α-Si_3N_4与SP_1SiO_2熔附条件和填料比例对复合树脂性能的影响

Influence of α-Si_3N_4 and SP_1SiO_2 fusing conditions and filler ratios in properities of dental resin composites

目的:检测α-氮化硅(α-Si_3N_4)与多微孔纳米二氧化硅(SP_1SiO_2)的最佳熔附温度、熔附时间和最佳填料比例,阐明其对复合树脂性能的影响。方法:将α-Si_3N_4晶须和SP_1SiO_2颗粒按质量比5∶1混合,以250℃·h-1的升温速度分别升至500℃、650℃、800℃、950℃和1 100℃,并分别保持10min、30min和3h,即为α-Si_3N_4-SP_1SiO_2熔附体复合树脂组,同时设立SP_1SiO_2颗粒组、α-Si_3N_4晶须组和α-Si_3N_4与SP_1SiO_2混合未熔附组(混合组),选择2种市售复合树脂作为对照组。环己烷溶液处理后与树脂基质按质量分数60%充分混合、聚合制作试样,测试挠曲强度并分析其断面扫描电子显微镜(SEM)形貌。再将配比为2∶1的α-Si_3N_4与SP_1SiO_2混合,最佳熔附条件熔附,环己烷溶液处理后与树脂基质按20%、40%、60%、70%和75%质量分数充分混合、聚合,选择2种市售复合树脂作为对照组,测试挠曲强度并分析其断面SEM形貌。结果:α-Si_3N_4-SP_1SiO_2熔附体复合树脂组800℃、30min时挠曲强度值最大,挠曲强度值均明显高于SP_1SiO_2颗粒组、α-Si_3N_4晶须组、混合组和2个对照组(P<0.05),断面SEM形貌与力学性能相符。α-Si_3N_4-SP_1SiO_2熔附体复合树脂挠曲强度随着α-Si_3N_4与SP_1SiO_2熔附体填料比例从20%增加至60%逐渐增大(P<0.05),填料比例为60%~70%时挠曲强度值增加不明显,填料比例为70%~75%时挠曲强度值减小,填料比例为60%和70%时复合树脂的挠曲强度值均明显高于填料比例为20%、40%和75%时复合树脂及对照组,断面SEM形貌与力学性能相符。结论:α-Si_3N_4与SP_1SiO_2最佳熔附条件是800℃处理30min;α-Si_3N_4与SP_1SiO_2熔附体填料最佳比例为70%。

Objective:To detect the optimal fusing temperature,the fusing time and the best filler ratio ofα-Si 3N 4 and SP 1SiO 2,and to clarify their influence in the properities of dental resin composites.Methods:Theα-Si 3N 4 crystalline were mixed with SP 1SiO 2 particle at the ratio of 5∶1(Wt%),and then were sintered under 500℃,650℃,800℃,950℃and 1 100℃at a rise rate of 250·h-1 and maintained for 10 min,30 min and 3 h,respectively(used asα-Si 3N 4-SP 1SiO 2 groups).SP 1SiO 2 particle,α-Si 3N 4 crystalline,mixed and non-fusedα-Si 3N 4 a nd SP 1SiO 2(mixed)groups were set up,and two commercially available resin composites were selected and used as control groups.And they were fully mixed with the resin matrix in 60%(Wt%)after the treatment of cyclohexane solution to make the samples.The flexural strength of specimen was tested and the morphology of section under SEM was analyzed.Thenα-Si 3N 4 was mixed with SP 1SiO 2 in a ratio of 2∶1.It was fused under the optimal fusing conditions.After the treatment of cyclohexane solution,it was mixed and polymerized with the resin matrix in the proportions of 20%,40%,60%,70%and 75%(Wt%),and two kinds of commercially available resin composites were selected and used as control groups.The flexural strength of specimens was tested and the morphology of section under SEM was analyzed.Results:The maximum flexural strength value inα-Si 3N 4-SP 1SiO 2 groups was at 800℃and 30 min(P>0.05);the flexural strength value was significantly higher than those in SP 1SiO 2 group,α-Si 3N 4 crystalline group,mixed group and two control groups(P<0.05),and the morphology of section SEM was consistent with the mechanical properties.The flexural strengths of resin composites were increased gradually with the increasing of filler ratios ofα-Si 3N 4 and SP 1SiO 2 fusion from 20%to 60%(P<0.05);the flexural strength values of resin composites with the proportion of 60%-70%were not increased significantly,the flexural strength values of resin composites with the proportion of 70%-75%were decreased,and the flexural strength values of the resin composites with the proportion of 60%and 70%were significantly higher than those of resin composites with the proportions of 20%,40%,75%and control groups;the morphology of section under SEM was consistent with the mechanical properties.Conclusion:The optimum fusing condition forα-Si 3N 4 and SP 1SiO 2 is 800℃for 30 min,and the best filler ratio ofα-Si 3N 4 and SP 1SiO 2 is 70%.