Document 71wK3kB9VMj9G92q3NVB96O08

r>v< 25S K i- -CT;' OI(CTO 0> tSC*C f~~j mro*TiO fT] C '**L f V.t n sec' io * 1.1 Ik 3 0l5TluTi:i BEL 0* RERORT OR(TED STATES fiTfSOM RESEARCH CEITER Vallboard TllllshcS PROGRESS REPORT L A SOB A TOk T - - flit *cewt *o. mi rmo trt*cjc:s J-1JT 3-2& 1919. 3-6-: K.B. TITLE: Asbestos Free Ready Mixed Joist Compounds Suvuab': During this report period work ms continued on the project to ellmlnaT asbestos fro* Beady Mixed Joint Coapounds. Most of the work was with kraft gel as the asbestos replaeeaant in eosbination with Attagel 40 or iocel 10,000 C?S. Atteapts vere made to alter the kraft gel to moke it aore suitable for joint coapounds. CMC-2 was also tried as an asbet replaeeaant be cam 3 of the properties it displayed when evaluated in IT dry powder Joint coapounds. . Tests shoved that by freezing or ball Billing the kraft gel improved application properties vere obtained. The ball Billing vlth steel ball broke the paper fibers down enought to give the compound a relatively smooth surface. The presence of Attagel 40 while improving the applies properties caused a large drop in viscosity thru three freeze/thav cycl Adding Kneel 10,000 CPS mokes the coapounds such more freeze/thav stabl Vltn the CMC-2, between 1.5? and 2.0% vas required to obtain good appllcation properties thus the voter requirement was high. However there was not loss in bond and the shrinkage was normal. Testing vill con tinue with these raw materials as veil as evaluating new materials or approaches for eliminating asbestos. t UNITED STAIRS GYPSUM COMPANY R23SAHCH CENTER PROGRESS REPORT Pile 3-2202 Report 19193 Date 3-6-72 Project: 3-2202 - Asbestos Free Reedy Mixed Joint Compounds JS-991 series, pages 24 6c 25, Notebook 3619 In this series kraft gel and rerf-A-Tape gel vere evaluated as asbestos replaeenents. These formulas also contained Nocel 10,000 CPS and JLttagel 40. Tests shoved that the kraft gel had better application properties than the Perf-i-Tape gel. The compounds vith the lover . 5 amount cf Eocel 10,000 CPS and Increased Attagel 40 shoved a drop v. in viscosity tnru the freeze/thav cycles. J2-992 series, pages 26 & 27, Notebook 3619 In this series different thickeners vere evaluated vith kraft gel. The best application properties vere obtained vith Methocel and _ Satrosol 250 EXP.. The VRA-31 and Cellosize ^P-100M vere very heavy applying vhile the 1 vm.:. _lso dry and gusay. Since all of these ' compounds contained Attagel 40 a big drop In viscosity vas noted thru _ the three freeze/thav cycles. J3-995 series, pages 30 4 31, Notebook 3619 __ Tvo different asbestos replacements vere evaluated In this series. Cne 1 -1 vas voci II cur end the other vas Perf-A-Tape sanding dust. The Perf-A- ~ Tape sanding dust vas evaluated as received and after grinding vith tne lab Raymond Mill. Hone cf tnese compounds applied veil and the water requirements vere low. '>00,1:)