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Epoxy/core-shell particle blends were prepared using a diglycidylether of bisphenol A epoxy and acrylics-type core-shell particles. The impact strength of the blends was tested, and the result showed that the epoxy was greatly toughened with optimum core-shell particle content. Meanwhile, the dielectric properties of both epoxy and its blends were investigated using a broadband dielectric analyzer. It was found that the dielectric constant of the epoxy blends with lower core-shell particle content were less than that of the epoxy in the investigated frequency range, while the dielectric loss was less than that of the neat epoxy over a low frequency range, even for the epoxy blends with the optimum core-shell particle content. The dielectric breakdown strength of the epoxy blends at room and cryogenic temperature were also investigated. To identify the primary relationship of the above properties and structure of the epoxy blends, the microstructure of the core-shell particle and the morphology of the samples were observed by transmission electron microscopy and scanning electron microscopy. It was considered that these epoxy/core-shell particle blends with improved toughness and desirable dielectric properties could have a potential application in the insulation of electronic packaging system.

Section: Introductionmentioning

confidence: 99%

Simultaneously improved toughness and dielectric properties of epoxy/core‐shell particle blends

Wan

Jian

et al. 2007

“…Several methods have been proposed for increasing the toughness of epoxy resins and one of the most effective approaches is the introduction of a second component which is capable of phase separation as reactive liquid rubber, thermoplastic, or core‐shell particles . Considerable attention has been paid to the use of functionalized curing agents for epoxy resins.…”

Section: Introductionmentioning

confidence: 99%

Toughening epoxy resin with blocked isocyanate containing soft chain

Lou

Xiao

Wang

et al. 2014

A series of imidazole (MI) blocked 2,4‐toluene diisocyanate (TDI) with polyethylene glycol (PEG‐400) as soft segment (PEG‐MI‐b‐TDI) were synthesized for toughening and curing the bisphenol A type epoxy resin (E‐44). Fourier transform infrared (FTIR) spectrum indicates that the NCO groups of the isocyanate molecule are blocked with MI. For curing epoxy systems, elimination of epoxy group and the formation of urethane bonds were studied by FTIR spectroscopy. The results of mechanical property were shown that the tensile shear and impact strengths of neat MI and MI‐b‐TDI cured E‐44 are lower than those of PEG‐MI‐b‐TDI cured E‐44. Based on the scanning electron microscope studies, microstructure evolutions of the E‐44 cured by different curing agents were imaged. The mechanical, thermal, and dynamic mechanical properties were measured by universal testing machine, differential scanning calorimeter and dynamic mechanical analyzer (DMA). The toughness of E‐44 cured by PEG‐MI‐b‐TDI was effectively improved without sacrificing the tensile shear strength. Based on the DMA studies, the long soft chain of PEG brought in a noticeable lowering in the glass transition temperature (Tg). The glass transition temperature is near 165°C for the neat MI cured E‐44, which is higher than the Tgs of the other curing agents cured epoxy. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41345.

“…The methods of toughened epoxy generally lead to the loss of modulus, glass transition temperature, and solvent resistance, thus limiting the number of high‐performance application of these resins. The most effective approach is the introduction of a second component which is capable of phase separation as reactive liquid rubber,12–14 thermoplastic,15–17 or core‐shell particles 18–23. Considerable attention has been paid to the use of functionalized curing agents for epoxy resins.…”

Section: Introductionmentioning

confidence: 99%

“…The most effective approach is the introduction of a second component which is capable of phase separation as reactive liquid rubber, [12][13][14] thermoplastic, [15][16][17] or core-shell particles. [18][19][20][21][22][23] Considerable attention has been paid to the use of functionalized curing agents for epoxy resins. By designing molecules' structure of curing agents or synthesizing flexible curing agents, the toughness, crack resistance, and other properties of the epoxy resins could be improved, 24,25 what is popular increasingly from now on.…”

Section: Introductionmentioning

confidence: 99%

Toughening of epoxy resins by modified m‐phenylene diamine having soft ether chain

Lou

Kong

Wang

et al. 2011

A new soften curing agent for toughening epoxy resins was synthesized by m‐phenylene diamine modified with epoxypropyl butyl ether. The curing processes of epoxy resin/modified m‐phenylene diamine were traced by differential scanning calorimetry (DSC), then kinetic parameters, ΔE and n, were deduced. Fourier transform infrared (FTIR) analysis showed that the longer the reaction time was, the smaller the absorption peaks of epoxy group were. The results of the mechanical properties demonstrated that the impact property of the epoxy resin cured by modified m‐phenylene diamine at the moderate temperature was better than that of cured by unmodified one because of the introduction of soft ether chain. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012