硅烷偶联剂用量对硼酸铝晶须增强PMMA挠曲强度影响的研究

目的研究硅烷偶联剂用量对硼酸铝晶须增强聚甲基丙烯酸甲酯(PMMA)挠曲强度的影响。方法使用质量分数为1.0%、2.0%、3.0%、4.0%的硅烷偶联剂Z-6030对硼酸铝晶须进行表面处理,未经处理的为对照组。把经过处理的硼酸铝晶须以10%添加量与PMMA混合,合成硼酸铝晶须/PMMA复合材料,制成标准试件5组。最后进行3点弯曲测试并且每组随机选出1个试件进行断面扫描电镜观察。结果5组的抗弯强度分别是67.59±5.35、72.96±4.20、75.52±4.89、71.26±5.94、(68.25±3.43)MPa。当硅烷偶联剂的用量为硼酸铝晶须质量的2.0%时,挠曲强度达到最大。利用SAS统计软件对5组的结果进行均数间的两两比较(Newman-Keuls检验)分析可知,硼酸铝晶须/PMMA复合材料各组间挠曲强度的差异无统计学意义(P>0.05)。断面的电镜扫描可见以2.0%硅烷偶联剂修饰硼酸铝晶须时,晶须与树脂间的结合牢固,且其在基质中分散也良好。结论使用硅烷偶联剂能够提高硼酸铝晶须与PMMA树脂间的结合强度,改善其在树脂基质中的分散性,提高复合材料的物理机械性能,但过多或过少均会影响复合材料的强度。针对本实验所使用的晶须、偶联剂以及偶联化方法,硼酸铝晶须用于增强PMMA时最佳的硅烷偶联剂使用量为2.0%。

Aluminum borate whiskers modified by silane coupling agent to enhance bending force of PMMA

Objective To study the enhancing effects of the bending strength of PMMA after aluminum borate whiskers modified by silane coupling agent. Methods The aluminum borate whiskers were surface-treated by silane coupling agent Z-6030 at 1.0%, 2. 0% ,3.0% ,4.0% ,respectively（ratio） ,while the untreated ones were considered as the control group. Then the five groups of surface-treated whisker were mixed into the resin matrix with the 10 percent filling and five groups of whisker / PMMA composite material were synthesized, and then they were made to the standard size samples. At last, the three-point bending test was made and the fracture surfaces were observed by electron microscopy（SEM）. Results The bending strengths of the five groups were 67.59 ± 5.35,72. 96 ± 4. 20,75.52 ± 4. 89,71.26± 5.94 and （68. 25 ± 3.43 ） MPa, respectively. When the amount of silane coupling agent for the quality of aluminum borate whisker was 2. 0 percent, the bending strength was maximum. Analyzing the results of the 5 groups by comparing the average two by two （ Tukey test） , it was indicated that the bending strength of the five groups was not significantly different（ P 〉 0. 05 ） . The SEM pictures of the groups treated by 2. 0% silane coupling agent showed the combination of resin and whisker has been rely good. Conclusion Silane coupling agent can enhance the strength between aluminum borate whiskers and PMMA interface, but different amounts will have different impact on the bending strength of whisker / PMMA composite material, as too much or too little will cause the interface strength to decline, and it will show the declined bending strength in macro. For this experiment, when the amount of silane coupling agent occupied the aluminum borate whisker＇s mass fraction of 2% ,the enhancing effect was the best,and it showed the largest bending strength of composite material.