Silica-Like Malleable Materials from Permanent Organic Networks
Silica-Like Malleable Materials from Permanent Organic Networks
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DOI：
10.1126/science.1212648
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发表时间：
2011-11-18
期刊：
影响因子：
56.9
通讯作者：
Leibler, Ludwik
中科院分区：
文献类型：
--
作者：
Montarnal, Damien;Capelot, Mathieu;Leibler, Ludwik
永久交联材料具有出色的机械性能和耐溶剂性，但一旦合成，它们就无法加工和重塑。非交联聚合物和具有可逆交联的聚合物是可加工的，但它们是可溶的。我们设计了环氧网络，可以通过交换反应重新排列它们的拓扑结构而不解聚，并表明它们是不溶性和可加工的。与粘度在玻璃化转变附近突然变化的有机化合物和聚合物不同，这些网络显示出类似于玻璃质二氧化硅的Arrhenius式逐渐粘度变化。像二氧化硅一样，这些材料可以通过局部加热进行锻造和焊接，从而制造复杂的物体，而无需使用模具。通过在环氧网络中可逆拓扑冻结制成的玻璃的概念可以容易地按比例放大以用于应用并推广到其他化学。
Permanently cross-linked materials have outstanding mechanical properties and solvent resistance, but they cannot be processed and reshaped once synthesized. Non-cross-linked polymers and those with reversible cross-links are processable, but they are soluble. We designed epoxy networks that can rearrange their topology by exchange reactions without depolymerization and showed that they are insoluble and processable. Unlike organic compounds and polymers whose viscosity varies abruptly near the glass transition, these networks show Arrhenius-like gradual viscosity variations like those of vitreous silica. Like silica, the materials can be wrought and welded to make complex objects by local heating without the use of molds. The concept of a glass made by reversible topology freezing in epoxy networks can be readily scaled up for applications and generalized to other chemistries.