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 Polypropylene
is an economical and adaptable material that offers a
combination of exceptional bodily, chemical, mechanical,
thermal and electrical properties not found in any other
thermoplastic. Compared to low or high density polyethylene,
it has a lower impact strength, but superior operational
temperature and tensile strength.
Polypropylene bears excellent resistance to organic solvents,
degreasing agents and electrolytic attack. It has a lower
impact strength, but it's working temperatures and tensile
strength are superior to low or high density polyethylene.
It is light in weight, resistant to staining, and has a low
moisture absorption rate. This is a tough, heat-resistant,
semi-rigid material, ideal for the transfer of hot liquids
or gases. It is recommended for void systems and where
higher heats and pressures are encountered. It has excellent
resistance to acids and alkalies, but poor aromatic,
aliphatic and chlorinated solvent resistance.
Polypropylene (PP) is a linear hydrocarbon polymer. PP, like
polyethylene and polybutene (PB), is a polyolefin or
saturated polymer. Polypropylene is one of those most
versatile polymers available with applications, both as a
plastic and as a fiber, in virtually all of the plastics
end-use markets.
Polypropylene’s are available to meet the needs of various
fabrication processes such as extrusion, injection molding,
thermoforming, blow molding, biaxially oriented film (BOPP),
fiber spinning, slit tape, extrusion coating, and
laminating.
The wide range of physical properties and relative ease of
processing make polypropylene an extremely attractive
material capable of competing with more expensive resins in
a number of demanding applications.
Production of polypropylene takes place by slurry, solution or
gas phase process, in which the propylene monomer is
subjected to heat and pressure in the presence of a catalyst
system. Polymerization is achieved at relatively low
temperature and pressure and the product yielded is
translucent, but readily colored. Differences in catalyst
and production conditions can be used to alter the
properties of the plastic.
PP does not present stress-cracking problems and offers
excellent electrical and chemical resistance at higher
temperatures.
Nearly all commercial polypropylene has a level of
crystallinity intermediate between that of low density
polyethylene (LDPE) and high density polyethylene (HDPE);
its Young's modulus is also intermediate. Although it is
less tough than LDPE, it is much less brittle than HDPE.
This allows polypropylene to be used as a replacement for
engineering plastics, such as ABS.
Polypropylene has very good resistance to fatigue, so that
most plastic living hinges, such as those on flip-top
bottles, are made from this material. Very thin sheets of
polypropylene are used as a dielectric within certain high
performance pulse and low loss RF capacitors.
Polypropylene has a melting point of 320 degrees Fahrenheit
(160 degrees Celsius). Food containers made from it will not
melt in the dishwasher, and do not melt during industrial
hot filling processes. For this reason, most plastic tubs
for dairy products are polypropylene sealed with aluminium
foil (both heat-resistant materials). After the product has
cooled, the tubs are often given lids of a cheaper (and less
heat-resistant) material, such as LDPE or polystyrene. Such
containers provide a good practical example of the
difference in modulus, since the rubbery feeling of LDPE
with respect to PP of the same thickness is readily
apparent.
A rubbery PP can also be made by a specialized synthesis
process, as discussed below. Unlike traditional rubber, it
can be melted and recycled, making it a thermoplastic
elastomer.
Polypropylene or polypropene (PP) is a thermoplastic polymer,
used in a wide variety of applications, including food
packaging, textiles, laboratory equipment, loudspeakers,
automotive components, and polymer banknotes. An addition
polymer made from the monomer propylene, it is unusually
resistant to many chemical solvents, bases and acids.
The making of Polypropylene (PP) Chips is one of our principle
features. The polypropylene chips recovered and separated
during the battery breaking process and are thoroughly
washed prior to being dried for extrusion and granulation.
We also bring into being the PP Chips in virgin and master
colours for illustration Red, Blue, Yellow et cetera.
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