双柔性链段自乳化环氧树脂固化剂的分子构建及涂层性能

Molecular construction and coating properties of self-emulsifying epoxy resin curing agent with double flexible segments

摘要:

热固性环氧树脂因优异的综合性能,在精细高分子涂层领域得到了广泛的应用。然而,如何通过双组份结构设计制备兼顾力学、疏水性和耐盐雾特性的环氧树脂涂层仍是一个重要挑战。本文将三乙烯四胺(TETA),双酚A型环氧单体(E51)以及聚醚柔性链段(DEG501)经过开环加成,得到单柔性链段固化剂(TED),再以二聚酸柔性链段(DA)改性TED得到双柔性链段固化剂(DTED),分别用固化剂TED和DTED对环氧单体E51进行固化,得到基于单柔性链段的环氧树脂E51-TED以及基于双柔性链段的环氧树脂E51-DTED。利用FT-IR、₁^{H NMR}、SEM、热重分析仪、万能试验仪、盐雾机以及接触角测定仪对两种环氧树脂的结构和性能进行了表征。结果表明,环氧树脂E51-DTED其玻璃化转变温度达到123 ℃,最大抗压强度可达46.564 MPa,水接触角最大可达到95.7°,耐盐雾最多可达到96 h,在水中的体积溶胀率可达到0.33%,双柔性链段的引入使得环氧树脂具有较好的热稳定性,优异的力学性能,良好的疏水性,耐水性以及耐盐雾性能。

Abstract:

Thermosetting epoxy resins have been widely used in the field of fine polymer coatings due to their excellent comprehensive property. However, it is still an important challenge to fabricate epoxy resin coatings with mechanical, hydrophobic, and salt spray resistance properties through two-component structure design. In this paper, triethylenetetramine (TETA), epoxy monomer E51 and polyether flexible chain segment (DEG501) were added through ring opening reaction to obtain single flexible segment curing agent (TED), and then modified with dimer acid flexible segment (DA) TED to obtain double flexible segment curing agent (DTED). Subsequently, epoxy monomer E51 was reacted with curing agent TED and DTED respectively, to obtain epoxy resin E51-TED based on single flexible segment and epoxy resin E51-DTED based on double flexible segment . The structures and properties of the two epoxy resins were characterized by FT-IR, _¹H NMR, SEM, TEM, thermogravimetric analyzer, universal tester, salt spray machine and contact angle tester. The results show that the glass transition temperature of epoxy resin E51-DTED reaches 123 °C, the maximum compressive strength can reach 46.564 MPa, the maximum water contact angle can reach 95.7°, and the salt spray resistance can reach up to 96 h, the volume swelling rate in water can reach 0.33%. The introduction of dual flexible segments enables the epoxy resin to exhibit excellent thermal stability, outstanding mechanical properties, good hydrophobicity, water resistance and resistance to salt spray.