin, and the properties of inorganic/CE hybrids are greatly depending on the property of inorganic materials. The properties of present inorganic/CE hybrids need to be further improved.…”

Modification of Thermoplastics with Reactive Silanes and Siloxanes

“…octamethylcyclotetrasiloxane (Me 2 SiO) 4 (D 4 ) with carbofunctional disiloxanes, which are carried out in acidic or basic media (Scheme 2) (Yilgor & McGrath, 1988;Harabagiu et al, 1996). For example, by the equilibration of D 4 (D = Me 2 SiO) with (3-aminopropyl)methyldiethoxysilane and hexamethyldisiloxane Me 3 SiOSiMe 3 , polydimethyl-co-[(aminopropyl)(methyl)]-siloxane oils (containing side aminopropyl groups) were prepared (Yang et al, 2007).…”

“…The carbofunctional polysiloxanes, in which alkylfunctional groups are attached to the silicon atoms inside of the polymer chain were also prepared by the catalytic equilibration of cyclotetrasiloxane, containing aminopropyl functional groups (D 3 D NH2 ), with decamethyltetrasiloxane MD 2 M (D = Me 2 SiO, M = Me 3 SiO 0.5 ) in the presence of Me 4 NOSiMe 3 (TMAS) (Zhou et al, 2004;Yang et al, 2007) Scheme 3. The preparation of CFPS with pendant aminopropyl functional groups.…”

Novel toughened cyanate ester resin with good dielectric properties and thermal stability by copolymerizing with hyperbranched polysiloxane and epoxy resin

“…Among them, the modification of BCE resin by epoxy (EP) resin has proved to be an effective route, which not only effectively improves the toughness, but also reduces high curing temperature of BCE. However, compared with pristine BCE resin, EP/BCE resin has declined heat resistance and poorer dielectric properties 11. These flaws limit the widespread application of cured EP/BCE resins.…”