Phase-Separating Polymer Blend Films Containing Nanoparticles

拟议的研究将集中在聚合物共混膜和含有纳米颗粒的聚合物共混膜的动力学。由于同时发生相分离和润湿，薄膜性能的控制，如硬度和渗透性，变得非常复杂。利用横向和深度剖析技术，将研究具有临界组成的共混物的相演变和润湿行为，其薄膜厚度为10 nm，约为旋转半径。通过控制微区尺寸和间距，可以制备出具有单分散、亚微米级微孔的膜。研究超临界共混物的相态和润湿动力学，以获得对膜稳定性、相间界面面积和润湿结构的控制。新的进化路径有望更好地洞察受限空间中的相分离、润湿和毛细管波动。第二个项目将研究惰性填充物，特别是可移动纳米颗粒，如何改变聚合物共混膜中相分离的速度和形态。在评估了二氧化硅纳米粒子的扩散和润湿之后，将使用先前研究开发的实验技术以及纳米粒子在薄膜中的深度和侧向轮廓的新技术来评估粒子尺寸、浓度和润湿性对微区演化和形貌的影响。所提出的研究是重要的，因为包含多个组分的聚合物薄膜对于包括光刻、粘合剂和显示器在内的许多技术至关重要。尤其是含有填料的聚合物共混物的实验研究在理论和商业应用上都有很大的滞后。基础研究将被汽车涂料工业感兴趣的商业填充聚合物薄膜的研究所补充。推广方案将继续，包括关于聚合物的第二个有线电视节目、在公立和私立小学的演示以及高中教师培训以及对本科生的培训。

The proposed research will focus on the dynamics of polymer blend films and polymer blend films containing nanoparticles. Control of film properties, such as hardness and permeability, are greatly complicated by the simultaneous occurrence of phase separation and wetting. Using lateral and depth profiling techniques, the phase evolution and wetting behavior of blends with a critical composition will be investigated for films as thin as 10 nm, ca. radius of gyration. By controlling domain size and spacing, membranes with monodisperse, submicron pores will be prepared. The phase and wetting dynamics of off-critical blends will be studied to gain control over film stability, interfacial area between phases, and wetting structure. New evolutionary pathways are anticipated yielding better insight into phase separation, wetting and capillary fluctuations in confined spaces. The second project will investigate how inert fillers, in particular mobile nanoparticles, modify the rate and morphology of phase separation in polymer blend films. After evaluating silica nanoparticle diffusion and wetting, the effect of particle size, concentration and wettability on domain evolution and morphology will be evaluated using the experimental techniques developed for the previous study as well as new techniques for depth and lateral profiling of the nanoparticles within the film.The proposed research is important because thin polymer films containing multiple components are critical to many technologies including photolithography, adhesives, and displays. In particular, experimental studies of polymer blends containing filler greatly lag both theory and commercial applications. Fundamental studies will be complimented by studies of commercial filler-polymer films of interest to the automotive coatings industry. Outreach programs including a second cable TV show on polymers, demonstrations at public and private elementary schools as well as high school teacher training will continue as will training of undergraduate students.