Treated aramid fibers as reinforcement in nonpolar matrices

Abstract

SynopsisCrosslinked polyethylene finds extensive use in applications where improved thermal resistance is required. Furthermore, reinforced and crosslinked polyethylene presents high strength at elevated temperatures, so that the field of applications of such materials is considerably enlarged. Aramid fibers seem to be a promising reinforcement for the above materials since they combine high modulus with thermal resistance and light weight. The development of an adequate adhesive bond between aramid fiber and polyethylene matrix is of course the main problem, taking into consideration that both polyethylene and aramid present reduced chemical affinity to other substances. Thus, fiber pretreatment was performed in order to insert unsaturated groups in the aramid chain. These groups could be, in turn, grafted in the polyethylene backbone during the crosslinking reaction. The aramid fibers were treated with methacryloyl chloride, and then dispersed under stirring in 2% aqueous sodium hydroxide containing 0.5% of a nonionic surfactant. After washing and drying, the fibers were dry blended with polyethylene powder containing 2 phr dicumyl peroxide. The mixture was melt-blended in a Brabender plasticorder and tensile specimens were prepared. Tensile measurements and microscopy on the fracture surface were carried out in order to evaluate changes introduced in the fiber by surface treatment.

Strain rate effect on composites with epoxy matrix filled by cork powder

“…In this context, and due to the interesting of these fibres for military and civil applications, several studies can be found to improve the impact strength of the systems where they are involved. The low surface energy and chemically inert surface motivated several works to improve their interfacial adhesion with the matrices, but other techniques like stitching, multiaxial warp‐knit fabrics, by fibre hybridisation or the resource to nano‐enhanced resins can be found in the literature.…”

Plasticized Poly(Vinyl Chloride) Filled with Waste Leather Particles

“…It is well known that pre-treatment of the surface of various fillers before their incorporation into polymeric matrices is a very common practice in plastic technology [7][8][9][10]. This procedure aims at the improvement of interfacial characteristics between matrix and filler which is necessary in order to obtain good final properties.…”

SEM Examination and Analysis of the Interface Character in Surface Modified Aramid-Epoxy Composite

“…Background: Surface treatment of fibers for augmenting their affinity to the host polymeric matrix appears to be a promising approach [6][7][8][9]. Treatment of the fibers by plasma involving ammonia, air or argon and various chemical treatment methods are employed in this direction.…”