Collodions are liquid preparations composed of pyroxylin in solvent mixture (which solvents)?

Collodions are liquid preparations composed of pyroxylin in solvent mixture (which solvents)?

• A. Water and methanol
• B. Ethanol and acetone
• C. Methanol and ether
• D. Alcohol or ether

Answer: (D)

Collodion is a solution of nitrocellulose (pyroxylin) in a highly volatile solvent system. The solvents used are diethyl ether and alcohol (ethanol). Ether dissolves and swells the nitrocellulose, helping to lower the viscosity, while the alcohol moderates the evaporation rate and helps achieve a workable viscosity for film formation. This combination allows a smooth, even coating that dries quickly to form a thin film, which is why the solvent system is described as alcohol and ether. Other options don’t provide the essential ether–alcohol pair needed to dissolve pyroxylin effectively.

Collodion is a solution of nitrocellulose (pyroxylin) in a highly volatile solvent system. The solvents used are diethyl ether and alcohol (ethanol). Ether dissolves and swells the nitrocellulose, helping to lower the viscosity, while the alcohol moderates the evaporation rate and helps achieve a workable viscosity for film formation. This combination allows a smooth, even coating that dries quickly to form a thin film, which is why the solvent system is described as alcohol and ether. Other options don’t provide the essential ether–alcohol pair needed to dissolve pyroxylin effectively.