The Function of Swelling in the Finishing of Cotton

1969 ◽  
Vol 39 (6) ◽  
pp. 548-559 ◽  
Author(s):  
R. Jeffries ◽  
J. O. Warwicker
Keyword(s):  
Hydrogen Bond ◽  
Caustic Soda ◽  
Structural Changes ◽  
Cellulose Ii ◽  
Cellulose I ◽  
X Ray ◽  
Swelling Agent ◽  
Degree Of Swelling ◽  
Finishing Processes ◽  
Ray Methods

The mechanism of the interfibrillar and intrafibrillar swelling of cotton has been investigated by infrared and x-ray methods. Emphasis is on swelling in caustic soda, but other reagents are also considered. The presence of intrafibrillar swelling can be shown by detection of intermediate complex formation, while the swelling agents are present. The swelling behavior and the structural changes produced in the cotton are modified by the effects of tension and also by the presence of additives in the swelling solution. Whether the swelling complexes are intermediate in the conversion of cellulose I to cellulose II, or a reconversion to cellulose I results on washing out the swelling agent and drying, depends on the degree of swelling at different stages of the process. Intrafibrillar swelling is usually accompanied by an increase in the hydrogen-bond disorder, even if reconversion to cellulose I takes place, and the detection of this increase in disorder by ir-deuteration methods may be the only indication of an intrafibrillar swelling process. An explanation of the observed behavior is put forward in terms of the concept of cellulose sheets. The ideas developed from a study of the swelling of cotton by caustic soda and other swelling agents have been used in explaining the effects found in the mercerization and other finishing processes applied to cotton.

scholarly journals Stable, metastable and unstable cellulose solutions

2017 ◽  
Vol 4 (8) ◽  
pp. 170487 ◽  
Author(s):  
Marta Gubitosi ◽  
Pegah Nosrati ◽  
Mona Koder Hamid ◽  
Stefan Kuczera ◽  
Manja A. Behrens ◽  
...  
Keyword(s):  
Microcrystalline Cellulose ◽  
Small Angle ◽  
Supersaturated Solution ◽  
Cellulose Ii ◽  
Cellulose I ◽  
Tetrabutylammonium Hydroxide ◽  
X Ray ◽  
Stable Regime ◽  
X Ray Scattering ◽  
A Minor

We have characterized the dissolution state of microcrystalline cellulose (MCC) in aqueous tetrabutylammonium hydroxide, TBAH(aq), at different concentrations of TBAH, by means of turbidity and small-angle X-ray scattering. The solubility of cellulose increases with increasing TBAH concentration, which is consistent with solubilization driven by neutralization. When comparing the two polymorphs, the solubility of cellulose I is higher than that of cellulose II. This has the consequence that the dissolution of MCC (cellulose I) may create a supersaturated solution with respect to cellulose II. As for the dissolution state of cellulose, we identify three different regimes. (i) In the stable regime, corresponding to concentrations below the solubility of cellulose II, cellulose is molecularly dissolved and the solutions are thermodynamically stable. (ii) In the metastable regime, corresponding to lower supersaturations with respect to cellulose II, a minor aggregation of cellulose occurs and the solutions are kinetically stable. (iii) In the unstable regime, corresponding to larger supersaturations, there is macroscopic precipitation of cellulose II from solution. Finally, we also discuss strong alkali solvents in general and compare TBAH(aq) with the classical NaOH(aq) solvent.

Eco-Friendly Preparation of Nanofibrillated Cellulose from Water Hyacinth Using NaOH/Urea Pretreatment

2020 ◽  
Vol 990 ◽  
pp. 225-230
Author(s):  
Kraiwit Pakutsah ◽  
Duangdao Aht-Ong
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Water Hyacinth ◽  
Aqueous Suspension ◽  
Nanofibrillated Cellulose ◽  
Cellulose Ii ◽  
Cellulose I ◽  
X Ray ◽  
Transmission Electron ◽  
Water Hyacinth Fiber

