Introduction to Common Methods for Measuring Oil Content in Fibers

The oil content in chemical fibers refers to the dry weight of the oiling agent as a percentage of the total dry weight of the fiber. The oiling rate, on the other hand, refers to the dry weight of the oiling agent relative to the fiber’s weight after degreasing. Oil content plays a key role in the spinnability of fibers. Low oil content can lead to static buildup, while excessive oil may cause stickiness or fiber tangling—both of which negatively impact textile processing. Therefore, the amount of oiling agent used should be minimized, provided that antistatic and lubrication requirements are met. Common methods for oil content measurement include solvent extraction, as well as quicker alternatives like compression and gravimetric methods.

Typical Oil Content in Synthetic Fibers

Commonly Used Industrial Testing Methods:

 

Solvent Extraction: This method takes advantage of the oiling agent’s solubility in organic solvents. A Soxhlet extractor is used to remove non-fibrous substances from the fiber surface. The solvent is then evaporated, leaving behind non-volatile oil. The oil content is calculated based on the mass of the fiber and extracted oil.

Neutral Soap Solution Washing: This method relies on the affinity between neutral soap solution and the oil on drawn textured yarn (DTY). Under the action of detergent, oil is removed from the fiber, and the oil content is calculated based on the weight difference before and after washing.

Nuclear Magnetic Resonance (NMR): In this method, the sample is exposed to pulsed magnetic fields. When the field is removed, the sample emits electromagnetic signals that decay over time. Since signals from fiber decay faster than those from oil, the difference can be used to calculate oil content through calibration and data conversion.

National Standard Method for Fiber Oil Content Testing

Recommended Instrument:
PQ001-Fiber | NMR Analyzer for Fiber Oil Content