表面重构是高分子材料表面为响应温度和环境变化的自发行为，其具有时间和空间效应的重构模式对塑料的浮选行为产生了重要影响。本项目将借助近现代表面分析仪器与检测手段，对塑料浮选体系中的聚合物大分子表面重构、增塑剂小分子的迁移与表面重构、填充剂外露后表面重构三大类表面重构行为进行系统研究，从热力学和动力学两方面在分子（基团）层面上描绘出塑料表面在界面能最低原则驱动下的复杂而有序的重构情景。在此基础上，通过合理改变塑料浮选各阶段的相界面接触形式、外场（等离子体、微波、UV辐照）作用方式、环境温度、氧化体系、润湿剂吸附模式等外部环境，创造和利用稳态甚至亚稳态状况下的表面重构结果，调节和控制聚合物疏水链段、亲水链段、增塑剂分子非极性基团、极性基团的翻转、氧化或降解进程，逐步积累和放大塑料之间的可浮性差异，从而确立表面重构基础上的塑料浮选高效调控机制，为实现复杂体系废旧塑料的浮选分离创造条件。

Surface reconstruction in polymer surface is a spontaneous behavior in response to the changes of temperature and environment, which possesses significant effects on the flotation behavior of plastics with respect to time and space. In order to systematically ascertain surface reconstruction of polymer macromolecule, plasticizer molecule and migrated additives in plastics flotation, with the aid of modern equipment of surface analysis, the complex and regular reconstruction driven by minimal interface energy in plastic surface will be investigated at the molecular level from thermodynamics and kinetics. Furthermore, the effects of external environmental factors will be studied, including interface patterns in each stage of flotation, external fields (plasma, microwave and UV), ambient temperature, oxidation and wetting agents adsorption, on metastable and steady state of surface reconstruction. The expected difference in the floatability of different plastics will be obtained and enhanced by regulating and controlling the turnover, oxidation or degradation process of the hydrophilic and hydrophobic molecular chains of polymers, non-polar and polar molecule groups of plasticizer. Consequently, an efficient regulating mechanism concerning surface reconstruction and plastics flotation will be accomplished to facilitate separation of waste plastics in complex systems.