| 配方类型： |
ADHESIVES |
| 配方说明： |
Urethane Caulking Compounds (Two-Can System) |
| 配方组成： |
"Polycin" 53/-
"Atomite"/155
Tributyl Phosphate/5
VM&P Naphtha/6
Tributyl Phosphate/55
"Atomite"/400
A: "Polycin" U-56 Prepolymer/100
Colloidal Silica/20
Colloidal Silica ("Syloid" 244)/10
B: DB Castor Oil/150
VM&P Naphtha/30
"Polycin" U-63 Prepolymer/-
"Polycin" 52/- |
| 配制方法： |
In each instance, the "Atomite" is first incorporated with the "Polycin" U prepolymer (A) and with the DB Oil or "Polycin" curing polyol (B), using an efficient mixer. Addition of solvent (VM&P naphtha), plasticizer (tributyl phosphate), and antislump agent (colloidal silica) is then made in that order.
For best shelf life, the "Atomite" and other materials should be thoroughly dried before use, since the reactive-NCO groups of the prepolymer component react with any contaminating moisture.
Recent work indicates that improved physical properties can be obtained by completely eliminating the solvent and plasticizer from the calk formulation. The following are typical sealants formulated at a 100% solids content. Note that a reduced filler content is necessary to maintain a satisfactory consistency which in turn makes these upgraded calks somewhat more expensive on a weight basis. |
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