584 



THE INDIA RUBBER WORLD 



[July 1, 1917. 



6. Cutting out the test piece, scribing, gaging, testing 

 for strength, calculating results: total for live test 

 pieces cut from one slab 30 



Total time consumed for entire test and report 360 



XoTE 1. The optimum cure for this particular compound 

 was found to be: 30 minutes at 50 pounds steam pressure 

 (= 297 degrees F. = 147 degrees C.)- All specimens were 

 allowed to rest 210 minutes after vulcanization, before testing 

 for strength, but it was found that specimens which had rested 

 24 hours after vulcanization showed a very slight increase in 

 strength. 



XoTE 2. The tests were carried out on Fine Para rubber, 

 Hevea Ribbed Smoked Sheets, and Hez'ea First Latex Gristly 

 crepe. 



Note 3. The rubber compound was vulcanized in a steam 

 press in the form of a sheet not greater than Ys inch in thick- 

 ness. The test specimen was cut from this sheet by means of a 

 die, not less than 0.25 inch wide at the constricted part. (See 

 "The Journal of Industrial and Engineering Chemistry," 1912, 

 page 452). 



Note 4. Batches weighing 500 grams each were prepared 

 according to the following recipe : 



Per Cent. 



Rubber 50 



Zinc oxide ■ 37 



Litharge 10 



Sulphur 3 



Total 100 



(A) With Fine Para Rubber: 



Experiment No. 1. Vulcanize for 30 minutes at 50 pounds. 

 Allow specimen to rest three hours after vulcanization. Ten- 

 sile strength, 3,053 pounds ; elongation, 2 to 14.4 inches. 



Experiment No. 2. Vulcanize for 40 minutes at 50 pounds. 

 Tensile strength, 2,928 pounds ; elongation, 2 to 13.9 inches. 



(B) With Hevea Ribbed Smoked Sheets: 



Experiment No. 3. Vulcanize for 30 minutes at 50 pounds. 

 Tensile strength, 3,167 pounds; elongation, 2 to 14.1 inches. 



Experiment No. 4. Vulcanize for 40 minutes at 50 pounds. 

 Tensile strength, 2,935 pounds; elongation, 2 to 13.6 inches. 



(C) With Hevea First Latex Gristly Crepe: 



Experiment No. 5. Vulcanize for 30 minutes at SO pounds. 

 Tensile strength, 2,827 pounds; elongation, 2 to 14.0 inches. 



Experiment No. 6. Vulcanize for 40 minutes at 50 pounds. 

 Tensile strength, 2,533 pounds ; elongation, 2 to 13.4 inches. 



The "Factor of Elongation" is the term applied to the quotient 

 obtained by dividing the original length into the ultimate 

 length. If a specimen stretches from 2 to 14.4 inches, the factor 

 of elongation is 7.2. 



FALL MEETING OF THE RUBBER SECTION OF 

 THE AMERICAN CHEMICAL SOCIETY. 



GULF SULPHUR OUTPUT INCREASING. 



In order to meet the increasing demand for sulphur and its 

 products, the output of the great mines in Te.xas and Louisiana is 

 being greatly increased. The Freeport Chemical Co., Freeport, 

 Texas, a subsidiary of the Stauffer Chemical Co., San Francisco, 

 California, has placed in operation the first unit of a new plant 

 for the manufacture of sulphuric acid and other products which, 

 when completed, will represent an investment of about $450,000. 

 The mines are situated near the mouth of the Brazos River and 

 it is proposed at a cost of $455,000 to deepen the present 18-foot 

 channel to 25 feet so as to accommodate larger vessels to meet 

 the shipping demand. 



Last year the United States used approximately 900,000 tons 

 of sulphur, three times the annual consumption before the war. 

 It is estimated that the 1917 demand will be 1,200,000 tons and 

 that 1,600,000 tons will be the annual reipiirement if the war 

 continues. 



[Dr. Tullle's appeal to make tlie chemical symposium and 

 program of papers at the forthcoming meeting even more prac- 

 tical and constructive than last year is so well stated and covers 

 the ground so thoroughly that his announcement is published in 

 full. During this great }tational crisis, when trade, commercial 

 atvd professional conventions for the exchange of ideas regarding 

 efficiency are far m,ore necessary than in times of peace, all 

 rubber chemists should make an e.rtra effort to tend a full meas- 

 ure of cooperation. — Editor.'\ 



THE Fall meeting of the American Chemical Society will be 

 held in Boston during the week of September 10 to 16, 1917. 

 The Rubber Section will hold its session at that time, and while 

 the date has not been decided upon, it will probably be on Wed- 

 nesday, Thursday, or Friday, September 12, 13 or 14. 



I am particularly anxious to get the program arranged as 

 soon as possible, so as to permit its wide distribution in plenty 

 of time before the meeting so that members may easily arrange 

 to be present. I wish, therefore, that all those who expect to 

 present papers to the meeting will send me the titles at the earliest 

 moment. We are going to try a new stunt this year : we want 

 abstracts of all papers to be in the hands of the secretary at 

 least a week before the meeting. These will be mimeographed, 

 and placed in the hands of those present at the meeting. We 

 expect this to stimulate discussion and bring out valuable and 

 helpful criticisms. The success of the symposium of last year has 

 encouraged us to repeat the idea again this year. The following 

 subjects have been proposed: 



1. Determination of total sulphur. 



2. Determination of rubber. 



3. Organic accelerators. 



4. Crude rubber resources of the United States. 



Those who care to prepare a short talk on one of these sub- 

 jects, preferably covering their own experience, should so notify 

 the secretary. This need not be a formal paper on the subject, 

 but of course should be the result of careful study. We are also 

 open to suggestions as to other topics which might be of interest. 



At our meeting last year, there were present over one hun- 

 dred members and guests. A glance at the proceedings as re- 

 ported in The Indi.\ Rubber World in October, November and 

 December, 1916, will give you some idea of the value of the 

 meeting. Whether or not this year's meeting will prove equally 

 profitable will depend largely upon the support which the meet- 

 ing will receive from the rubber chemists. No better oppor- 

 tunity than this is offered to meet your fellow chemists from all 

 over the country and discuss such problems as do not involve 

 trade secrets, the solution of which would be of considerable 

 value in your laboratory. This phase of the Rubber Section's 

 activities would in itself justify- its existence. 



Some time during the next two weeks I wish every member 

 of the Section would take time to write me a letter giving at 

 least one suggestion as to how to run this next meeting. I 

 know that if some of the suggestions given to me after the 

 meeting last year had been received a few weeks earlier, we 

 would have had a better meeting. 



All those who were not present at tlie last meeting, and who 

 are interested in receiving advance notices of the program, etc., 

 should send their names in at once, so that they may be placed 

 on the mailing list. 



The following will be of interest as showing the geographical 

 distribution of those who registered at the 1916 meeting. In 

 addition, there were about 15 or 20 who failed to register. New 

 York City 22, New York State 9, Massachusetts 16, New Jer- 

 sey 15, Pennsylvania 12, Ohio 11, Rhode Island 3, Connecticut 

 4, Western Stales and Canada 10. 



John B. Tuttle, Secretary. 



Address : Bureau of Standards, Washington, D. C. 



