1. Hazards
Plastics often contain a variety of toxic additives. For example, plasticizers like adipates and phthalates are often added to brittle plastics like polyvinyl chloride (PVC) to make them pliable enough for use in food packaging, children's toys and teethers, tubing, shower curtains and other items. Traces of these chemicals can leach out of the plastic when it comes into contact with food.

2. Manufacture of Plastics
Steps:
1. Acquiring the raw material or monomer. 2. Synthesizing the basic polymer. 3. Compounding the polymer into a material that can be used for fabrication. 4. Molding or shaping the plastic into its final form.

3. Manufacture of Plastic
Raw Materials
Historically, resins derived from vegetable matter were used to produce most plastics. Today, most plastics are produced from petrochemicals which are widely available and tend to be cheaper than other raw materials. However, the global supply of oil is exhaustible, so researchers are investigating other sources of raw materials, such as coal gasification.

4. Manufacture of Plastic
Synthesis of the polymer
The first step in plastic manufacturing is polymerization. The two basic methods by which polymerization can occur are addition and condensation reactions. These can occur in the gaseous, liquid and occasionally solid phase. Sometimes the polymer synthesis can take place at the interface of two immiscible liquids in which the monomers are dissolved.

5. Manufacture of Plastic
Additives
Chemical additives can be used in the production of plastics to achieve certain characteristics. These include:
antioxidants to protect the polymer from degradation by ozone or oxygen
ultraviolet stabilizers to protect against weathering
plasticizers to increase the polymer’s flexibility
lubricants to reduce friction problems
pigments to give the plastic colour
flame retardants
antistatics

6. Manufacture of Plastic
Shaping and Finishing
Compression molding is one of the oldest methods used for converting polymers into useful materials. It uses pressure to force the plastic into a certain shape. One half of a two-piece mold is filled with plastic and then the two halves of the mold are brought together and the plastic is melted under high pressure.