Document LeN5GVr40xpVoQBvxeZbKz1g

1700 S. 2nd St. TO .41* W. Touchette MONSANTO COMPANY ORGANIC CHEMICALS DIVISION ST. LOUIS, MISSOURI 63166 1760 DATE. August 12, 1971 SUBJECT: plasticizers for POLYSULFIDE SEALANTS In December 1970, we learned that Thiokol Chemical Gorp. was seriously considering a product called ZP-680 as a replacement in polysulfide sealants for Monsanto's dis continued Aroclor1254. We ran a comparison of ZP-680 against Aroclor 1254 and Santicizer 335 and Santicizer 336. It turned out that ZP-680 was incompatible. I have since been told by some customers that Thiokol is no longer promoting ZP-680. It Is good to have confirmation that our laboratory data is reliable In a case like this in which the leading experts In polysulfide technology were, for a while, apparently unaware of the deficiencies of ZP-680. One interesting situation where the change from Aroclor 1254 has produced increased customer satisfaction is Products Research, Burbank, Calif., where their Formulations Group Leader, Mel Young, indicated that Aroclor 5432 is doing a superior job for them compared to Aroclor 1254. Using stan dard formulating methods, he has had no difficulty achieving excellent viscosity control in the desired range with Aroclor 5432 and he has observed the crucial advantages' of greatly improved (reduced) volatile loss from his sealants and better adhesion to a broad range of substrates with Aroclor 5432. - Recommendations are made without guarantee, since conditions of use ore beyond our control. Nothing herein should be construed as DSW 588455 recommendations to violate patents covering any material or its use. STLCOPCB4093791 -2- The data we got on ZP-680 versus Aroclor 1254 and Santiclzers 335 and 336 were as follows: / Formulations Resin Thiokol's LP-32 Statex R Black Plasticizer 100) 30) 25) 100 Catalyst Pb 02 50) Stearic acid 5) Plasticizer 45) TOTAL 15 115 The catalyst system was given 3 passes through a paint mill and allowed to stand 120 hours before use. No separation was observed in any of the formulas. Plasticizer Property A rod oi Santicizer Santicizei 1254 ZP-680 335 * 336 Compatibility C Tacky C; C Cure Rate (4 hrs.+ OK OK OK OK Carbon Volatility # plas. lost in 24 hrs. @ 86C. 8.14 5.39 1.46 4.47 Tensile Properties # elong. at failure # Modulus, psi Ultimate Tensile Strength, psi 1270 1085 3920 1605 710 3300 1270 845 3110 5 3350 Water Sensitivity # H20 Absorbed # Soluble Matter lost 2.07 2.72 0.49 0.92 2.32 0.68 2.12 0.68 From the above data, it appears that Santiclzers 335 and 336 are more efficient flexibillzers for polysulfides thap Aro clor 1254 (100# modulus data), while Santicizer 335 Is very much less volatile and Santicizer 336 runs at about one half the -volatility of Aroclor 1254, Water sensitivities are in the same general range with a small advantage for the discontinued Aroclor 1254. I do not anticipate trouble from the water sensitivity of Santiclzers 335 and 336 as I believe they compare favorably with likely competitors in terms of this property. ^r / AWMC/gls A. W. M. Co DSW 588456 STLCOPCB4093792