微胶囊化新型聚硫橡胶密封剂的性能试验与评估

目的研发新型聚硫橡胶密封剂,并对其性能进行综合评估。方法基于原位聚合技术,制备以脲醛树脂为壁材,液态聚硫橡胶为囊芯的微胶囊。通过考察微胶囊密封剂的稳定可靠性、力学性能(力矩和拉伸性能)等,系统评价新型微胶囊密封剂的综合性能。结果通过聚硫密封剂微胶囊化,可将其装配工序由5步简化成1步,实现密封剂的预涂覆功能。微胶囊密封剂的稳定可靠性实验结果表明,长期储存后,微胶囊颗粒形貌不变,芯材聚硫橡胶未泄露和变性,保持良好的化学反应活性。力学性能试验结果表明,与原密封剂相比,微胶囊密封剂的破坏力矩、拆卸力矩、拉伸强度和断裂拉伸强度明显提高,断裂伸长率有所下降。结论通过脲醛原位聚合技术成功制备出形貌规整、粒径分布单一的聚硫密封剂微胶囊,实现聚硫密封剂包得住、不变性的目的。囊壁材料的引入对于密封剂力学性能有较大影响。

Performance Test and Assessment of New Microencapsulated Polysulfide Rubber Sealant

The paper aims to design and evaluate a novel microcapsule of polysulfide rubber sealant. Microcapsules were designed and prepared by in situ polymerization technology with the poly (urea-formaldehyde) resin (PUF) as shell material and the polysulfide rubber as core material. By investigating the stability reliability and the mechanical properties (torque and tensile property) of the microcapsule sealant, the comprehensive properties of microcapsule sealant were evaluated systematically. The function of pre-coating of polysulfide sealant was realized by microencapsulation technology. In this way, the assembly procedures of polysulfide sealants can be simplified from five steps into one step. The experimental results of the stability and reliability of microcapsule sealant showed that the microcapsule particles maintained the structure and morphology during long term storage. The core materials were free from leakage and degeneration and were kept of good chemical reactivity. Experimental results of the mechanical properties further demonstrated that although the fracture elongation rates slightly decreased, the breakaway and disassembly torques as well as tensile strength (at break) of cured polysulfide films were greatly improved, compared with the original sealant. The polysulfide sealant microcapsules with regular morphology and single size distribution were successfully prepared by in situ polymerization of urea-formaldehyde, achieving the purpose of microencapsulation and immutability of liquid polysulfide. The introduction of the capsule wall material has great influences to the mechanical properties of sealant.