Abstract:

The mechanical properties and molecular structure of sprayed polyurea coating (QF-162 coating) and sprayed polyurethane coating (QF-178 coating) were studied by outdoor natural exposure in marine atmosphere. The results showed that the color change of QF-162 coating after outdoor exposure for 2 493 d was obvious, the tensile strength decreased by 29.37% and the elongation at break decreased by 14.38%. The color change of QF-178 coating was very significant. The tensile strength decreased by 90.71% and the elongation at break decreased by 98.75%. The results of FT-IR test showed that only the chemical bond of coating molecules on the coating surface was broken after natural exposure of QF-162 coating and the internal structure of the coating did not change much. However QF-178 coating after outdoor exposure for 2 493 d, the internal structure of molecular was changed significantly. Almost all the chemical bonds of molecules were broken and the use value of the coating was completely lost.

Key words: outdoor natural exposure, sprayed polyurea, sprayed polyurethane, coatings, mechanical property, protective property

摘要：

采用海洋大气环境户外自然曝晒的方法,研究了喷涂聚脲涂层(QF-162涂层)和喷涂聚氨酯涂层(QF-178涂层)的力学性能、分子内部结构的变化。结果表明:经过自然曝晒2 493 d后,QF-162涂层颜色变化明显,失光率为86.84%,拉伸强度下降29.37%,断裂伸长率下降14.38%; QF-178涂层颜色变化十分显著,失光率达89.63%,拉伸强度下降90.71%,断裂伸长率下降98.75%。FT-IR微观测试结果表明:在经过2 493 d的户外自然曝晒后,QF-162涂层只有涂层表面分子的化学键出现了断键,分子内部结构变化不大;而QF-178涂层分子内部结构发生显著的变化,分子的化学键几乎全部断裂,涂层完全失去了使用价值。

关键词: 户外自然曝晒, 喷涂聚脲, 喷涂聚氨酯, 涂层, 力学性能, 防护性能

CLC Number: 

• TQ630.7