Influence on fracture toughness arising from controlled morphology of multiphase toughened epoxy resins in the presence of fibre reinforcement

The epoxy resins were toughened with reactive core-shell nanoparticles(CSNPs) with butyl acrylate (BA) as the core and methyl methacrylate (MMA) copolymerizing with glycidyl methacrylate (GMA) as the shell. The chemical structure of the CSNPs was characterized by FT-IR. The morphology of toughened epoxy networks were analyzed by SEM and TEM, and their adhesion properties were also detected. The results show that mixing methods and CSNP concentration have great influence on the morphology and adhesion properties of the toughened epoxy networks. CSNPs are uniformly dispersed in the epoxy resins by the grinding method. The modified epoxy networks obtained from the modified epoxy networks prepared by the grinding method(MEPN2) with 10 wt% CSNPs show the best adhesion properties, and the increase in maximum peel strength, 25°C sheer strength and 150°C sheer strength of the modified epoxy networks is 401.3% , 46.9% and 27.6% respectively over the unmodified epoxy networks due to the small-scale coagulations of CSNPs.

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Enhanced fracture toughness of epoxy resins with novel amine-terminated poly(arylene ether sulfone)-carboxylic-terminated butadiene-acrylonitrile-poly(arylene ether sulfone) triblock copolymers

Journal of Applied Polymer Science ◽

10.1002/app.10390 ◽

2002 ◽

Vol 84 (8) ◽

pp. 1556-1565 ◽

Cited By ~ 6

Author(s):

H. R. Kim ◽

B. Y. Myung ◽

T. H. Yoon ◽

K. H. Song

Keyword(s):

Fracture Toughness ◽

Epoxy Resins ◽

Triblock Copolymers ◽

Arylene Ether

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Adhesive Through-Reinforcement Improves the Fracture Toughness of a Laminated Birch Wood Composite

Advances in Materials Science and Engineering ◽

10.1155/2017/5637248 ◽

2017 ◽

Vol 2017 ◽

pp. 1-11

Author(s):

Wenchang He ◽

Philip D. Evans

Keyword(s):

Fracture Toughness ◽

Glass Fibre ◽

Adhesive Bond ◽

Fibre Reinforcement ◽

Wood Composite ◽

Birch Wood ◽

Wood Composites ◽

Polyurethane Adhesive ◽

Model Composite ◽

Fibre Bridging

In this paper we test the hypothesis that adhesive through-reinforcement in combination with glass-fibre reinforcement of adhesive bond lines will significantly improve the fracture toughness of a laminated birch wood composite. We test this hypothesis using a model composite consisting of perforated veneer that allowed a polyurethane adhesive to penetrate and reinforce veneers within the composite. Model composite specimens were tested for mode I fracture properties, and scanning electron microscopy was used to examine the microstructure of fracture surfaces. Our results clearly show that through-reinforcement, and also reinforcing adhesive bond lines with glass-fibre, significantly improved fracture toughness of the birch wood composite. Our results also indicate that improvements in fracture toughness depended on the level of reinforcement. Improvements in fracture toughness were related to the ability of the reinforcement to arrest crack development during fracture testing and the fibre bridging effect of glass-fibre in adhesive bond lines. We conclude that through-reinforcement is an effective way of improving the fracture toughness of laminated wood composites, but further research is needed to develop practical ways of creating such reinforcement in composites that more closely resemble commercial products.

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