Results from characterization of spinning solutions obtained using meta-aramid wastes from fabrication of special clothing and fully used special clothing are reported. Recycling technology for fibers including stages of fabric grinding, spinning solution preparation, wet spinning of fibers, and orientation drawing was proposed. Thermal drawing following spinning was found to increase in the strength of the resulting fibers by 1.8-2.5 times. The heat resistance of regenerated fibers decreased by almost 7
Curing of epoxide binder in the presence of oxidized PAN-TT modified by AGM-9 was shown to occur under milder conditions than for unfilled matrices. This was probably due to chemical interaction between organic functional groups of 3-aminopropyltriethoxysilane deposited beforehand onto the surface of the starting polyacrylonitrile cord and active epoxide oligomers that resulted in high adhesive interaction at the interface between the fiber and matrix in the composite. This was confirmed by scanning electron microscopy and led to increased resistance of composite samples to mechanical loads and their improved heat resistance.
Results from development of a Polikon C cation-exchange membrane by polycondensation filling in situ based on novolac phenol-formaldehyde fibrous material are reported. The use of a fibrous matrix as a nanoreactor was shown to allow the synthesis of an ion-exchange phase directly in the fiber structure, which guaranteed high integration of the components and obviated the need to use an inert binder. The obtained membranes were characterized by a static exchange capacity of 3 mg-eq/g and a monolithic structure and lacked sharp interphase boundaries. The method opened prospects for designing new types of functional fibrous materials for separation and purification membrane technologies.
The properties of models of lateral support of reinforced concrete rail fastenings made of fiber-reinforced polyamide composites have been studied by prototyping method using T-FLEX CAD software, which enabled analysis of the stressed-strained state and the stability of the studied parts in virtual operating conditions. It has been shown that the developed materials based on polymerized-reinforced polyamide-6 containing 10
A model has been developed to predict the degree of impregnation of a fabric made of polypropylene fibers with a linear density of 0.66 tex and a bulk density of 85 kg/m3 based on two technological variables, such as the polyurethane concentration in an aqueous dispersion and the gap between the squeezing rollers. The degree of impregnation of the fabric with a relatively low density depends on the gap between the squeezing rollers and negligibly on the concentration of polyurethane in the aqueous dispersion. The degree of fabric impregnation is regulated with a gap of less than 0.25 mm between the squeezing rollers. If the gap is wider, the impregnation degree reaches the limit at different polyurethane concentrations.
