What is Polymer?
The Basics of Polymer- Definition
& its Properties:
If
you're after basic information on plastic materials, this is
the place to find it!! Here we will tell you
about the definition and properties of polymers, the building blocks of plastics.
Plastics are polymers.
So what is a polymer?
The simplest definition of a polymer is
something made of many units. Think of a polymer as a chain. Each
link of the chain is the "-mer" or basic unit that is usually made
of carbon, hydrogen, oxygen and/or silicon. To make the chain, many
links or "-mers" are hooked or polymerized together. Polymerization
can be demonstrated by linking countless strips of construction
paper together to make paper garlands or hooking together hundreds
of paper clips to form chains, or by a string of beads.
The Structure of
Polymers:
An ordinary polyethylene film has a
molecular weight around 300,000. By way of comparison
carbon-di-oxide and water have molecular weights of 44 and 18
respectively. Due to its very high molecular weight, plastic has
high tensile strength, toughness, and percentage of elongation it is
remain in the environment for decades.
Many common classes of polymers are composed
of hydrocarbons. These polymers are specifically made of small units
bonded into long chains. Carbon makes up the backbone of the
molecule and hydrogen atoms are bonded along the backbone. There are
polymers that contain only carbon and hydrogen. Polypropylene,
polybutylene, polystyrene and polymethylpentene are examples of
these.
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Scientists and engineers are always producing better materials by
manipulating the molecular structure that affects the final polymer
produced. Manufacturers and processors introduce various fillers,
reinforcements and additives into the base polymers, expanding
product possibilities. Polymers affect every day of our life. These
materials have so many varied characteristics and applications that
their usefulness can only be measured by our imagination. Polymers
are the materials of past, present and future generations.
Degradable
Plastics:
Types of Degradable: Four different types of degradable polymers, around the
world, are in the market:-
-
Hydro degradable
polymers: Some degradable plastic products are
based on starch, and whilst non-food uses of agriculture may seem
attractive, they are not the best way forward. Some of these
plastics perforate over time but do not totally degrade, because the
starch constituent is consumed by microbial activity, but not the
plastic. The plastic residues can be harmful to the soil and to
birds and insects.
-
Aliphatic Polyester: These
products have the same disadvantage as starch they are also
expensive.
-
Photodegradable
polymers: Photodegradable polymers are
those that break down through the action of ultraviolet (UV)
light, which degrades the chemical bond or link in the polymer or
chemical structure of the plastic. This process can be assisted by
the presence of UV-sensitive additives in the polymer. They will
not therefore degrade if buried in a landfill, a compost heap, or
other dark environment, or if heavily overprinted.
-
Oxo-biodegradable
polymers: Oxo-biodegradable polymers are the most
effective and economic of the new plastics is based on
oxo-degradation and has become known as oxo-biodegradable, or
"totally degradable," A special additive is included in the
manufacturing process of conventional plastic, which changes the
behavior of the plastic. This plastic that undergo controlled
degradation through the incorporation of 'prodegradant' additives
(additives that can trigger and accelerate the degradation
process).
Oxo-biodegradable plastics are entirely
compatible with the principle of recycling and will not cause
problem in recycling. The company is pioneered in the research and
development of oxo-biodegradable plastic. Its technology is much
more superior over the earlier technologies available in other
parts of the world. The best part of this technology is that, you
don't have to change any of your machinery OR the system to
manufacture the same.
How Does this work? Please see below
video : - http://youtu.be/tQ7ce532BBM http://youtu.be/VLb1AkgW6u4 |
Comparison:
Few Advantages over
starch-based Plastics:
Oxo-biodegradable
plastics:
 Will biodegrade and no need to
bury in a compost heap or landfill in order to degrade. This is an
important factor in relation to litter, because a large amount of
plastic waste on land and at sea cannot be collected and buried.
 Can be used for direct food contact,
but will degrade as well or better.
 Will completely degrade even in the
absence of microbial activity. Governments are discouraging disposal
of organic material to landfill, so there will be fewer bacteria in
landfill pits upon which the starch-based plastics rely in order to
degrade.
 Are much cheaper to produce.
 Are thinner and use less material to
produce.
 Require less energy to manufacture
and transport.  Do not leak, and are therefore suitable for
wet waste.  Can be made transparent.  Leave no
residual plastic particles.  No danger of
genetically-modified ingredients.  Oxo Bio Degradable
Plastics is recyclable, before the degradation process
initiates.
Starch-based
plastics: Starch-based biodegradable plastics are not much
use in the fight against litter as they need to be in a microbial
environment such as a landfill or compost heap in order to
degrade.
Comparison with PAPER:
 Paper is more expensive and uses more
energy it requires to produce.
It is already one of the principal forms
of litter.
 For many uses, paper bags are
not an alternative to plastic bags. They are not durable, especially when
wet, they are not re-usable, and paper degrades less readily than oxo-biodegradable
plastic.
 Many people, especially
those on low incomes living alone, use carrier bags for the disposal
of their wet kitchen waste. Paper bags are not suitable for this
purpose.
Bags for
Life: Re-usable shopping bags are not the answer
either, because
 Those bags themselves when discarded
become a very durable form of litter because plastic re-usable
bags are made from much heavier plastic the total tonnage of
plastic discharged into the environment may even be increased,
contrary to the principle of waste minimalisation.
 The bags are much heavier and more
expensive, and a large number of them would be required to
accommodate the weekly shopping for an average family. The bags
are not hygienic if re-used without being cleansed.
 In any event shoppers do not always go to the
shop from home where the re-usable bags would normally be
kept.
Benefits:
Oxo-biodegradable
plastics:
 Have adequate tensile strength,
elongation and printable.
 Generally possess properties that
resemble low-density. Polyethylene (LDPE) or high-density polyethylene (HDPE) in overall physical properties
and theological characteristics.
 Oxo Biodegradable Plastics is recyclable, before the
degradation process initiates.
 You don't have to change any of your machinery OR the system to manufacture Oxo
Bio Degradable products.
 Films/bags can be made
in transparent too.
 It is totally degrades in to carbon dioxide, water
and bio mass. |