title: Reinforcement of nylon 6 with functionalized silica nanoparticles for enhanced tensile strength and modulus.
abstract: Pristine and functionalized silica (SiO(2)) nanoparticles were dispersed into nylon 6 and drawn into filaments through melt extrusion. The loading fraction of particles in both cases was 1.0 wt%. Fourier transform infrared (FTIR) studies revealed that reinforcement of pristine silica nanoparticles enhances the bond strength of each of the three basic bonds of nylon 6 namely, hydroxyl, amide, and carbonyl. As a result, the improvement over neat nylon in strength and modulus was 36% and 28% respectively, without any loss of fracture strain (80%). A silane coupling agent was then used through wet chemical treatment to functionalize silica nanoparticles. Functionalization induced an additional covalent Si-O-Si (siloxane) bond between silica particles and nylon backbone polymer while the enhancement in the basic bonds was retained. FTIR and x-ray photoelectron spectroscopy (XPS) studies confirmed the formation of the siloxane bond. This added chemical bond resulted in 76% and 55% improvement in tensile strength and modulus, and still retained 30% fracture strain. Calculation of the upper bound on Young's modulus indicates that one can reach within 5% of the bound with pristine silica particles, but it is exceeded by 15% when particles are functionalized.
authors.affiliation: Department of Ocean Engineering, Florida Atlantic University, Boca Raton, FL 33431, USA.
authors.forename: Hassan
authors.initials: H
authors.lastname: Mahfuz
authors.forename: Mohammad
authors.initials: M
authors.lastname: Hasan
authors.forename: Vinod
authors.initials: V
authors.lastname: Dhanak
authors.forename: Graham
authors.initials: G
authors.lastname: Beamson
authors.forename: Justin
authors.initials: J
authors.lastname: Stewart
authors.forename: Vijaya
authors.initials: V
authors.lastname: Rangari
authors.forename: Xin
authors.initials: X
authors.lastname: Wei
authors.forename: Valery
authors.initials: V
authors.lastname: Khabashesku
authors.forename: Shaik
authors.initials: S
authors.lastname: Jeelani