polymethacrylates

Polymethacrylates are polymers derived from methacrylate monomers, featuring a methacrylate ester group attached to a carbon backbone. The most widely known member is polymethyl methacrylate (PMMA), commonly called acrylic or acrylic glass, but the family includes many other methacrylate polymers.

They are prepared by addition polymerization of methacrylate monomers such as methyl methacrylate (MMA), ethyl methacrylate, and hydroxyethyl methacrylate. Polymerization methods include bulk, solution, suspension, and emulsion polymerization, typically via free-radical initiation. Copolymerization and crosslinking with di- or multi-functional methacrylates allow tuning of properties and glass transition temperature.

Properties: Polymethacrylates are often colorless, optically clear, and exhibit good weatherability with stabilizers. Tg values vary by monomer; PMMA has a Tg around 105°C and is typically rigid at room temperature, though flexibility can be introduced by comonomers or plasticizers.

Applications: PMMA is widely used for optical lenses, glazing, signage, and dental and medical resins, as well as coatings and adhesives. Polymethacrylates are also employed in dental composites and bone cements in some formulations, and as components in specialty coatings and electronics encapsulation. Hydrogels based on hydroxyethyl methacrylate form contact lenses and biomedical devices.

Variants: The family includes polyethyl methacrylate and other methacrylate-based copolymers. Property tuning is achieved by varying side chains, molecular weight, copolymer composition, and degree of crosslinking. PMMA is the prototypical polymethacrylate; many derivatives serve diversified applications.