目的：制备具有不同酸值的甲基丙烯酸甲酯甲基丙烯酸共聚物（ＰＭＭＡｃｏＭＡＡ），研究其理化性质以便评估其结肠靶向性。方法：以ＰＭＭＡｃｏＭＡＡ薄膜为对象，研究薄膜的水渗透性、溶胀性、临界溶解ｐＨ和在不同ｐＨ缓冲液中的稳定性。结果：ＰＭＭＡｃｏＭＡＡ的理化性质差异是它们的酸值不同导致的，ＰＭＭＡｃｏＭＡＡ酸值越小，其临界溶解ｐＨ越大。结论：ＰＭＭＡｃｏＭＡＡ的理化性质取决于它们的酸值大小。 Objective: To prepare methyl methacrylate-methacrylic acid copolymer (PMMA-co-MAA) with different acid value and study its physical and chemical properties in order to evaluate its colon targeting. Methods: The PMMAcoMAA film was used to study the water permeability, swelling, critical solution pH and stability in different pH buffers. Results: The differences of physicochemical properties of PMMAcoMAA were caused by their different acid values. The smaller the PMMAcoMAA acid value, the greater the critical solution pH. Conclusion: The physico-chemical properties of PMMA-co-MAA depend on their acid value.