Correlation between microstructure and properties of graphene oxide/waterborne polyurethane composites investigated by positron annihilation spectroscopy

Abstract

Qualitative and quantitative descriptions of interfacial interactions for graphene oxide/waterborne polyurethane composites.

Effect of π–π Stacking Interfacial Interaction on the Properties of Graphene/Poly(styrene-b-isoprene-b-styrene) Composites

“…These results demonstrate that a π–π stacking interaction can be formed in the slow self-assembly process; thus, the solution mixing followed by evaporation-induced self-assembly process is an effective method to obtain strong interfacial interaction [ 24 , 25 ]. These strong interfaces can facilitate stress dispersion and transport performance [ 10 , 11 , 12 , 13 , 14 ], which has an important effect on the properties of the graphene/SIS composites.…”

“…It is found that all the composites present similar degradation behavior to pristine SIS, and the composites have an obvious improved thermal stability in comparison to pure SIS, especially in the range of 30–350 °C. This improvement in thermal stability could be attributed to the tortuous path effect, which formed between graphene and SIS through π–π stacking [ 10 , 40 ]. The decreased degradation rate with increase in graphene content can be ascribed to the effective obstruction of low molecules from degraded SIS, and the shield function of the heat [ 32 ].…”

“…Many methods were developed for the fabrication of graphene-based polymer composites, such as solution mixing, melt blending, and in situ polymerization. Among these methods, solution mixing has been demonstrated to be an effective way to obtain satisfactory dispersion [ 10 , 11 , 12 ].…”

“…The other important factor that influence the properties of graphene-based polymer composites is the interfacial interaction, which determines the stress dispersion and transport performance of the obtained nanocomposites [ 10 , 11 , 12 , 13 , 14 ]. As reported by the group of Wang [ 15 ], the interfacial orientation of the polystyrene phenyl groups in contact with graphene was revealed by sum frequency generation vibration spectroscopy.…”

Insight into the role of free volume in irradiation resistance to discoloration of lead‐containing plexiglass

“…The τ 3 of the positronium corresponds to the pick-off annihilation of ortho-positronium (o-Ps) in the free-volume holes, which is the longest lifetime component. Employing the Tao-Eldrup model, [44][45][46] the average radius of the free volume pore can be estimated, as expressed as:…”