Document 9L6wgeL02nngBx3JeXOKod54R

UNION CARBIDE INTERNAL CORRESPONDENCE Fft-EGflW CHEMICALS AND PLASTICS P. O. BOX 8361, SOUTH CHARLESTON, WEST VIRGINIA 25303 To (Nme) Mr. J. J. DlugOS, Jr. civition Building 2000-303 location Technical Center Copy to M0C Date October 31, 1968 Oriflimting Dept. Research and Development Subject Johns-Manville-61 3 Asbestos Gasket Material Dear Mr. Dlugos: You recently submitted a piece of Johns-Manville No. 61 asbestos gasketing material for evaluation and comparison with our other standard asbestos gasket products. Analysis shows the JM-61 to contain 22% of a synthetic elastomer best defined as a Buna-S. This is comparable to the binder used in Garlock 7735 or U.S. 899. Burning the material did not reveal any appreciable sulfur contained in the material. The hardness of the product was Durometer A-67 as compared with 68 for the 899 and 7735. We would consider the JM-61 to be comparable to Garlock 7735, U.S. 899, or Raybestos-Manhattan 2700. You recall that some years ago we dropped the Garlock 7021 from our list of approved gasket materials because of the natural vulcanized rubber used as the binder in the sheeting. This contained sulfur which was undesirable in certain meticulous polymerization exposures, and in general, the product did not have quite the chemical resistance of the 7735. If'there is additional information regarding this material that you wish to obtain, we will be happy to pursue the subject further. Very truly yours, LSV/bh 9526 Index: 23, 50, 112, 180, 306, 308 L. S. VanDelinder UCC 001883