Application DMTDA PU Elastomers

   Application DMTDA PU Elastomers

   MOCA, DMTDA And TX-1 (2,4-Diamino A 5- Thiol Toluene) Three Kinds Of Chain Extender In PU Cast Elastomer Applications, Respectively, With Three Kinds Of Chain Extender To Make The Same PEA (Polycaproamide Acetic Acid Ethylene Glycol) -TDI Prepolymer Cured, Due To Their State At Normal Temperature Is Different, And Thus Different Operating Conditions. For MOCA System, Prepolymer Temperature At 80-90 ℃, MOCA Temperature At 95 -105 ℃, The Gel Time 2-3 Min; And For DMTDA And TX-1 System, The Prepolymer Temperature At 40-50 ℃, Pour Gel Time After 7-9 Min 3 个 Systems Were Uniformly Mixed, Compression Molded And Cured At 110 ℃ Under, Demold Time, Respectively:. MOCA 2-3 Min, DMTDA 4-5 Min, TX-1 2-3 Min.

    Visible, Liquid Hardener DMTDA And TX 1 Instead Of MOCA, The Mechanical Properties Of The Resulting PU Elastomers Fully Meet The Requirements Of Users.

    DMTDA Studied Kinetics And PU Prepolymer And Reactive Cz9l Our Response. The Results Showed That: The Initial Reaction Body Chain Showed A Good Relationship Between The Two Dynamics, The Latter Reaction Kinetics Influenced By Temperature. At Low Temperatures, The Reaction Is Controlled By Diffusion Effect, Second-Order Kinetic Rate Constant Becomes Smaller, And Vice Versa. In The Chain Reaction, According To The Arrhenius Equation, The Activation Energy Eu Two 26. 3 KJ / Mol, Frequency Factor A = 1. 9 X 108 Kg / (Mol · S) 0 1000C Under The Initial Reaction DMTDA Calculated The Rate Constant K?} A = 3. 7 X 10- 'Kg / (Mol · S), The Rate Constant Under The Same Conditions As MOCA KM} = 1. O1 X 10-3 Kg / (Mol · S), Described DMTDA Activity Is 3.7 Times That Of MOCA.

    I Study The Effects Of E-300 Chain Extender For PU Elastomers By Orthogonal Experimental Nature. The Results Showed That: ① Improve A NCO Content Of The Prepolymer, Elastomers Hardness, Tensile Strength And 300% Modulus Increases, And A Slight Decrease In The Elongation At Break; The Reason Is To Increase The Hard Segment Content. ② To Facilitate Cross-Linking, Generally Do Not Use A Sufficient Amount Of Chain Extender To Get In The Molecular Chain Of Diethylene Pulse Crosslinking Points. ③ Optimum Curing Time Is About 10h, 15h After Mechanical Properties Remain Basically Unchanged. ④ Gel Time Increased With An NCO Content Of Chain Extender And Shortened, With The E-300 As Chain Extender When, PPG Based Prepolymers Longest Gel Time, PTMEG Based Prepolymers Followed, PEA Group Prepolymerized It Was The Shortest.