What is bitumen mastic?

What is bitumen matsic?

The drilling mud bentonite conform to American Petroleum Institute (API) specification 13A which yield approximately 120 to 280 barrels of 15 centiposes mud per ton, preferably about 180 to 240 barrels per ton. Typical bentonites with their trademarks are Hydraul-EZ; KWIK-THIK and Super-Gel-X. The use of non-treated bentonite in bituminous and other polymer binders is well known. The treated bentonite clay from drilling industries was discovered to be surprisingly, an excellent component in water soluble systems of bituminous mastics and sealants for cold application.

Asphalt is a bitumen derived from a number of materials such as, for example, petroleum shale oil, gilsonite and the like. Asphalt is a thick, viscous mixture of compound such as parraffinic, cycloaliphatic and aromatic hydrocarbon and lesser amounts of heterocyclic compound containing sulphur, nitrogen or oxygen. Although asphalt can be obtained from natural sources, it is primarily derived as the residue of petroleum distillation of (e.g., the bottom product of vacuum distillation is of a topped crude). Although this invention is not limited thereto, it is preferred that the asphalt have a penetration (ASTM D5) at 77 degree F., dmm: ranging from about 5 to about 300 dmm and more preferably, from about 50 to about 160 dmm and conform in general to specification outlined by ASTM D312, D946 and/or D449.

Asphalt cutback is a mixture of asphalt bitumen and petroleum solvent. Petroleum solvents can be one of the following: kerosene, fuel oils, jet fuel, mineral spirit/Stoddard, naphtha, high flash aromatic, low flash aromatic, xylene, toluene and other petroleum solvent products. For this invention the preferable asphalt cutback is a mixture of asphalt bitumen and mineral spirit/Stoddard solvent, the asphalt bitumen ranging from about 55 to 85 wt. %.

Asphalt mastic

A process of producing water reducible bituminous mastics and sealants is as follows:

1. 4% to 11% treated bentonite clay was to be added into clean water in the mixer. When clay is dispersed, or high sheared in colloid mill, after mixing it turns into clay slurry. The viscosity of clay slurry is between 20,000 to 180,000 centipoise (CPS) at 77 deg. F.

2. Asphalt bitumen cutback consists of 60 to 80 percent asphalt and 20 to 40 percent mineral spirit Stoddard solvent.

3. The clay slurry and asphalt bitumen cutback are mixed together to form a soluble system.

4. An additive is added to enhance the stability of the soluble system.

5. Non-asbestos fiber is added to reinforce the soluble system mastics and sealer film strength. It also provides additional viscosity and texture.

Included are cellulosic paper, fiberglass, mineral fiber, polymer fiber including polypropylene and polyethylene.

6. Non-reactive fillers commonly called pigment extenders are e.g. natural or calcined clay, mica and silica powder, slate powder, coal ash, fly ash, etc. are added to the system to improve film strength and product's consistency.

7. The elastomers impart buffering as well as tensile strength and elongation to the formulations and include SBR, SBS, SIBS, acrylic, styrene, neoprene, polyvinyl, etc.

EXAMPLE 1 The Preparation of Bituminous Mastic

 

   
  % By weight
   
 
  Treated bentonite clay slurry  3-60
  Asphalt Bitumen Cutback 20-90
  Fibers  2-10
  Fillers  3-15
  Additives 0.2-1.0
    100.0
   

 

This formulation is used for patching repair, roof flashing repairs and installation.

EXAMPLE 2 The Preparation of Bituminous Sealants

 

   
  % By weight
   
 
  Treated bentonite clay slurry  3-60
  Asphalt Bitumen Cutback 20-90
  Fibers 2-6
  Fillers  3-10
  Additives 0.2-1.0
    100.0
   

 

This formulation is used for recoating by brush application on foundation walls, roof, metal, wood, concrete and other building materials.

EXAMPLE 3 The Preparation of Bituminous Non-fiber Sealants

 

   
  % By weight
   
 
  Treated bentonite clay slurry  3-60
  Asphalt Bitumen Cutback 20-90
  Fillers  3-10
  Additives  .2-1.0
    100.0
   

 

This formulation has similar uses as Example 2, except for spray application.

EXAMPLE 4 The Preparation of Elastomeric Bituminous Non-fiber Mastics

 

   
  % By weight
   
 
  Treated bentonite clay slurry  3-60
  Asphalt Bitumen Cutback 20-90
  Fibers  2-10
  Fillers  3-15
  Additives 0.2-1.0
  Elastomers (Elastomeric polymers) 0.5-5  
    100.0
   

 

This lends itself to both roofing and foundation application.

EXAMPLE 5 The Preparation of Elastomeric Bituminous Sealants

 

   
  % By weight
   
 
  Treated bentonite clay slurry  3-60
  Asphalt Bitumen Cutback 20-90
  Fibers 2-6
  Fillers  3-10
  Additives 0.2-1.0
  Elastomers 0.5-3  
    100.0
   

 

EXAMPLE 6 The Preparation of Elastomeric Non-fiber Sealant

 

   
  % By weight
   
 
  Treated bentonite clay slurry  3-60
  Asphalt Bitumen Cutback 20-90
  Fillers  3-10
  Additives 0.2-1.0
  Elastomers (Elastomeric polymers) 0.5-6  
    100.0
   

 

Subject to the foregoing, the ranges and descriptions of components are about:

 

   
  % By weight
   
 
  Drilling mud bentonite  .5-11 
  Water  3-55
  Asphalt bitumen 20-90
  Cutback containing 60 to 80 wt. % asphalt and
  20-40 wt. % mineral spirit Stoddard Solvent
  Additives .2-1 
  Non Asbestos fiber  0-10
  Fillers  3-15
  Elastomer 0-8
   

 

Of course, the individual amounts are selected to provide a 100% total.

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