Zheng Tiancheng, Ni Xiuyuan
J Nanosci Nanotechnol. 2018 Oct 1;18(10):6815-6822. doi: 10.1166/jnn.2018.15522.
We prepared a new size-stable UV-cured material by loading a radical scavenger, 4-methoxyphenol (MEHQ), into halloysite nanotubes (HNTs) to improve the size-stability of UV-cured products. Loading the MEHQ into halloysite nanotubes was intended to protect the curing reaction from the typical inhibitive influence of a radical scavenger. After the curing process, heating treatment was performed on the cured products to accelerate the release of MEHQ from the halloysite lumen. The Brunauer-Emmett-Teller tests and transmission electron micrographs showed that MEHQ was successfully loaded into the halloysite lumen. The photopolymerization kinetic curves of composites revealed that adding the MEHQ-loaded halloysite nanotubes (HNTs-M) into UV-cured materials enabled faster photopolymerization rate than adding a simple mixture of HNTs and MEHQ. With MEHQ loaded in HNTs, the inhibition influence of MEHQ could be reduced. The results of the size-stability test showed that composites with HNTs-M underwent lower deformation during daily use than neat cured materials. In particular, the volume shrinkage of the composites with 8 wt% HNTs-M in daily use was decreased by 51.3%. The results of the release experiment showed that the release rate of MEHQ could be increased through heating treatment. This method may be used to improve the size-stability of UV-curable materials in the future.
我们通过将自由基清除剂4-甲氧基苯酚（MEHQ）负载到埃洛石纳米管（HNTs）中，制备了一种新型尺寸稳定的紫外线固化材料，以提高紫外线固化产品的尺寸稳定性。将MEHQ负载到埃洛石纳米管中旨在保护固化反应免受自由基清除剂典型的抑制影响。固化过程完成后，对固化产物进行热处理，以加速MEHQ从埃洛石管腔中的释放。布鲁诺尔-埃米特-泰勒测试和透射电子显微镜图像表明，MEHQ成功负载到了埃洛石管腔中。复合材料的光聚合动力学曲线显示，向紫外线固化材料中添加负载MEHQ的埃洛石纳米管（HNTs-M）比添加HNTs和MEHQ的简单混合物能实现更快的光聚合速率。由于MEHQ负载在HNTs中，MEHQ的抑制影响得以降低。尺寸稳定性测试结果表明，与纯固化材料相比，含有HNTs-M的复合材料在日常使用中变形更小。特别是，在日常使用中，含8 wt% HNTs-M的复合材料的体积收缩率降低了51.3%。释放实验结果表明，通过热处理可以提高MEHQ的释放速率。这种方法未来可能用于提高可紫外线固化材料的尺寸稳定性。
