564 



THE INDIA RUBBER WORLD 



May 1, 1921 



the animal oiU, the oil of menhaden fish, and the oil of hogs 

 known in commerce as lard oil. 



GROUP 3 



The Dryinx Oils have been recognized for many years as 

 important constituents of paints, varnishes and plastic masses. 

 They are also used in the manufacture of oilcloth, linoleum and 

 sulphurized oil products. This group includes linseed oil pro- 

 duced in the United States; the tung oil or China nut oil of 

 China and Japan, the perilla oil of East India and China. 



Sulphurized Oils (black rubber substitute, black oil substi- 

 tute) can be made by heating the oil of peanut, soya, corn, cotton, 

 rape, linseed or menhaden with flowers of sulphur until chemical 

 combination has taken place. These products will always be found 

 to contain a high percentage of free sulphur and free oil. 



Chlorin.\ted Oils (white rubber substitute) are prepared by 

 the action of the liquid sulphur chloride on these oils. If desired 

 the oil may first be thinned down with an equal volume of some 

 suitable volatile solvent, and the sulphur chloride may then be 

 added to this mixture. A third method consists in spraying the 

 oil into a chamber containing vapors of sulphur chloride. 



GROUP 4 



COTTOX-SEED Ste.\rix is practically the only plant fat occuring 

 in the United States. This is the solid matter which settles out 

 when cotton seed oil is chilled. 



Palm Fat is obtained from Africa and the Philippines. 



Coconut Fat is obtained from China, Ceylon, Brazil and 

 Florida. 



Japan Fat, known in commerce as Japan wax, is obtained from 

 the berries or fruits of sumac trees in Japan and China. 



GROUP 5 



The Plant Waxes include carnauba obtained from Brazil and 

 other South .American countries as well as candelilla wax obtained 

 from Mexico and southern Texas. 



Wool W.\x, known in commerce as wool grease, is obtained 

 from high-grade wool by extraction with a volatile solvent, or 

 by scouring, while beeswax is the familiar product of the honey 

 bee. 



GROUP « 



The Resins available in large quantities vary in character from 

 the bitter-tasting colophony, which can be converted into water- 

 soluble sodium resinate, to the brittle resin of Pontianak or jelu- 

 tong which is practically unsaponifiable. 



Jelutong Resin. The resin e.xtracted from Pontianak (Dyera 

 costulata) by means of a mixture of acetone-gasoline possesses 

 characteristics of such commercial importance that they are 

 worthy of detailed notice. Washed and dried Pontianak yields 

 on an average 75 per cent of resin, the balance being a rubber. 

 The melting point of the resin is about 160 degrees C. (320 degrees 

 F.). Its molecular weight is between 372 and 392. Some have 

 considered the major constituent of jelutong resin to be an 

 alcohol of the cholesterol series, while others have found in 

 the resin certain bodies related to the sterols, namely, the acetates 

 of lupeol, of alpha-amyrin, and beta-amyrin. Iso-cholesterol (dex- 

 tro rotary) has also been recognized as present. It will be recalled 

 that an ester of this alcohol is contained in wool grease. Jelutong 

 resin so far as known is entirely unsaponifiable. This fact com- 

 bined with its high melting point has been the principal cause for 

 the use of Pontianak as an ingredient in "friction" compounds. 



GuAYULE Resin. This materia! is quite unlike the resins 

 obtained from other varieties of rubber. It is very sticky, almost 

 like molasses at a temperature of 60 degrees F. So far as known 

 it contains no stearol-Iike constituents. The washed and dried 

 guayule obtained from the Parlhenium argentatum of Mexico 

 contains about 25 per cent resins. They are, like the resins of 

 Pontianak, soluble in commercial acetone as well as in a mixture 

 of 53 gallons acetone and 47 gallons (of 70-degree) gasoline. 



