Application Progress of PALS in the Correlation of Structure and Properties for Graphene/Polymer Nanocomposites

Abstract

Giving a deep insight into the microstructure, and realizing the correlation between microstructure and properties is very important to the precise construction of high-performance graphene/polymer nanocomposites (GPN). For the promising application in microstructure characterization, much attention has been focused on the effective technique of positron annihilation lifetime spectroscopy (PALS). Based on the introduction of the basic principle, this review summarized the application progress of PALS in the correlation of microstructure and properties for GPN, especially for the characterization of free volume and interfacial interaction, and the correlation of these microstructures and properties.

Varying the Stiffness and Diffusivity of Rod‐Shaped Microgels Independently through Their Molecular Building Blocks

“…Here, different hierarchical structures of the internal structure of hydrogels and microgels play a role when characterizing the stiffness and diffusion properties. Thereby, it is important to differentiate between i) macropores (≥50 μm) [31] that are formed during demixing upon polymerization, [32–34] ii) mesopores (2–50 nm) [31] that are formed due to crosslink density fluctuations and network inhomogeneities, [35,36] and iii) micropores (≤2 nm) [31] that reflect the free volume inside the polymer coils themselves, [37] and are highly dependent on the polymer and solvent [38–40] …”

“…Thereby, it is important to differentiate between i) macroopores (� 50 μm) [31] that are formed during demixing upon polymerization, [32][33][34] ii) mesopores (2-50 nm) [31] that are formed due to crosslink density fluctuations and network inhomogeneities, [35,36] and iii) micropores (� 2 nm) [31] that reflect the free volume inside the polymer coils themselves, [37] and are highly dependent on the polymer and solvent. [38][39][40] To investigate the internal structure, we produce bulk hydrogels as described above using a UV-LED (λ = 365 nm) with a dose of 467 mJ mm À 2 and analyse the diffusion of differently sized fluorescein isothiocyanate (FITC)-dextrans through the bulk of the gels over a distance of 100 μm using confocal laser scanning microscopy (CLSM) (in height, zdirection in the coordinate system of the CLSM) (see Figure 1d-f). This allows us to probe the hydrogels for diffusion.…”

Synergistic Effect of Aluminum Nitride and Carbon Nanotube-Reinforced Silicon Rubber Nanocomposites

“…To address the deficiency of single filler-incorporated polymer composites, a synergistic effect based on hybrid fillers was developed for the construction of high-performance composites [ 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. The hybrid filler system can accelerate the construction of a continuous filler structure and upgrade the dispersion/exfoliation of each filler.…”

Effect of Carbon Nanoparticles Morphology on the Properties of Poly(styrene-b-isoprene-b-styrene) Elastomer Composites

“…Due to its excellent electrical, mechanical, optical, and thermal properties, carbon nanoparticles such as fullerene, carbon nanotubes, graphene, and carbon black (Figure 1) have been extensively applied in fabricating high-performance polymer nanocomposites [8][9][10][11][12]. To further improve the comprehensive properties of SIS, many nanocomposite-based SIS and carbon nanoparticles were reported [13,14].…”