LIE Home • Issue Contents

Laser Surface Engineering of Nylon 6.6 and the Effects Thereof on Adhesion and Biomimetic Apatite Coating Formation
D.G. Waugh and J. Lawrence

Within the field of bioengineering, simulated body fluid (SBF) has been widely implemented as a technique to screen for the bioactivity of materials. Of significance, SBF can be used in the biological industry to promote the adhesion of apatite coatings to assist with making materials more biomimetic. CO2 and KrF excimer lasers were used for the surface engineering of nylon 6,6 to modulate apatite formation following immersion in SBF for 14 days. Following CO2 laser surface engineering the surface roughness increased to a maximum Ra and Sa of 1.3 and 4.4 μm, respectively; whilst a maximum increase in surface oxygen content of 5.6 at.% was observed. CO2 laser-induced surface modifications gave rise to a modulation in the wettability characteristics such that the contact angle, θ, decreased for whole area processed samples and increased for patterned samples. For the KrF excimer laser surface engineered samples it was found that Sa increased by up to 1.5 μm when compared to the as-received sample. It was seen for all samples that calcium phosphate formed on each surface following 14 days emersion in SBF. An increase in mass for the laser processed samples indicated that these modified surfaces gave rise to an accelerated formation of apatite when compared to the as-received sample. This, along with strong correlations between θ, the surface energy parameters and the calcium phosphate formation (for whole area processed samples) highlights the potential for this surface treatment technique for predicting and enhancing the bone forming ability of laser processed materials.

Keywords: CO2 laser, KrF excimer laser, Nylon 6.6, simulated body fluid (SBF), surface engineering, wettability, adhesion, biomimetic apatite coatings

Full Text (Open Access)