Cellulose Studies. Part XVI. The Reaction of Cellulose with Formaldehyde

Abstract

A new method for reacting cellulose and formaldehyde in the vapor phase using acid catalysts is described. Acids as weak as boric acid were effective in introducing up to 6% covalently bonded formaldehyde. The results of reaction conditions where catalyst concentration ranged from 1%-10% and reaction temperature ranged from 110°-150°C are presented.A chemical investigation of the structure of the product of the reaction showed that formalde-, hyde preferentially substitutes the secondary hydroxyl groups of cellulose to yield a 'structure represented by the general formula R~O-CH2-O~R', where R and R' indicate glucose residues in parallel chains. * This article is based on a thesis submitted by Robert E.

Surface areas of cottons and modified cottons before and after swelling as determined by nitrogen sorption

“…Th e former product was resistant to dyeing with direct dyes, whereas the latter resembled th e original cotton in dyeing b ehavior. Both the dye-resistant character of this m ethylenated cotton, and the relatively small increase in specific surface, around 3 m 2 /g, produced by swelling and exchange of th e methylenated product from air-dried cotton, support the conclusion that the formaldehyde is present in the form of crosslinks th at interfere wi th swelling [11,12]. The larger incr ease in specific surface, approximately 19 m 2 /g, produced by swelling of th e methylenated product from prewet cotton indicates that the position of the crosslinks in this product is such that the cotton retains much but not all of its swelling ability.…”

Permanently amorphous cellulose

“…This value confirms the accessibility of 89% previously measured on amorphous cellulose a t a relative humidity of 50%. 6 It is interesting to note that in spite of the amorphous diffraction pattern the accessibility was not 1 0 0~o . This is a further demonstration of the absence of a quantitative correlation between crystallinity aa measured by x-ray diffraction and accessibility determined by hydrogen exchange.…”

Methode zur Konstitutionsaufklärung der Reaktionsprodukte der Umsetzung von Cellulose mit Formaldehyd. 18. Mitteilung über textilchemische Untersuchungen [1]

“…1967. netzter Baumwolle befassten wir uns seitdem rnit der Frage, welche der drei Hydroxylgruppen der Anhydroglucoseeinheiten bei der Reaktion der Cellulose mit Formaldehyd, dem einfachsten Vernetzungsmittel fur Raumwolle, reagieren. Dieses Problem ist bereits 1952 durch WAGNER & P~c s u [3], 1964 durch ARAKI [4] und Jow.m.m K. RIVLIN [5] sowie neuerdings durch SMITH et al [6] bearbeitet worden Diese Autoren haben die rnit Forrnaldehyd vernetzte Cellulose permethyliert und sowohl die 1,4'-glucosidischen Bindungen der Cellulose-Ketten wie auch die acetalartigen Bindungen der Methylen-oder Polyoxymethylen-Briicken des Formaldehyds anschliessend saurehpdrolytisch gespalten. Im Gegensatz zu ARAKI und zu RIVLIN gelang WAGNER und PACSLI einc Auftrennung der bei tier Hydrolyse auftretenden Mono-, Di-, Tri-und Tetramethylglucosen nicht vollstandig.…”