A new type of micro-osmometer is described in which water absorption of small tissue samples is measured by a quartz crystal microbalance (QCM). The swelling of the sample deposited on the surface of a quartz crystal is determined by monitoring the change in resonance frequency of the quartz sensor as a function of the vapor pressure in the surrounding environment. The measurement principle is ...

in this research, hydrogels based on poly vinyl alcohol and poly acrylic acid blend were prepared which were cross-linked by applied thermal conditions. afterward, effects of time and heating on water uptake were investigated. the highest water uptake value exhibited by the sample that was heated for 20 min. at 110 ºc was about 2129% after 4 days at equilibrium state. hydrogels exhibited ph-sen...

The kinetics of Ag nanoparticle photogeneration inside optically transparent thin polymer films was studied. Light sensitive polymer films able to initiate the reduction of Ag ions were prepared by blending poly(vinyl alcohol), PVA, and sulphonated poly(ether etherketone), SPEEK. Photolysis of such films with 350 nm photons produced benzophenyl ketyl (BPK) radicals of SPEEK, which are strong re...

Antifreeze (glyco) proteins are produced by many cold-acclimatized species to enable them to survive subzero temperatures. These proteins have multiple macroscopic effects on ice crystal growth which makes them appealing for low-temperature applications-from cellular cryopreservation to food storage. Poly(vinyl alcohol) has remarkable ice recrystallization inhibition activity, but its mode of a...

Block copolymers represent an exciting class of complex materials as they self-assemble into highly regular structures of nanoscopic dimensions. When prepared as thin films, such structures can be used for a variety of applications including lithographic masks or nanoporous membranes. Reported here are nanostructures in thin films of structurally analogous polybutadiene-block-poly(2-vinyl pyrid...

Environmental pollution and food safety are both issues of global concern. In this sense, sustainable antimicrobial nanocomposites based on cellulose/poly (vinyl alcohol) blend incorporated with natamycin cellulose nanocrystals (CNC) were manufactured characterized. The developed films evaluated according to their mechanical optical properties, barrier oxygen water vapor permeation. antimycotic...

Polyaniline (PANI) nanocomposite has been successfully prepared in aqueousmedia by the chemical polymerization of aniline with ammonium peroxydisulphateas an initiator in the presence of a steric stabilizer such as sodium dodecylbenzenesulfonate(DBSNa), Poly(vinyl pyrrolidone) (PVP), poly(vinyl alcohol)(PVA), poly(ethylene glycol) (PEG) and hydroxypropylcellulose (HPC). Thechemical structure, m...