Polymethyl methacrylate end groups contain acetal structures. Upon heating to approximately 100°C, they can gradually depolymerize from the acetal site on the end group, thus exhibiting low heat resistance. When heated to around 170°C, they can undergo automatic oxidation reactions at any point in the molecular chain, releasing formaldehyde. In the presence of high temperature and oxygen, formaldehyde is oxidized to formic acid, which has an automatic catalytic effect on the degradation of polymethyl methacrylate, thereby accelerating the degradation process. Therefore, heat stabilizers, antioxidants, and formaldehyde absorbents are often added to homopolymethyl methacrylate resins to meet the requirements of molding and processing. Due to the presence of a certain amount of C-C bonds in the copolymer methyl methacrylate molecular chain, it can prevent the oxidation degradation of the polymethyl methacrylate molecular chain, making the copolymer much better in terms of heat stability compared to the homopolymer. However, whether it is homopolymethyl methacrylate or copolymer methyl methacrylate, sufficient attention should be given to their poor heat and thermal-oxidative stability during processing and application.主要用于 gear, bearing, automotive parts, machine tools, and instrument interiors as structural components.