Uniform large particles (millimeter class) of acid poly ionic liquid (PIL-A) were synthetized, and characterized by FT-IR, XRD, TGA/DCS, and SEM. Thermostability and mechanical strength of PIL-A are much higher than that of commercial resin. Its catalytic properties were investigated through the esterification of methacrylic acid and methanol as the objective reaction. Results showed that the catalytic activity of PIL-A was higher than that of commercial resin. The optimum reaction conditions were as follows: 5 wt% catalyst, 95 degrees C reaction temperature, 3 h reaction time, and methacrylic acid to methanol mole ratio of 1:1.2. The yield of methyl methacrylate is 100%, under optimum reaction conditions. The catalytic activities of PIL-A with different esterifications were also investigated. PIL-A had a higher catalytic activity to different esterification. The catalytic activity of PIL-A did not decrease after it was reused for five times. Continuous reaction to methyl methacrylate (MMA) with a fixed bed reactor was further investigated. The percentage of MMA in the product was >96%. (C) 2015 Elsevier B.V. All rights reserved.