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. Polyethylene Fibered Roof Coatings and Cements While roof coatings and cements manufacturers consider their asbestos free formulations proprietary, Hercules and Minifibers, suppliers of these fibers, indicate that polyethylene fibers are used in concentrations of between 1 and 3 percent and in conjunction with clays and other fillers (Minifibers l986b; Hercules 1983). According to Hercules, a possible starting formulation for an asbestosfree roof coating includes: Asphalt cutback (65% solids) Surfactant Attapulgite clay Talc Pulpex E (R) (D-H) (Hercules 1983). Minifibers recommends a slightly different formulation for an asbestos-free roof coating containing: Asphalt cutback (65% solids) Bentonite clay Rubber (30 mesh) Calcium carbonate Mineral Spirits Short Stuff (R) Polyethylene (Minifibers 1986b). Pulpex E (R) (D-H) is recommended at increased levels as a replacement fiber in an asphalt roofing cement formulation cOntaining the following: (Hercules 1983). Asphalt cutback (65% solids) Surfactant Attapulgite clay Talc Pulpex E (R) (D-H) At least 8 manufacturers of roof coatings and cements have either partially or completely substituted asbestos with polyethylene fibers, in combination with clay and talc fillers, in their roof coatings and cements. While the raw fibers cost 3 or 4 times more than cellulose fibers on an - 11 -
equivalent basis, they are favored by manufacturers of aluminum roof coatings. Unlike cellulose fibers, polyethylene fibers do not contain water which can react with aluminum, forming a dangerous hydrogen gas, eventually resulting in the lids of containers blowing after only six months of storage (Missouri Paint & Varnish 1986). To guarantee a long shelf life many manufacturers of aluminum roof coatings such as Missouri Paint & Varnish and Columbia Paint Corporation use polyethylene fiber formulations (ICF 1986). Table 3 identifies some of the numerous manufacturers of polyethylene fibered roof coatings and cements. Missouri Paint & Varnish has discontinued asbestos processing completely in 1986 and substituted it with polyethylene fibers in combination with clay and talc fillers. They estimate that aluminum roof coatings with polyethylene fibers cost one-third more to produce than asbestos bearing counterparts (Missouri Paint & Varnish 1986). Columbia Paint Corporation estimates that the prices of the roof coatings and cements have increased over 25 percent as a result of their decision to reformulate their asbestos containing products with polyethylene fibers (Columbia Paint 1986). Manufacturers of non-asbestos roof coatings and cements whose formulations include polyethylene fibers have indicated some problems producing the formulations. a The polyethylene fiber formulations are difficult to mix requiring other ingredients such as clay and talc; a The formulations are not as strong due to the reduced tensile strength of the fibers; a The formulations cost more to produce; and, a Their long term performance is still unknown since their life on the market has been relatively short - - 5 yrs. Many current and former asbestos processors have encountered difficulties in replacing asbestos formulations with polyethylene formulations in some roofing - 12 -
Page 1 and 2: XXVII. SHEET GASKETS A. Product Des
Page 3 and 4: Table 1. Fluid and Pressure Ranges
Page 5 and 6: $20.5 million in 1985, based on an
Page 7 and 8: Table 3. Substitutes for Asbestos S
Page 9 and 10: Aramid gaskets are usually composed
Page 11 and 12: esistance. A wire insert is often a
Page 13 and 14: 6. Ceramic Fiber Mixtures Ceramic f
Page 15 and 16: REFERENCES Carborundum. 1986. Produ
Page 17 and 18: Bulk Square braád Rolled (over cor
Page 19 and 20: Table 1. Standards of Asbestos Yarn
Page 21 and 22: A. ‘I’ A. ‘-I PRESSURE ~ Movi
Page 23 and 24: Table 2. Operating Conditions and U
Page 25 and 26: Table 3. Production of Asbestos Pac
Page 27 and 28: een forced to replace the asbestos
Page 29 and 30: Table 4. Estimated Market Share for
Page 31 and 32: useful temperature limit of approxi
Page 33 and 34: 6. Other Substitute Fibers Other fi
Page 35 and 36: Table 6. Data Inputs for Asbestos R
Page 37 and 38: TSCA Section 8(a) submission. 1982.
Page 39 and 40: a viscosity control for waterproofi
Page 41 and 42: Table 1. Production of Asbestos Roo
Page 43 and 44: or talc. The additives ease grindin
Page 45 and 46: Table 2. Manufacturers of Cellulose
Page 47: Cellulose bodied roof coatings and
Page 51 and 52: compounds. These formulations have,
Page 53 and 54: . Other Roof Coatings and Cements O
Page 55 and 56: Table 4. Data Inputs for Asbestos R
Page 57 and 58: ATTACHMENT B PROJECTED PRICES ANALY
Page 59: ICF Incorporated. 1986 (July-Decemb

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