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Show Chemists Strengthen Low Grade Lumber,' Promise Profitable New Field for Farmers -Cv west, and New Jersey, Pennyslvania and New York on the east. Three and one-half million acres are considered con-sidered desirable for shelter belts." The soil conservation district program, pro-gram, under which the farmers themselves decide what lands are suitable for woodlands, today offers a practical opportunity for giving the Du Pont process a real tryout. By means of the process, wood can be made for the manufacture of doors, windows and drawers that will not swell and stick, or contract and become loose. Wood can be made strong enough to substitute for even steel in certain machinery parts. In a few days woods harder than ebony, which take a century to grow,"" can be made at small expense. Poplar becomes harder than hard maple, which in turn can be made CTWPmWJUWtJWPIJWWWJ)l'JJJJJUMUjMiJ.l.i Jil.JIJLiJIWj w sary vacuum and pressure in which the wood is placed. A steam jet ejector is an effective, simple means of producing the vacuum. The chamber cham-ber should be equipped with a pressure pres-sure door or removable head, and with a source of vacuum and of pressure. A tank for preparing the solution, an auxiliary overflow tank, and means for drying the wood are also needed. Mild steel equipment may be used. The chemicals are no more corrosive cor-rosive than water, and are neither flammable nor poisonous. To pre-i vent rusting, it is desirable to apply a waterproof finish to the exposed surfaces of the equipment. This type of equipment could be set up and operated in almost any lumber handling concern throughout the country. A chemical change takes place in the actual fibers of the wood under treatment. Methylolurea in solution enters the wood structure. In the course of drying it gradually reacts with itself and with the components of the wood, first to form insoluble but fusible products. Given sufficient time or heat, the reaction is completed com-pleted and an infusible product results. re-sults. If the wood is subjected to sufficient heat and pressure while the resin is still in the fusible stage, the resin will melt, flow and allow the wood to compress. This treatment treat-ment converts the resin to the final infusible form, maintaining the wood Treated Wood Almost Hard as Metal. By BARROW LYONS (WNU Washington Correspondent.) The alchemy of modern chemistry suddenly has prepared pre-pared a new field of profit for farmers. By the use of relatively rela-tively inexpensive equipment and by the application of certain cer-tain cheap chemicals, ordinary ordi-nary soft woods can be transformed trans-formed into material of almost al-most any desired hardness and color. Not only does this multiply the uses for which wood may be used in building and furniture manufacture, but opens possibilities for its use under conditions of pressure, humidity and moisture that formerly only metals and plastics could satisfy. Also, the decorative value of many woods can be vastly enhanced. en-hanced. And fast growing species of trees, use of which was formerly limited, can now be grown like crops to replace the slower growing varieties. vari-eties. These facts were revealed recently re-cently by Dr. J. F. T. Berliner of the ammonia department of E. I. du Pont de Nemours and company, who recently told a group of scientists and writers about the development of the chemical called methylolurea, the reagent which transforms the inner structure of wood into new substances. Tht chemicals used in this process cost only 3 cents to iVz cents per board foot treated, although the cost of equipment and labor will add to that figure in producing the new product. For the average veneer the cost of chemicals used amounts to less than two-tenths of a cent per square foot. This development assumes unusual un-usual significance in view of recent efforts of the department of agriculture agricul-ture to bring about a new realization realiza-tion of the potential importance of the woodlot to the farmer. John F. Preston, U. S. soil conservation service, estimated a few weeks ago that the income to farmers from farm woodlands could be increased to $500,000,000 a year, or more. The discovery of the Du Pont chemists may considerably raise this estimate. esti-mate. Income from Woodlot. "Farmers are interested in woodlands wood-lands not only as sources of income with which to pay taxes, buy seed, " , ' -y treatment. Methylolurea in solution ( j enters the wood structure. In the ' is "S , course of drying it gradually reacts , J1 "V K , with itself and with the components , "v " of the wood, first to form insoluble i " ' " but fusible products. Given sufficient I' I time or heat, the reaction is com- 3 ' Is , s pleted and an infusible product re- j 1. 1 ' 1 1 I suits. If the wood is subjected to A J 1 1 sufficient heat and pressure while 8y sas ( , ' , the resin is still in the fusible stage, ' ? A' i SvJ the resin will melt, flow and allow fy V.I' A' ' O J the wood to compress. This treat- k i!' ! 1 ment converts the resin to the final I1,- ,! 'I' a 1 t 3,1 infusible form, maintaining the wood sua lb" Arft"'!