Synthesis and Characterization of Functionalized Polyethylene Surfaces

9634196 Bergbreiter这笔赠款将探索聚烯烃表面改性的几个新方面。拟议项目的初始阶段将扩展先前对“响应性”表面的研究--即响应外部物理或化学刺激而可逆地改变亲水性、粘附性和/或反应性的表面。通过结合几种不同类型的光谱探针并通过化学调整聚合物接枝的结构，将有可能测试如何在聚合物表面化学控制和操纵溶剂化和反应性。这种化学反应将通过线状刷状移植物来探索。其次，将研究一种利用超支化聚合物进行表面接枝的新方法。初步工作已经表明，超支化接枝化学可以在表面生成高度官能化的聚合物接枝薄膜(10-150 nm)。这种化学也可以用来产生响应性表面，通过设计，可以在接枝相、接枝/溶剂界面或接枝相/底物界面结合光谱标记。最后，已知的用于聚丙烯聚合的茂金属催化剂使末端官能化的立体正规聚丙烯齐聚物容易获得。这种低聚物可以用以前用于制备末端官能化的聚乙烯低聚物的化学方法进行合成修饰和表征。然后，这些末端官能化的低聚物将通过共混方法用于制备表面官能化的聚丙烯薄膜，这种方法的用途已被确定为使用聚乙烯低聚物和聚乙烯主体聚合物。%这笔赠款是在聚合物合成领域，用于表面的设计和修改。这种聚丙烯官能化的新方法可以与本建议和以前的工作中开发的新型化学接枝化学S一起使用。这一结果将为高效的聚丙烯表面改性开辟一条新的途径。***

9634196 Bergbreiter This grant will explore several new aspects of polyolefin surface modification. The initial stages of the proposed project will extend prior studies on "responsive" surfaces - surfaces that reversibly change hydrophilicity, adhesion and/or reactivity in response to external physical or chemical stimuli. By incorporating several different sorts of spectroscopic probes and by chemically tuning the structure of polymer grafts, it will be possible to test how to chemically control and manipulate solvation and reactivity at polymer surfaces. This chemistry will be explored with linear brush-like grafts. Second, a new approach to surface grafting using hyperbranched polymers will be studied. Preliminary work has already shown that hyperbranched grafting chemistry can generate heavily functionalized thin (10 - 150 nm) films of polymer grafts at surfaces. This chemistry can also be used to generate responsive surfaces and can, by design, incorporate spectroscopic labels either in the graft phase, at the graft/solvent interface or at the graft phase/substrate interface. Finally, known metallocene catalysts used in polypropylene polymerization make terminally functionalized stereoregular polypropylene oligomers readily available. Such oligomers can be synthetically modified and characterized using chemistry previously used to prepare terminally functionalized polyethylene oligomers. These terminally functionalized polypropylene oligomers will then be used to prepare surface functionalized polypropylene films by a blending approach whose utility has been established using polyethylene oligomers and a polyethylene host polymer. %%% This grant is in the area of polymer synthesis for design and modification of surfaces. This new approach to polypropylene functionalization can be used with the new sort s of chemical grafting chemistry to be developed in this proposal and in prior work. The result will be a new way to efficiently surface modify polypropylene. ***