聚N-异丙基丙烯酰胺链构象转变以及溶剂化效应的分子动力学模拟

摘要

Molecular dynamics simulations have been adopted to study the conformation state of PNiPA (n=100)in gas phase and aqueous solution.The chains collapse into a compacted glob-ule at 500K gradually.The end-to-end distance decreases,which is in agreement with experi-mental phenomena.Further investigations indicate that de-solvation process occurs on both (C) O and (N)H groups of NiPA with the increase of temperature,and polymer segments begin to aggregate together.%应用分子动力学方法模拟了聚合度为100的聚N-异丙基丙烯酰胺分子链在真空和稀水溶液中的构象转变。可以观察到分子链在500 K下逐渐发生蜷缩，末端距下降，与实验现象定性一致。此外，研究结果还表明，随着温度的升高，高分子链重复结构单元 NiPA上(C)O 和(N)H 基团均发生明显的去溶剂化作用，且高分子链段间发生聚集。