Melting Point of Rosin. - ACS Publications - American Chemical Society

Properly speaking, rosin, like asphalt, has no definite melting point, therefore, any specification aiming to grade it by reference to its behavior on...
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T H E JOURNAL OF INDUSTRIAL A N D ENGINEERING CHEMISTRY

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beads or rods are used, yet absorption is as rapid as with either. These pipettes may be made by any good glass blower, or they may be obtained for about $ j . o o each from Mr. Paul Anders, Urbana, Illinois. COLLEGE O F AGRICULTURE os ILLINOIS UNIVERSITY URBANA,ILLINOIS

NEW REFLUX CONDENSER By JAMESJ. BAJDA Received July 10, 1918

A modified type of reflux condenser, applicable t o most kinds of laboratory work, has been found very satisfactory, especially in those cases in which t h e refluxing liquid has a comparatively high boiling point. I n t h e usual type of reflux condenser, hot vapors enter the relatively cold portion of the cooling chamber and allow the condensed liquid t o collect in t h e inner tube, until overbalancing pressures therein cause t h e liquid t o spurt back into t h e receiver. This spurting back is often not very desirable, especially as the receivers are usually made of glass. The improvement here is obvious from the accompanying drawing and consists of a vapor conduit, 2 , forming a part of t h e adapter of the condenser I , through which t h e vapors pass and are led therefrom into the upper part of the condensing coil 3. The condensate flows into the t r a p 4, b y means of which is provided regular and undisturbed flow into the receiver. Any tendency t o disturb t h e balanced relation of the condensed liquid in t h e t r a p will find outlet through one arm of t h e Y-tube which leads upwardly and axially, 5, through t h e cooling coil 6. The flow of c o o h g water in a direction opposite t o t h a t of t h e condensates diminishes the strain on t h e glass.

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FLUSHING, I,. I. N E W YORK

Vol.

11,

No.

I

MELTING POINT OF ROSIN BY T. LINSEY CROSSLEY Received August 2, 1918

Certain large buyers of rosin have recently specified a melting point limit for this material. Samples have been submitted for this test, b u t without specifying how t h e test was t o be carried out. Properly speaking, rosin, like asphalt, has no definite melting point, therefore, any specification aiming t o grade it by reference t o its behavior on heating should state t h e method for obtaining results. Schwalbe and Kuderlingl not only state melting points but record results t o fractions of one degree and claim t o differentiate between certain rosins b y their melting points. Several methods have been used t o determine t h e quality of rosin as indicated b y its action on heating. The closed capillary tube, of such general application, is used largely but, unless conditions of heating and observation are closely controlled, results are not uniform with different operators. The following results were obtained on t h e same four samples b y methods indicated: Rosin 1..

..........

2

............

3

............

4......

......

1/4 in. Column F. 174-184 172-183

l/s in. Column

F.

176-187 174-185

169-172 169-172 165-173 174-182 167-176

161-167 161-157

149-15 1 145-146

...

...

...

.

.

I

...

153-155 145-147 147-155 144-145 149- 153 Heated until clear. Probably mechanical weakness of film.

...

(a

(b]

Film

F.

150 146

...

147 155 156 120(b) 134 126 135 133

...

Capillary F. 146 145 154(a) 154 147 153 128 130

...

138 136

...

The first three methods were carried out as follows: Glass tubes of about S/le in. inside diameter and 2 in. long were prepared. These were dipped in melted rosin so t h a t on cooling there was left inside t h e t u b e a column of rosin of the required depth. I n t h e case of t h e method marked “Film” t h e foot of t h e glass tube was heated slightly and applied carefully t o t h e surface of t h e molten rosin so t h a t upon cooling a thin film only of t h e rosin was formed. The tubes were attached to the thermometer in such a way t h a t t h e bottom of t h e tube with t h e rosin was located about t h e center of t h e mercury bulb. The thermometer with tube attached was immersed in cold water in a 400 cc. beaker with t h e bottom of t h e rosin column I in. below t h e surface. The temperature was raised about 3’ per minute. I n t h e cases of 1/4 in. and in. columns, it will be noted t h a t two temperatures are given. The lower temperature indicates t h e point a t which the rosin is soft enough for t h e water t o enter t h e tube, t h e other being the point a t which t h e water breaks through. The result is of course merely t h e point a t which t h e viscosity is so reduced t h a t it is overcome b y t h e pressure of I in. of water. It is necessary t h a t t h e heating should be well regulated. If heat is applied too rapidly it will naturally result in a higher final temperature and a wider spread between t h e two points. 1

“Rosin Studies,” J. SOC.Chem. Ind., SO, 1397.

