Shape memory polyurethane foams
Shape memory polyurethane foams
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DOI：
10.3144/expresspolymlett.2012.7
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发表时间：
2012-01-01
影响因子：
3.3
通讯作者：
Kim, B. K.
中科院分区：
文献类型：
--
作者：
Kang, S. M.;Lee, S. J.;Kim, B. K.
以不同分子量（M-w）和官能度（f）的聚丙二醇（PPG）和2，4/2，6-甲苯二异氰酸酯（TDI-80）为原料，以水为发泡剂，合成了模塑软质聚氨酯（PU）泡沫塑料。结果表明，泡沫的玻璃态性能主要取决于聚氨酯基团的含量，而橡胶态性能则取决于交联密度。也就是说，低MW和低f（更多氨基甲酸酯基团）的PPG提供上级的玻璃态模量、强度、密度、形状固定性和玻璃化转变温度（T-g），而高M-w和高f（较高交联密度）的PPG显示高橡胶态模量和形状恢复。因此，随着高M-w PPG的含量从0增加到40%，低M-w PPG的形状固定性从85%降低到72%，而形状恢复从52%增加到63%。
Molded flexible polyurethane (PU) foams have been synthesized from polypropylene glycol (PPG) with different molecular weights (M-w) and functionalities (f), and 2,4/2,6-toluene diisocyanate (TDI-80) with water as blowing agent. It was found that the glassy state properties of the foam mainly depended on the urethane group content while the rubbery state properties on the crosslink density. That is, PPG of low MW and low f (more urethane groups) provided superior glass state modulus, strength, density, shape fixity and glass transition temperature (T-g), while that of high M-w and high f (higher crosslink density) showed high rubbery modulus and shape recovery. Consequently shape fixity of low M-w PPG decreased from 85 to 72% while shape recovery increased from 52 to 63% as the content of high M-w PPG increased from 0 to 40%.