- l,u 1 1 1, A ' k j Impregnating apparatus in tne Du Font experimental laboratories Is rather simple. The wood is placed in the horizontal cylinder. The overhead over-head tank contains the solution of methylolurea, which flows down and impregnates the fibers of the wood. A vacuum is first created in the cylinder, then pressure. in the dimension resulting from the press. Thus, treated wood may be compressed com-pressed to produce a stable, extremely ex-tremely hard, dense product with a consolidated closed surface requiring requir-ing no filling, sanding ,or polishing. It is possible to apply moderate pressures sufficient to compress and consolidate only the surface or outer zone of the treated wood to produce a hard finish. If polished or embossed em-bossed platens are' used, these finishes can be reproduced on the surface of the wood. As far as is now known, the treatment does hot have any adverse effect on the gluing and finishing characteristics of the wood. Flame resistance is improved, and the wood is also more resistant to fungi, rot and pest infestation. in-festation. But from experiments made in Du Pont laboratories, it appears certain that a process has been developed which will give new value to the trees standing on every farm wood-lot. wood-lot. That should give an impetus to reforestation of many marginal farms, bringing back a woodland harder than the hardest tropical woods. The compressive strength of wood is so increased, and other properties imparted, that in fact a new material is created, which can be called "transmuted" wood. By this process, near-at-hand species of woods that grow on your own woodlot can be made as useful as the costlier, scarcer varieties, many of which are imported from distant lands. Won't Warp o Shrink. Furniture made from the transmuted trans-muted wood can be shipped throughout through-out the world to humid tropics or dry areas with assurance that it will not warp, swell or shrink. A built-in finish is imparted so that scratches may be removed by simply smoothing smooth-ing and rubbing. By mixing dyes with the impregnating chemicals, light-colored pine may be given the color of cherry, mahogany or ebony; or the wood may be made green, purple or any bright color throughout. Veneers sufficiently treated become be-come self-bonding, requiring no adhesive to be formed into plywoods, ply-woods, since heat and pressure fuse the product into a hard, dense substance. sub-stance. Even sawdust, shavings and similar woodwastes may be moulded into articles with dyes incorporated. Methylolurea pronounced me'th-il-ol-urea is compounded by adding add-ing urea to dimethylolurea. Both materials ma-terials are white and soluble in water. They are produced from ammonia, am-monia, carbon dioxide and methanol, meth-anol, which are synthesized from coal, air and water. Urea results from the reaction of ammonia and carbon dioxide. Formaldehyde, which is derived from methanol, condenses with urea to form dimethylolurea. These chemicals are being produced pro-duced cheaply on a large scale, but are under allocation by the war production pro-duction board. Small quantities for investigation and preliminary tests, however, can be obtained without formal allocation. After the war large quantities can be obtained. The equipment required may be quite simple. In fact, most of the apparatus now used in impregnating wood with various substances, such as creosote and flameproofing chemicals, can be adapted with minor alterations. Because of shorter treating periods, pe-riods, however, smaller scale equipment equip-ment can be used. An ingenious mechanic who understood the principles prin-ciples of the new process could rig up equipment from elements on hand in most plants, the chemists declare. Equipment Simple. All that is required is a chamber capable of withstanding the neces- Top Compressed treated wood becomes very hard and dense. The three balsa blocks in the picture were all originally the same size, but the second and third from the left have been subjected to heavy pressure. The thinnest, at the right, is now harder than any known wood, and 10 times as heavy as the original origi-nal balsa. Balsa is one of the softest soft-est and lightest woods known. Below Remarkable resistance of treated wood to warping is shown by this test, the result of which is pictured. Two strips of veneer, one treated and one untreated, were placed on wet towel. The untreated strip curled up, while the impregnated impreg-nated remained flat. shoes, clothes and put up buildings," Mr. Preston said, "but also as means of building up wood reserves re-serves to create an income balance wheel. We might call it an ever-normal ever-normal woodbin. Farm forestry has long served such a purpose in European, Euro-pean, countries. "Originally there were 913 million acres of forest land in this country, but 60 per cent of this was converted into farms, and farms now occupy fully half of the land area of the United States, The move now is to reconvert much of this cleared land to farm woodlands. "On farms today, 12,500,000 acres mostly abandoned fields and gullies gul-lies are suitable only for reforestation. refores-tation. Of this large acreage, only 15 per cent is in the south. Sixty v per cent is in the central region between Iowa and Missouri on the Treated wood doesn't swell while wet, or shrink when dry. In this test, two dowels of exactly the same diameter were fitted with brass rings that would just slip off. Then the dowels were soaked for about 24 hours. It was found that the ring on the treated dowel would slip off as easily as before, but the untreated un-treated dowel was so swollen that the ring could not be removed. cover to the soil that will conserve rainfall and lessen the danger of floods. The scientists who perfected this process say there are in the United States some fifty species of tree now used for industrial purposes, and nearly 1,000 types for which no practical prac-tical use has been found, largely because be-cause of their softness. With this new magic applied to the very soft woods, all can now be added to the resources which will help to make a victorious postwar America something some-thing like the dream which the technicians tech-nicians have envisaged. |
