Characterization of konjac glucomannan–quaternized poly(4‐vinyl‐N‐butyl) pyridine blend films and their preservation effect

Abstract

Novel polymer blends were prepared from a mixture of 2 wt % konjac glucomannan and 4 wt % quaternized poly(4-vinyl-N-butyl) pyridine (QPVP) in aqueous solution and dried at room temperature for 72 h. Their structure and properties were studied by infrared, wide-angle X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, and differential scanning calorimetry. Thermal stability in the dry state was reduced with increasing content of QPVP. Compared with QPVP film, the tensile strength of the films was improved in the dry state. The maximum value of 12.74% tensile break elongation was reached when the content of QPVP was 30%. Structural analysis indicated that clear phase separation was observed when the content of QPVP was only 50%. Results from the filmcoating preservation experiments with lychee showed that this blend film had water-holding ability. The fruit weight loss rate and rot rate both decreased in various degrees. The potential uses of these novel polymer films could be as preservative films.

Carboxymethylcellulose acetate butyrate/poly(4-vinyl-N-pentyl pyridinium bromide) blends as antimicrobial coatings

“…It implies that the thermal stability of QPVP-C5 is enhanced due to the introduction of the CMCAB. A similar behavior was observed for blends of QPVP-C4/ konjac glucomannan, where the polysaccharide enhanced the blends thermostability [30].…”

“…Considering that strong acid-base interactions can cause shifts of up to 30 cm -1 in the carbonyl and carboxylic acid bands [29], the spectra in Figure 3 indicate the absence of such interactions. Liu and Xiao characterized blends of konjac glucomannan gum [30] or chitosan [31] with QPVP-C4 by means of FTIR and other analytical techniques, which evidenced intermolecular interactions between the polymers in the both blends. Whereas in the first case the stretching vibration of -OH in comparison to the pure konjac glucomannan gum shifted gradually to higher wavenumbers as the amount of QPVP-C4 increased, in the latter the -NH 2 band of chitosan split in two denoting interaction with QPVP-C4.…”

Effects of crosslinking density on structure and properties of interpenetrating polymer networks from polyurethane and nitroguar gum

“…Guar gum (GG) was kindly supplied by Wuhan Tianyuan Biology Industries, China. The method of preparation and purification were followed as described earlier [19]. The castor oil was chemically degraded and was dried at 1108C under 20 mm Hg for 2 h. Commercial 2,4-toluene diisocyanate (TDI; Shanghai Chemical, China) was vacuum-dried at 808C for 2 h and was used as hard segments.…”

A novel adsorbent obtained by caging activated carbon by konjac glucomannan gel for elimination of organic compounds

“…The gelation structure of KGM (see Figure ) was provided by Alonso‐Sande et al The molecular weight of KGM is ∼10 6 and it has many advantages such as, nontoxic, low cost, having excellent film‐forming ability, good biocompatibility, biodegradability, and a high viscosity . Because of these physical and chemical characteristics, KGM has been widely used in packing and preservatives material, controlling released material, wood adhesives, enzyme entrapment, and drug carrier . KGM gel (KGMG) is formed by heating a KGM solution in the presence of alkali compound or higher amount of neutral salt .…”