62 REPORTS ON THE STATE OF SCIENCE.—1917. 
product thus obtained, which contains about 10 per cent. of nitrogen, and regards it as 
a glycoprotein. 
Eaton and Grantuam found that if freshly coagulated latex be allowed to remain 
for a few days before washing or rolling therubber eventually obtained is rapidly-curing 
and possesses considerably superior physical properties after vulcanisation (‘ Agric. 
Bull. F.M.S8.’ 1915, 8, p. 442, and 4, p. 58, also ‘Journ. Soc. Chem. Ind.’ 1916, 35, p. 
715). This increase in rate of cure they attributed to some accelerating substance 
formed in the rubber by the action of micro-organisms, as they found that freezing the 
rubber inhibited the development of the rapid-curing properties, but these were 
restored on allowing the temperature to rise again. Further, formalin and other 
antiseptic treatment, ¢e.g., smoking, had also an inhibiting effect. They also observed 
that once the rapid-curing effect was produced, this was not destroyed by heating to 
relatively high temperatures, as in the treatment of the rubber in a hot-air drier or by 
washing on crépeing rolls. 
J. Grantuam (‘ Agric. Bull. F.M.S.’ 4, pp. 1-4) published a number of nitrogen 
determinations of plantation rubber and concludes that smoking appears to fix the 
nitrogen. Generally speaking, matured ‘slab’ gave low figures, especially after 
crépeing, in spite of the rapid-curing properties of this rubber. 
H. P. Srevens confirmed Eaton and Grantham’s results and succeeded in 
separating the accelerating substance, which wasfound to be an organic base or mixture 
of bases formed during putrefaction. The rapid-curing properties were found to be 
partly, but not completely, removed by washing on crépeing rollers, (‘ Journ. Soc. 
Chem. Ind.’ 1917, 36, p. 365.) Larger quantities of base could be extracted from 
rapidly-curing rubber than from slow-curing rubber. The bases can also be obtained 
from the latex serum and produce acceleration of vulcanisation when added to ordinary 
crépe. 
Synthetic organic accelerators.—A general description of organic accelerators for 
vulcanisation and their characteristics have appeared at various times (Ditmar, 
‘ Gummi Zeitung,’ 1915, 29, p. 425 ; Gottlob, ‘ Gummi Zeitung,’ 1916, 30, p. 303; A. H. 
King, ‘India Rubber Journ.’ 1916, 52, p. 440; 8. J. Peachey, ‘I.R.J.’ 1916, 52, 
p. 603; S. J. Peachey, ‘Journ. Soc. Chem. Ind.’ 1917, 36, p. 424). The first patent of 
importanceis givenas that of Bayer & Co., Elberfeld Farbenfabrik, Ger. Pat. 265,221 of 
Noy. 16, 1912. This was for the use of piperidene. Subsequently it was recognised 
that all organic bases act as accelerators, but that only those having a high dissociation 
constant are sufficiently powerful for technical work. Thisled to the patent taken out 
by Bayer & Co., claiming all organic bases having a dissociation constant greater 
than 1 x 10° (Ger. Pat. 280,198 of 1914). 8. J. Peachey has patented the nitroso- 
derivatives of certain bases (Eng. Pat. 4,263 of 1914), particularly p-nitroso-dimethyl 
aniline, which differ from compounds previously referred to in that they are not strong 
bases and are yet very effective accelerators. Peachey has also patented condensa- 
tion compounds formed by the interaction of aldehydes and amines (Eng. Pat. 7,370 of 
1914), but these substances are not so powerfulas thenitroso- derivatives. 
D. Spence (‘ Journ. Soc. Chem. Ind.’ 1917, 36, p. 118) claims to dispose of the 
novelty of all these inventions, and states that, six months previous to the date of 
application of the Bayer patent of 1912 (covering the use of piperidene), he described 
experiments in which piperidene was used in the ‘ Kolloid Zeitschrift,’ 1912, 10, 
pp. 303-305. 
Duntor Russer Co. and Twiss (Eng. Pat. 1916, 17,756) have patented the use 
of caustic soda or potash in solution in glycerol as a vulcanising accelerator. The 
accelerating effect of mineral bases is wellknown, particularly lime and magnesia. The 
glycerol is used as an agent for incorporating the alkali in the rubber (see also paper by 
D. F. Twiss (‘ Jour. Soc. Chem. Ind.’ 1917, 86, 782). 
Resinous constituent.—L. E. Weber, ‘The Action of Resins in the Vulcanising of 
Rubber’ (‘ Inter. Congress of Applied Chem.’ 1912, 9,95). The author prepared three 
compounds from the same mixing, containing rubber, litharge, sulphur, and whiting, as 
follows :—Compound A was prepared with plantation-smoked sheet, which had been cut 
up and extracted for fifteen hours with acetone. Compound B exactly resembled the 
foregoing except that the rubber was used without previous extraction. Compound 
C was identical with compound B except that it contained in addition the resins 
(acetone extract) obtained from the rubber used for compound A. On vuleanising (in 
water) it was found that compound A ‘ could not be vulcanised,’ that is to say, cured for 
one hour at 140°C. ; ‘if showed a strength of less than 201b.,’ while compounds B and 
C variously cured gave figures up to 800 lb. with irregular differences. The author 
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