PDF(Pubmed)
Abstract：
Soft materials bearing rigid, lightweight, and vibration-dampening properties offer distinct advantages over traditional wooden and metal-based fillings for spent fuel transport casks, due to their low density, tunable structure, excellent mechanical properties, and ease of processing. In this study, a novel type of rigid polyurethane foam is prepared using a conventional polycondensation reaction between isocyanate and hydroxy groups. Moreover, the density and size of the pores in these foams are precisely controlled through simultaneous gas generation. The as-prepared polyurethane exhibits high thermal stability exceeding 185 °C. Lifetime predictions based on thermal testing indicate that these polyurethane foams could last up to over 60 years, which is double the lifetime of conventional materials of about 30 years. Due to their occlusive structure, the mechanical properties of these polymeric materials meet the design standards for spent fuel transport casks, with maximum compression and tensile stresses of 6.89 and 1.37 MPa, respectively, at a testing temperature of -40 °C. In addition, these polymers exhibit effective flame retardancy; combustion ceased within 2 s after removal of the ignition source. All in all, this study provides a simple strategy for preparing rigid polymeric foams, presenting them as promising prospects for application in spent fuel transport casks.
摘要：
软材料支承刚性，轻量级，与传统的木质和金属基填料相比，用于乏燃料运输桶的减振性能具有明显的优势，由于它们的低密度，可调结构，优异的机械性能，和易于处理。在这项研究中,使用异氰酸酯和羟基之间的常规缩聚反应制备了一种新型的硬质聚氨酯泡沫。此外，这些泡沫中的孔的密度和尺寸通过同时产生气体来精确控制。所制备的聚氨酯表现出超过185°C的高热稳定性。基于热测试的寿命预测表明，这些聚氨酯泡沫可以持续超过60年，这是约30年的传统材料寿命的两倍。由于它们的闭塞结构，这些聚合物材料的机械性能符合乏燃料运输桶的设计标准，最大压缩和拉伸应力为6.89和1.37MPa，分别,在-40°C的测试温度下。此外,这些聚合物表现出有效的阻燃性;燃烧停止后2秒内除去点火源。总而言之，这项研究为制备硬质聚合物泡沫提供了一种简单的策略，将它们作为在乏燃料运输桶中应用的有希望的前景。
