Question

Which of the following is preferred as reagent for estimation of spin finish of synthetics in laboratory?

• A. Trichloro Acetic acid
• B. Isopropyl Alcohol
• C. Titanium Dioxide
• D. Methyl Alcohol

Hint:

• Spin finish is applied to synthetic fibers to aid processing.
• Estimation of spin finish content involves extracting the finish with a solvent.
• Suitable solvents should dissolve the finish components without affecting the fiber itself.
• Alcohols like methanol, ethanol, and isopropanol are commonly used for extracting spin finishes due to their good solvency and relative ease of handling. Isopropyl alcohol is a frequent choice.
• Other solvents like hexane or chlorinated solvents can also be used depending on the finish type.

Answer 1

The Correct Option is B

The preferred reagent for the estimation of spin finish on synthetics in the laboratory is Isopropyl Alcohol (IPA).

Explanation:

Spin finish is a lubricant applied to synthetic fibers during manufacturing to reduce friction and static. To estimate the spin finish content in the lab, a solvent is used to extract the finish from the fibers. Isopropyl Alcohol is commonly chosen because:

• It effectively dissolves most spin finish formulations.
• It evaporates quickly, leaving behind the spin finish residue for accurate measurement.
• It is relatively safe and easy to handle compared to other solvents like methyl alcohol or trichloroacetic acid.

Why not the others?

• Trichloroacetic acid: Too harsh and not typically used for spin finish extraction.
• Titanium dioxide: Not a solvent; it’s a pigment/opacifier.
• Methyl alcohol: Can be used but is more toxic than IPA and less preferred for routine lab use.

Thus, Isopropyl Alcohol (IPA) is the best choice.