FAQs
What are plastics?
What are the main characteristics of polyethylene?
What are the different types of polyethylene
What are the basic properties of polyethylene
What are the common additives that are added to PE in the manufacturing stage?
To what extent can plastics be recycled?
What are plastics?
Plastics are organic macro molecules (polymers) of high molecular weight which can be given desired shape and size by applying heat and pressure. Polymer is a substance made of many units containing carbon atoms which makes up the backbone of the molecule and hydrogen atoms are bonded along the backbone. A polymer by definition is poly (many) mer (parts). Polymer is like a chain that is made of a string of beads. Each link of the chain is the "-mer" or basic unit that is usually made of carbon, hydrogen, oxygen and/or silicon. Polyethylene, polypropylene, polybutylene, polystyrene are some examples of these.
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What are the main characteristics of polyethylene?
A: General characteristics of polyethylene can be summarized as -
- Light weight
- Broad-service temperature
- Excellent process ability
- High-impact strength
- Excellent chemical resistance
- Excellent weather ability
- Soft and stiff(depending on density)
- Taste free, odor free and toxic free applicable to food CONTACT applications.
- Excellent heat seal ability
- Good heat stability
- Low permeability of water.
- Excellent low temperature properties
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What are the different types of polyethylene
A:
What are the basic properties of polyethylene
A:
- MFI: Melt flow index indicates melt fluidity of a resin.It represents the rate of extrusion of resin from an extrusion plastometer in gms/10 min at 190 degree C and under a load of 2.16 kg through an orifice of 2.09 mm inner diameter. Increase or decreases of MFI may affect processing variables and end product performance.
- Density: Density which is mass per unit volume is used to measure crystallinity of the polymer. Increase or decreases of density also affects processing parameters and end product performance.
- Molecular weight distribution: It is the relative index which shows the distribution of polymers with different molecular weight around the average molecular weight . It also influences processing parameters to the same extent as the MFI and Density.
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What are the common additives that are added to PE in the manufacturing stage?
A:
- Antioxidant: -To prevent degradation of polymer during
- processing
- storage
- end usage.
- Slip : To reduce interlayer coefficient of friction (C.O.F) of the polymer film when it is required to slide over another polymeric or metallic substance like in Form Fill and Seal machine (FFS) used in packaging;
- Antiblock: To improve openability of the film.
- Polymer Processing Aid (PPA) :
- to improve the surface finish (reduce melt fracture)
- to improve the output
- to improve the process ability
- reduces the motor load
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To what extent can plastics be recycled?
A: Recycling of post-user plastics is successfully practiced where a large, homogeneous stream of plastics waste is available. Plastic bottles are an example of a good post-user waste stream suitable for recycling. In principle all thermo plastics can be recycled, but in actual practice the overall recycling level achieved appears at first sight to be rather low. It is - and always has been - a common practice in the manufacturing of plastics products for offcuts from the moulding operations to be fully recycled back into the process.
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