In this work, we described an effective approach to prepare nanofibrillated cellulose (NFC) with cellulose II structure under mild condition. Firstly, the water hyacinth (WH) was subjected to a series of a two-step chemical treatment, NaOH/urea pretreatment, and mechanical defibrillation at different defibrillation times. After that, raw water hyacinth fiber (RWF), bleached water hyacinth fiber (BWF), NaOH/urea pretreated water hyacinth fiber (PWF), and the resulting NFC were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD) as well as rheological measurements. It was found that RWF and BWF exhibited cellulose I crystal structure, whereas PWF and the obtained NFC possessed cellulose II crystal structure. FTIR analysis confirmed the evidence that no other chemical reactions preferentially occurred during both NaOH/urea pretreatment and mechanical defibrillation. As evidenced by rheological properties analysis, the NFC aqueous suspension with a gel-like structure demonstrated a shear-thinning behavior. The obtained NFC could potentially be utilized as a reinforcement for polymeric composites.

scholarly journals Engineering short, strong hydrogen bonds in urea di-carboxylic acid complexes

CrystEngComm ◽  
2014 ◽  
Vol 16 (35) ◽  
pp. 8177-8184 ◽  
Author(s):  
Andrew O. F. Jones ◽  
Charlotte K. Leech ◽  
Garry J. McIntyre ◽  
Chick C. Wilson ◽  
Lynne H. Thomas
Keyword(s):  
Hydrogen Bond ◽  
Carboxylic Acid ◽  
Hydrogen Bonds ◽  
Neutron Diffraction ◽  
Structural Changes ◽  
Acid Amide ◽  
Molecular Complexes ◽  
Temperature Dependent ◽  
X Ray ◽  
Methyl Substitution

The persistence of the acid⋯amide heterodimer and the effect of methyl substitution on the short strong O–H⋯O hydrogen bond is investigated in urea and methylurea di-carboxylic acid molecular complexes. Temperature dependent structural changes are also reported utilising X-ray and neutron diffraction in tandem.

scholarly journals CELLULOSE NANOCRYSTALS FROM UNDERUTILIZED POLYTHIA LONGIFOLIA SEED

2017 ◽  
Vol 14 (27) ◽  
pp. 10-18
Author(s):  
Adewale ADEWUYI ◽  
Fabiano Vargas PEREIRA
Keyword(s):  
Adsorption Capacity ◽  
Cellulose Nanocrystals ◽  
Cellulose Ii ◽  
X Ray Diffraction ◽  
Cellulose I ◽  
Sem Images ◽  
X Ray ◽  
Potential Source ◽  
Swelling Capacity ◽  
Water Holding

Polythia longifolia seed (PL), an underutilized seed in Nigeria was used as a starting material to prepare Polythia longifolia cellulose nanocrystals (PLN). Polythia longifolia cellulose (PLC) was first isolated and subjected to sulfuric acid hydrolysis followed by ultrasonication and homogenization. PL, PLC and PLN were characterized using Fourier transformed infrared (FTIR), x-ray diffraction (XRD), thermogravimetric analysis (TG) and scanning electron microscopy (SEM). PLC and PLN were evaluated for their heavy metal adsorption capacity, swelling capacity, water holding capacity and oil holding capacity. SEM images reveal elliptical granules of PLN while XRD shows a mixture of polymorphs of cellulose I and cellulose II. PLN displayed a better water holding, oil holding and swelling capacities. PLN also exhibited a higher adsorption capacity towards Cu2+ and Pb2+ ions than PLC. The results showed that Polythia longifolia seed can serve as a potential source of cellulose nanocrystals which might be useful in other applications.

scholarly journals AN INVESTIGATION OF THE STRUCTURAL CHARACTERISTICS OF MODIFIED CELLULOSE FROM ACACIA PULP

2017 ◽  
Vol 55 (4) ◽  
pp. 452 ◽  
Author(s):  
Doan Minh Khai ◽  
Phan Duc Nhan ◽  
Trinh Duc Hoanh
Keyword(s):  
Hydrogen Bond ◽  
Structural Characteristics ◽  
Crystalline Size ◽  
Cellulose Ii ◽  
Cellulose I ◽  
Modified Cellulose

The structural characteristics of the modified celluloses from acacia pulp in Vietnam were investigated and compared to others. The total crystalline index (TCI), the lateral order index (LOI) and the hydrogen bond intensity (HBI) were evaluated by the FTIR. The size of crystallites were considered by XRD. The TCI, LOI and HBI of modified acacia cellulose I are found. The crystalline size of modified acacia cellulose I and cellulose II are found.

scholarly journals X-Ray Investigations on Cellulose II and Mixtures of Cellulose I and II. 2. Lateral Order in Cellulose II.

