A new generation of hollow polymeric microfibers produced by gas dissolution foaming

Abstract

A new and straightforward route to produce polymeric hollow microfibers is proposed. Polycaprolactone (PCL) hollow fibers are obtained for the first time by an environmentally friendly gas dissolution foaming approach,...

Microfluidic Seeding of Cells on the Inner Surface of Alginate Hollow Microfibers

“…[2,3] In recent years, the fabrication of hydrogel-based microfibers that could mimic microvasculature systems has attracted many researchers in this area, and extensive research has been done to fabricate microfibers and to address cell encapsulation in these fibers. [4,5,[7][8][9][10][11] To improve the rheological and biological properties of microfibers, different organic and synthetic materials have been used for the fabrication of hydrogels and scaffolds; however, organic materials such as alginate-based microfibers showed better biocompatibility. [4][5][6][12][13][14] Different methods have been exploited to fabricate microfibers.…”

Production of Cellular Polymers Without Solid Outer Skins by Gas Dissolution Foaming: A Long-Sought Step Towards New Applications

“…Then, thicker samples may not form the cellular structure in the core due to the insufficient gas concentration by the quick diffusion (i.e., the polyamide layer does not act as a gas diffusion barrier). However, an approach involving a gas diffusion barrier, capable of limiting the diffusivity during the foaming process, allowed producing hollow micrometric and nanometric polymeric systems with porous surfaces by coating them with poly-vinyl alcohol (PVOH) prior to the gas dissolution foaming process [35,42].…”

“…Although several methods which concern multiple stages based on the gas dissolution foaming have been developed [35,37,[42][43][44], none of these previous approaches has proved to be a general and versatile approach to hinder the formation of the non-foamed skin during the gas dissolution foaming process, being limited in terms of geometry or expansion, or introducing complex additional steps without providing remarkable results.…”

Encapsulation of Copper Nanoparticles in Electrospun Nanofibers for Sustainable Removal of Pesticides

“…38,42 Among other polymers, polycaprolactone (PCL) presents excellent electrospinnable properties, being also a biodegradable, biocompatible, and water-resistant polymer which is extensively used for long-term drug-delivery systems. 2,43 For instance, Chen et al 35 obtained polymeric membranes with excellent antibacterial properties by combining PCL composite with copper oxide nanoparticles using electrospinning. In the field of water treatment, electrospun fibers of PCL have been proven to remove heavy metals and to separate oil stable emulsions when inorganic compounds such as kaolin clay 44 or silica nanoparticles, 45 respectively, are embedded in the matrix.…”

“…A novel strategy to retard the oxidation and to obtain a sustained response over time is the use of polymers as capping agents. − In the cases found in the literature, the polymer matrices include multiple reagents or several fabrication steps. ,, On the contrary, electrospinning is a modern technique that allows the fabrication of highly active metal/polymer composite mats in a single step. ,, Over the years, this technique has gained popularity due to its simple and versatile process, which consists of the production of fibers by applying a high-voltage electric field to a polymer solution injected from a syringe. , In the literature, these fibers have encapsulated active molecules such as antioxidants and metallic nanoparticles, providing tailoring properties, which can be applied in multiple fields, like food packaging, wound dressing, drug delivery, etc. , The high potential of electrospun fibers for pollutant removal application is linked to the large specific surface area, which is highly convenient to enhance the interaction with the target compound. , Among other polymers, polycaprolactone (PCL) presents excellent electrospinnable properties, being also a biodegradable, biocompatible, and water-resistant polymer which is extensively used for long-term drug-delivery systems. , For instance, Chen et al obtained polymeric membranes with excellent antibacterial properties by combining PCL composite with copper oxide nanoparticles using electrospinning. In the field of water treatment, electrospun fibers of PCL have been proven to remove heavy metals and to separate oil stable emulsions when inorganic compounds such as kaolin clay or silica nanoparticles, respectively, are embedded in the matrix.…”