Surface morphological modification of crosslinked hydrophilic co-polymers by nanosecond pulsed laser irradiation

Abstract

This work reports an investigation of the surface modifications induced by irradiation with nanosecond laser pulses of ultraviolet and visible wavelengths on crosslinked hydrophilic co-polymeric materials, which have been functionalized with 1-vinylimidazole as a co-monomer. A comparison is made between hydrogels differing in the base co-monomer (N,N-dimethylaminoethyl methacrylate and N-[3-(dimethylamino)propyl] methacrylamide) and in hydration state (both swollen and dried states). Formation of craters is the dominant morphological change observed by ablation in the visible at 532 nm, whereas additional, less aggressive surface modifications, chiefly microfoams and roughness, are developed in the ultraviolet at 266 nm. At both irradiation wavelengths, threshold values of the incident laser fluence for the observation of the various surface modifications are determined under single-pulse laser irradiation conditions. It is shown that multiple-pulse irradiation at 266 nm with a limited number of laser shots can be used alternatively for generating a regular microfoam layer at the surface of dried hydrogels based on N,N-dimethylaminoethyl methacrylate. The observations are rationalized on the basis of currently accepted mechanisms for laser-induced polymer surface modification, with a significant contribution of the laser foaming mechanism. Prospective applications of the laser-foamed hydrogel matrices in biomolecule immobilization are suggested.

Effects of Laser Irradiation on Adhesive Tribo-Performance of Eva/Hdpe/Ma-G-Pe/Ommt Blended Polymer Nanocomposites

“…along with various surface treatments like rare earth, plasma, acid and many more have been used in the past to achieve desired surface properties. Irradiation with nanosecond laser pulses of ultraviolet and visible wavelengths on cross-linked hydrophilic co-polymeric materials showed that multiple-pulse irradiation at 266 nm with a limited number of laser shots can be used alternatively for generating a regular micro foam layer at the surface (Primo.,2016). A low-energy electron irradiation method was used to nanocrystalline the topsurface of amorphous carbon film in electron cyclotron resonance plasma system, which induced a lower friction than that of the original pure amorphous film because the electron irradiation gave rise to the formation of sp 2 nano crystallites in the film top-surface within 4 nm thickness (Chen.,2016).…”

Creation of Superhydrophobic and Superhydrophilic Surfaces on ABS Employing a Nanosecond Laser

“…Lasers have been widely used to tune the wettability properties of materials like metal [22,23,24,25,26,27], silicon [28,29], or different polymeric materials [30,31,32]. Various approaches have been employed to change polymer wetting behavior using lasers, in particular, the chemical activation of the surface [33], controlled isomerisation of photoresponsive moieties [34], or nano- and micro-patterning [35,36,37,38].…”

Influence of amine groups in the chemical structure of photochromic dyes on the rheological and mechanical properties of poly(methyl methacrylate) (PMMA)

“…More recently, the modification of polymers and compounds has been used as a method to establish or improve compatibility and/or reactivity between the polymer matrix and the fillers or compounds dispersed in it [10,11]. This enables changes to be made in dielectric [12] electrical and optical [13] properties, absorption of electromagnetic radiation [14], chemical bonding of polymer to metallic nanoparticles [4], compatibilization of polymer blends [6], and in the manufacture of microdevices [15], among others.…”