摘要
传统环氧树脂存在的容易燃烧、高度依赖石油基原料等问题,无法满足木材涂料防火和低碳可持续发展的要求。笔者通过合成含有端仲胺基的香草醛基阻燃固化剂(HVPA),部分替代商品化胺类固化剂4,4′-二氨基二苯甲烷(DDM),用于固化生物基环氧树脂甘油二缩水甘油醚,制备了一种阻燃生物基环氧木材涂料。探究了HVPA的添加量对环氧树脂机械性能等基础性能的影响;将HVPA与DDM按不同质量比(0∶1,1∶3,1∶1,3∶1,1∶0)制备混合固化剂固化环氧树脂,并分别标记为EP-0、EP-25、EP-50、EP-75和EP-100。将EP-0~EP-100作为木材涂料涂敷于木材上进行锥形量热测试,探究HVPA对环氧木材性能的影响,并利用扫描电镜(SEM)及能谱仪(EDS)进行残炭分析,研究HVPA对木材涂料阻燃性能的阻燃机理。结果表明,HVPA作为固化剂不仅能提高环氧树脂的韧性,与EP-0相比提升了约942.9%,还能有效增强环氧木材涂料的阻燃性能,与EP-0相比,热释放速率分别降低了51.0%与62.9%,总热释放显著降低了52.3%。综上所述,本研究为环氧树脂在阻燃木材涂料领域的应用提供了新思路。
Traditional epoxy resins are easy to burn and highly dependent on petroleum-based raw materials, which cannot meet the requirements of fire prevention and low-carbon sustainable development of wood coatings. In this study, a kind of flame retardant bio-based epoxy resin wood coating was prepared by synthesizing vanilla aldehyde curing agent(HVPA) containing terminal secondary amine groups to partially replace commercial amine curing agent 4,4′-diaminodiphenyl methane(DDM) for curing the bio-based epoxy resin diglycidyl ether(GDE). The effect of the HVPA content on the mechanical properties and other basic properties of the epoxy resin was studied. The HVPA and DDM were mixed in different mass fractions(0∶1, 1∶3, 1∶1, 3∶1, 1∶0) to prepare mixed curing agents for the curing of epoxy resins, which were respectively labeled as EP-0, EP-25, EP-50, EP-75 and EP-100. EP-0~EP-100 were used as wood coatings for the cone calorimeter test and the char residue analysis was performed by the scanning electron microscope(SEM) and the energy dispersive spectrometer(EDS). The effect of HVPA on the flame retardancy of epoxy wood coatings and its flame retardancy mechanism was studied. The results showed that the utilization of HVPA as a bio-based curing agent for curing the GDE epoxy resin can improve the toughness and Tgof the epoxy resin. With the increase of HVPA addition, the toughness and Tggradually improved, and the tensile strength and elongation at break of EP-50 cured by HVPA and DDM at a mass ratio of 1∶1 were 67.6 MPa and 13.1%, respectively. The toughness reached the maximum of 7.3 MPa, the contact angle was the largest and the hydrophobicity was the strongest. The prepared wood coatings also had excellent coating properties. The results of the cone calorimetry test showed that the coating containing HVPA could effectively reduce the heat release and smoke release during combustion, and the comprehensive flame-retardant property of EP-50 was the best. The mechanism can be attributed to the fact that HVPA contains a large amount of nitrogen and phosphorus flame-retardant elements, and the phosphorus released by the thermal decomposition can form phosphoric acid to promote carbon formation. The phosphorus released by the thermal decomposition can form phosphoric acid to promote carbon formation and prevent further heat transfer to the wood substrate. The generation of non-combustible gases containing nitrogen can dilute combustible gases to inhibit combustion, improving the flame-retardant performance of epoxy wood coatings through the synergistic effect of the condensed phase flame retardant and the gas phase flame retardant. In conclusion, this study provides a new idea for the application of epoxy resin in the field of flame-retardant wood coatings.
作者
彭晶颖
刘涛
李堃伟
赵巾英
周旭
刘珍珍
王清文
PENG Jingying;LIU Tao;LI Kunwei;ZHAO Jinying;ZHOU Xu;LIU Zhenzhen;WANG Qingwen(Institute of Biomass Engineering,Key Laboratory of Energy Plants Resource and Utilization,Ministry of Agriculture and Rural Affairs,South China Agricultural University,Guangzhou 510642,China;College of Materials and Energy,South China Agricultural University,Guangzhou 510642,China;College of Food Science,South China Agricultural University,Guangzhou 510642,China)
出处
《林业工程学报》
CSCD
北大核心
2023年第1期112-118,共7页
Journal of Forestry Engineering
基金
广东省重点领域研发计划(2020B0202010008)
国家自然科学基金(32001264)。
关键词
香草醛
胺类固化剂
环氧树脂
阻燃
木材涂层
vanillin
amine curing agent
epoxy resin
flame retardancy
wood coating
