The density of PMMA is lower than that of glass: the density of PMMA is about 1.15-1.19 g/cm, which is half of glass (2.40-2.80 g/cm) and 43% of metallic aluminum (belonging to light metal).
PMMA has high mechanical strength: PMMA has a relative molecular mass of about 2 million. It is a long-chain polymer and the molecular chain is very soft. Therefore, PMMA has high strength and resistance to stretching and impact. It is 7 to 18 times higher than ordinary glass. There is a heated and stretched plexiglass in which the molecular segments are arranged in a very orderly manner, resulting in a significant increase in the toughness of the material. The nail is nailed into the plexiglass, and even if the nail penetrates, no crack is generated. This kind of plexiglass will not break into pieces after being broken by bullets. Therefore, the stretched PMMA can be used as a bulletproof glass and also as a canopy on a military aircraft.
The melting point of PMMA is lower: PMMA has a melting point of about 130–140 ° C (265–285 ° F), which is much lower than the temperature of about 1000 degrees of glass.
PMMA has a high light transmittance
Visible light: PMMA is currently the most excellent polymer transparent material, with a light transmittance of 92%, which is higher than that of glass.