Polycarbonate has special properties which are related to its molecular structure. Before starting to list properties of polycarbonate, it is probably wise to explain why the properties are the way they are. First, the technical stuff. Take a look at the below diagram.
In it, you will see two six-sided structures. These are called phenyl groups. You will also see two groups identified by the label CH3. These are methyl groups. The presence of the phenyl groups on the molecular chain and the two methyl side groups contribute to molecular stiffness in the polycarbonate. This stiffness has a large effect on the properties of polycarbonate. First, attraction between of the phenyl groups between different molecules contributes to a lack of mobility of the individual molecules. This results in good thermal resistance but relatively high viscosity (i.e., low melt flow) during processing. The inflexibility and the lack of mobility prevent polycarbonate from developing a significant crystalline structure. This lack of crystalline structure (the amorphous nature of the polymer) allows for light transparency.
One of the biggest advantages of polycarbonate is its impact strength which is because of existence of Tgg. The following diagram compares the impact strength of polycarbonate to other commonly sold plastics.
The general properties can be summarized as follows:
- Excellent toughness
- Excellent transparency
- Excellent physical properties
- Excellent dimensional and color stability
- Very good heat resistance
- Fair chemical resistance
- Polycarbonate hollow sheets
- Polycarbonate solid sheets
- Light diffusers
- Protective shields
- Gun hit protective glasses(modified grade)