The effect of humidity on the morphological and thermomechanical properties of electrospun poly(vinyl alcohol) (PVA) fiber mats reinforced with cellulose nanocrystals (CNs) was investigated. Scanning electron microscopy (SEM) images revealed that the incorporation of CNs improved the morphological stability of the composite fibers even in high humidity environments. Thermal and mechanical properties of the electrospun fiber mats were studied by using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and large deformation tensile tests under controlled humidity and temperatures. The balance between the moisture-induced plasticization and the reinforcing effect of rigid CN particles was critical in determining the thermomechanical behaviors of the electrospun fiber mats. Results indicated that the stabilizing effect of the CNs in the PVA matrix might be compromised by water absorption, disrupting the hydrogen bonding within the structure. The amount of this disruption depended on t...
Maria S. Peresin; Youssef Habibi; Arja-Helena Vesterinen; Orlando J. Rojas; Joel J. Pawlak; Jukka V. Seppälä
The successful applicability of gene therapy approaches will heavily rely on the development of efficient and safe nonviral gene delivery vectors, for example, cell-penetrating peptides (CPPs). CPPs can condense oligonucleotides and plasmid DNA (pDNA) into nanoparticles, thus allowing the t ... mehr
Dendrimers feature a defined number of terminal groups that may bind RNA or be functionalized with bioactive molecules. These competing uses of terminal groups may create an impasse if the requisite density of ligands depletes the number of terminal groups for binding sufficient RNA, or vic ... mehr
The development of clay bionanocomposites requires processing routes with nanostructural control. Moreover, moisture durability is a concern with water-soluble biopolymers. Here, oriented bionanocomposite coatings with strong in-plane orientation of clay platelets are for the first time pre ... mehr