Synergistic enhancement effect of flame-grown carbon nanotubes and chopped carbon fibers on adhesive joint of thermosetting laminate

The theoretical model, using the notions of fractal analysis is proposed for description of strength of nanocomposites polymer/2D-nanofiller on the example of nanocomposites polyvinylalcohol/boron nitride. For correct description of strength of these two-phase nanomaterial the knowledge of initial characteristics of matrix polymer (stress of fracture), geometrical parameters of nanofiller and level of interfacial adhesion polymer matrix-nanofiller is necessary. The indicated level, characterizing by shear interfacial strength, was determined theoretically within the framework of fractal conception of adhesion. Its absolute values found high enough – they are comparable with this characteristic in systems polymer-carbon nanotubes and are higher essentially than in systems polymer-microfiber (glassy and carbon fibers). This factor defines high enough strength of the considered nanocomposites. The important factor for fracture process of nanomaterials is aggregation of initial platelets of nanofiller, which forms “packets” (tactoids) of such platelets. The relatively small aggregation degree of nanofiller gives appreciable reduction of strength of nanocomposites polymer/2D-nanofiller. The indicated reduction is connected with transition of 2D-nanofiller structure from exfoliated to intercalated one, i.e. from separate platelets to their tactoids.

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Synergistic Enhancement Effect of Palladium-Silver Alloy Nanoparticle Catalysts Towards High-Sensitive Hydrogen Detection

2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII) ◽

10.1109/transducers.2019.8808575 ◽

2019 ◽

Author(s):

Dongsheng Xu ◽

Dan Zheng ◽

Pengcheng Xu ◽

Ying Chen ◽

Xinxin Li

Keyword(s):

Enhancement Effect ◽

Silver Alloy ◽

Hydrogen Detection ◽

Nanoparticle Catalysts ◽

Synergistic Enhancement ◽

Palladium Silver

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Modified rule of mixtures and Halpin–Tsai model for prediction of tensile strength of micron-sized reinforced composites and Young’s modulus of multiscale reinforced composites for direct extrusion fabrication

Advances in Mechanical Engineering ◽

10.1177/1687814018785286 ◽

2018 ◽

Vol 10 (7) ◽

pp. 168781401878528 ◽

Cited By ~ 8

Author(s):

Zirong Luo ◽

Xin Li ◽

Jianzhong Shang ◽

Hong Zhu ◽

Delei Fang

Keyword(s):

Carbon Nanotubes ◽

Tensile Strength ◽

Young’S Modulus ◽

Carbon Fibers ◽

Epoxy Resins ◽

Young's Modulus ◽

Resin Matrix ◽

Reinforced Composites ◽

Rule Of Mixtures ◽

Combined Use

A modified rule of mixtures is required to account for the experimentally observed nonlinear variation of tensile strength. A modified Halpin–Tsai model was presented to predict the Young’s modulus of multiscale reinforced composites with both micron-sized and nano-sized reinforcements. In the composites, both micron-sized fillers—carbon fibers—and nano-sized fillers—rubber nanoparticles and carbon nanotubes—are added into the epoxy resin matrix. Carbon fibers can help epoxy resins increase both the tensile strength and Young’s modulus, while rubber nanoparticles and carbon nanotubes can improve the toughness without sacrificing other properties. Mechanical experiments and scanning electron microscopy observations were used to study the effects of the micron-sized and nano-sized reinforcements and their combination on tensile and toughness properties of the composites. The results showed that the combined use of multiscale reinforcements had synergetic effects on both the strength and the toughness of the composites.

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