本研究以二階段溶脹法(Two-step Swelling)來製備出粒徑約10 μm且具有高交聯結構之均一粒徑聚(甲基丙烯酸甲酯/乙二醇二甲基丙烯酸酯)(MMA/EGDMA)微球，首先利用分散聚合法(Dispersion polymerization)合成均一種子微球，再進一步利用二階段溶脹法增加其粒徑與交聯度進而達到耐溶劑、熱穩定性佳等性質。 在分散聚合法中，可以藉由改變溶劑含水比例及單體含量而製備出粒徑範圍3.5 μm到10.2 μm的高分子微球，而考量到粒徑大小及均一度，選擇以溶劑之水含量為20 wt%及添加單體10 g所合成之種子微球來進行後續第二階段的合成，其粒徑為5.2 μm、Cv %為 5.9 %。 二階段溶脹聚合法中，在系統中共添加5.2 μm種子微球0.1 g下，可藉由添加適當比例的助溶脹劑(環己烷)、單體(MMA或EGDMA)及水相抑制劑(亞硝酸鈉)來製備均一粒徑的PMMA或poly(MMA-co-EGDMA)微球。在添加0.1 g助溶脹劑(環己烷)、10 g單體(MMA)及0.2 g水相抑制劑(亞硝酸鈉)下可得到均一粒徑且粒徑大小為11.6 μm的PMMA微球。另一方面，一樣添加0.1 g助溶脹劑(環己烷)及0.2 g水相抑制劑(亞硝酸鈉)下，藉由改變上述單體的添加比例為4.8 g MMA及1.2 g EGDMA，可得到均一粒徑且粒徑大小為10.9 μm的poly(MMA-co-EGDMA)微球。經過耐溶劑及熱穩定性質的測試，可發現本研究所製備的poly(MMA-co-EGDMA)高分子微球確實具有良好的耐溶劑性質，而其熱穩定性比起種子或是未添加架橋劑的微球亦有顯著的提升。Highly cross-linked, monodisperse with 10 μm poly(MMA-co-EGDMA) microspheres were fabricated by two-step swelling polymerization. At First, the PMMA seed particle was prepared by dispersion polymerization. Then, using two-step swelling polymerization further to increase the particle size and degree of cross linking. These poly(MMA-co-EGDMA) microspheres could achieve the solvent resistance and thermal stability.In dispersion polymerization, the particle size from 3.5 μm to 10.2 μm can be synthesized by control the water weight fraction and monomer concentration. The optimal PMMA seed particle can be prepared via 20 wt% water weight fraction and 10 g MMA, its particle size is 5.2 μm and Cv value is 5.9 %.In two-step swelling polymerization, the result show that the uniform PMMA or poly(MMA-co-EGDMA) microsphere could be prepared by adding suitable amount of swelling agent (cyclohexane), monomer (MMA or EGDMA), aqueous inhibitor (NaNO2). The uniform 11.6 μm size of PMMA microsphere could be prepared by added 0.1 g swelling agent (cyclohexane), 10 g monomer (MMA) and 0.2 g inhibitor (NaNO2) in the system when added 0.1 g, 5.2 μm size of PMMA seed microsphere. On the other hand, the uniform 10.9 μm size of poly(MMA-co-EGDMA) microsphere could be prepared by added 0.1 g swelling agent (cyclohexane) and 0.2 g inhibitor (NaNO2) by changing the above monomer amount to 4.8 g MMA, 1.2 g EGDMA. The Poly(MMA-co-EGDMA) particle have excellent performance on solvent resistance. Also, the Poly(MMA-co-EGDMA) particle has significantly enhance on thermal stability than the seed particle and non cross-linked particle.
