Application
Polypropylene (PP) as one of the five general plastics, it is widely used in daily life. Polypropylene is the lightest plastic raw material, its appearance is colorless translucent particles, as a food grade plastic, is widely used in food packaging, such as foam plastic box, PP plastic cup and so on.[4] Some common uses of polypropylene include:
1. Packaging Applications
Good barrier properties, high strength, good surface finish and low cost make Polypropylene ideal for several packaging applications.
a. Flexible Packaging: PP films’ excellent optical clarity and low moisture-vapor transmission make it suitable for use in food packaging. Other markets shrink-film overwrap, electronic industry films, graphic arts applications, disposable diaper tabs and closures, etc. PP Film is available either as Cast Film or bi-axially orientated PP (BOPP).
b. Rigid Packaging: PP is blow molded to produce crates, bottles, and pots. PP thin walled containers are commonly used for food packaging.
Figure. 1 Packaging application
2. Consumer Goods
Polypropylene is used in several household products and consumer goods applications including translucent parts, housewares, furniture, appliances, luggage, toys etc.
3. Automotive Applications
Due to its low cost, outstanding mechanical properties and moldability, polypropylene is widely used in automotive parts. Main applications include battery cases and trays, bumpers, fender liners, interior trim, instrumental panels and door trims. Other key features of automotive applications of PP include low coefficient of linear thermal expansion and specific gravity, high chemical resistance and good weatherability, processability and impact/stiffness balance.
Figure. 2 Automotive application
4. Fibers and Fabrics
A large volume of PP utilized in the market segment known as fibers and fabrics. PP fiber is utilized in a host of applications including raffia/slit-film, tape, strapping, bulk continuous filament, staple fibers, spun bond and continuous filament. PP rope and twine are very strong and moisture resistant very suitable for marine applications.
5. Medical Applications
Polypropylene is used in various medical applications due to high chemical and bacterial resistance. Also, the medical grade PP exhibits good resistance to steam sterilization. Disposable syringes is the most common medical application of polypropylene. Other applications include medical vials, diagnostic devices, petri dishes, intravenous bottles, specimen bottles, food trays, pans, pill containers, etc.
Figure.3 Medical application
6. Industrial Applications
Polypropylene sheets are widely used in industrial sector to produce acid and chemical tanks, sheets, pipes, Returnable Transport Packaging (RTP), etc. because of its properties like high tensile strength, resistance to high temperatures and corrosion resistance.
Figure.4 Industrial application
7. PP film
PP film is among the leading materials today used for flexible packaging as well as industrial applications. Two important forms of polypropylene films include:
a. Cast Polypropylene Film: Cast polypropylene commonly known as CPP and widely known for its versatility. It has super resistance to tears, greater transparency and better heat resistance at high temperatures, excellent moisture and atmospheric barriers, and high permeability to water vapor.
b. Biaxially Oriented Polypropylene Film: Biaxially oriented polypropylene film (BOPP) is stretched in both transversal and longitudinal directions, producing molecular chain orientation in two directions. This film has higher tensile strength and stiffness, good puncture and flexcrack resistance over wide range of temperatures. It also has excellent gloss and high transparency can be glossy, clear, opaque, matte or metalized and it is an efficient barrier against oxygen and moisture.