多成分掺杂甲基丙烯酸基光致聚合物的制备及其体全息存储稳定性的研究

Preparation and volume holographic storage stabilty of multi-component doped P(MMA-co-MAA)photopolymer

制备了多成分掺杂甲基丙烯酸基光致聚合物,对其全息存储性能进行了实验研究。聚合物样品由SiO2纳米粒子、有机金属化合物ZnMA、菲醌(PQ)、甲基丙烯酸甲酯与甲基丙烯酸共聚基底(P(MMA-co-MAA))组成。聚合物基底的热致聚合与光敏成分在相干光作用下的光致聚合过程是分开进行的,从而使聚合物材料具有可忽略的收缩性。为了让多种掺杂成分能够均匀的分布于样品中,制备过程采用了振荡混合方法。特殊的制备方法使样品具有可忽略的收缩和良好的光学性能。制备了厚为1 mm的SiO2/ZnMA/PQ/P(MMA-co-MAA)样品,与传统的PQ/PMMA材料进行比较。实验测试了SiO2/ZnMA/PQ/P(MMA-co-MAA)聚合物材料的全息散射损失情况,并定量描述了复用光栅的长期存储稳定性。经过3 300s的暗增长过程后,复用光栅的衍射效率均匀性得到了显著改善。实验结果表明,全息散射并没有因为多种成分的引入而显著增加,而共聚基底P(MMA-co-MAA)能够显著提高全息光栅的存储稳定性。多成分掺杂样品中记录的光栅衰减常数为6.4×104 s,远大于传统PQ/PMMA聚合物中的2×104 s,衰减时间越长,意味着材料中光栅的存储稳定性越好。

Multi-component dispersed poly （methyl methacrylate-co-methacrylic acid） photopolymer was prepared and its holographic characteristics are investigated experimentally. The sample is composed of SlOe nanoparticles,ZnMA organometallic components, PQ photosensitizer and P（MMA-co-MAA） matrix. The strategy to inhibit the shrinkage of photopolymer is used to separate the photopolymerizatoin during exposure from thermal polymerization of host matrix. The ultrasonic oscillation method is used to uniformly mix several components in the sample. The neglectable shrinkage and excellent optical properties are attributed to the special preparation method. The SiO2/ZnMA/PQ/P（MMA-co-MAA） sample with thickness of 1 mm was prepared in the experiment. Typical PQ/PMMA sample with the same thickness was prepared for comparative experiments. The holographic scattering losses of samples were measured and holographic storage stability is described quantitatively. After a period of 3 300 s, the uni- formity of diffration efficiency in multiplexing is evidently improved. The experimental results indicate that the increase of scattering loss can be neglected. Moreover,the improvement of stability is achieved by the P（MMA-co-MAA） matrix The decay time constant of grating in multi-component doped sample is 6.4 × 10^4 s. This value is much bigger than 2 × 10^4 s in typical PQ/PMMA material. The multi-com- ponent dispersed polymer maybe provide a significant foundation to obtain holographic materials with high stability and capability.