Novel Thermally Switchable Smart Polymer Films

这项拨款为一种新型接枝mitoarm三元聚合物系统的综合研究提供了资金，该系统在其表面组成中显示出热响应变化。将开发合成路线，以生产具有不同块臂长度接枝到刚性和柔性基板上的mitoarm三元聚合物。这些接枝三元共聚物薄膜的热行为将使用先进的实验技术和计算模型进行评估。这些接枝的三聚体的行为将被研究最初使用块，这将导致在亲水性或疏水性表面之间的可逆切换。预计三元共聚物的复杂相行为是由热力学和动力学控制的，因此这些接枝三元共聚物体系的相行为将被研究，相图将被建立为相对臂分子量的函数。链动力学对平衡和非平衡相行为的影响将被研究，从而可预测地调整表面能的能力，从而严格评估表面润湿。研究了热梯度和局部退火对控制三元共聚物表面横向润湿行为的影响。该项目二期将研究温度循环过程中三元共聚物相对臂长不对称对表面曲率和曲率反转的影响。该项目的成功可能会对许多技术应用产生非常广泛的影响，这些技术应用对表面行为的控制很重要，包括表面润湿和粘附，以及乳液或囊泡等相转化系统。预测发生在不对称三元聚合物体系中的表面曲率反转将具有定义的随时间变化的动态反转行为，该行为由温度控制。这可能对智能表面应用（如药物输送平台）产生重要影响，可能开辟智能表面行为的新前沿。

This grant provides funding for a comprehensive study of a novel type of grafted miktoarm terpolymer system, which displays thermally responsive changes in their surface composition. Synthetic routes will be developed to produce miktoarm terpolymers with varying block arm lengths grafted onto both rigid and flexible substrates. The thermal behavior of these grafted terpolymer films will be evaluated using advanced experimental techniques and computational modeling. The behavior of these grafted terpolymers will be studied initially using blocks which would lead to reversible switching between hydrophilic or hydrophobic surfaces. The complex phase behaviour of the terpolymer is predicted to be both thermodynamically and kinetically controlled, consequently the phase behavior of these grafted terpolymer systems will be investigated and phase diagrams established as a function of relative arm molecular weights. The influence of chain dynamics on the equilibrium and non-equilibrium phase behavior will be investigated and hence the ability to predictably tune surface energies and therefore surface wetting critically evaluated. The effects of thermal gradients as well as localized annealing to control lateral wetting behavior of the terpolymer surface will be investigated. The effect of asymmetry of the relative arm lengths of the terpolymer on surface curvature and curvature inversion during temperature cycling will be studied in the second phase of the project.Success within the project could have very wide implications in numerous technological applications where control of surface behaviour is important, including surface wetting and adhesion as well as phase inversion systems such as emulsions or vesicles. Surface curvature inversion that is predicted to occur for asymmetric terpolymers systems would have a defined time-dependent dynamic inversion behaviour which is controlled by the temperature. This could have important implications for smart surface applications such as drug delivery platforms, which could open up a new frontier of smart surface behavior.