One-Step Radiation Grafting of Hydrophilic Polymer Brushes on PDMS through Industrial High-Power Electron Beam Equipment for Multipurpose Applications

Polydimethylsiloxane (PDMS) elastomers are widely utilized as biomaterials; however, their application is constrained by inherent inertness and hydrophobicity, which hinder surface properties such as self-cleaning, antifouling, antifogging, or lubrication. While traditional approaches, such as surface-initiated atom transfer radical polymerization (SI-ATRP), can realize surface hydrophilic modification on the PDMS substrate, they are limited by initiator specificity, strict anaerobic conditions, potential toxicity from metal catalysts, complicated procedures, etc. In this work, we introduce a straightforward one-step, radiation-induced graft polymerization strategy using industrial high-power electron beam equipment to overcome the above limitations. This versatile technique generates free-radical-initiated surface polymerization brushes via a one-step irradiation process, obviating the need for preattached initiators, metal catalysts, or anaerobic conditions. This method enables the convenient modification of PDMS elastomer surfaces with hydrophilic poly(3-sulfopropyl methacrylate potassium salt) (PSPMA) brushes, endowing the material with excellent aqueous lubrication, antifogging, self-cleaning, and antibiofouling properties. In addition to PDMS, other organic polymer substrates, such as poly(methyl methacrylate) (PMMA), polycarbonate (PC), polyethylene (PE), and polyethylene terephthalate (PET), can also be hydrophilically modified using this versatile method, which offers a prospective and continuously preparable strategy for the surface functionalization of biomedical devices such as low-friction catheters, antifogging endoscopes, and antifouling implants.