α-Methyl Styrene Dimer
NOFMER® MSD is a suitable Chain Transfer Agent (CTA) for polymers containing styrene such as PS, AS polymers or SB latexes. In addition, NOFMER®MSD can be used as an addition agent with functions of a crosslinking co-agent and a retarder for LDPE crosslinking.
Because of these features, NOFMER®MSD is used in the production of coating materials, high–voltage electric cables and others.
"2,4-diphenyl-4-methyl-1-pentene" is a main component in NOFMER® MSD. The chemical structure is as follows.
(α-Methyl Styrene Dimer)
(CAS Registry No: 6362-80-7)
|Specific Gravity||0.992 (20 ˚C)|
|Viscosity||18.0 cps (20 ˚C)|
|Flash point 150 ˚C||150 ˚C|
① NOFMER® MSD works as a CTA for PS, ASpolymers or SB latexes, etc.
② NOFMER® MSD works as a crosslinking co-agent and a retarder for LDPEcrosslinking (XLPE).
③ NOFMER® MSD has less odor compared tomercaptans or other retarders (BHT etc).
NOFMER® MSD is used in the production of coating materials as a CTA or covering of high–voltage electric cables as a crosslinking co-agent and a retarder.
In the point of view of the chain transfer constant,NOFMER® MSD is a suitable CTA because an excellent transfer constant should be between 0.01 and 1.0.
Furthermore, NOFMER® MSD can control lowmolecular weight andmolecular weight distribution than NDM.
In addition, NOFMER® MSD can reduce molecular weight with increasing dosage, while keeping molecularweight distribution.
Table. Chain transfer constant (Ctr)
|Chain transfer constant||Ctr at 60˚C Monomer|
Table. Polymerization of styrene
|CTA||Mw × 10⁻⁴||Mw/Mn|
|NOFMER® MSD||0.5 wt%||11.1||2.8|
|n-dodecylmercaptan (NDM)||0.5 wt%||25.3||6.8|
NOFMER® MSD can make a highly crosslinked polymer as a crosslinking co-agent at crosslinking temperature (180˚C). In addition, NOFMER® MSD can prevent scorch effectively as a retarder at kneading temperature (145˚C). NOFMER® MSD haswell balanced results in both torque value and scorch time.
Fig. Time-torque curve for LDPEcrosslinking
Table. Comparison data of NOFMER® MSD with other additives
|Type||Amount (phr)||Max. torque(N.m)(180˚C)||Scorch time˟˟ (min) (145˚C)|
*TAIC: Triallyl isocyanurate, TMPT; Trimethylolpropane trimethacrylate
˟˟Scorch time: Time to reach 10% of Max. torque at scorch-test temp (145˚C).
◆ Package style: Drum
◆ Quantity: 200KG(440 lb)
◆ Drum size: Φ585 × 890 mm (Φ23.0 × 35.0 in)
◆ Transportation Info: Class 9,UN3082, PGIII