Abbreviations
AA Acrylic acid
AIBN Azo bisiso butyronitrile
AM Acrylamide
AN Acrylonitrile
APS Ammonium persulfate
ATRP Atom transfer radical polymerization
CAN Ceric ammonium nitrate
CG Cashew gum
CTKP Carboxymethyl tamarind kernel polysaccharide
DSC Differential scanning calorimetry
EA Ethyl acrylate
EMA Ethyl methacrylate
FG Fenugreek gum
FTIR Fourier transform-infra red
GA Gum acacia
GG Guar gum
GGt Gum ghatti
GK Gum kondagogu
GRAS Generally regarded as safe
HPMC Hydroxy propyl methylcellulose
HPTS Hydroxypropyl tapioca starch
IPN Interpenetrating polymer network
ITG Iranian tragacanth gum
KGM Konjac glucomannan
KPS Potassium persulfate
KSAP Konjac glucomannan-based superabsorbent polymer
LBG Locust bean gum
MA Methacrylamide
MBA N,N′-methylene bisacrylamide
MMA Methyl methacrylate
mPEG Methylated poly(ethyleneglycol)
NMR Nuclear magnetic resonance
NPVP N-poly vinylpyrrolidone
NVP N-vinylpyrrolidone
OG Okra gum
PAA Polyacrylic acid
PAGA Poly(2-acrylamidoglycolic acid)
PAM Polyacrylamide
PAN Poly(acrylonitrile)
PANI Poly(aniline)
PANI Polyaniline
PAO Polyamidoxime
PCL Polycaprolactone
PCMGG Partially carboxymethylated guar gum
PDMAEMA Poly(dimethyl aminoethyl methacrylate)
PEC Polyelectrolyte complexes
PhMA Phenyl methacrylate
PMA Poly(methacrylic acid)
PMAD Poly(methacrylamide)
PMMA Polymethylmethacrylate
Psy Psyllium polysaccharide
ROP Ring opening polymerization
SEM Scanning electron microscopy
TG Tragacanth gum
TGA Thermogravimetric analysis
TKGM Thermoplastic konjac glucomannan
TKP Tamarind kernel polysaccharide
TS Tapioca starch
UV Ultraviolet
VAc Vinyl acetate
XRD X-ray diffraction
1. Introduction
The usage of naturally occurring materials is extremely enhanced in almost all spheres of human lives during the past few decades (Lloyd et al., 1998; Hasnain et al., 2010; Pal and Mitra, 2010; Nayak and Pal, 2012; Pal et al., 2012). Currently, synthetic products are being replaced by natural materials due to their excellent biodegradability, sustainable production, low cost, high abundances, etc. (Nayak et al., 2013a,b). Plant polysaccharides are naturally occurring carbohydrate macromolecules, which are extracted from different plant parts like fruits, rhizomes, leaves, pods, seeds, peels, etc. (Nayak and Pal, 2015). They are physicochemically as well as structurally diverse, encompassing a variety of backbones/functional groups (Kaur et al., 2012b; Nayak et al., 2013c; Nayak et al., 2015). Like other natural products, plant polysaccharides also exhibit several advantages (Avachat et al., 2011; Nayak et al., 2012; Pal and Nayak, 2015), which eventually make possible for different industrial uses like food, confectionary, biomedical, pharmaceutical, cosmeceutical, chemical engineering, paper-making, and so on (Nayak and Pal, 2012; Prajapati et al., 2013). However, most of the plant polysaccharides in their native form demonstrate unsatisfactory outcomes due to their uncontrolled rate of hydration, variable aqueous solubility, pH, rheological alterations during storage, pH responsive swelling, possibilities of contaminations by microbial attack, etc. (Nayak and Pal, 2015; Nayak, 2016).
Many research laboratories have made great headway to modify plant polysaccharides chemically by introduction of various functional groups (viz. –COOH, –NH
2, –SH, –NH
4+Cl
−, –SO
32−, –OC
2H
5, –OCH
3, –CH
CH
2, –C
O(NH
2, etc.)) (
Wang and Wang, 2013;
Thakur and Thakur, 2014,
2015) to inculcate desired functional properties. A wide variety of structural compositions of plant polysaccharides allow appropriately tailoring their structures (
Kaur et al., 2012a,
b;
Manchanda et al., 2014) through various chemical reactions such as cross-linking (
Maiti et al., 2011;
Sarmah et al., 2011...