6.1 Plastics Components
161
Irganox 1010, BPA, Cyanox 2246) and (TNPP, Irgafos 168) as the first group and
second group, respectively [5, 6].
(6) Slip agents
Slip agents or lubricants are added to the plastics to reduce the surface coefficient
of friction of a polymer, smoothen the plastics surface, enhance the mold release,
improve the anti-sticking properties and reduce the melt viscosity. The most common
lubricants are fatty acid amides (primary erucamide and oleamide), fatty acid esters,
metallic stearates and waxes [3, 6].
In addition to the materials mentioned above, other additives such as colorant
(pigment), hardener or curing agent, foaming agent, etc., may be added to the plastics
based on the product requirements [3].
6.2 Plastics Classification
Same as resins as discussed in the above Section, plastics are also classified into
thermoplastics and thermosets. Thermoplastics are made from the thermoplastic
resin and thermosets from the thermoset resins. The two plastics categories are further
subdivided into six groups as follows [4, 8]:
(1) Polyethylene Terephthalate (PET): commonly used for food packaging, bottles
of water, shampoos, cleaning sprays, tennis balls. This type of plastic is the most
recyclable type and can be disposed of in curbside bins.
(2) High-Density Polyethylene (HDPE): commonly used in toys, fuel tanks, folding
chairs and tables, milk jugs, plastic crates, natural gas pipes, etc. It is the most
widely produced synthetic plastic polymer and has the advantages of being
lightweight and strong. This type of plastic is also easily recyclable and can be
disposed of in curbside bins.
(3) Polyvinyl Chloride (PVC): mostly used in construction, flooring, window
frames, healthcare, food wrap, etc. It is a popular alternative to metal pipes
as it is resistant to corrosion. However, it is not readily recyclable and may not
be collected in the recycling bins in some municipalities.
(4) Low-Density Polyethylene (LDPE): mostly used in food applications such as
produce bags, sandwich bags, squeezable bottles, etc. The LDPE bags cannot
be collected at the curbside recycling bins and they have to be removed manually
at the receiving section of the material recovery facilities (MRFs) as they tend to
jam up the sorting equipment. However, the hard LDPE items such as squeezable
bottles can be collected at the curbside recycling bins if they are thoroughly
cleaned.
(5) Polypropylene (PP): commonly used for making straws, plastic diapers,
beverage cups, bottle caps, disposable plates, prescription bottles, etc. This type
of plastic may be disposed of in curbside bins in some municipalities.
161
Irganox 1010, BPA, Cyanox 2246) and (TNPP, Irgafos 168) as the first group and
second group, respectively [5, 6].
(6) Slip agents
Slip agents or lubricants are added to the plastics to reduce the surface coefficient
of friction of a polymer, smoothen the plastics surface, enhance the mold release,
improve the anti-sticking properties and reduce the melt viscosity. The most common
lubricants are fatty acid amides (primary erucamide and oleamide), fatty acid esters,
metallic stearates and waxes [3, 6].
In addition to the materials mentioned above, other additives such as colorant
(pigment), hardener or curing agent, foaming agent, etc., may be added to the plastics
based on the product requirements [3].
6.2 Plastics Classification
Same as resins as discussed in the above Section, plastics are also classified into
thermoplastics and thermosets. Thermoplastics are made from the thermoplastic
resin and thermosets from the thermoset resins. The two plastics categories are further
subdivided into six groups as follows [4, 8]:
(1) Polyethylene Terephthalate (PET): commonly used for food packaging, bottles
of water, shampoos, cleaning sprays, tennis balls. This type of plastic is the most
recyclable type and can be disposed of in curbside bins.
(2) High-Density Polyethylene (HDPE): commonly used in toys, fuel tanks, folding
chairs and tables, milk jugs, plastic crates, natural gas pipes, etc. It is the most
widely produced synthetic plastic polymer and has the advantages of being
lightweight and strong. This type of plastic is also easily recyclable and can be
disposed of in curbside bins.
(3) Polyvinyl Chloride (PVC): mostly used in construction, flooring, window
frames, healthcare, food wrap, etc. It is a popular alternative to metal pipes
as it is resistant to corrosion. However, it is not readily recyclable and may not
be collected in the recycling bins in some municipalities.
(4) Low-Density Polyethylene (LDPE): mostly used in food applications such as
produce bags, sandwich bags, squeezable bottles, etc. The LDPE bags cannot
be collected at the curbside recycling bins and they have to be removed manually
at the receiving section of the material recovery facilities (MRFs) as they tend to
jam up the sorting equipment. However, the hard LDPE items such as squeezable
bottles can be collected at the curbside recycling bins if they are thoroughly
cleaned.
(5) Polypropylene (PP): commonly used for making straws, plastic diapers,
beverage cups, bottle caps, disposable plates, prescription bottles, etc. This type
of plastic may be disposed of in curbside bins in some municipalities.