Some Commercially Important Polymers: Polymers are widely used materials in today’s world and can be found in almost every material we use in our daily lives. The importance of Polymers has grown as a result of their numerous and diverse applications. To learn more about some commercially Important Polymers read this article below.

Polymers of Commercial Importance

Now let’s discuss some commercially important addition polymers:

Some Commercially Important Addition polymers

Based on the prominent functional group present in the monomer molecule, addition polymers have been divided into four main categories as polyolefins, polydienes, polyacrylates, and polyhalolefins. These are examples of chain growth polymers.

Polyolefins

The polymers derived from unsaturated hydrocarbon are called polyolefins. These include polythene, polypropene, and polystyrene.

1. Polythene

Polythene is formed by the polymerisation of ethane.

Types of Polythene

There are two types of polythene. They are as follows:

i. Low Density Polythene (LDP)

Ethene, when polymerized at a temperature of \(373\) to \(573\,{\text{k}}\) and high pressure \(\left({15000 – 45000\,{\text{pa}}} \right)\) in the presence of molecular oxygen as an initiator, gives polyethylene, which is referred to as low-density polyethylene (LDP).

Properties of Low Density of Polythene

1. Polythene is a whitish polymer.
2. It is insoluble in all solvents at room temperature.
3. Polyethylene is resistant to chemicals and, therefore, chemically inert.
4. It is a bad conductor of electricity.

Uses of Low Density Polythene

Polythene is used as an electrical insulator, anti-corrosion coating, packaging films, kitchen and laboratory utensils such as bottles, containers, and impregnating compounds for fabrics, paper and wood.

ii. High Density Polythene (HDP)

It is prepared by the polymerization of ethene in a hydrocarbon solvent in the presence of a Ziegler-Natta catalyst in the temperature range from \(333\,{\text{k}}\) to \(343\,{\text{k}}\) and under a pressure of \(600\) to \(700\,{\text{pa}}{\text{.}}\)

Properties: HDP consists of linear chains. Its density of ​is high due to the tight packing. It’s chemically inert but stronger and harder than LDP.

Uses: It is used to make garbage cans, buckets, pipes, and bottles.

2. Polypropene

Polypropene is manufactured by the polymerization of propene in the presence of triethyl aluminium and titanium chloride.

Uses of Polypropene

1. Packaging films, electrical insulation coatings, pipes, battery tanks, radio and refrigerator parts, kitchen and laboratory utensils are made from polypropylene.
2. Polypropylene fibers are superior to natural and synthetic fibers.

3. Polystyrene

Polystyrene, when polymerized in the presence of \({\text{CC}}{{\text{l}}_4},\) produces lower average molecular weight polystyrene because the growing polystyrene radical reacts with the chain transfer agent to terminate the original chain and create a new radical; the latter then initiates a new polymerisation chain.

Uses of Polystyrene

It is used for electrical insulation, in combs, plastic handles, wrapping material, foams, plastic toys, radio and television bodies, refrigerator linings, bottle caps, and other household articles.

Polyhalo olefins

Polyvinyl chloride (PVC), polytetrafluoroethene (VEFE), and polymonochlorotrifluoroethene (PCTFE) are three important polyhalo olefins.

1. Polyvinyl chloride (PVC)

Polyvinyl chloride is produced by the polymerisation of vinyl chloride using peroxide as an initiator.

Uses of Polyvinyl chloride

Polyvinylchloride is a tough, flexible material that is used in the manufacture of raincoats, handbags, tank liners, vinyl flooring, gramophone records, base pipes, and leather cloths.

2. Polytetrafluoroethene (PTFE)

Polytetrafluoroethene is produced by the addition polymerization method. When tetrafluoroethene polymerizes in the presence of benzoyl peroxide and under pressure, polytetrafluoroethene is obtained, commonly known by the initial letters PTFE. The polymer is sold by the trade name ‘Fluon’ and Teflon.

Uses of PTFE

1. Polytetrafluoroethene has remarkable properties which are leading to its usefulness.
2. The polymer is extremely resistant to heat and chemical attacks. Because of its “anti-stick” properties, it is coated with utensils used for frying and baking.
3. It is used as an electrical insulator and an excellent lubricant.

3. Polymonochlorotrifluoroethene \({\left({{\text{ClFC}} – {\text{C}}{{\text{F}}_2}} \right)_{\text{n}}}\)

It is also known as PCTFE. Its properties are similar to those of polytetrafluoroethylene. Due to the presence of \({\text{Cl}}\) atoms, this polymer is less resistant to heat and chemicals.

Polyacrylates

These types of polymers are produced from various types of acrylic monomers. For example, polymethyl methacrylate, Polyethylacrylate, Polyvinyl acetate, etc.

1. Polymethyl methylacrylate

When methyl methacrylate is heated to \(393\,{\text{k}}\) in the presence of traces of benzoyl peroxide, it polymerizes to a colorless solid by repeated addition of monomer units.

Uses of PMMA

Polymethyl methacrylate (PMMA) brands are Perspex, Lucite, and Acrylife. Its main use is as a glass substitute and as a decorative material. It is resistant to light.

