4,4'-MDI HomopolymerCAS 25686-28-6

A specific oligomeric form of MDI used in industrial polyurethane systems — same sensitization profile as pure MDI.

Other Isocyanates substances:Toluene DiisocyanatePure MDIPolymeric MDI2,4'-MDIMDIHexamethylene DiisocyanatePolymeric TDI
Building products and consumer items containing Isocyanates family members
4,4'-MDI Homopolymer belongs to the Isocyanates family — products shown above commonly contain one or more substances from this family

Toxic Chemical Databases

Substance-specific listings — these flags are for 4,4'-MDI Homopolymer alone, not for the broader family.

LBC Red List
Listed
Prop 65
Not Listed
IARC
Listed
NTP RoC
Listed
GSPI
Not Listed
REACH SVHC
Listed
TSCA
Listed

Chemical Type

Aromatic Diisocyanate Oligomer

Chemical Description

The 4,4'-MDI homopolymer is the linear oligomer formed from repeated 4,4'-MDI units. It shows up in specialized polyurethane formulations including some adhesives and elastomers. Toxicologically it behaves essentially like pure 4,4'-MDI — a respiratory sensitizer with skin-sensitization potential, IARC Group 3 classification, and the same need to manage aerosol exposure during application.

Biological Activity

Severity scores specific to this substance, NOT the parent family average. Differences between siblings are real and meaningful.

Respiratory
10/10
Immune
9/10
Skin
8/10
Cancer
4/10
Reproductive
5/10
Developmental
5/10
Liver/Kidney
5/10
Neurological
4/10
Endocrine
3/10
Cardiovascular
3/10

Top Health Consequences

Pathways of Exposure

Building Materials with 4,4'-MDI Homopolymer

Listed alphabetically — product categories where this specific substance appears.

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