A novel class of photochromic copolymer based on spironaphthoxazine (SO) moieties was smoothly prepared through the copolymerization of methyl methacrylate (MMA), butyl acrylate (BA) and SO-based monomer by photopolymerization. Polymerization efficiency was studied by measuring the content of SO in eluents, which decreased with increasing mass ratio of SO in precursor monomer. The incorporated SO moieties endow the copolymers with remarkable photochromic ability. The novelty of this study is that unlike conventional physically blending photochromic polymer, SO moieties were chemically bonded with polymer chain, which is an effective way to prevent the SO from migration, thus increasing the stability and reliability during the long-term application. Moreover, the copolymerization was prepared through UV polymerization in the absence of organic solvent, which is environmentally friendly. Polymer chain flexibility can be well tuned by changing the mass ratio of BA. To make the copolymer more flexible, plasticizer of dibutyl phthalate (DBP) was also introduced. The photochromic ability of the as-prepared films was enhanced with increase in flexibility of polymer chain, which achieved the optimum state when the mass ratios of plasticizer DBP (dibutyl phthalate) and precursor BA (butyl methacrylate) were 20% and 50%, respectively. The thermal stability and tensile strength of the products were characterized by thermogravimetric analysis and electronic universal testing machine, which revealed that these copolymers could be applied as photochromic materials.

中文翻译：

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具有螺恶嗪部分基团的光聚合新型共聚物的光致变色

通过甲基丙烯酸甲酯（MMA），丙烯酸丁酯（BA）和SO基单体的光聚合反应，顺利制备了一种基于螺萘并恶嗪（SO）部分的新型光致变色共聚物。通过测量洗脱液中SO的含量来研究聚合效率，该效率随前体单体中SO的质量比增加而降低。掺入的SO部分使共聚物具有显着的光致变色能力。这项研究的新颖之处在于，与常规的物理共混光致变色聚合物不同，SO部分与聚合物链化学键合，这是防止SO迁移的有效方法，从而提高了长期使用过程中的稳定性和可靠性。此外，该共聚是在不存在有机溶剂的情况下通过UV聚合进行的，这是环境友好的。通过改变BA的质量比，可以很好地调节聚合物链的柔韧性。为了使共聚物更具挠性，还引入了邻苯二甲酸二丁酯（DBP）的增塑剂。制备的薄膜的光致变色能力随着聚合物链柔性的增加而增强，当增塑剂DBP（邻苯二甲酸二丁酯）和前体BA（甲基丙烯酸丁酯）的质量比分别为20％和50％时，达到最佳状态。 。通过热重分析和电子万能试验机对产品的热稳定性和拉伸强度进行了表征，结果表明这些共聚物可以用作光致变色材料。通过改变BA的质量比，可以很好地调节聚合物链的柔韧性。为了使共聚物更具挠性，还引入了邻苯二甲酸二丁酯（DBP）的增塑剂。制备的薄膜的光致变色能力随着聚合物链柔性的增加而增强，当增塑剂DBP（邻苯二甲酸二丁酯）和前体BA（甲基丙烯酸丁酯）的质量比分别为20％和50％时，达到最佳状态。 。通过热重分析和电子万能试验机对产品的热稳定性和拉伸强度进行了表征，结果表明这些共聚物可以用作光致变色材料。通过改变BA的质量比，可以很好地调节聚合物链的柔韧性。为了使共聚物更具挠性，还引入了邻苯二甲酸二丁酯（DBP）的增塑剂。制备的薄膜的光致变色能力随着聚合物链柔性的增加而增强，当增塑剂DBP（邻苯二甲酸二丁酯）和前体BA（甲基丙烯酸丁酯）的质量比分别为20％和50％时，达到最佳状态。 。通过热重分析和电子万能试验机对产品的热稳定性和拉伸强度进行了表征，结果表明这些共聚物可以用作光致变色材料。制备的薄膜的光致变色能力随着聚合物链柔性的增加而增强，当增塑剂DBP（邻苯二甲酸二丁酯）和前体BA（甲基丙烯酸丁酯）的质量比分别为20％和50％时，达到最佳状态。 。通过热重分析和电子万能试验机对产品的热稳定性和拉伸强度进行了表征，结果表明这些共聚物可以用作光致变色材料。制备的薄膜的光致变色能力随着聚合物链柔性的增加而增强，当增塑剂DBP（邻苯二甲酸二丁酯）和前体BA（甲基丙烯酸丁酯）的质量比分别为20％和50％时，达到最佳状态。 。通过热重分析和电子万能试验机对产品的热稳定性和拉伸强度进行了表征，结果表明这些共聚物可以用作光致变色材料。