同时具有高透明、高折光率及高阻燃性环氧树脂设计合成

High refractive index and transparent epoxy resin (EP) is widely used in many fields, such as special adhesive, LED packaging, art ware and molding. However, inflammability is one of the main drawbacks of the EP. Unfortunately, traditional epoxy resin (EP) usually loses its transparency and refractive index once it encounters the requirement of flame retardance. So to enhance the flame retardance and simultaneously improve the refractive index and transparent performance of EP is an important aspect. In this project, the sulfur and phosphorus elements were introduced to aliphatic polyamine through diphenylphosphinic chloride (DPPC) and sulfourea, then a series of transparent flame-retardant curing agents containing polyamine with halogen-free flame retardant elements were designed and prepared. Based on the chemical nature of polyamine structure which can participate in the curing reaction of epoxy through chain-extension or cross-linking reaction, reactive phosphorus- sulfur elements are introduced to the actualize inherent flame EP. Meanwhile, due to the introduction of sulfur, the Flame retardant efficiency of curing EP increased, but also the refractive index could be improved. Reasonable mechanisms of flame retardant, transparency and refractive index will be researched and proposed. The work will provide a novel insight for designing and preparing of the other materials with reactive flame-retardant system.

具有高透明及高折光率的环氧树脂广泛应用于特种粘合剂、LED灯、工艺品和特殊模具模块等领域，但其极易燃烧。环氧树脂的阻燃改性往往伴随着透明性和折光率的显著降低甚至消失，故制备兼具高透明、高折光率与高阻燃性的环氧树脂成为了亟需解决的难题。本项目拟通过缩合脱氨反应将硫脲引入液体脂肪族多胺中，再与二苯基磷酰氯反应，合成兼具无卤阻燃元素与多胺基结构的液态透明无卤反应型阻燃固化剂。利用阻燃固化剂分子中的多胺基结构通过扩链/交联固化环氧树脂。引入的硫元素即可与磷协同阻燃，同时也可显著提高环氧树脂的折光率，并保持环氧树脂的高透明性，从而解决环氧树脂阻燃性改善而透明性和折光率显著下降这一难题。通过探讨该阻燃固化剂的结构与用量对环氧树脂阻燃性能、透明性与折光性能的影响机制，揭示其组成-结构-性能之间的构效关系，为类似多功能反应型阻燃剂的分子设计和制备提供一种新思路。

环氧树脂的无卤阻燃改性往往伴随着透明性和折光率的显著降低甚至消失，本项目基于硫元素的高折光率、磷元素的阻燃及多胺固化剂的扩链/交联功能，设计制备了含磷硫的液体反应型阻燃固化剂（DPPEI、DPTA、PTDP和DPTTA），进而获得了一系列含磷硫的环氧树脂。研究结果表明该系列阻燃固化剂的加入不仅可以提高环氧树脂的阻燃性能和折光率，且能维持原环氧树脂的透明性和力学性能。在PTDP添加量为30wt%时，环氧树脂在可见光范围内透过率仍达到90%，折光率从1.495升到1.591，同时减热抑烟效果显著；揭示了不同结构类型的阻燃固化剂对环氧树脂阻燃透明机制；探索出了“兼具高透明、高折光率与高阻燃性的环氧树脂”的有效途径。在本项目的执行过程中，共发表高水平论文6篇，其中ESI高被引1篇，国际会议论文2篇，相关专利授权2项。本项目的开展为类似多功能反应型阻燃剂的分子设计和制备提供一种新思路。