相分离、去润湿和结晶耦合作用对聚合物共混薄膜形态结构演变行为的影响

Tuning the morphology of the polymer blends film is an effective method to obtain film materials with desirable properties, which makes it an extremely valuable research focus of polymer physics. With the combination of our previous fundamental research in the micro-phase separation and dewetting of block copolymer film, we propose the research in the phase separation, crystallization and dewetting phase transition of crystalline/noncrystalline blending polymer film as follows: 1) exploring the influence of external fields for the phase separation and crystalline morphological structure of blending films, in order to perfect the mechanism of the formation of various morphological structures which undergoes interaction and competition between phase separation and crystallization phase transition in the process of film preparation; 2) Study and discuss the effect of crystalline components on the dewetting mechanism and kinetics of polymer blend films, and analyzing the physical nature which renders the anisotropic dewetting behavior with reference to theoretical dynamics and kinetics; 3) Investigate the influence of the synergistic effect between noncrytalline components and substrate on the orientation of crystal lamella, and deeply recognizing the condition of the crystallization behavior and the lamellar orientation control of crystalline polymer film from the perspective of polymer physics. Based on the above research, a relation between the interaction or competition of phase separation, crystallization and dewetting and the evolution of the film surface component structures can be established, which in turn provides theoretical guidance and approaches for the fabrication of polymer blends film materials and devices with multi-scale structures.

调控聚合物共混薄膜的结构是获得具有预想性能薄膜材料的有效途径，也是高分子物理学中的热点问题，具有重要的研究价值。本项目结合我们在嵌段共聚物薄膜微相分离和去润湿方面的研究基础，针对结晶/非晶共混聚合物薄膜中相分离、结晶和去润湿的相转变行为拟进行如下研究：(1) 研究外场条件对共混薄膜的相分离及结晶形态结构的影响。完善聚合物薄膜成膜过程中相分离与结晶相转变相互影响与竞争条件下各形态结构的形成机理。（2）探讨结晶组分对聚合物共混薄膜的去润湿机理和动力学的影响，从理论上从热力学和动力学角度分析致使各向异性去润湿行为的物理本质。(3)探讨非晶组分和基底的协同作用对聚合物片晶取向的影响，揭示受限条件下高分子晶体生长与和片晶取向规律与机理。通过以上研究，构建相分离、结晶和去润湿之间的相互影响竞争与薄膜表面组成结构演变之间的关系，为利用聚合物共混薄膜制备多尺度结构的材料和器件提供理论指导与新的思路。

调控聚合物共混薄膜的组成和聚集态结构是获得具有预想性能薄膜材料的有效途径，也是高分子物理学中的热点问题，具有重要的研究价值。本项目针对非晶/结晶(PS/PCL)共混聚合物薄膜体系，系统研究了成膜和退火过程中相分离、结晶和去润湿多重相转变条件下共混薄膜形态结构的形成和演变机理。（1）通过控制聚合物薄膜的组成和膜厚研究了旋涂过程中相分离、去浸润及结晶的相互影响及其产生的各种形态结构。对旋转涂膜过程中所发生的物理过程提出一种垂直相分离，相界面的不稳定导致液-液去润湿形态形成的机理。完善了聚合物薄膜成膜过程中相分离与结晶相转变相互影响与竞争条件下各形态结构的形成机理。（2）研究了共混组成对共混薄膜相分离和去润湿形态结构特征尺寸的影响。改变共混组成，共混薄膜表面形成了不同尺寸的PS海岛点缀不同PCL类球晶、单层平躺片晶和平躺树枝状晶体的复杂结构形态。进一步验证了垂直相分离然后液-液去润湿的形态演变机理。(3) 研究了在非晶组分中引入结晶组分，结晶组分扩散控制结晶形成了树枝状的晶体使得薄膜平面内组成具有各向异性，导致退火过程中膜的稳定性具有各向异性。提出了一种各向异性去润湿的薄膜破坏机理解释了这种新的发现，丰富和完善了对聚合物薄膜去润湿形态演变规律和机理的认识。(4)研究非晶组分PS的分子量和含量对PCL薄膜的结晶形态和片晶取向的影响与调控；通过调控LPS/PCL的组成、薄膜厚和结晶温度，LPS/PCL共混薄膜中的PCL可以在云母基底上附生结晶自组装形成了互相成60。或120。排列的纤维状结晶形态。通过此研究，揭示了受限条件下高分子晶体生长的机理和片晶取向规律，丰富了调控片晶取向的手段。