单链交联纳米粒子的合成及流变学研究

Synthesis and Rheological Study of Single-Chain Cross-Linked Nanoparticles

单链交联纳米粒子(Single-chain cross-linked nanoparticles,简称SCNP)由分子内交联反应来制备而得,直径较小,结构类似于无序蛋白,这些独特的性质吸引了人们的广泛关注。SCNP的合成方法有很多,苯并环丁烯的环加成反应是较为成熟的一种,该反应原理简单,效率高,适合SCNP的高效合成。SCNP是一种典型的三维形状高分子,其动力学行为丰富多样,可以通过流变实验来进行研究。在这里,我们使用原子转移自由基聚合(Atom transfer radical polymerization,简称ATRP)的方法制备了4-乙烯基苯并环丁烯(4-vinylbenzocyclobutene,简称BCB)与苯乙烯共聚作为线形前驱体,并采用连续滴加法合成了SCNP。最后所得到的产物进行核磁共振谱(NMR)、凝胶渗透色谱(GPC)、动态光散射(DLS)、差示量热扫描(DSC)等表征。我们使用了商用流变仪对SCNP样品进行小幅振荡剪切(Small oscillating shear,简称SAOS)测试,通过对得出的SAOS曲线进行分析来研究其线性黏弹性行为。

Single-chain cross-linked nanoparticles(SCNP)are prepared by intramolecular cross-linking reactions.They have a small diameter and a structure similar to disordered proteins.These unique properties have attracted people's attention.extensive attention.There are many methods for the synthesis of SCNP.The cycloaddition reaction of benzocyclobutene is a relatively mature one.The reaction principle is simple and the efficiency is high,which is suitable for the efficient synthesis of SCNP.SCNP is a typical three-dimensional shape polymer with rich and diverse dynamic behavior that can be studied by rheological experiments.Here,we prepared 4-vinylbenzocyclobutene(BCB)with styrene as a linear precursor by Atom transfer radical polymerization(ATRP),and synthesized SCNP by continuous drop addition.The resulting products were characterized by nuclear magnetic resonance spectroscopy(NMR),gel permeation chromatography(GPC),dynamic light scattering(DLS),and differential calorimetry(DSC).We used a commercial rheometer to perform a small oscillating shear(SAOS)test on SCNP samples to study their linear viscoelastic behavior by analyzing the resulting SAOS curves.