Jeong Hayun, Jang Keon-Soo
Department of Polymer Engineering, School of Chemical and Materials Engineering, The University of Suwon, Hwaseong 18323, Gyeonggi-do, Republic of Korea.
Polymers (Basel). 2024 Feb 5;16(3):439. doi: 10.3390/polym16030439.
Epoxy resins find extensive utility across diverse applications owing to their exceptional adhesion capabilities and robust mechanical and thermal characteristics. However, the demanding reaction conditions, including extended reaction times and elevated reaction temperature requirements, pose significant challenges when using epoxy resins, particularly in advanced applications seeking superior material properties. To surmount these limitations, the conventional approach involves incorporating organic catalysts. Within the ambit of this investigation, we explored the catalytic potential of metallic powders, specifically bismuth (Bi) and silver (Ag), in epoxy resins laden with various curing agents, such as diacids, anhydrides, and amines. Metallic powders exhibited efficacious catalytic activity in epoxy-diacid and epoxy-anhydride systems. In contrast, their influence on epoxy-amine systems was rendered negligible, attributed to the absence of requisite carboxylate functional groups. Additionally, the catalytic performance of Bi and Ag are different, with Bi displaying superior efficiency owing to the presence of inherent metal oxide layers on its powder surfaces. Remarkably, the thermal and mechanical properties of uncatalyzed, fully cured epoxy resins closely paralleled those of their catalyzed counterparts. These findings accentuate the potential of Bi and Ag metal catalysts, particularly in epoxy-diacid and epoxy-anhydride systems, spanning a spectrum of epoxy-based applications. In summary, this investigation elucidates the catalytic capabilities of Bi and Ag metal powders, underscoring their ability to enhance the curing rate of epoxy resin systems involving diacids and anhydrides but not amines. This research points toward a promising trajectory for multifarious epoxy-related applications.
环氧树脂因其出色的粘附能力以及强大的机械和热性能，在各种应用中具有广泛的用途。然而，苛刻的反应条件，包括较长的反应时间和较高的反应温度要求，在使用环氧树脂时带来了重大挑战，特别是在寻求卓越材料性能的先进应用中。为了克服这些限制，传统方法是加入有机催化剂。在本研究范围内，我们探索了金属粉末，特别是铋（Bi）和银（Ag），在含有各种固化剂（如二酸、酸酐和胺）的环氧树脂中的催化潜力。金属粉末在环氧 - 二酸和环氧 - 酸酐体系中表现出有效的催化活性。相比之下，它们对环氧 - 胺体系的影响可忽略不计，这归因于缺乏必要的羧酸盐官能团。此外，Bi和Ag的催化性能不同，由于Bi粉末表面存在固有的金属氧化物层，其显示出更高的效率。值得注意的是，未催化的、完全固化的环氧树脂的热性能和机械性能与催化后的环氧树脂非常相似。这些发现突出了Bi和Ag金属催化剂的潜力，特别是在环氧 - 二酸和环氧 - 酸酐体系中，涵盖了一系列基于环氧树脂的应用。总之，本研究阐明了Bi和Ag金属粉末的催化能力，强调了它们提高涉及二酸和酸酐但不涉及胺的环氧树脂体系固化速率的能力。这项研究为各种与环氧树脂相关的应用指明了一条充满希望的道路。
