212 



THE INDIA RUBBER WORLD 



[February, 1, 1912. 



especially to the Straits Settlements, where it developed to an 

 exceedingly flourishing plantation tree. Since this tree furnishes 

 a highly valuable product in Brazil it rriust, necessarily, give the 

 same product in its new habitation, provided that the coagulation 

 takes place under the same conditions. Owing to the enormous 

 size of modern plantations it was, however, absolutely impos- 

 sible to introduce the manual extraction of Para rubber in the 

 Straits. Therefore such methods of coagulation were adopted 

 as would make it possible to extract the rubber by machinery, 

 but by means of which an equally valuable product can never be 

 gained. First of all acetic acid was found to be an agent 

 which permitted an easy mechanical extraction of a product 

 which, however, had great defects. The most serious defects are 

 the following ones, viz.: 



1. The coagulation with acetic acid takes too much time. Ac- 

 cording to the doses which are added to the latex its coagulation 

 requires several hours, and in many cases even a whole day. If 

 a quick coagulation is to be obtained, very large quantities of 

 acetic acid must be employed. Now as regards the rubber 

 produced with the aid of acetic acid it becomes gelatinous dur- 

 ing the coagulation process, which is to be attributed to the 

 fact that the rubber molecules do not receive sufficient poly- 

 merization. 



2. Acetic acid also does not prevent the rubber thus obtained 

 from getting mouldy very quickly, owing to the damp hot air in 

 the tropics. 



3. The rubber has no elasticity (nerve), and in consequence is 

 inferior. 



4. A very serious drawback of coagulation with acetic acid is 

 that tiie metallic salts, which are of so great importance for 

 the vulcanization, are precipitated as acetic salts. Now, these 

 acetic salts make the rubber soft later on when it is to be used. 



5. If acetic acid is used in quantities, small crystals like sand 

 are developed in the rubber, and these crystals are precisely the 

 injurious acetous compositions of the otherwise valuable metallic 

 salts of the rubber. 



6. The rubber coagulated with acetic acid- has ^ut a very in- 

 ferior viscosity, which is the best proof that the polymerization 

 of thev.cub^er is the worst imaginable. 



7. Further, the subsequent vulcanization does not furnish the 

 valuable product of the Para rubber. From the very beginning 

 the rubber is lacking in elasticity (nerve). If up fo the present 

 plantation rubber coagulated with acetic acid has' been able to 

 letch about the same high price as Para, this result can not be 

 attributed to the excellent quality of the Hevea plantation rubber, 

 but solely to the fact that the rubber is put on the riiarket in 

 a clean and dry state without any loss in washing. If the values 

 of Para rubber and Hevea rubber are to be compared it must 

 be taken into consideration that Para has 18 to 20 per cent, loss 

 in washing (locked up serum), while plantation rubber does not 

 sustain any loss in washing. 



If they had continued to proceed with the extraction of plan- 

 tation rubber in this direction (although the attempt has been 

 made to change it by having recourse to all kinds of coagulation 

 methods, which, however, consisted always in strong acids) then 

 plantation Hevea rubber would constantly have remained in the 

 background. 



■'All this has been changed at one blow by the important dis- 

 covery of carbonic acid as coagulation agent of the latex. For 

 the whole plantation industry this discovery is the most im- 

 portant made in decades. The most remarkable part of it is the 

 discovery that carbonic acid alone is the efficacious agent which 

 conferred on the Para rubber its past superiority. This discovery 

 is very important, because plantation rubber in future produced 

 in the simplest way imaginable by machinery is thereby so much 

 improved that it far surpasses the wild Para rubber in quality, 

 (nirity and strength. In order to distinguish this new rubber 

 from Para rubber and the plantation Hevea rubber hitherto ob- 



tained by strong acids, it shall be called "Hevea Para," which 

 name it well deserves. The valuable quahities realized by the 

 use of carbonic acid are the following: 



1. Carbonic acid coagulates the latex instantly. The latex is 

 an emulsion of fluid rubber particles in conjunction with vege- 

 table albumen. The reaction of carbonic acid on these albuminous 

 vegetable substances is so vehement and efficacious that as a 

 result the different rubber particles unite suddenly with the great- 

 est vehemence, which bestows on the rubber obtained an exceed- 

 ingly strong polymerization. The Hevea rubber thus produced 

 possesses all the valuable qualities of Para rubber. 



2. The "Nerve," tensile strength and elasticity are superior to 

 the same qualities in Para rubber. 



3. One of the chief advantages of ''Hevea Para" lies in the 

 fact that the valuable metallic salts of the latex are contained in 

 the rubber as carbonates, just as with Para, for they had been 

 precipitated by aid of carbonic acid. 



4. "Hevea Para" also is alkaline, for carbonic acid, as is well 

 known, does not disturb the alkaline qualities. 



5. "Hevea Para" possesses the same viscosity and yielding 

 (|uality of the solution, and vulcanized furnishes the same valu- 

 aljle product as Para. 



6. Coagulation by carbonic acid is the cleanest process and 

 gives the purest and lightest product. 



7. The smoke, however, mixes many coal-particles with the 

 Para rubber. 



8. "Hevea Para" never becomes mouldy, because the acid 

 precipitates the vegetable albumen contained in the latex, and 

 thereby destroys the whole fostering soil for these bacteria. 



9. "Hevea Para," just like Para, can neither decay nor oxi- 

 dize. 



10. The rubber coagulated with acetic acid is quickly covered 

 with a bluish colored coating. This is due to the fact that the 

 albumen still contained in the rubber in spite of the acetic acid, 

 decomposes rapidly under the influence of light and climate, 

 partly forming phenols at the same time. The phenols give the 

 bluish color to the rubber and depreciate it to second quality. 



11. Carbonic acid renders it feasible for the first time to em- 

 ploy just as for Para, a gas for the coagulation instead of strong 

 acids. 



12. The employment of carbonic acid is exceedingly simple and 

 may be entrusted to anybody. No exact weights have to be fixed, 

 as in the case of acetic acid and all strong acids; each native 

 may use as much carbonic acid as he likes. He never can do 

 any harm to the product, the surplus of carbonic acid escaping 

 as superfluous and inoft'ensive gas as soon as the spontaneous 

 coagulation is finished. 



13. Also the cheapest agent imaginable has been discovered in 

 carbonic acid. The remarkable progress as regards the produc- 

 tion and transport, enable the rubber plantations to procure 

 for themselves a good, valuable and cheap coagulation agent. 



It is possible to produce 2 kilos of carbonic acid with 1 kilo 

 of coal, whence the cheapness of carbonic acid follows. 

 ■ 14. Carbonic acid can be procured in all tropical countries be- 

 cause artificial carbonic waters are consumed there in almost 

 every small town. 



This new carbonic acid process has been patented in all coun- 

 tries, as it is of eminent importance for the whole plantation in- 

 dustry and for the whole rubber world, because at one blow it 

 ensures the victory over Para rubber to the Hevea rubber. 

 Owing to the patent having been registered, every forbidden 

 utilization, of course, will be punished by law, and every "Hevea 

 Para" produced illegally without license will be confiscated on 

 the strength of the patent law. It is very easy to ascertain by an 

 analysis whether rublier has been produKil witli the .ltd of the 

 new process or not. . 



