Cellulose cotton

A. Fundamental Study ofi the Pyrolysis ofi Cotton Cellulose to Provide Infiormation Neededfor Improvement ofiFlame Kesistant Treatmentsfior Cotton, Pinal Report 1959—1964 on PL 480 Project No. URE-29-(20)-9 Grant No. PG-UK-108-59, The Cotton, Silk and Man-Made Pibers Research Association, Didsbury, UK, 1964. 

Treatment of the algal cellulose (mixture of la—IP) from Valonia in ethylenediamine to give Cellulose IIIj simultaneously induced sub fibrillation in the initial microfihril (75). Thus crystallites 20 nm wide were spHt into subunits only 3—5 nm wide, even though the length was retained. Conversion of this IIIj back to I gave a material with an electron diffraction pattern and nmr spectmm similar to that of cotton Cellulose ip. 

Table 3. Relative Availabilities of Hydroxyl Groups of Cotton Cellulose Throughout Growth and Weathering ...

By using this technique acrylamide, acrylonitrile, and methyl acrylate were grafted onto cellulose [20]. In this case, oxidative depolymerization of cellulose also occurs and could yield short-lived intermediates [21]. They [21] reported an electron spin resonance spectroscopy study of the affects of different parameters on the rates of formation and decay of free radicals in microcrystalline cellulose and in purified fibrous cotton cellulose. From the results they obtained, they suggested that ceric ions form a chelate with the cellulose molecule, possibly, through the C2 and C3 hydroxyls of the anhy-droglucose unit. Transfer of electrons from the cellulose molecule to Ce(IV) would follow, leading to its reduction... 

Partial carboxymethylation of wood pulp significantly increases its susceptibility toward grafting with acrylonitrile using the ceric ion as the initiator 146]. Studies dealing with grafting of various vinyl monomers, such as acrylonitrile, methylmethacrylate, and acrylamide, onto partially carboxymethylated cotton cellulose using tetravalent cerium as the initiator have been reported [47]. 

Naturally occurring fibers such as cotton, cellulose, etc., have short whiskers protruding from the surface, which help to give a physical bond when mixed with rubber. Glass, nylon, polyester, and rayon have smooth surfaces and adhesion of these fibers to the rubber matrix is comparatively poor. In addition, these synthetic fibers have chemically unreactive surfaces, which must be treated to enable a bond to form with the mbber. In general, the fibers are dipped in adhesives in the latex form and this technology is the most common one used for continuous fibers. The adhesion between elastomers and fibers was discussed by Kubo [128]. Hisaki et al. [129] and Kubo [130] proposed a... 

Modified Plant Wood pulp and cotton Cellulose derivatives ... 

Figure 10.27 Effect of sequestering agent concentration on the decomposition of hydrogen peroxide and degree of polymerisation of cotton cellulose [236]...

Figure 10.30 Functional groups formed by oxidising cotton cellulose with sodium hypochlorite over the pH range 5-10 [235]...

Table 10.39 Pretreatments to modify cotton cellulose by substitution reactions [393]...

A more radical approach to pretreatment reverses the conventional reactive dyeing concept by preparing a reactive cotton cellulose capable of reacting covalently with suitable dyes containing, for example, aliphatic amino groups. In an initial attempt, cotton was... 

Imaginative use has been made of triazine and sulphatoethylsulphone reactive dye chemistry in the application of pretreatments to nylon [405]. The concept resembles that used to make cotton cellulose reactive before dyeing with aminoalkylated dyes, as discussed earlier (Schemes 10.67 and 10.68). In this case, nylon becomes the reactive partner by pretreatment with a reactive multifunctional crosslinking agent ... 

Multilayer deposition of halloysite is possible not only on large solid surfaces but also on soft biological surfaces such as wood or cotton cellulose microfibers (Figure 14.18). This coating allows a drastic increase in the porosity of the fibers and materials made from them (paper and textile). 

Barsha and Hibbert16 also demonstrated by meins of methylation, acetylation, acetolysis and hydrolysis experiments that the membranes synthesized by the action of A. xylinum on D-fructose and on glycerol were chemically identical with cotton cellulose. 

Further confirmation of the identity of bacterial and plant celluloses has been obtained by x-ray studies. From dried membranes prepared by the action of A. xylinum on sucrose, Eggert and Luft18 obtained x-ray diagrams similar to those of cotton cellulose. Hibbert and Barsha16 showed that a chloroform solution of the triacetate of cellulose... 

Since bacterial cellulose from all suitable carbohydrate substrates i8 identical with natural cellulose, its industrial importance20 is obvious. Relatively large amounts of bacterial cellulose were produced in Germany during the first World War. More recently products similar to parchment, mercerized cotton, cellulose nitrate,21 acetate14 and viscose rayons have been produced from bacterial cellulose. 

For cotton cellulose such indirect measurements indicated first a decreasing rate of heat release with time to a minimum reached after 8 hours at 165°C, followed by an increasing rate with time (15, 16) In this case, the minimum rate was 0.7 kcal/kg h, which is about half our initial rate for bleached kraft at that temperature here. Also, this minimum rate was found to be greater for viscose cellulose (17). In oxygene the rate was double that in air and still showed the pronounced minimum level. 

The differences in reactivities of the three hydroxyl groups towards methylation do not seem to be affected by other cellulose chains in heterogeneous reactions, as similar ratios were found for both heterogeneous and homogeneous reactions.286 However, in work involving the repeated, heterogeneous methylation of cotton cellulose, the relative reactivities of the hydroxyl groups have been... 

More recently, the fixation efficiency on cotton of Cl Reactive Red 177 (7-43) and its 4-carboxyphenylazo analogue in the presence of various carbodiimides (including 7-44 and 7.45) was investigated, as well as homogeneous reactions of selected carboxylic acids with alcohols (including acetylcellulose in acetone). The carboxylated dye reacted more effectively with cotton cellulose in the presence of cyanamide rather than dicyandiamide,... 

The final product was subjected to ferric chloride-hydrochloric acid treatment in the same manner as commercial glucose and starch. A linear carbon dioxide-time relationship was observed which was practically identical with that for starch. In other words purified cotton cellulose, on relatively complete hydrolysis, appeared to give glucose in a... 

Wakelin, J. H., Virgin, H. S., and Crystal, E. (1959). Development and comparison of two X-ray methods for determining the crystallinity of cotton cellulose. Journal of Applied Physics. 30,1654-1662. 

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