1960 ◽  
Vol 14 ◽  
pp. 689-691 ◽  
Author(s):  
Jon Gjønnes ◽  
Nico Norman ◽  
J. Åselius ◽  
Susanne Refn ◽  
Gertrud Westin
Keyword(s):  
Cellulose Ii ◽  
Cellulose I ◽  
X Ray

Cell-wall studies in the Chlorophyceae. I. A general survey of submicroscopic structure in filamentous species

1952 ◽  
Vol 140 (899) ◽  
pp. 244-274 ◽  
Keyword(s):  
Fibrillar Structure ◽  
Cellulose Ii ◽  
Cellulose I ◽  
General Survey ◽  
Random Orientation ◽  
Submicroscopic Structure ◽  
X Ray ◽  
Filamentous Green Algae ◽  
Large Bulk ◽  
The Status

The paper constitutes a survey of the fine structure of the walls in about sixty species of filamentous green algae, as revealed chiefly by the methods of X -ray analysis. With some species use has also been made of the polarizing microscope and of staining reactions. I t is known that wall constituents in the algae are very variable, and one aim of the investigation has been to systematize this variation. The chief aim has been, however, to attempt to delimit the range of types which show the ‘crossed fibrillar’ structure typical of Valonia . It has been found possible, on the basis of wall characters, to divide the algae investigated into three rather ill-defined groups, as follows: Group 1. The algae of this group contain native cellulose (cellulose I) as a major skeletal substance. The cellulose is highly crystalline and shows the ‘crossed fibrillar’ organization. Members of this group are found only in the Cladophorales, and in a few members of the Siphonales. Group 2. The skeletal substance of the walls in this group possess intermolecular spacings which approximate to those of mercerized cellulose (cellulose II). There is some evidence that, in some cases at least, the substance is not mercerized cellulose but some cellulose derivative. It is poorly crystalline and normally in random orientation. The large bulk of the algae fall into this group, which includes the Spongomorpha section of Cladophora . Group 3. This is a small, heterogeneous collection of algae in which the skeletal substance either is not cellulose in any known form, or shows abnormalities, in what otherwise might be an X-ray diagram of cellulose, which make identification difficult. Prominent among the latter may be mentioned Spirogyra and Vaucheria . It is suggested that wall studies of this kind would repay consideration by taxonomists, particularly as regards the status of the Cladophorales,

scholarly journals Terahertz Time-domain Spectroscopy as a Novel Tool for Crystallographic Analysis in Cellulose: Cellulose I to Cellulose Ii, Tracing the Structural Changes Under Chemical Treatment

2021 ◽  
Author(s):  
Han Wang ◽  
Hiroki Kataoka ◽  
Satoru Tsuchikawa ◽  
Tetsuya Inagaki
Keyword(s):  
Absorption Coefficient ◽  
Time Domain ◽  
Structural Changes ◽  
Crystalline Lattice ◽  
Thz Radiation ◽  
Cellulose Ii ◽  
Cellulose I ◽  
Terahertz Time Domain Spectroscopy ◽  
Time Domain Spectroscopy ◽  
Thz Absorption

Abstract Terahertz time-domain spectroscopy (THz-TDS) has expanded possibilities in cellulose crystallography research, as THz radiation detects most intermolecular vibrations and responds to the phonons of crystalline lattices. In this study, we traced the transformation of the cellulose crystalline lattice from cellulose I to cellulose II by THz-TDS and X-ray powder diffraction. Cellulose II was obtained by treating cellulose I with NaOH of different concentrations (0 wt%–20 wt%, at 2 wt% intervals). The THz absorption coefficient spectra of cellulose II showed three characteristic peaks (at 1.32 THz, 1.76 THz, and 2.77 THz). The THz absorption coefficient spectra of cellulose II treated with 20-wt% NaOH and cellulose I without NaOH treatment were fitted by a seventh-order Fourier series. Thus, the THz absorption coefficient spectra of samples treated with NaOH of other concentrations could be considered a combination of these two fitted profiles of cellulose I and cellulose II, multiplied by different coefficients. Furthermore, the coefficients could reflect the relative contents of cellulose I and cellulose II in the samples.

Sign in / Sign up

Export Citation Format

Share Document