Effect of the Structure Morphology on the Mechanical Properties of Crumpled Graphene Fiber

Crumpled graphene fiber is a promising structure to be a graphene precursor to enhance the production and mechanical properties of various carbon fibers. The primary goal of the present work is to study the crumpled graphene of different morphologies using molecular dynamics simulations to find the effect of the structural peculiarities on the mechanical properties, such as the tensile strength, elastic modulus, and deformation characteristics. Mono- and poly-disperse structures are considered under uniaxial tension along two different axes. As it is found, both structures are isotropic and stress–strain curves for tension along different directions are very similar. Young’s modulus of crumpled graphene is close, about 50 and 80 GPa; however, the strength of the polydisperse structure is bigger at the elastic regime. While a monodisperse structure can in-elastically deform until high tensile strength of 90 GPa, structure analysis showed that polydisperse crumpled graphene fiber pores appeared two times faster than the monodisperse ones.

Parameters of diff erent types of structures and physical-mechanical characteristics of composites based on domestic polysulfone

Using the glass-fi lled composites based on polysulfone domestic brand PSF-190 as an example, the problems of constructing of structure of dispersed-fi lled polymer composite materials (DFPCM) are considered for the fi rst time. The generalized parameters of disperse structures and their classifi cation according to the structural principle are taken into account. It was established for the fi rst time that the complex of physical-mechanical characteristics of DFPCM based on PSF-190 + glass fi ber is determined by the structure, type of lattice, packaging, and generalized parameters. The dependences of the physicomechanical characteristics of DFPCM on the generalized parameter of the dispersed structure (Θ) are given. It has been established that for medium-fi lled disperse systems (Θ = 0,60–0,45 v.f.) maximum physico-mechanical characteristics of the DFPCM are achieved at a content of short glass fi ber of 0,14–0,18 v.f. The compositions of domestic glass-fi lled polymeric composite materials based on domestic PSF-190 with specifi ed types of lattices, structures and generalized parameters, which are practically not inferior to foreign analogues by a set of operational properties, have been developed.

Optimization of the foam generation regime in a cylindrical channel

Mass and multi-purpose use of air-mechanical foams from gas-liquid mixtures predetermines the need to establish the physical and technical patterns of their formation in high-efficiency generating plants. The paper presents the results of optimizing the foaming regimes, taking into account the joint influence of all probable factors coming from the technology of the process of obtaining stable disperse structures. A regression model has been developed that makes it possible to determine optimal parameters of the foaming regime with the required structure and thermal properties.