Search results
Results from the WOW.Com Content Network
A plastic bag, poly bag, or pouch is a type of container made of thin, flexible, plastic film, nonwoven fabric, or plastic textile. Plastic bags are used for containing and transporting goods such as foods, produce, powders, ice, magazines, chemicals, and waste. It is a common form of packaging.
Polyethylene was first synthesized by the German chemist Hans von Pechmann, who prepared it by accident in 1898 while investigating diazomethane. [12] [a] [13] [b] When his colleagues Eugen Bamberger and Friedrich Tschirner characterized the white, waxy substance that he had created, they recognized that it contained long −CH 2 − chains and termed it polymethylene.
Plastic bags were found to constitute a significant portion of the floating marine debris in the waters around southern Chile in a study conducted between 2002 and 2005. [29] Plastic bags don't do well in the environment, but several government studies have found them to be an environmentally friendly carryout bag option.
A 50 cent plastic bag levy was implemented on 1 April 2015 across Hong Kong. The use of plastic bags dropped 90% after the introduction of the levy. [79] Signs show that Hong Kong is phasing out the use of plastic bags at a dramatic rate. A sign proclaiming that polythene bags thinner than 30 μm are prohibited in Kasaragod, Kerala, India.
HDPE is known for its high strength-to-density ratio. [4] The density of HDPE ranges from 930 to 970 kg/m 3. [5] Although the density of HDPE is only marginally higher than that of low-density polyethylene, HDPE has little branching, giving it stronger intermolecular forces and tensile strength (38 MPa versus 21 MPa) than LDPE. [6]
Such sources of secondary microplastics include water and soda bottles, fishing nets, plastic bags, microwave containers, tea bags and tire wear. [ 69 ] [ 68 ] [ 70 ] [ 71 ] Both types are recognized to persist in the environment at high levels, particularly in aquatic and marine ecosystems , where they cause water pollution .
Expanded polyethylene copolymers (EPC) are also known - such as 50:50 (weight) materials with polystyrene. Though other properties are intermediate between the two bases, toughness for the copolymer exceeds either, with good tensile and puncture resistance. It is particularly applicable for re-usable products. [1]
In a special on CBC Television, green garbage bags (first bin bags in Canada) ranked 36th among the top 50 Canadian inventions. [3] Black plastic bags were introduced in 1950 as star sealed bags. The first bags in the United States were green and black, rather than the now-common white and clear. Flat-sealed bags first appeared in 1959.