Inorganic Suspensions Using Well-Defined Copolymeric Stabilizers

本研究涉及低水平共聚物对水性胶体悬浮液性能影响的基础研究。系统地设计，新颖的嵌段和接枝共聚物，每个嵌段的分子量分布都很窄，并与具有窄尺寸分布的选定胶体颗粒混合。吸附共聚物对悬浮液稳定性和性能的影响将通过流变性和光散射等技术来测量。为了研究颗粒浓度对悬浮液微观结构的临界影响，将颗粒浓度范围从稀释到高浓度。空间稳定性是由共聚物上的水溶性尾部段提供的，该共聚物通过吸附的疏水头块锚定在颗粒上。水不溶性块作为锚的有效性将作为化学结构的函数来研究。预计粒子表面和吸附共聚物之间的特定相互作用将在水性氢键介质中特别重要。除了空间稳定机制外，静电稳定对带电尾段的情况也很重要。待研究的颗粒将是表征良好的无机材料，主要是SiO2、Al2O3、SiC和Si3N4。

This research concerns a fundamental study of the effect of low levels of copolymers on the properties of aqueous colloidal suspensions. Systematically designed, novel, block and graft copolymers with narrow molecular-weight distributions of each block will be synthesized and mixed with selected colloidal particles having narrow-size distributions. The effect of the adsorbed copolymers on the stability and properties of the suspensions will be measured by techniques including rheology and light scattering. The particle concentrations will range from dilute to highly concentrated in order to study the critical effect of particle concentration on suspension microstructure. Steric stability is provided by a water-soluble tail segment on the copolymer that is anchored to the particle by an adsorbed hydrophobic head block. The effectiveness of the water-insoluble block as an anchor will be studied as a function of chemical structure. It is anticipated that specific interactions between the particle surface and the adsorbed copolymer will be of particular importance in aqueous, hydrogen-bonding media. In addition to the steric stabilization mechanism, electrostatic stabilization is also important for the case of charged tail segments. The particles to be studied will be well-characterized inorganic materials, primarily SiO2, Al2O3, SiC, and Si3N4.