Show BUSINESS ASPECT OF SYNTHETIC RUBBER at the general jubilee meeting of the society german chemists which took place at Freid freidberg burg in wt last whitsuntide the attention fort ol of the general public was drawn to the question of the synthetic production of india rubber two workers of special prominence in this field prof C I 1 li harries arries of kiel and dr F hofmann of elberfeld Elb erteld giving a comprehensive deport je ite port from roin the scientific and technical standpoint on the present status of the problem only recently prof Per perelia plia in england has hag read a paper on the same came subject and has given publicity to now new results of research in this field while however ho Never tile tae two german investigators vesti gators mentioned above were very guarded and skeptical in their espres blons biona relating to the future of synthetic and regarded the time when synthetic rubber will appear upon the market as still far off the lecture of the english chemist was more optimistic tile the result was that a company with was immediately founded which counts among its board of directors no less a chemical authority than sir william ramsay while sir william alden has been retained as consulting chemist nevertheless erth eless the opening of the list for subscriptions for shares so far as we can judge from report seems to have been a comparative failure only a i a very small amount of capital having been sunk stink in the new foundation the conservatism displaced in thi ahli 3 I 1 case by the engl english ish public would seem to be entirely justified tor for upon crit lical examination it it Is found that even the new results communicated by prof perkin do not by auy any means justify the hope that any considerable quantities of sn synthetic will be b produced in the near future from the scientific standpoint the question of synthesis is clear at the present time atas it is well known that is formed from isoprene a compound of carbon and hydrogen obtained as a mobile colorless liquid ot of low boiling point 3 35 5 des deg cent lor for example on heating itself or turpentine As i was as first shown by II rubber like b bodies 1 d I 1 m ar are also obtainable from other c compounds arsi P of carbon and hydrogen be bides aides isoprene which however must have a somewhat similar chemical constitution among them may be the transformation of such compounds compon into can be effected either cither by simply heating under tinder pressure with or without the addition of other substances I II lofman or by the influence of small quantities of metallic sodium harries the products obtained differ entirely ill iii their properties according to the natcie of the initial material L employed and the conditions condi tons of transformation in order that synthetic rubber may be capable of 0 competing successfully with the natural product it must be equal to it in technical use and must be at least as cheap to ma manufacture nu facture As regains the first question there can hardly be any doubt that in the course of time it will be possible to produce rubber by artificial means which be equal or even superior to natural lubber in technical us use e we have not as yet arrived at this stage the price of synthetic rubber on tho the other hand depends in fit the first placer place on the cost of production of the initial material material isoprene and allied hydrocarbons here flere also it can hardly be doubted that before very long processes nill ill bo be found which will yield these substances more cheaply than methods knon hitherto at the present time ho boeer eer there is no such method known for isoprene the parent sub stance of natural rubber robber the problem is rendered particularly difficult through the tact fact that the substances employed must be specially pure most of the processes proposed hitherto do not yield a pure isoprene bue bin mixtures of different hydrocarbons of similar constitution fl hofman himself in the preparation of f pure isoprene starts from a constituent of coal tar namely cresol but in this process also so far as can be judged at the present the cost of production is considerably sider ably greater than for natural rubber but een if it should be possible to prepare sufficient quantities of oc iso so rrene at a sufficiently low cost the difficulties of 0 tle the poblet rs ns I 1 qs is pointed out elly begin beo ii for me ysido are comparatively sn ill all in ii methods of ahn his ard co equen lly in technical production on a large scale such as is implied in ill case wi sd ious fous competition with the natural product ro should be contemplated such en e ormus oratus quantities of by products are obtained that their disposal or utilization would probably present a more difficult problem from the economical and technical point of view than manufacture ot of the itself how is it in this regard with the new mew pio cess communicated by prof 11 hofman and so hastily made the basis of financial operations the principle or of the new method or of producing sy synthetic i depend on the one hand on the cheap production of hydrocarbons which can be as initial materials for rubber on oil the other hand on the acceleration of the conversion of these hydrocarbons into rubber like substances prof fernback of oc the institute in paris has haa shown shown that starch obtained from potatoes or matzo maize can be converted by means of yest like ferments into a mixture of fusel oil and acetone front from these compounds the hydrocarbons required as raw material tor for the can be produced by suitable chemical transformation the transformation of these substances into rubber like bodies is effected by means of metallic sodium that is to say by the sa same me means as discovered and used independently by harries according to perkins ns communication this method was discovered and made the subject of patent application by matthews halt a year before harries though no publication li was made of the fact it must therefore be admitted that the prior priority of invention belongs to matthews the use ot of starch as the initial mat enal is alluring at first sight owing to its low prie price when lio however wever we examine the new process a little more closely we cannot quite suppress doubts as to its financial soundness an ali inquiry addressed to the highly refuted india rubber hubber journal of london regarding yields obtained in the several stages of the process brov bjorg at al ilie hie following information by process there is obtained irom from starch 42 per cent to 43 per cent crude fusel fusei oil the starch content of potatoes potatoe s or maize is about 60 per cent the fusel 1 oil itself is said to contain contain only about two thirds of true fusel oil the rest being behig acetone and other compounds furthermore the fusel oil gives a yield of 40 to 50 per cent of isoprene which latter is converted w without I 1 phout 1 loss os 8 into rubber according to calculations which the above men tinned english technical journal made tons of starch will be required tor for the production of i 1 ton toil of synthetic in this way from this it follows that only about 1 per cent yield figured on oil the starch is finally obtained while 99 per cent of the latter goes into by products for the production of a quantity of synthetic rubber corresponding to tile the present worlds consumption about tons such an immense surf surface ace would have to be planted with potatoes that the ground now occupied by rubber plantations would represent only a 1 small fraction of this that such a process as this cannot be very practicable is obvious added to this is the tact fact that the proof is still owing that the material obtained by the english process fulfills the beell conditions As has been shown by harries artificial rubbers obtained by means of metallic sodium differ chemically from natural rubber it is therefore not by any means probable that the new fi products will be found equal jn in their mechanical and physical properties to natural rubber tile the situation is rendered still more difficult through the fact that the chief constituent of the product obtained by Fern bachs process is so called butyl alcohol which on oil further treatment does not yield isoprene that the parent substance of natural but which has already been referred to we may therefore expect that the Engli english sli process will yield substances differing materially in their properties from natural rubber in any case their technical usefulness and value is still awaiting proof ou on this point there is practically no evidence available tho the invent invention ionis is still in fit the laboratory stage As wo we read in the india rubber journal there have hitherto not been prepared more than one or two pounds of synthetic rubber by the newly described process there is therefore no doubt that the formation of the company is premature synthetic rubber ly come aud and will claim its place upon the worlds market not suddenly however e er at one blow but gradually even then it is much more likely that some sort of equilibrium will be struck similar to that which now exists with nith regard the artificial and natural silk in the field of technical progress the law of inertia rules is as in other domains scientific american |