Mixed Xylene (CAS 1330-20-7) has a typical boiling range of approximately 137°C to 140°C (279°F–284°F) at atmospheric pressure. Because commercial mixed xylene is a blend of o-xylene, m-xylene, p-xylene and often trace ethylbenzene, it does not boil at a single fixed temperature like a pure compound - instead it boils across a narrow range that reflects the boiling points of its individual isomers. This boiling behavior is a key reason mixed xylene is chosen as a mid-range evaporating solvent in paints, coatings, adhesives and inks.
Boiling Points of the Individual Xylene Isomers
Mixed xylene's boiling range comes from blending isomers that each boil slightly differently. Since the isomers are close in boiling point, they behave as a fairly narrow-range solvent rather than a broad-cut mixture:
| Component | CAS No. | Boiling Point (approx.) |
|---|---|---|
| Ethylbenzene | 100-41-4 | 136.2°C |
| p-Xylene | 106-42-3 | 138.4°C |
| m-Xylene | 108-38-3 | 139.1°C |
| o-Xylene | 95-47-6 | 144.4°C |
| Commercial Mixed Xylene | 1330-20-7 | ~137–140°C (typical range) |
- Note: Exact boiling range can shift slightly depending on the isomer ratio and ethylbenzene content of a specific production batch. Always confirm with the current TDS/COA for the grade you are purchasing.
Why Boiling Point Matters for Paint and Coating Formulators
Boiling point (and the related evaporation rate) is one of the most important solvent properties for formulators because it directly affects:
- Drying speed - A solvent that boils and evaporates too quickly can cause surface defects such as blistering, pinholing or poor leveling; one that evaporates too slowly can delay production and cause sagging on vertical surfaces.
- Open time / workability - Mixed xylene's mid-range boiling point gives applicators enough working time to brush, roll or spray before the coating begins to set.
- Film formation - Controlled, gradual evaporation supports even film build and gloss development in alkyd and industrial enamel systems.
- Solvent blend design - Formulators often pair mixed xylene with faster-evaporating esters (like ethyl acetate) or slower aliphatic solvents to build a full evaporation profile from wet film to dry film.
Because mixed xylene sits in the "medium" evaporation category among common industrial solvents, it is frequently used as a base or "workhorse" solvent in solvent-based industrial paints, protective coatings, machinery finishes and alkyd-based systems. For a full overview of these applications, see what mixed xylene is used for in paints and coatings.
Boiling Point vs. Flash Point: Don't Confuse the Two
Boiling point and flash point are related but different properties. Boiling point tells you the temperature at which the liquid turns to vapor at normal atmospheric pressure - relevant to drying and distillation behavior. Flash point tells you the lowest temperature at which the solvent's vapor can ignite - relevant to storage, transport and workplace safety. Mixed xylene's flash point (approximately 27–32°C closed cup) is much lower than its boiling point, which is why it is classified as a flammable liquid even at room temperature.
How GNEE BIO Documents Boiling Range and Other Specifications
Tianjin Gnee Biotech Co., Ltd. (GNEE BIO), established in 2021, supplies Mixed Xylene (CAS 1330-20-7) in bulk to paint, coating, adhesive and ink manufacturers worldwide. Every shipment can be accompanied by:
- A Certificate of Analysis (COA) confirming batch-specific specifications
- A Technical Data Sheet (TDS) listing boiling range, density, flash point and other physical properties
- An SDS/MSDS covering safe handling, storage and transport classification
- Third-party inspection (e.g., SGS) available on request for additional quality assurance
Because boiling range and isomer ratio can vary slightly between production batches and suppliers, we recommend requesting the current TDS before finalizing your formulation, particularly if your process is sensitive to evaporation rate.
FAQ: Mixed Xylene Boiling Point
Q: Is mixed xylene's boiling point the same in every batch?
It can vary slightly depending on the isomer ratio and ethylbenzene content of that specific production batch. GNEE BIO provides a COA and TDS for each order so buyers can confirm the exact specification.
Q: Does a higher boiling point mean a slower-drying paint?
Generally, yes - solvents with higher boiling points tend to evaporate more slowly, which can extend drying time. However, actual drying speed in a finished coating also depends on resin type, film thickness, solvent blend and ambient conditions.
Q: How does mixed xylene's boiling point compare to toluene?
Toluene boils at approximately 110.6°C, noticeably lower than mixed xylene's ~137–140°C range, which is one reason toluene evaporates faster than mixed xylene in coating formulations.
For the current TDS or a bulk quotation for Mixed Xylene (CAS 1330-20-7), contact GNEE BIO.