Molecularly imprinted poly(N-vinyl imidazole) based polymers grafted onto nonwoven fabrics for recognition/removal of phloretic acid

• Molecularly imprinted matrices (MIP) of phloretic acid were prepared by radiation polymerization of N-vinyl imidazole.
• Polymerization and crosslinking were achieved as a thin grafted layer on the surface of PE/PP nonwoven fabric.
• Binding performance of MIP graft layers were found to show an imprinting factor of 2.41 for this template.
• Grafted layers were characterized by SEM and PALS techniques.
• Binding isotherms were found to follow double Langmuir isotherms.

A solution of N-vinyl imidazole (VIm), ethylene glycol dimethylacrylate (EGDMA), and phloretic acid (p-hydroxyphenylpropionic acid, HPPA) as functional monomer, crosslinker and template, respectively, were used to graft molecularly imprinted polymer (MIP) onto polyethylene/polypropylene (PE/PP) nonwoven fabric via gamma radiation at room temperature. Control grafted films were also synthesized using the same procedure in the absence of HPPA. Binding performance of the MIP grafts was investigated for different template molecule concentrations and contact time. An imprinting factor for the sample prepared at 5 kGy dose was determined as 2.41 for 50 ppm HPPA solution for 3-h incubation. MIP graft layers were investigated by positron annihilation lifetime spectroscopy (PALS) as well as SEM.