Tailored non-ionic polymers with UCST-type phase transition properties in water and electrolytes

该项目涉及定制的非离子聚合物的合成，显示在水和电解质中的上临界溶解温度（UCST）型相变，以及使用散射方法在不同长度和时间尺度上的相变行为的研究。术语水溶性温敏聚合物目前是表现出较低临界溶解温度（LCST）的聚合物的同义词。在水和电解质水溶液中表现出上临界溶解温度（UCST）的非离子聚合物是罕见的，具有非常有限的实例。本提案的主题是这一尚未开放、创新、有希望但研究不够的领域。我们建议，使适当的非离子聚合物能够进行热可逆氢键导致UCST型相变的基础上的均聚物和共聚物的（甲基）丙烯酰胺和α-取代的衍生物（（烷基）丙烯酰胺）。这些定制的聚合物将提供一系列具有玻璃化转变温度（链流动性）和亲水/疏水比的系统变化的样品，用于研究作为聚合物和电解质浓度、加热/冷却速率、链流动性、摩尔质量和聚合物微结构的函数的相变行为，通过光散射（全局长度尺度）以及SANS（局部形态）。

The project deals with the synthesis of tailor made non-ionic polymers showing upper critical solution temperature (UCST)-type phase transitions in water and electrolytes and the investigation of the phase transition behavior on different length and time scales using scattering methods. The term water-soluble thermoresponsive polymer is at present a synonym for polymers showing lower critical solution temperature (LCST). The non-ionic polymers which exhibit upper critical solution temperature (UCST) in water and aqueous electrolyte solutions are rare with very limited examples. This yet open, innovative, promising and not very well studied area is the topic of the present proposal. We propose to make appropriate non-ionic polymers capable of undergoing thermally reversible hydrogen bonding leading to UCST-type phase transitions based on homo- and co-polymers of (meth)acrylamide and alpha-substituted derivatives ((alkyl)acrylamides). These tailor made polymers would provide a series of samples with systematic variation in glass transition temperature (chain mobility) and hydrophilic/hydrophobic ratio for studying the phase-transition behavior as a function of polymer and electrolyte concentration, heating/cooling rates, chain mobility, molar mass and polymer microstructure by light scattering (global length scales) as well as SANS (local morphologies).