Density determination of various polymer coatings

Objectives:

The purpose of this activity is to determine the density of selected coatings such as house paints, epoxies, and waxes. Density is defined as the mass per unit volume and in this activity is expressed in grams per milliliter. When this activity is completed you can compare densities of various coatingsand correlate with other physical characteristics such as hardness and adhesion.

Materials:

Prepared substrates on aluminum foil from the coatings preparationactivity and the impact tester which consists of:

• 20 mL and 1.0 mL syringes
• coating samples
• electronic balance
• paper towels

Safety:

Manufacturers provide instructions for the use of their products and these instructions should be followed completely. Protective gloves, eyewear, and lab coat should be used when handling the coatings.

Procedures:

1. Obtain a coating sample from your teacher. Record information from the label on the container.
2. Unless directed otherwise by your teacher use a 20.0 mL syringe for volume measurements.
3. You have to now find the correct volume of that syringe at the 20.0 mL mark. Discuss with your lab partner how to do this. Then get the okay from your teacher on the procedure you both develop. Use the procedures you develop to find the volume of the syringe.
4. Now that you know the exact volume of the syringe at the 20.0 mL mark you can find the density of the coating you selected. Discuss with your lab partner how to do this.
5. After obtaining teacher approval for density determination of a coating go about the process of finding the density of the coating.
6. Record all data pertinent to the activity and report your findings to the class as directed by your teacher.

Conclusions:
Obtain data from all the other lab groups in your class. Compare and contrast the class data. What conclusions can you draw from the data?