The compressive properties of expandable microspheres/epoxy foams

Wang, Lijun; Yang, Xu; Zhang, Jing; Zhang, Chun; He, Li

doi:10.1016/j.compositesb.2013.09.030

Cited by 107 publications

(96 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…26,44 Here, the compression strength and modulus obtained under different conditions are respectively plotted against the densities of the corresponding foams in Fig. 13.…”

Section: Mechanical Propertiesmentioning

confidence: 99%

Rigid thermosetting epoxy/multi-walled carbon nanotube foams with enhanced conductivity originated from a flow-induced concentration effect

Liu

Bao

et al. 2016

RSC Adv.

View full text Add to dashboard Cite

Herein, multi-walled carbon nanotube (MWCNT) reinforced rigid epoxy foams were innovatively prepared using expandable microspheres. A two-step technique, including prepolymerization and consecutive foaming, was employed to avoid the thermal degradation of epoxy due to the uncontrolled violent curing reaction. The effects of foaming on the MWCNT inter-connectivity, electrical percolation threshold, and through-plane electrical conductivity were investigated. Moderately foamed epoxy/ MWCNT composites were confirmed to have better conductivity than their solid counterparts at the same MWCNT content. An effect we called flow-induced concentration increases the inter-connectivity by separating MWCNTs from a flowing matrix caused by thermally triggered expansion of microspheres, and changes the MWCNT distribution. For the foamed composites with 2 wt% microspheres, the electrical percolation threshold is approximately 0.3 wt% and the conductivity is obviously higher than that of the solid counterpart. Relationships between microstructures and conductivities were also discussed. The mechanical property and cellular structures of conductive foams obtained under different foaming temperatures, prepolymerization time, microsphere and MWCNT contents were respectively evaluated. All the results reveal that lightweight conductive epoxy foams with lower filler content and enhanced conductivity can be fabricated for applications in electronics, automobiles, and aerospace.

show abstract

“…26,44 Here, the compression strength and modulus obtained under different conditions are respectively plotted against the densities of the corresponding foams in Fig. 13.…”

Section: Mechanical Propertiesmentioning

confidence: 99%

Rigid thermosetting epoxy/multi-walled carbon nanotube foams with enhanced conductivity originated from a flow-induced concentration effect

Liu

Bao

et al. 2016

RSC Adv.

View full text Add to dashboard Cite

show abstract

“…At high temperature, the salt decomposes and the amine thus formed reacts with epoxy. Moreover, some systems can be physically blown by gas issued from boiling of monomers [54] or heating of volatile liquids incorporated into the formulation [55,56]. However, all these methods of blowing reaction are performed at rather high temperature.…”

Section: Introductionmentioning

confidence: 99%

Room temperature flexible isocyanate-free polyurethane foams

Cornille¹,

Guillet²,

Benyahya³

et al. 2016

European Polymer Journal

119

View full text Add to dashboard Cite

“…3 Multiwalled carbon nanotube (MWCNTs) is one of the most promising fillers with small diameter, large aspect ratio. Though thermosetting polymer foams exhibit exceptional low moisture absorption, sufficient mechanical strength, good corrosion-resistant properties, high heat-resistance, 19 and have promising prospect to substitute thermoplastic polymer foams, but there are a few relative researches about them until now. [12][13][14] Thermoplastic foams are mostly studied as matrixes to fabricate composites by loading of those carbonaceous fillers, such as polyethylene, 15 polystyrene, 16 polypropylene, 9 polylactide, 2 and poly(methyl methacrylate).…”

Section: Introductionmentioning

confidence: 99%

“…[19][20][21] These microspheres were prepared by low-boiling blowing agent encapsulated in a copolymer shell. Previously, an untraditional foaming method using expandable microspheres (Expancel) was adopted by our group to efficiently decrease the density of target composites.…”

Section: Introductionmentioning

confidence: 99%

Epoxy composite foams with excellent electromagnetic interference shielding and heat‐resistance performance

Pan

Bao

2017

J of Applied Polymer Sci

View full text Add to dashboard Cite

Epoxy composite foams with improved heat-resistant property and efficient electromagnetic interference shielding effectiveness (EMI SE) were fabricated through a two-step foaming technique. A sort of novel and untraditional expandable microspheres was adopted to reduce the density of prepared materials. A multiscale conductive network system composed of multiwalled carbon nanotubes (MWCNTs) and nickel-plated carbon fibers (NiCFs) was introduced in these foams. Benefitting from the synergistic effect between NiCFs and MWCNTs, the multiscale epoxy foam with best comprehensive performance achieved a greatly enhanced T g at 178.3 8C and an exceptional specific EMI SE ranging from 52.8 to 72.6 dB cm 3 g 21 in X band (8.2-12.4 GHz) at low filler loading. These properties are greatly better than original epoxy foam with a T g of 157.8 8C and specific EMI SE of 1.0-6.4 dB cm 3 g 21 . Their shielding mechanisms were discussed and the results showed that reflection is dominating. The effects of microspheres content, foaming temperature, NiCFs content, and length were investigated. In general, we provided a feasible, convenient and cost-effective method to fabricate light-weight, heat-resistant thermosetting epoxy foams with sufficient EMI shielding performance which has a potential to be applied in aerospace or electronic devices.

show abstract

The compressive properties of expandable microspheres/epoxy foams

Cited by 107 publications

References 30 publications

Rigid thermosetting epoxy/multi-walled carbon nanotube foams with enhanced conductivity originated from a flow-induced concentration effect

Rigid thermosetting epoxy/multi-walled carbon nanotube foams with enhanced conductivity originated from a flow-induced concentration effect

Room temperature flexible isocyanate-free polyurethane foams

Epoxy composite foams with excellent electromagnetic interference shielding and heat‐resistance performance

Contact Info

Product

Resources

About