Acrylic board can be divided into casting board and extrusion board according to production technology, transparent board, translucent board (including dyed board transparent board) and color board (including black and white and color board) according to light transmittance. According to the performance, it is divided into impact-resistant board, ultraviolet board, ordinary board and special board such as high impact-resistant board, flame-retardant board, grinding board, metal effect board, high wear-resistant board, light guide plate and so on. Pellets prepared by suspension polymerization are injection molded on ordinary acrylic plunger or screw injection molding machine. This is a typical process condition of polymethyl methacrylate injection molding. Injection molding products also need post-treatment to eliminate internal stress. The treatment is carried out in a hot air circulating drying oven at 70-80℃, and the treatment time depends on the thickness of the product, which usually takes about 4 hours.