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THE INDIA RUBBER ^VORLD 



[June i, 1906. 



RUBBER PLANTATIONS AND THHIR PRODUCT. 



THE NEW RUBBER AS VIEWED IN EUROPE. 

 ^Y^IIIv j^overnment rubber expert of the Federated Malaj- 

 I States, Mr. P. J. Burgess, m. a., v. c. S., has coni- 



-^ pleted his report on a visit of six months to Great 

 Britain, to investigate the India rubber industry in 

 its relation to the growth and preparation of raw rubber in 

 the Malay peninsula. Being well introduced, he appears to 

 have had no difficulty in gaining access to leading manufac- 

 turers and learning the details of manufacture, and also the 

 views of the trade in regard to plantation rubber. 



He states that he met uniformity of opinion among those 

 who had practically made trial of Straits and Ceylon rubbers. 

 All were agreed that the rubber was good and very service- 

 able, but by no means as good as South American fine Para, 

 either hard or soft cured. The plantation rubber is lacking 

 in "nerve", it works soft between the masticating rollers, 

 and its keeping qualities are inferior to South American 

 Para. After vulcanization the tensile strength is less and 

 the elastic recovery of shape after deformation by stretching 

 or compression is less perfect than shown by South Ameri- 

 can Para under precisely similar conditions. 



In several cases, notably at Silvertown, where accurate 

 tests of all rubbers u.sed are carried out, the recorded figures 

 showed an inferiority of S to 15 per cent., with differentsam- 

 ples of plantation as compared with native Para rubber. The 

 inferiority of the former was not confined to those physical 

 properties capable of immediate measurement, but was also 

 shown in the keeping qualities of the rubber. Samples of 

 plantation rubber two and three years old had all shown 

 marked deterioration, whereas samples of South American 

 Para of ages up to and over 40 years had preserved perfectly 

 their tough and elastic qualities. While this feature of 

 plantation rubber may have l>een due to errors committed in 

 preparation of 'the samples two or three years ago, it con- 

 firms practical users of rubber in their opinion that planta- 

 tion rubber is not reliable, and certainly not the equal of 

 South American Para. 



The cause of the inferiority of plantation rubber is not 

 known. Some manufacturers believe it to be due to differ- 

 ences in the locality, climate, and conditions under which 

 the trees have been grown ; others that is the result of dif- 

 ferent modes of curing and exporting, and again difference 

 in the age of the tree from which the rubber is gathered may 

 be the reason for difference in quality. Mr. Burgess makes 

 a further suggestion, which he believes has not before been 

 made. The rubber trees of South America which are tapped 

 are the finest and most sturdy in the forest— the result of 

 the survival of the fittest. Naturally only the best specimens 

 become mature, and the native in tapping selects the best of 

 the trees he conveniently can. On the plantation all the 

 trees which survive the first planting are tapped on attain- 

 ing suflicient size. 



Mr. Burgess proposes to endeavor to ascertain by tapping 

 selected trees on the plantations whether the rubber ex- 

 tracted is of finer quality than that of the average rubber on 

 the same ground. To make his test more thorough he has 

 had made in Manchester machines for practically working up 

 and vulcanizing rubber, with which to make test pieces of 



vulcanized rubber from the product of trees grown in vari- 

 ous localities, of difierent age, and cured in iliflferent ways, 

 making likewise jihysical tests of such rubber, and of sam- 

 ples of South American Para. 



Mr. Burgess does not feel in a position to say how rubber 

 should best be coagulated and prepared for export, but is in- 

 clined to recommend that as little as possible in the way of 

 acids be added to the latex. Where a washing machine is used 

 the milk might, he thinks, be allowed to coagulate by simply 

 standing 24 or 36 hours. Manufacturers .seem to object to the 

 use of any acid during rubber coagulation for fear that traces 

 of it might be left in the rubber even after washing. Whether 

 the objection to the use of a volatile acid in coagulating rub- 

 ber is really sound can only be decided by practical tests, but 

 the objection does exist. But to avoid using any coagulant 

 it is only practically possible where a mechanical treatment 

 of the rubber by a washing machine is in use, and then it is 

 a matter for consideration whether the use of acid, which has 

 been extremely convenient in assisting coagulation, should 

 be discontinued from fear that such use will produce a rubber 

 that will not stand the test of time and which will perhaps 

 injure in future the reputation of plantation rubber. 



Before the introduction of the washing machine and the 

 formation of crepe rubber, drying had been a troublesome 

 operation. Artificial heat had generally led to the softening 

 of the rubber and often, through inefficient control of the tem- 

 perature, caused it to become "tacky." Crepe rubber dries 

 easily and well if hung in a dark but airy shed, and the prep- 

 aration of rubber in this form appeared to have solved the 

 old difliculties in drying. 



There have been suggestions in regard to vacuum drying 

 on estates, and Mr. Burgess investigated the vacuum drying 

 of washed rubber in certain British factories. He reports 

 that rubber dried in this way is .softened by the heating, 

 which is objected to bj- some manufacturers, though by those 

 who have adopted vacuum drying this is not regarded as im- 

 portant, chiefly because the cause of softening is known and 

 it is regarded only as preliminary to the softening which oc- 

 curs in the mastication which is the next step in rubber 

 manufacture. But if plantation rubber were offered in soft 

 and adhesive masses Mr. Burgess feels that serious objection 

 would naturally be made. Taking into consideration the 

 fact that plantation rubber is always inclined to be soft he 

 would not recommend any form of drying in which artificial 

 heat is necessary, and which involved the elaboration of 

 machinery and increase in power in doing what, with washed 

 rubber, can be done in a more simple, safe, and natural man- 

 ner. 



By all the manufacturers seen in Phirope a lively interest 

 was shown in plantation rubber and in the prospect of be- 

 ing able to obtain rubber of fine quality from the East. The 

 immediate need is more quantity, and exaggerated views 

 prevail of the amount to be expected in the near future from 

 plantations. Manufacturers were not inclined to deal direct- 

 ly with the producer in small lots, the supply being too 

 small and irregular to ju.stify a departure from existing 

 methods of buying, besides which plantation rubber requires 

 different treatment in working. Unfortunately some of the 



