Hydroxypropylation reduces gelatinization temperature of corn starch for textile sizing

Abstract

A series of hydroxypropylated starch (HPS) that can be dissolved in water at 60-65℃ was obtained via two-step method in water system from corn starch. The structure and property of the HPS and its gelatinization temperature were characterized by Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance spectroscopy ( 1 H NMR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and transmission electron microscope (TEM). It was concluded that hydroxypropyl mainly bonded on the hydroxyl group at C2 position from anhydroglucose unit of starch in the form of C-O-C, and the substitution level at C6 position was slightly higher than that at C3 position; and the crystallinity of starch decreased from 52.41% to 29.4% due to the introduction of hydroxypropyl and was confirmed by XRD. At the same time, the grooves on the surface of starch granules were observed by SEM. The above-mentioned two synergism promoted the permeation and transmission of water molecules in the starch microstructure. Moreover, the gelatinization temperatures and enthalpy of synthetic HPS was lower than that of raw corn starch, as further confirmed by DSC. This caused the HPS with a molar substitution greater than 0.1 soluble in water at 65℃, and the dissolution state was similar to that of at 95℃ (transmittance above 55%), as well as exhibited high slurry stability. Interestingly, compared with the raw starch, the HPS film showed excellent mechanical property at the relative humidity of 65%, which could be attributed 2 to the hydrophilic ether bond and the flexible alkyl chain bonded on the structure of starch. This study will provide a new way for the preparation of high performance starch size for sizing yarn at medium low temperature.

Cationic etherification modification of corn starch and its sizing property

“…All the SA- g -GTA samples prepared were named in the form of SA- g -GTA-1, SA- g -GTA-2, SA- g -GTA-3, SA- g -GTA-4, and SA- g -GTA-5, respectively, in which the meaning of the number ( n ) was the amount of GTA added (the molar ratio of GTA to glucose residue of starch is n :10). 20…”

“…The supersolution was poured onto a polyester plastic container and dried at 40°C to determine the weight of the dispersed sample. The dispersion of the sample was determined by the following equation (6): 20 where D is the dispersion of the starch sample, B is the dry weight of dispersed etherified starch, and A is the total dry weight of etherified starch added.…”

“…This phenomenon could be explained by the intramolecular and intermolecular hydrogen bonds, chemical bonds, and crystalline structure of starch that had been disrupted under the effect of the alkaline condition and GTA, which was similar to the analysis results of the conclusion of previous studies. 20 Moreover, compared with NA, the etherified modification process could increase the thermal stability of the starch substrate by lengthening its side chain. This also provided reliable evidence for the etherification of the starch chain.…”

Polysaccharides and Metal Nanoparticles for Functional Textiles: A Review

“…As a versatile polymer, starch is used in a variety of industrial applications, including food, paper, adhesives, paints, coatings, pharmaceuticals, and textiles [ 99 ]. Regarding the textile sector, starch is widely used as a bio-based sizing agent in textiles due to its satisfactory adhesion to fibers and good film properties, which protect yarns from mechanical abrasion [ 100 , 101 ].…”

Application of hydroxypropylated crosslinked starch from the grains of Oryza sativa L. as potential disintegrant in compressed solid dosage form

“…It also helps to hold and keep the tablet particles together due to their high swelling capacity even in low concentrations (Pahwa and Gupta, 2011). Acetylation and hydroxypropylation as individual modification techniques have been applied to rice and other starches that are carried out to overcome undesirable characteristics and improve their physico-chemical properties (Colussi et al, 2014;Granza et al, 2015;Shen et al, 2021). Additionally, acetylation improves paste clarity, flow properties, and increased swelling capacity (Lawal, 2004), while carboxymethylation of starch may increase water solubility, lowered gelatinization temperature, and paste stability (Kunle, 2019).…”