Modification of properties

Pure poly(methyl methacrylate) homopolymer is rarely sold as an end product, since it is not optimized for most applications. Rather, modified formulations with varying amounts of other comonomers, additives, and fillers are created for uses where specific properties are required. For example,

• A small amount of acrylate comonomers are routinely used in PMMA grades destined for heat processing, since this stabilizes the polymer to depolymerization ("unzipping") during processing.
• Comonomers such as butyl acrylate are often added to improve impact strength.
• Comonomers such as methacrylic acid can be added to increase the glass transition temperature of the polymer for higher temperature use such as in lighting applications.
• Plasticizers may be added to improve processing properties, lower the glass transition temperature, or improve impact properties.
• Dyes may be added to give color for decorative applications, or to protect against (or filter) UV light.
• Fillers may be added to improve cost-effectiveness.

Poly(methyl acrylate)

Main article: Poly(methyl acrylate)

The polymer of methyl acrylate, PMA or poly(methyl acrylate), is similar to poly(methyl methacrylate), except for the lack of methyl groups on the backbone carbon chain.^[24] PMA is a soft white rubbery material that is softer than PMMA because its long polymer chains are thinner and smoother and can more easily slide past each other.

Uses