有机蒙脱土增强的纳米义齿基托树脂中残留甲基丙烯酸甲酯含量的测定及分析

目的:研究纳米义齿基托树脂在使用有机蒙脱土(OMMT)增强义齿基托的机械性能后,材料中OMMT的含量对固化后材料中残留甲基丙烯酸甲酯(MMA)含量的影响,并确定合适的OMMT的混合比例,使固化后材料的机械性能得到较好提高的同时残留MMA含量也在可接受的范围内。同时对该固化材料在水中MMA的释放量进行测定。方法:材料中残留的MMA用丙酮进行抽提,材料在水中释放的MMA用氯仿萃取。抽提液和萃取液用气相色谱测定其中MMA的浓度。结果:OMMT的量对固化材料中残留MMA的量有显著性影响(P<0.05),随着固化材料中OMMT的量的增加,残留MMA的量也逐渐增加。当OMMT的混合比例为1wt%时,不仅材料的机械性能的到了较好提升,材料中的残留MMA的量也在YY0270-2003标准(最大2.2wt%)范围内。放置于37℃水中7d后,MMA的释放量随时间的增加趋于稳定;观察3周,MMA水中释放量小于用丙酮抽提时所测得的残留MMA量。结论:固化材料中MMA的含量随着OMMT含量的增加而增加。材料在水中的MMA释放量小于用丙酮抽提时所测得的MMA量。

Measurement and Analysis of Residual MMA Monomer Concentration in OMMT Reinforced Denture Base Polymers after Heat-polymerized

Objective:To select a proper mixed proportion of OMMT,which was introduced into the polymers,in order to maintain the amount of residual MMA monomer acceptable and the mechanical properties of the resins improved at the same time.Methods:Specimens of the OMMT reinforced denture base were prepared in the form of thin polymer disks.Residual MMA monomer was extracted from the disks with acetone and from the storage water with chloroform.Concentrations of MMA monomer were determined by gas chromatography(GC).Results:OMMT gave a significant increase of residual MMA monomer concentration(P<0.05).As the content of OMMT increased,the amount of residual MMA monomer in the polymers increased.If the mixed proportion of OMMT was 1wt%,the amount of residual MMA monomer in the cured polymers complied with the national standards(<2.2wt%)and the mechanical properties of the resins were better improved.After 7 days in water,the amount of MMA released from the polymers tended to stable.After observed 3 weeks in water,MMA monomer was found less in water than that extracted with acetone.Conclusion:The current study suggested that the concentration of residual MMA monomer increased as the content of OMMT increased in the polymers.The residual MMA monomer released in water was found less than that extracted with acetone.