Document qmRve3578jNeBVGjrv4Z0mzX5

i/ /:* - ' - INTERNAL CORRESPONDENCE AUG 9 1976 R N WHFfLErf JR. UC 14*- CHEMICALS AND PLASTICS TO (NAME) Mr. A. S. Anatangelo COMPANY location TAFT PLAI1T O, BOX 471, TEXAS CITY, TEXAS 7? S9-) oats August 6, 1976 .1. -asner - 501 Dr. L. T. McMaster - 31k! My. U. A. Mazzolir.i Mr. S. A. Mortirer - 501 Mr. S. M. Norwood Mr. F. S. Frovenzano Mr. K. E. Ross Dr. T. T. Szabo - 501 fir. G. r . Tacquard y Mr. R. '..'heeler - 514 slm-jlct f(VCM Content of VYDS Solvent Vinvl Resins Dear Tony: A recent review of VYDS and VYDS-66 for residual VCM indicates that a problem in measuring RVCM in these products continues to exsist. If you recall, a deterio ration in the quality of Taft-produced toluene in early 1976 made the quantifica tion of RVCM in VYDS/VYDS-66 impossible with current GC methods because of an unknown toluene impurity which had the identical retention time as vinyl chloride. Use of a higher purity Marathon-produced toluene eliminated this problem. A copy of my letter in February, 1976, regarding the problem is attached. Subtracting the contribution of the impurity from "typical" Taft-toluene from the total area normally identified as "VCM," both VYDS and VYDS-GG are meeting a 1 ppm, maximum, for RVCM. Certification of this level Ly the laboratory, using present gas chromatographic techniques, is presently impossible. The addition of a residual monomer specification of 1 ppm, max, fcr both products would be, therefore, difficult to achieve unless: 1) Change to a higher quality of toluene is made, or 2) Use of a different GC test procedure which would resolve vinyl chloride from all other interfering in-purities is made. The development of a new test procedure specifically for VYDS and VYDS-66 would be time consuming and costly. However, Dr. McMaster might be able to provide input which would help to resolve the present problems in measuring RVCM in VYDS/VYDS-G6. Please let ne know if I can assist or answer any questions regarding this matter. Very truly ycurs, /kw Attachment UQq 490g,