Pine Resin. This is the solid residue found in the stills after 

 the volatile oil has been driven off in the purification of crude 

 turpentine. It is brittle, has a slightly bitter taste, with a 

 smooth, glassy fracture. Colophony forms about 66 per cent of 

 the crude turpentine. It is obtained from the long-leaf pine 

 (Piiius palustris) found in the Carolinas. When boiled with 

 caustic soda it takes up water to form a sodium salt of abietic 

 acid. One hundred pounds of resin can be saponified by boiling 

 with 15 pounds of soda ash. The melting point of pine resin is 

 130 degrees C. or 266 degrees F . 



GROUP 7 

 . The resinous gums include: natural guayule obtained from 

 Parthenium argentatum, containing about 20 to 25 per cent resins ; 

 balata obtained from Mimu'sops globosa, containing from 40 to 50 

 per cent resins ; gutta percha obtained from Palaquium gutta, 

 containing about SO per cent resins; chicle obtained from Achras 

 sapota, containing about 60 per cent resins ; jelutong obtained 

 from Dyera costulata, containing about 7S per cent resins. 



GROUP 8 



Rubber gums, strictly speaking, would include all those rubbers 

 of commerce containing not more than 5 per cent of resins based 

 on the washed and dried weight. Fine Para rubber, medium 

 Para rubber, coarse Para rubber ; plantation Hevea rubber, both 

 smoked sheets and crepe — all come easily within this group. 

 Ficus, Funtumia and Landolphia rubbers with a resin content 

 varying from 6 to 20 per cent would more properly be classed 

 with the resinous gums.' 



Part II — Plastic Masses 



It is an interesting fact and one not generally recognized, 

 that there are a number of industries which have many problems 

 in common, therefore chemists and engineers would do well to 

 examine into the processes, raw materials and products used in 

 industries outside of their own. 



The point is well illustrated in the case of concerns manu- 

 facturing rubber products, linoleum, oil-cloth, paints and 

 varnishes. These industries are grouped together because they 

 are based on the use of plastic masses. Generally speaking, they 

 utilize oils, fats, waxes, pitches, resins and rubbers on the one 

 hand and powdered minerals on the other. To be more definite 

 the powdered minerals include : chemical elements, o.xides, car- 

 bonates, sulphides, sulphates, and silicates. Here we have an enu- 

 meration of most of the possible ingredients of a rubber compound, 

 but the list tells little if anything about the function of each 

 ingredient in the mixture. 



PAINTS, VARNISHES AND RUBBER GOODS 



In recent years, the researches of chemists have brought to 

 light a group of drying agents which to a great extent have 

 displaced the older baking Japan driers. These are the metallic 

 soaps ; the linoleates of lead and manganese ; the resinates of 

 manganese, lead, cobalt and nickel. Tliese substances are, in 

 effect, catalytic agents which induce the rapid oxidation of the 

 oil or varnish. They form two classes of compounds, one con- 

 taining more oxygen than the other. And they easily pass from 

 one form into the other. If, for example, we have a varnish 

 containing oleo-resins, a small amount of lead resinate and some 

 oil, we will find that the lead resinate gives up half of its oxygen 

 to the oil, and then takes up more oxygen from the air. In this 

 way, the lead resinate drier acts continuously as a go-between to 



'Doctor Dannerth's conclusions are very interesting and, as a rule, sound. 

 Just why. however, an arbitrary rulintr rhoiild he made to the effect that a 

 ffiirti Cfmtainine less than 6 per cent of resin shmild he a ruhber, and one 

 fontainint; more should cnme under another dassificntion, does ^ not appe.ir 

 evident. A vahuihle cnnstitutent of any ruhber pum, be it Para rubber or 

 Pontianak, is the rubber it contains. As a rule, the resin is so much waste 

 material. It is probable, therefore, that they will all continue to he rubbers. 

 We take issue with him also, where he speaks of ielutong. "the balance 

 heintr RuUa rubber." Aclnallv. the balance is rubber, and only rubber, as 

 has been UnR established. In the writer's opinion, both guayule and 

 ielutiner. hi'int: --ubher, shotdd he classed w-ith rubbers. I^alata and chicle, 

 hein? guttas, should he classed with the guttas. — The Editor, 



