Swelling-controlled solute diffusion in glassy polymers

玻璃态聚合物中的渗透传递在传统的工程应用中起着重要作用，如膜、包装和阻隔材料。最近，这种现象在从微米和纳米纤维到用于药物递送的溶胀控制水凝胶的设计的应用中变得越来越重要。在后一种情况下，大量体积溶胀和截留溶质的扩散的存在可能进一步使总速率过程复杂化。这种膨胀和扩散通常不遵循菲克扩散机制。虽然在玻璃状聚合物中的单一渗透剂运输的情况下已被广泛研究，在聚合物中的初始溶质浓度水平对溶剂渗透特性的影响尚未得到适当的研究，和溶胀过程中所观察到的溶质从玻璃状聚合物，特别是水凝胶的释放行为的作用，尚未最终解决。

Penetrant transport in glassy polymers has played a major role in traditional engineering applications such as membranes, packaging and barrier materials. More recently, this phenomenon has become increasingly important in applications ranging from micro and nanofabrication to the design of swelling-controlled hydrogels for drug delivery. In the latter case, the presence of a substantial volume swelling and the diffusion of entrapped solute may further complicate the overall rate process. Such swelling and diffusion generally do not follow a Fickian diffusion mechanism. Although the case of a single penetrant transport in glassy polymers has been studied extensively, the effect of initial solute concentration level in the polymer on the solvent penetration characteristics has not been properly studied, and the role of the swelling process in relation to the observed solute release behaviour from glassy polymers, in particular hydrogels, has not been conclusively resolved.