PAC Database - Detailed Chemical Data
Chemical Identity
| Chemical | CAS# | UN# | Health Code Numbers | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Isonate 181 MDI prepolymer | z-0113 |
4.00
3.00
|
||||||||||
| Formula | Synonyms | |||||||||||
Physical Properties
| Mol Wt | State | MP (°C) | BP (°C) | VP (Hg) | VP (°C) | SG | LEL (ppm) |
|---|---|---|---|---|---|---|---|
| 0 | L | 200 |
PAC Values
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 0.15 | 5.0 | 55 |
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 0 | 0 | 0 |
Technical Basis
IsonateTM 181 MDI Prepolymer is a proprietary polyurethane product of the Dow Chemical Company®. It is composed of methylene diphenyl diisocyanate (CASRN: 26447-40-5), 4,4’-methylendiphenyl diisocyanate (MDI, CASRN: 101-68-8), and methylenediphenyl diisocyanate, dipropyleneglycol, tripropyleneglycol, copolymer (CASRN: 68092-58-0). A review of available sources identified exposure limits for methylene diphenyl diisocyante (MDI, CASRN: 101-68-8) which were evaluated for TEEL development. Data sources were selected according to the hierarchy listed in Table 3.1. The ERPG-3 and ERPG-2 were selected as TEEL-3 and TEEL-2 values, due to their use priority (Section 2.1). The TLV-TWA was selected as the TEEL-1 basis.
• TEEL-1 = TLV-TWA (MDI, CASRN: 101-68-8, 0.005 ppm/0.05 mg/m3) x 3
• TEEL-2 = ERPG-2 (MDI, CASRN: 101-68-8, 5.0 mg/m3)
• TEEL-3 = ERPG-3 (MDI, CASRN: 101-68-8, 55 mg/m3)
This review generated a TEEL-3 value consistent with Rev. 29A. The Rev. 29A and current source, an ERPG-2, is consistent; therefore, it’s unclear why the values are different. The Rev. 29A TEEL-1 was derived from the TEEL-2, while the current TEEL-1 basis is a TLV-TWA.
• TEEL-1 = TLV-TWA (MDI, CASRN: 101-68-8, 0.005 ppm/0.05 mg/m3) x 3
• TEEL-2 = ERPG-2 (MDI, CASRN: 101-68-8, 5.0 mg/m3)
• TEEL-3 = ERPG-3 (MDI, CASRN: 101-68-8, 55 mg/m3)
This review generated a TEEL-3 value consistent with Rev. 29A. The Rev. 29A and current source, an ERPG-2, is consistent; therefore, it’s unclear why the values are different. The Rev. 29A TEEL-1 was derived from the TEEL-2, while the current TEEL-1 basis is a TLV-TWA.
References
IsonateTM 181 MDI Prepolymer SDS and properties retrieved from: https://www.dow.com/en-us/pdp.isonate-181-mdi-prepolymer.3018z.html#properties
Exposure limits: https://www.osha.gov/chemicaldata/23