Generate your Abstract and line of thought using the following keywords:
Polymers: thermoplastics (polypropylene), thermosets; manufacturing processes: plastic injection molding; Characterization: thermal, mechanical, physicochemical

Discuss the following topics in correct language and organized flow of ideas within your introduction:
1. Differences in manufacturing processes between various polymeric classes (thermoplastics/thermosets)
2. Other processes for thermoplastics manufacturing: difference between injection & extrusion.
3. Brief explanation of a plastic injection system.
4. Advantages and limitations of injection molding.

The introduction should be followed with "Material" section, containing the following properties:
-Chemical Name, Trade Name, Wt. % of U.S. Plastic Sales(*), Bulk List Price $/Ib (*), Type of Plastic, Density, Tensile Strength, Young's Modulus (E), Impact Strength: Izod, Elongation % , Hardness, Dielectric Strength, Max. Service Temperature (no load), Melting Point, Glass Transition Temperature
(Properties marked with (*) are not necessary).
-Repeated unit
-General properties of the polymer: advantages and limitations
-Typical applications

The section has to include a complete description of the device used (injection molding machine), explaining the following:
1. Detailed explanation of the plastic injection machine system: extruder, heating system, plunger, cooling and ejector systems.
2. Differences in extruder shape for crystalline versus amorphous polymers, linked to thermoplastics phase diagram(s).
3. Injection molding procedures.
4. Process parameters that need to be adjusted.

1. Mechanical Testing: tension test to measure the tensile strength, and impact test to measure the impact strength (toughness).
2. Flammability Testing: Molten material form, flame color, burning fashion, smoke
3. Physical Testing: dimensions, density and physical shape
4. Chemical Testing: effect of chemical attack by different chemicals, depicting changes in weight when immersed in:
-Strong alkali (NaOH)
-Weak acid (HCl (dilute))
-Strong acid (HCl (conc))
-With Water

Discuss the agreement or disagreement of the experimental results with the tabulated data for the used polymers, and those obtained in the experiment.
Also, generally comment on the injection molding process.

--The following sites and books contain useful information and images for several articles that we have encountered in this experiment. Make sure to check them.

MatWeb

Kalpakjian, Serope. Manufacturing Process for Engineering Materials. Addison Wesley, 3^rd Ed., 1997.

Smith, William F. . Principles of Materials Science and Engineering. McGraw Hill, 3^rd Ed., 1996.