In this study, natural fiber‐reinforced polymer nanocomposites were prepared from high‐density polyethylene (HDPE), abaca fiber, and nanoprecipitated calcium carbonate (NPCC) using the hot press technique. The study investigated the influence of untreated and alkali‐treated woven abaca fabric and NPCC hybrid reinforcement on the thermomechanical behavior of the natural fiber composites. The HDPE with different amounts of NPCC was melt‐blended in a twin‐screw extruder followed by hot press to produce sheets. A lamination of composites containing alternating layers of HDPE sheets with different amounts of NPCC and layers of untreated and alkali‐treated woven abaca fabric was produced using a hot press machine. The resulting material was composed of 20% weight ratio of woven abaca fibers. The tensile strength showed that the nanocomposite exhibited a high tensile value of 60.1 MPa with alkali‐treated abaca and 1% NPCC. However, a further increase in the NPCC concentration beyond 1% reduced the mechanical strength of the nanocomposite. The thermal stability of the abaca fiber‐reinforced nanocomposite improved with addition of NPCC. Scanning electron microscopic analysis demonstrated that alkali‐treated abaca and 1% NPCC improved the adhesion and compatibility between the fiber and polymer matrix. The potential applications of this natural fiber‐reinforced composite are for automotive and construction materials.

Kevlar [poly (p-phenilylene terephtalamide)], was used as a precursor in the preparation of activated carbon fibers. For this intention, physical and chemical activations were carried out. Activated fibers were physically prepared from the carbonization of the Kevlar and its later activation with CO 2 and steam of water, by the other hand; the chemically activated fibers were obtained by means of the impregnation of the material with phosphoric acid and their later carbonization. Different conditions were used and preliminary analyses of the precursor were taken into account (TGA-DTA / IR). The resulting fibers were characterized by N 2 (77K) adsorption, infrared spectroscopy, SEM, and immersion calorimetry. Yields and Burn off were also evaluated. The results shows that if you want to synthesize activated carbon fibers from Kevlar strong conditions respect to the commonly used such as water steam, high phosphoric acid concentrations and methods of impregnation are the ones who allows the development of optimal surface areas and pore volumes.

Kevlar [poly (p-phenilylene terephtalamide)], was used as a precursor in the preparation of acti-vated carbon fibers. For this intention, physical and chemical activations were carried out. Activated fiberswere physically prepared from the carbonization of the Kevlar and its later activation with CO 2 and steam ofwater, by the other hand; the chemically activated fibers were obtained by means of the impregnation of thematerial with phosphoric acid and their later carbonization. Different conditions were used and preliminaryanalyses of the precursor were taken into account (TGA-DTA / IR). The resulting fibers were characterizedby N 2 (77K) adsorption, infrared spectroscopy, SEM, and immersion calorimetry. Yields and Burn off werealso evaluated. The results shows that if you want to synthesize activated carbon fibers from Kevlar strongconditions respect to the commonly used such as water steam, high phosphoric acid concentrations and meth-ods of impregnation are the ones who allows the development of optimal surface areas and pore volumes.