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Two-dimensional nanofiber mats based on a mixture of polybenzimidazole with telechelic oligoperoxide are obtained by the method of electrospinning. It is shown that the reactive peroxide groups on the surface of nanofibers can be modified by the initiation of radical polymerization and grafting of various polymeric chains. The phenomenon of “negative” capacitance is detected for the impedance dependences of synthesized nanofibers. The influence of grafting of various polymeric chains to the surface of nanofibers on the polarization characteristics of nanocomposites is investigated. It is shown that some of the obtained structures are characterized by a combination of a low (< 1) tangent of dielectric losses in the infralow-frequency region (0.001–0.1 Hz) and high values of the dielectric permittivity (∼106). The possibilities of application of materials of this kind in the production of quantum batteries are discussed.

The objectives of this study were to examine the effects of fiber content and extrusion parameters on polybenzimidazole (PBI) fiber-reinforced polyethylene composites and to determine the optimum values for the tensile strength. The PBI fiber was physically mixed with high density polyethylene (HDPE) and then extruded through a twin screw extruder. The extrusion parameters were studied at different levels, barrel temperatures at 240°C, 250°C and 260°C and screw speeds at 12 rpm, 15 rpm and 18 rpm. The tensile strength was measured using a universal testing machine. A response surface experimental design using Design-Expert was applied to investigate the effect of fiber loading and extrusion parameters (barrel temperature, screw speed) on tensile properties of the resulting composite and consequently analyzing the optimized value for these parameters to yield maximum tensile strength. The analysis predicted a linear model which suggests that in order to achieve maximum tensile strength the screw speed should be 18 rpm, the barrel temperature at 240°C and at a fiber loading of 2%.

High density polyethylene (HDPE) and polybenzimidazole fiber (PBI) composites were prepared by melt blending in a twin screw extruder. The thermomechanical properties of PBI fiber reinforced HDPE composite samples (1%, 4%, and 8%) of fiber lengths 3 mm and 6 mm were investigated using differential scanning calorimeter (DSC), universal testing machine, rheometer, and scanning electron microscopy (SEM). The effects of fiber content and fiber lengths on the thermomechanical properties of the HDPE-PBI composites were studied. The DSC analysis showed a decrease in crystallinity of HDPE-PBI composites with an increase of fiber loading. SEM images revealed homogeneous distribution of the fibers in the polymer matrix. The thermal behavior of the composites was evaluated from thermogravimetric analysis and the thermal stability was found to increase with the addition of fibers. The evidence of homogeneous distribution was verified by the considerably high values of tensile strength and flexural strength. In the rheology study, the complex viscosities of HDPE-PBI composites were higher than the HDPE matrix and increased with the increasing of PBI fiber loading. POLYM. COMPOS., 2014. © 2014 Society of Plastics Engineers

Exposure to simulated ultraviolet sunlight at 50 °C and 50% relative humidity caused a significant deterioration in the mechanical performance of polyaramid and polyaramid/polybenzimidazole based outer shell fabrics used in firefighter jacket and pants. After 13 days of exposure to these conditions the tear resistance and tensile strength of both fabrics decreased by more than 40%. The polybenzimidazole containing fabric was less impacted by these conditions as it maintained approximately 20% more of its mechanical properties. These conditions also significantly degraded a water repellant coating on the fabric, which is critical to the water absorption performance of the outer shell fabrics. However, these conditions had little impact on the ultraviolet light protection of the outer shell as both fabrics still blocked 94% of ultraviolet light after 13 days of exposure. Confocal microscopy showed these conditions caused significant surface decomposition of and the switch from ductile to brittle failure of the polyaramid fibers. Cleavage of the amide linkages and the formation of oxidation species (as observed by Infrared spectroscopy) suggested these conditions caused photo-oxidation of the polyaramid fibers. There was little evidence of polybenzimidazole fiber degradation.

Polybenzimidazole (PBI) fibers are produced from polybenzimidazole polymer which has a high thermal and chemical strength with a long chain aromatic structure. These fibers are first used in protective technical textile products due to their good moisture regain and textile performance properties like good hand and drape. Today, in addition to protective textile market, they are also used in environmental friendly applications such as filtration, fuel cell and carbon capture systems. In this review, production, properties and application areas of polybenzimidazole (PBI) fibers are discussed.

About 8 years ago, Brinker and Robinson [l] invented the first aliphatic polybenzimidazoles. Two years later, aromatic polybenzimidazoles with impressive thermal properties were synthesized by Vogel and Marvel [2, 3] at the University of Illinois and later at Du Pont. Since then, high performance polybenzimidazoles received a great deal of attention by academia, U. S. government, and industry. Various new polybenzimidazoles have been invented, as reviewed in Refs. 4–12. Hoechst Celanese commercialized polybenzimidazole fiber for thermal protective clothing and fireblocking applications in 1983. In the mid 1980s, both Hoechst Celanese and Alpha Performance Company developed the technology to mold polyben- zimidazole parts (under the trade name of Celazole®). Alpha took over Celazole® technology completely in 1995 and continued marketing polybenzimidazole molded parts as sealing elements in high-temperature corrosive environments. Poly (2,2′-(m-phenylene)-5,5′ bibenzimidazole) is their product comp...

Derivatized polybenzimidazole (PBI) fiber is a unique material that offers a com bination of high performance and improved comfort properties. PBI has excellent thermal and chemical resistance and significantly reduced flame shrinkage; it also possesses good moisture and tactile properties which lead to improved wearer comfort when used in thermal protection clothing. A series of subjective wearer evaluations has shown that PBI exhibits comfort ratings equivalent to 100% cotton.

Celanese PBI is a derivatized polybenzimidazole fiber possessing a unique balance of properties that permit it to meet critical cost/performance criteria in demanding environments. The fiber, a modification of previously documented earlier versions, has excellent textile, tactile, thermal, and chemical resistance properties and sig nificantly reduced flame shrinkage, all of which are fully described. These properties permit the fiber to be used as an alternative to asbestos, in high temperature filtration fabrics, in thermal protection clothing, and in numerous other high tem perature and chemical resistance applications. Several specific applications are described along with performance results. A new production facility will provide commercial quantities beginning in early 1983.