The Reaction of Forxnaldehyde with Cellulose

It is known that certain resins when applied to cellulosic fibers will impart wrinkle recovery improvement to the fabric. This improved property is shown to vary directly with the amount of chemical reaction between the resin and the cellulose. The evidence for this is obtained primarily from infrared spectra. These spectra were obtained from cellophane films to which resin had been applied by techniques known to give varying wrinkle recovery. The type of chemical reaction with cellulose is shown to be the same for a number of resins and for formaldehyde.

Section: A Formaldehydesupporting

confidence: 90%

“…Steele [6] has made some observations of the infrared spectrum of formaldehyde on thin, 2.5 to 5.0 jU, cellulose films. These films were prepared by deacetylating films of cellulose acetate cast from acetone solution on mercury.…”

Section: A Formaldehydementioning

confidence: 99%

Cellulose Interactions with Certain Textile Resins

Lineken¹,

Davis²,

Jorgensen³

1956

“…Wagner and Pacsu [21], in their study, showed that formaldehyde reacted preferentially with the secondary hydroxyl groups and that the cross-links were not polymeric. The latter conclusion has been supported by the results of infrared spectral studies made by Steele [20].…”

Section: Introductionmentioning

confidence: 58%

The Reaction of Formaldehyde with Cellulosic Fibers

Woo

Dusenbury

Dillon

1956

The acid-catalyzed reaction of formaldehyde with cellulose has been studied under conditions comparable to those of formaldehyde treatments carried out in textile finishing plants. Cotton, Fortisan, and viscose rayon fabrics were treated at different padbath pH values (2.0, 2.2, and 2.4) and formaldehyde concentrations, at different temperatures (110°, 120°, and 130° C.), and for different periods of time.At the higher pH values of 2.2 and 2.4, the cross-linking reaction seems to take place primarily in the amorphous regions of the fibers; at the lowest pH, a very rapid reaction occurs in the amorphous regions, accompanied and followed by diffusion of formaldehyde into the crystalline regions which controls the observed reaction rate. Both the rate and extent of reaction appear to depend on the state of internal order of the cellulosic material, being least for cotton, the material of highest crystallinity. Fortisan and viscose rayon have about the same degree of crystallinity, but the reaction with Fortisan is more rapid which causes the extent of reaction at later times to be greater than that observed for viscose rayon. Two possible explanations are either that the higher orientation of Fortisan facilitates the cross-linking process or that recrystallization occurs during acid hydrolysis, and viscose rayon has a relatively higher rate of recrystallization. The results of X-ray diffraction studies carried out on the variously treated cellulosic fibers are consistent with the proposed reaction mechanisms.

“…Previous workers [5,6,15,33] have also concluded, mainly from indirect evidence, that formaldehyde reacts selectively or predominantly with the secondary hydroxyl groups of the cellulose.…”

Section: Resultsmentioning

confidence: 99%

Investigations on the Chemical Constitution of Cotton Cross-Linked With Formaldehyde

Patel

Rivlin

Samuelson

et al. 1968

Cotton was cross-linked with formaldehyde by various methods (Form D, W, and V processes). The cellulose formals containing 1-4% formaldehyde were permethylated by a series of dimethylsulfate/dimethylsulfoxide treatments followed by exchange methylations of sodium cellulosate with methyl iodide in n -butanol. The permethylated cellulose formals were hydrolyzed in sulfuric acid and the methyl glucoses thus formed were reduced to the respective sorbitols. The mixture of these sorbitols, after suitable blocking of the free hydroxyl groups, was separated and quantitatively analyzed by gas-liquid phase chromatography. The results indicate a decreasing reactivity of the hydroxyl groups in the sequence C(6)>C(2)>C(3), the occurrence of 2,3-methylene linkages, and an average length of the oxymethylene cross links of between 1,3 and 2,0. The constitution of these cellulose formals is influenced by the type of formaldehyde application. Discrepancies between our results and those of other investigators are explained by their incomplete methylation, substitution of methylene cross links by methyl groups in permethylations, and incomplete separation of the degradation products.