Improvement of Interfacial Adhesion between UHMWPE Fiber and Epoxy Matrix Using Functionalized Graphitic Nanofibers

Abstract

Ultra high molecular weight polyethylene (UHMWPE) fiber has advanced mechanical properties and excellent physical properties that include high effectiveness for cosmic radiation shielding, which is valuable for outer space missions. Unfortunately, poor interface in UHMWPE fiber—polymer composites hinders the structural integrity and safety, and restricts its effectiveness for the radiation shielding. In this study, we focus on the improvement of the adhesion property between the UHMWPE fiber and resin matrix by developing a nano-epoxy matrix through making a modification on the matrix with reactive graphitic nanofibers (r-GNFs). The interfacial adhesion between UHMWPE fiber and the nano-epoxy matrix with low concentrations of r-GNFs (0.15, 0.30, and 0.50 wt% ) is characterized by analyzing load—displacement curves from microbond tests. Study results show that crack initiation force, debonding force, debonding energy, and friction energy from the microbond tests increase considerably, due to the effective improvement of interfacial adhesion property by the nano-epoxy matrix. One-dimensional shear-lag analysis is applied for theoretical calculations. Calculated results on ultimate adhesive strength and external stress show agreement with the experimental results. Study results reveal that the nano-matrix with 0.30 wt% of r-GNFs is the most effective to improve adhesion properties between UHMWPE fiber and the epoxy.

Nanocomposite coatings for healing surface defects of glass fibers and improving interfacial adhesion

“…One recent proposal is that the functionalized carbon material (e.g. CNT or nanocarbon fiber) within the coating is reactive with the reinforcement as well as the matrix material [32,33]. Besides, the coating with clay results in a much less degradation due to limited access of the aggressive alkali solution, which consequently increase the frictional component of bond.…”

Cosmic radiation shielding tests for UHMWPE fiber/nano-epoxy composites

“…The previous research indicated that such nano-matrices with covalent bond between the nanofibers and polymer resins had greatly enhanced thermal and mechanical properties by synthesis of super molecular structures containing nanofibers, including the proposed strengthening mechanism [17][18][19][20][21][22][23][24][25][26]. The results on the nano-matrices showed that the nano-epoxy has very low nanofiber concentration (0.3 wt%) and interestingly, it showed lower surface energy and viscosity over the pure epoxy [21].…”

“…The nanoscale GNFs with controlled lengths, as the polymer resin molecule's side groups, could enhance mechanical properties drastically for the polymer matrices. In addition, fabrication of reactive nano-modified polymer resin can result in improved interfacial adhesion with the conventional fibers in the macro composites [14][15][16][17][18][19][20][21][22][23][24][25][26].…”

“…Moreover, the reactive functional group led to the formation of a special interface with good adhesion, enhancing the properties of the resulting composites [14][15][16][17][18]. Although the matrix cannot form chemical binding with UHMWPE fibers, this reactive nano-matrix led to good wetting and adhesion to the UHMWPE fiber surface [21,22,24]. For developing high properties of nano-epoxy, we have developed solutions to the key problems including (1) strong interaction between graphitic nanofibers and epoxy resin through further treatment to achieve covalent bonding level; (2) uniform dispersion of the graphitic nanofibers in a polymer; and (3) curing mechanism for optimization of cure cycles [15,16].…”

Free‐Standing All‐Nanoparticle Thin Fibers: A Novel Nanostructure Bridging Zero‐ and One‐Dimensional Nanoscale Features

“…Long-lasting impacts of these 1D features are being generated in multiple fields. For example, nanotubes could be used as scanning probes to provide unprecedented resolution to scanning probe microscopy, [4,5] continuous nanofibers can be efficient intermediate layers in nanocomposites, [6,7] and functional nanobelts demonstrating an electromechanical coupling effect can be potential candidates to power future nanosystems. [8][9][10] While nanoparticles or nanodots qualify as 0D structures and also have peculiar electronic or optoelectronic properties, their role as building blocks for higher-order subjects is one of their most prominent features.…”