MOCA
HARTCURE M (MOCA) | |
Trade Name: | MOCA |
Similar Name: | 4,4'-Methylenebis(2-chloroaniline) |
Molecular Formula: | C13H12Cl2N2 |
CAS Number: | 101-14-4 |
Hartcure M, 4,4' - Methylenebis (2-chloroaniline), also called MOCA, is a substance used as a crosslinking agent / chain extender for polyurethane products, especially for cast polyurethane elastomers (CPU). Polyurethane elastomers are flexible and posse elasticity nature like rubber but with significant properties, it combines high elasticity of rubber and rigidity of plastic. MOCA features with color stability in high temperature. MOCA-base elastomers are good for abrasion / impact / chemical / oil / ozone and cold resistance, elasticity no matter with high or low hardness (Shore A to Shore D rating), high tensile / tear / compression strength, and absorption of vibration. With the long pot life, it’s very easy to handle with, you can even handle manually instead of by machines. Resulting from those physical properties and advantages, MOCA is the most common crosslinking / chain extender for urethane elastomers (TDI system). Meanwhile, it’s also a universal curing agent for Epoxy products. At present, being the MOCA manufacturer, Johnson is the world’s largest supplier of MOCA based on the OEM cooperation with Kumiai Chemical Industry Co., Ltd. Japan.
Comparing to DETDA & DMTDA, there are some obvious advantages of MOCA as follows.
Comparing to DETDA & DMTDA, there are some obvious advantages of MOCA as follows.
- The finished product is lighter in color.
- MOCA is solid type, thus, it's much easier to store and less pollution.
- Easy to handle. Long pot life.
- Modulus is higher.
- Lower price.
The period of validity
12 months since production date.
Package
25, 50, 70 kg/fiber drum
25, 50, 70 kg/bag
It can be packaged on demand. Please inquire.
(1) Pre-heat prepolymer
- Temperature: 80℃~85℃
- Because the prepolymer is high viscous liquid or solid type, the pre-heating is necessary for workability.
- Beware: If pre-heating is last for too long, NCO content of prepolymer will be decreased, therefore, the pot life, demold time, hardness and physical properties will be changed.
(2) Degas prepolymer
- Below 30 mmHg.
- When the prepolymer is poured into the container, the degassing process is necessary because the small bubbles might cause decreasing of the physical properties of the molding goods when using.
- When processing, the quantity of prepolymer should not be over half of the container, otherwise, it might overflow during the degassing process.
- After degassing process, please keep the prepolymer at 80℃~85℃.
(3) Melt Hartcure MOCA
- The melting process is necessary due to MOCA is solid at room temperature (Melting point is 98℃).
- Melt it slowly at 110℃~120℃.
- Don’t melt MOCA twice. Thus, the properties of MOCA might be changed.
(4) Heat the mold
- Please keep the surface of mold at 100℃~110℃ after coating release agent on the mold.
- It’s better to heat the mold one day before working process.
(5) Mix prepolymer with MOCA
- Temperature: Prepolymer is at 80℃~85℃; MOCA is at 110℃~120℃
- Make sure the mixing ratio is correct, otherwise, the workability, hardness and other physical properties would be changed.
- Mix thoroughly and DON’T cause small bubbles in the solution.
(6) Cast
- Pour the solution into the mold as soon as possible after mixing. Otherwise, the viscosity will become too high to mold properly.
(7) Pre-cure and demold the mold
- Pre-cure at 100℃~110℃ in oven for 30~50 minutes before demolding.
- Beware: If the hardness of the molding product is low, increase the demolding time.
(8) Post cure
- Post-cure at 100℃~110℃ at least for 16 hours after demolding.
- The best physical properties come out after 3~7 days.
- If the hardness of the product is low, increase the post-curing time.
Trade Name | Hartcure M or MOCA |
Molecular Formula | C13H12Cl2N2 |
Molecular weight | 267.16 |
Equivalent weight | 133.58 |
Appearance | Granular (100% through 1/2-mesh sieve) |
Color | Milky white or Light yellow |
Odor | Slight amine |
Amine value | 7.4~7.6 (m.molc/g) |
Specific weight | 1.44 (solid) at 24℃ |
Specific weight | 1.26 (liquid) at 107℃ |
Melting range | 98℃~107℃ |
Storage stability
Slight moisture absorption; avoid contacting with water. Keep away from sunlight.
Solubility
Slightly soluble in water; soluble in diluted acids, ether and alcohols.
Usage
As a bridging agent between polyurethane and Epoxy resin.
As a Moca Manufacturer, MOCA is a well-known aromatic diamine chain extender or curing agent for casting polyurethane (PU) elastomers. MOCA-base elastomers have excellent properties, are widely used in various areas including construction, building, vehicles, mining, semi-conductor, epoxy, sport facility and so on.
- Bridging agent for electronic industry.
- Waterproof material / coating for construction & architectural industry.
- Chain extender for PU elastomers, i.e. jaw rubber coupling, PU spider.
- Curing agent for epoxy resin.
- Components for industrial usage, i.e. conveyor belts, casters, guide rollers, couplings.
- Shock absorption pads for automotive industry.
- Printing rollers, drum blades, squeegee blades, cleaning blades, scraper blades for printing industry.
- Sealing material.
- Epoxy insulation material.
- Antibacterial urethane sheet.
- Mineral separation screen.
- Pipe linings.