Study on Stabilized of Poly(Vinyl Alcohol) Nanofibers Based Sandwich Structure Purification Material

Abstract

PVA nanofibers are generally required to be modified because of its poor stability in water. The water stability of PVA nanofibers was improved by heat treatment in this paper. The DSC test results showed that the crystallinity of heat-treated PVA nanofibers at 150°C for 10 min reached the maximum which increased by 12% compared with PVA nanofibers. From the SEM images it was observed that the heat-treated fibers didn’t dissolve in water but showed certain degree of agglutination and swelling. PVA nanofibers were taken as the inner layer of the sandwich structure purification material prepared with the hot pressing technology. The filtering experiments showed that the filtration properties were better when the area density of PVA nanofibers was 2.5 g/m2.

Physical stabilisation of electrospun poly(vinyl alcohol) nanofibres: comparative study on methanol and heat-based crosslinking

“…The hydroxyl groups of PVA can form hydrogen bonds which lead to the formation of small crystallites due to heat treatment, and these crystallite domains serve as crosslinks to hold the three-dimensional structure together [32]. Liu et al [25] and Wang et al [33] have stabilized PVA nanofibers with heat treatment. Wong reported that heat treatment increased the crystallinity of PVA nanofibers and the stability of fibres in water can be achieved by increasing the heat treatment temperature and/ or treatment time.…”

“…Crosslinking can be divided into two categories; chemical and physical [25]. Chemical crosslinking is carried out by chemical crosslinkers such as glutaraldehyde, bis-epoxide, diisocyanate, methacrylate, multifunctional agents that create permanent and irreversible covalent bonds between the chains of the polymers [8,25]. Physical crosslinking maybe carried out by freeze-thawing, cooling with subsequent stretching, heat treatment and methanol treatment.…”

“…Crosslinking forms a three-dimensional network by joining polymer chains with one another and therefore increases fibre stability as well as other physical properties. Crosslinking can be divided into two categories; chemical and physical [25]. Chemical crosslinking is carried out by chemical crosslinkers such as glutaraldehyde, bis-epoxide, diisocyanate, methacrylate, multifunctional agents that create permanent and irreversible covalent bonds between the chains of the polymers [8,25].…”

Effect of heat treatment on morphology and crystallinity of electrospun Poly(vinyl alcohol) nanofibers

“…To overcome that problem, the polymers should be crosslinked (chemically or physically) to form the three-dimensional structure, consequently improve the stability and physical properties of nanofibers PVA. [5].…”

“…Chemical crosslinking is conducted with chemical crosslinkers such as glutaraldehyde, methacrylate, diisocyanate, bis-epoxide, multifunctional chemicals that form a permanent and irreversible covalent bond between the polymer chains [5,6]. Physical crosslinking can be done by freeze-thawing, cooling with subsequent stretching, methanol treatment and heat treatment [7,8].…”