The best substitute for Moca/DMTDA - L300 (LIQUID)

Key feature

● Appearance: amber liquid

● Good replacement for MOCA

● Non toxic to human being

● No need to preheat

● Eco-friendly

Application

PU coatings, architectural coatings, sports materials, epoxy insulation material, waterproof wall and waterproof 

roofing materials.  Printing rollers, rollers, trolley wheels and molds of PU elastomers. 

Introduction

MOCA is used as PU (Polyurethane Resin) curing agent. The chlorine atoms on benzene ring can slow down the activity of "NH2" group, so as to extend the pot life while casting.

Structural Formula
Physical Properties of MOCA-L300 Curative

Equivalent Weight

107

Appearance

Amber Liquid

Odor

Slight Amin

Boiling Point,()

667(353)(decomposes)

Density(g/cm3) @

68(20)

1.21

 

140(60)

1.18

212(100)

1.15

Viscosity , Cps @

68(20)

690

 

140(60)

22

212(100)

5

Vapor Pressure, mm @65(20)

0.6

Amine Number, mg.KOH/g

536

TDA content %, by weight

1.0%

Moisture

0.1%

Processing
MOCA-L300, being a liquid at room temperature result in significant processing advantages, for example, in such operation as transfer, melting down of solids is eliminated. Also, the possibility of freezing-up is no longer a concern during mixing or in meter mixing machines. Additionally, its liquid state permits processing prepolymer at lower temperatures than that of MOCA. MOCA-L300 has an equivalent weight of 107 compared to 133.5 for MOCA. This means that about 20% less by weight is required for a given prepolymer at the same stoichiometry.
Example
Prepolymer (% NCO 4.1)
100Pts
100Pts
MOCA @ 95% Theory
12.4Pts
-
MOCA-L300 @ 95% Theory
-
9.9Pts
Formula Weight
112.4Pts
109.9Pts

 

The specific gravity of MOCA-L300 is about 1.2g/cm3 at recommended use temperatures of 70-90(21-33) ,whereas the specific gravity of molten MOCA at its use temperature of molten MOCA at its use temperature of 240(116) is 1.26. This means that weight delivery by volumetric pimps is comparable for the two materials and therefore if no alterations for meter-mixing machines, we must change the formula weight of MOCA into that of MOCA-L300.

Physical Properties of Prepolymer Cured With MOCA-L300 Curative

The physical properties of prepolymer, both ether and ester types, when cured with MOCA-L300 curative, are comparable to those obtained with MOCA. As in MOCA-curing system, physical properties are sensitive to the ration (stoichiomety) of curative to prepolymer. MOCA-L300 curative exhibition tolerance to stoichiomety variations similar to that of MOCA.


Low stoichiomety (80~90%) generally tends to maximize properties such as compression set resistance, while high stoichiomety (100-105%) tends to maximize properties such as tear strength and flex life. The best results for most application are obtained at about 95% stoichiometry. While cure conditions (temperature and times) are similar to those used with MOCA, MOCA-L300 curative requires somewhat closer attention to post cure conditions to obtain maximum physical properties, particularly with respect to compression set and dynamic properties. Use the recommended schedules listed.

Package
20kg per iron drum

200kg per iron drum


Notice: These values are based on the test of our present laboratory test specimens.