Plastics in Packaging University at Buffalo（塑料在包装布法罗大学）.pptVIP

Plastics in Packaging What Will be Discussed Definition of a plastic. Overview of the packaging industry. Why plastics are used in packaging. A detailed look at the different types of plastics used in packaging. How plastics compare to alternative materials. Environmental Impacts What is a Plastic? A plastic is defined as an organic material that has the ability to flow into a desired shape when heat and pressure are applied and to retain that shape when they are withdrawn. Composed primarily of a binder with- Plasticizers Fillers Pigments Other additives Industry Overview World sales of primary packaging materials estimated to be $434 billion in 2001. Up 12.5% from $385 billion in 1997. World sales of finished packaging materials is estimated to be $800 billion. Four main categories of raw packaging materials: Paper and Board Glass Metal Plastic Over the past few years, plastic has become increasingly popular. Why Plastics? A wide variety of different qualities- Rigid vs. Flexible Clear vs. Opaque Lightweight Strong Cost Which Plastics are Used? Six resins account for almost 97 percent of all plastic used in packaging. Polyethylene terephthalate (PET) – 9% High-density polyethylene (HDPE) – 29% Low-density polyethylene (LDPE) – 32% Poly-vinyl chloride (PVC) – 5% Poly-propylene (PP) – 11% Polystyrene (PS) – 11% Polypropylene Physical Properties Durable High elongation 300% High Tensile Strength 4500 psi High Yield Strength 4000 psi High Melting point Low Density Lowest density of all plastics used in packaging Why Polypropylene? Practicality Inexpensive Chemically resistant Ideal for holding hot liquids Stretchy vs. rigid Many everyday uses Ketchup bottles Peanut butter jars Polyvinyl Chloride Need Title Chemically non-reactive Flexible vs. Rigid Self Extinguishing Plasticized vs. Unplasticized Plasticized is more flexible Why PVC Versatile Can be machined with standard metal working tools Self Extinguishing Used to house electrical wiring Many form