氟碳链修饰酰基氧化膦长波吸收光引发剂的研究

Study on Fluorocarbon Chain Modified Acyl Phosphine Oxide as Long Wavelength Absorbing Photoinitiator

以2,4,6-三甲基苯甲酰基膦酸乙酯(TPO-L)、全氟辛基乙基醇、草酰氯为原料合成了2,4,6-三甲基苯甲酰基膦酸全氟辛基乙酯(TPO-F)光引发剂。利用核磁共振(1 HNMR、19FNMR)和红外光谱(FT-IR)对TPO-F进行结构表征;通过紫外吸收光谱测定了TPO-F的最大吸收波长,与TPO-L的吸收曲线类似,但长波范围的摩尔吸光度略高;光引发剂溶液分层吸光度测试表明,TPO-F具备显著迁移富集特征,有助于表面氧阻聚的解决。在氮气氛围下,通过光-差示扫描量热仪(Photo-DSC)对TPO-F进行了光聚合反应动力学研究,探究了光强、引发剂浓度对单体双键的转化率和最大聚合速率的影响。在空气氛围下,通过差示扫描量热仪(DSC)考察了光引发剂的抗氧阻聚性能。研究表明,TPO-F光引发效率显著高于TPO-L,二者组合可进一步提升光引发效率。本研究为后续UV LED光固化技术中存在的氧阻聚瓶颈问题提供了解决途径。

2,4,6-Trimethylbenzoyl phosphonic acid perfluorooctyl ethyl ester(TPO-F),synthesized with ethyl 2,4,6-trimethylbenzoylphosphonate(TPO-L)and perfluorooctylethyl alcohol and oxalyl chloride.It was characterized by 1HNMR,19 FNMR and FT-IR.The UV absorption spectra of TPO-F were similar to those of TPO-L,the molar absorbance of maximum wavelength is slightly higher.It was confirmed that TPO-F could rapidly immigrate to formulation surface with the UV absorption depth-resolution following of TPO-F solution.The photopolymerization kinetics of acrylate monomer with TPO-L,TPO-F as photoinitiator was investigated by(Photo-DSC).TPO-F exhibits moderate photoinitiation efficiency approximating to TPO-L under nitrogen atmosphere,but improved photoinitiation efficiency for TPOL-F and its combination with TPO-L was resulted under air due to the surface self-concentration effect of TPO-F.Oxygen inhibition effect popularly existing in radical photopolymerization may thus be limited.