AY Honors/Plastics/Answer Key
From Pathfinder Wiki
1. Make a list of the materials and equipment used in making small castings in plastic molds.
- Plastic resin
- Catalyst
- Eye dropper (for adding the catalyst)
- Plastic disposable cup
- Craft stick (for stirring)
- A plastic mold
- An embeddable object
- Newspapers
- Goggles, gloves, and a smock (or old clothes)
- Mold release
2. Know how to clean and properly take care of plastic molds.
3. What safety precautions should be used when working with plastics?
- Go over these safety rules with your Pathfinders before opening any chemicals.
- Wear protective gear, including safety goggles, gloves, and an apron or smock.
- Read and heed all manufacturer warnings.
- Know what to do if the chemicals come into contact with a person (skin, eyes, or if ingested) before opening them.
- Use only in a well-ventilated area, preferably outside.
- Use only under adult supervision
- Do not pour resin down a drain. It may cause an expensive clog.
4. Tell how to mix resin for casting and colored layers.
5. Why are the following used?
a. Catalyst
The catalyst causes the liquid resin to undergo polymerization.
b. Surface hardener
The resin that comes into contact with the mold will cure to a hard, crystal clear finish. However, the exposed surface (i.e., the top of the mold) may not. The last layer of resin should be mixed with a surface hardening agent so that it will cure completely.
c. Pigments
Pigments are used to color the plastic to add interest to the casting.
6. What is meant by polymerization?
Polymerization is a chemical reaction in which monomers are assembled to form long chains or three-dimensional networks. In short, this is the chemical process that converts the liquid resin into the solid plastic.
