62 REPORTS ON THE STATE OF SCIENCE.—1918. 
1 Lunge, Journ. Amer, Chem. Soc., 23, 527 (1901). 
2 Berl & Klaye, Mon. Sci. (4), 23, 103. 
18 Mosenthal, Journ. Soc Chem. Ind., 292 (1904). 
M4 Cross & Bevan, Cellulose (pp. 38-41) Researches, 1895-1900, p. 43 ; 1900, 3, 
p. 97. 
18 Saposchnikow, Journ. Russ. Phys. Chem. Soc., 35, 669, (1904) ; 36, 518, (1905) ; 
38, 1186 (1906). 
(See also 7th Internal Cong. Appl. Chem., London, p. 19). 
16H. Justin Mueller, Koll. Zeit., 2,49 (1907). 
7 Arthur Muller, idid., 2, 173 (1907). 
18 Mosenthal, Jowrn. Soc. Chem., Ind. 443 (1907). 
19 Piest, Zeit. angew. Chem., 22, 1215 (1908) ; 23, 1009 (1910). 
* Berl, Zeit. 7. Scheiss and Sprengwesen, 4, 81 (1909) ; 5, 254 (1910). 
21 Schwartz, Koll. Zeit, 12, 32 (1918). 
*2 Ambronn, Koll. Zeit, 13, 200 (1913), 
*3 Knecht & Lipschitz, Jowrn. Soc. Chem. Ind. 33, 116 (1914). 
Organic Esters of Cellulose. Cellulose Acetates. 
Cellulose forms esters of acetic acid when treated with acetic 
anhydride in presence of condensing agents.” The maximum 
amount of acetyl groups which can be introduced without modifica- 
tion of the cellulose complex corresponds to one half of the number 
of carbon atoms present in the cellulose. It is possible to introduce 
more acetyl groups but considerable modification in the cellulose is 
produced. 
The solubility of cellulose acetates and the viscosity!® of its 
solutions varies with the conditions of preparation in a more irregular 
manner than the nitrates. Even under apparently identical con- 
ditions, different results are sometimes obtained. The ease with 
which the colloidal state of the cellulose in cotton fibres is changed is 
possibly the explanation of these differences. 
Cellulose Formate. 
Cellulose forms derivatives with formic acid quite readily in the 
presence of condensing agents.4!® It has been stated’ that cellulose 
formate is produced when oxalic acid solution is dried on cotton, 
The properties of cellulose formates have not yet been thoroughly 
studied. 
Of other esters of cellulose the following have been prepared :— 
Cellulose propionate,”! butyrate,22 aceto-butyrate,”’ palmitate,” 
phenyl-acetate,”” phospho-formate,”* aceto-nitrate,” aceto sulphate,” 
nitro-sulphate,?* 7 2° sulphonates, ete. 
Recently, methylated celluloses®” #! have been prepared, and their 
products of hydrolysis carefully studied. Nastjukoff*? claims to have 
prepared phenylated celluloses. 
(BH) Cellulose Acetates. 
1 Cross & Bevan, Cellulose, p. 34. 
* Schwalbe, Die Cellulose, p. 316. 
3 Worden, Nitrocellulose Industry, pp. 984-1004. 
‘ Schutzenberger, Comp. Rend. 61, 488 (1869); 68, 814 (1870). 
» Franchimont, Ber. 12, 1264, 1941, 2099 (1879). 
° Cross & Bevan, Trans. Chem. Soc.'5%, 1 (1890); 6'7, 433 (1895) 
7 Thiele, Jowrn. Soc. Dyers 3 Cols. 24, 294 (1908). 
° Cross & Briggs, ibid. 24, 189 (190s). 
® Schwalbe, Zeit. angew. Chem. 23, 435 (1910). 