Jan* )

19 I 9

T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING CHEikISTRY

T h e capillary tube method was carried out as follows: Tubes about I mm. in diameter were p r e p a r e d and sealed a t o n e e n d . T h e rosin was pulverized bet w e e n two pieces of paper. A b o u t 2 cm. of t h e t u b e were filled with t h e powder, and i t was a t t a c h e d t o t h e t h e r m o m e t e r as i n t h e o t h e r cases, being also immersed in cold water a n d h e a t e d as before. A reading glass was used t o observe t h e result and the p o i n t at which t h e particles coalesced was noted as the melting point. I t was not f o u n d advisable t o carry the heating u n t i l the whole of t h e rosin in t h e t u b e became clear as t h i s increased t h e r a n g e of personal error. T h e r e was found t o be a more definite

I-

indication and closer a g r e e m e n t when t h e p o i n t of coalescence was noted. T h e results o b t a i n e d by t h e “ F i l m ” m e t h o d are for practical purposes t h e s a m e as t h o s e o b t a i n e d b y t h e “Capillary” m e t h o d , b u t the tests a r e p r e p a r e d more r a p i d l y a n d with m u c h less trouble, especially in the h a n d s of unskilled assistants. T h e end-point is definitely established b y t h e p e n e t r a t i o n of t h e water. I n all of these tests recently boiled water should be used, otherwise t h e rising bubbles of dissolved gases interfere in several ways. 43 SCOTT STREET ONTARIO TORONTO,

ADDRESSES

THE FUTURE OF THE AMERICAN DYE INDUSTRY1 B y W. H. N I C H O L S , President, American Chemical Society

When war was forced upon the world in 1914, the chemical industry of England, France, Russia, and Italy was quite unprepared for the tremendous demands made upon it, some of t h e most insistent being for materials hitherto unmade in any .of those countries, due to the shrewd policy pursued by the Germans for many years in anticipation of the event. The chemical industry of the United States was in far better state of preparation and, as is well known, was able to fill the gaps. On our own entry into the war, it appeared to those in authority a t Washington that large additions should be made to the chemical output. To accomplish this result, our Government thought best to construct largely, and to assist certain individuals and corporations in doing likewise. As the chemical industry was thoroughly prepared to take care of the requirements of our own country before the war, it is fair to assume that it is in position to do so when we return to lines of peace. It is therefore manifest that a number of works in which the Government is interested will not be needed, and it is hoped that the manufacturers who so bravely and liberally contributed to the increase in output, will not now find themselves in competition with governmental plants. While I am informed the Government will take careful account of this, and will do what it can to protect industry already organized when the war began, I believe the potential injury should be alluded to in order that the large gathering of manufacturers here might be in position to express itself should it so desire. The fortunes of the chemical industry are naturally bound up with the fortunes of industry a t large, and the same rules which apply to any other industry would apply in almost every case to the chemical. If the country returns to its pre-war state of manufacturing capacity, the chemical industry will be able t o take care of itself and any demands that are made upon it. Therefore, its future will be identical with the future of all the great undertakings with which we are involved. I have not thought it best to take up your time with discussing general details, knowing that these will be considered in the brdinary course of events. I have thought that with the limited time accorded me, I might be of some service in calling specific attention to an industry which is practically new in this country, which is vital, and which absolutely needs encouragement; in fact, all the encouragement which can be forthcoming from every source. I refer to the manufacture of coal-tar dyes and medicinal preparations which up to 1914 were produced almost exclusively either in whole or in part by the great German concerns. Owing 1 Address t o the Chamber of Commerce of the United States, Atlantic City, Deccamber 6, 1918.

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to the fact that for nearly forty years these concerns had earned and obtained d practical monopoly of the whole world, they were able to charge prices which made it possible to write off all or the greater part of their plants, so that to-day they are in the position of having plants, doubtless largely increased by war orders, which stand on the books a t comparatively small sums. I n addition to this, they have the further advantage of having works which are perfected to date, whereas other countries have had to invest in plant, and will still have to do so, with the certainty that much of its construction may be scrapped as knowledge advances. With a full appreciation of these difficulties, manufacturers of England, France, and Japan have received the strongest kind of encouragement from government cooperation, financial and otherwise, and Switzerland permits by its laws the combination of the chief color works, three in number, in such way that processes and patents may be pooled For the common good. In Germany, as is well known, a union of all the great color works has been effected, binding for fifty years, and while the various units composing the same do not lose their identity, or control over their works, etc., still their activities will be controlled by their ability to produce stated products a t minimum costs. Profits will be pooled and divided as already agreed; losses likewise. These various facts leave the United States as practically the only great country this side of China frankly open to the German assault, which is sure t o come and which should be nipped in the bud. Our present protective tariff is entirely inadequate. I understand that plans have been completed to ship goods already prepared in immense quantities from Sweden, Holland, Switzerland, etc., so that their German origin will be carefully camouflaged. Of the several branches of chemical industry, a t the outbreak of the war, none bulked so large in the eye of the public as the coal-tar dyes and none so gripped public attention. The reason is now not difficult to determine. While the coal-tar dye and its directly related industries do not occupy a leading rank in the world’s activities when measured by the customary and usual standards, such as those of labor employed, capital engaged, value of output, tonnage of output, power consumption, and the like, yet their products did perform almost, if not wholly, indispensable functions in very varied industrial operations of exceeding magnitude, importance, and ramification. It is this functional value, rather than any intrinsic direct money value, that now determines the importance in which the public holds these products. Out of this new viewpoint as applied to coaltar dyes has grown an entirely new public conception of utility which the public has embodied in the now widely-current expression of “key” or “pivotal” industries by which emphasis is very decidedly placed upon functional importance, and other considerations are deliberately relegated far to the background.