Synthesis of poly(fluorinated styrene)-block-poly(ethylene oxide) amphiphilic copolymers via atom transfer radical polymerization: Potential application as paper coating materials

Background: The surface of a substrate which comprises a fibrous material is brought into contact with a type of amphiphilic block copolymer which comprises hydrophilic/hydrophobic polymeric blocks. These amphiphilic copolymers have been synthesized by atom transfer radical polymerization (ATRP) technique. The atom transfer radical polymerization of poly(2,3,4,5,6-pentafluorostyrene)-block-poly(ethylene oxide) (PFS-b-PEO) copolymers (di- and triblock structures) with various ranges of PEO molecular weights was initiated by a PEO chloro-telechelic macroinitiator. The polymerization, carried out in bulk and catalysed by copper(I) chloride in the presence of 2,2′-bipyridine ligand, led to A-B-A amphiphilic triblock and A-B amphiphilic diblock structures. Results: With most of the macroinitiators, the living nature of the polymerizations led to block copolymers with narrow molecular weight distributions (1.09 < M_w/M_n < 1.33) and well-controlled molecular structures. These block copolymers turned out to be water-soluble through adjustment of the PEO block content (>90 wt%). Of all the block copolymers synthesized, PFS-b-PEO(10k)-b-PFS containing 10 wt% PFS was found to retard water absorption considerably. Conclusion: The printability of paper treated with the copolymers was evaluated with contact angle measurements and felt pen tests. The adsorption of such copolymers at the solid/liquid interface is relevant to the wetting and spreading of liquids on hydrophobic/hydrophilic surfaces.