摘要:
A stabilized, sparsely esterified chitin polymer which has been dissociated and purified from a naturally occurring calcified chitin/protein matrix, and which substantially retains the structural features of the chitin matrix in that it comprises elongated fibers which are rapidly and quantitatively recognized by enzymes specific for naturally occuring chitin. The chitin polymer is made by a method in which the naturally occuring matrix is first decalcified and deproteinized, and then the chitin is dispersed and stabilized in a cold dilute ester-forming acid before being recovered. The polymer is useful in various processes involving reactions with enzymes specific for naturally occurring chitin, and as a feedstock for producing products resulting from action of such enzymes.
摘要:
Diagnostic reagents and a method for increasing the sensitivity of chemical and enzymatic analysis. In particular, an improved reagent and method wherein the sensitivity of the spectral analysis is improved by the addition of a water-soluble inclusion compound (cyclodextrin).
摘要:
Method of treating cellulose to increase its chemical and biological reactivity comprising contacting cellulose-containing material with volatile celluloseswelling agent having a vapor pressure greater than atmospheric pressure at ambiant temperature. said contact being carried out at nearly ambient temperature and a pressure greater than atmospheric and thereafter reducing the pressure to atmospheric to cause the swelling agent to boil and explode the fiber structure of the cellulosic containing material.
摘要:
La présente invention concerne de nouvelles solutions de polymères permettant l'obtention d'articles en forme tels que fils et fibres, films, feuilles, etc.. Ces solutions sont constituées de cellulose de degré de polymérisation au moins 200, de polymère à base d'acrylonit- rile, de diméthylsulfoxyde et de formaldéhyde, avec un rapport pondéral cellulose/polymère acrylique de 0,05 à I, de préférence 0,1 à 1, un rapport formaldéhyde/cellulose de 0,2 à 2, et une concentration totale de 12 à 30 %, de préférence 18 à 26 %. De telles solutions conviennent particulièrement pour l'obtention de filaments constitués de fibrilles orientées sensiblement suivant l'axe de la fibre et étroitement entrecroisées, les macromolécules de cellulose étant partiellement engagées dans un réseau cristallin caractéristique de la cellulose II. Les filaments possèdent des propriétés intéressantes pour une utilisation textile.