2. Polyethyl acrylate

It is obtained by polymerising ethyl propenoate-\(2\) in the presence of traces of benzoyl peroxide.

Uses of Polyethylacrlate

Polyethylene acrylate is tough and has some elastic properties. It is used in the manufacture of paints, foils, flexible hoses, and for finishing fabrics.

3. Polyvinylacetate

The polymerisation of vinyl acetate in the presence of peroxide as an initiator produces polyvinylacetate.

Uses of Polyvinyl Acetate

1. The polymer is mainly used in adhesives, paints, coatings, and binders.
2. Vinylite, vinyl acetate-vinyl chloride copolymer is used in the manufacture of floor coverings and fibers.

4. Polyacrylonitrile

Vinyl cyanide on polymerization in the presence of peroxide catalyst gives polyacrylonitrile.

Uses of Polyacrylonitrile

1. The polymer is used to make Orolon fibers and Acralan.
2. The yarn spun from it is very similar to wool.

Polydienes

These are made by adding various types of monomers, at least one of which contains conjugated double bonds. Neoprene, Buna-\({\text{S,}}\) and Buna-\({\text{N}}\) are examples of polydienes.

Some Commercially Important Condensation Polymers

Based on the bonds between repeating units in the polymer, condensation polymers have been grouped together as polyesters, polyamides, and polyformaldehyde resins.

Polyesters

Polymers with ester bonds are called polyesters (poly many, ester-acid, and alcohol products). Terylene and Glyptal are polyesters.

1. Terylene (Dacron)

It is made by heating terephthalic acid with ethanediol (ethylene glycol) from \(420\,{\text{k}}\) to \(460\,{\text{k}}\) and in the presence of zinc acetate as an antimony trioxide catalyst. The two compounds condense along with the elimination of water.

Properties and Uses of Dacron

Terylene has high tensile strength and elasticity. It is hardwearing, crease-resistant, moth-proof, and rot-proof. It is used to make ropes, seat belts, tents, and sails.

2. Glyptal or Alkyd resin

This polymer is formed by the condensation of polyhydric alcohols such as ethanediol with polybasic acids or their anhydrides such as phthalic acid or phthalic anhydride.

Use of Glyptal

Glyptal is used as a binding agent like cement. This polymer is mainly used in the manufacture of paints and varnishes.

Polyamides

The polymer in which the amide bond is present in the chain is called polyamide. Nylon-\(6\) and nylon-\(66\) are examples of polyamides.

1. Nylon-\(6\)

It is produced industrially by polymerising caprolactum in the temperature range from \(533\,{\text{k}}\) to \(543\,{\text{k}}.\) The starting material is cyclohexane.

Uses of Nylon-6

1. Nylon-\(6\) is used in the manufacture of fibers, plastics,

2. Nylon-\(66\)

It is made by condensing adipic acid and hexamethylenediamine under high pressure and high temperature.

Uses of Nylon 66

1. It is a tough colorless solid and is used to make brushes, but its main uses are as synthetic fiber in stockings, shirts, sheets, parachutes, ropes, blankets and elastic stockings.

Formaldehyde Resins

This class of polymers includes Bakelite, melamine, and urea-formaldehyde resins. Formaldehyde (\({\text{HCHO}}\) – methanal) is used as a starting material in the manufacture of all of these polymers.

1. Phenol formaldehyde resins (Bakelite)

These are prepared by condensing phenol with formaldehyde in the presence of a basic catalyst. The reaction involves the formation Of methylene bridges by interlinking many phenol rings by —\({\text{CH2}}\)— groups in ortho or Ortho and para positions with respect to phenolic groups. Thus, linear and cross linked polymers can be prepared. The cross linked polymer known as Bakelite was prepared by Bakeland.

Uses of Bakelite

1. The high degree polymerisation forms a hard bakelite used for making combs and fountain pen barrels.
2. It is used for the manufacture of gears, protective coating, pieces of furniture, and electrical instrument.
3. These can be laminated with paper, leather canvas, and heated to get products with greater resistance to impact.

2. Urea formaldehyde resin

It is made by dissolving urea in aqueous formaldehyde below \(283\,{\text{k}},\) and the condensation is effected by heating the mixture to \(403\,{\text{k}}{\text{.}}\)

Uses of Urea formaldehyde resin

These urea-formaldehyde resins are used in the manufacture of break-proof glass and composite panels for decorative purposes.

3. Melamine formaldehyde resin

This polymer is prepared by heating melamine (\(2,4,\) triamino-\(1,3,5\)-triazin) with formaldehyde.

Uses of Melamine formaldehyde resin

It is used for plastic crockery under the name Melmac. The cups and plates made of this polymer do not break on being dropped.

Summary

Based on the prominent functional group present in the monomer molecule, addition polymers have been divided into four main categories as polyolefins, polydienes, polyacrylates, and polyhalolefins. Based on the bonds between repeating units in the polymer, condensation polymers have been grouped together as polyesters, polyamides, and polyformaldehyde resins. These have many applications, such as being used in electrical insulation, in combs, plastic handles, wrapping material, foams, plastic toys, radio and television bodies, refrigerator linings, bottle caps, and other household articles, etc.

FAQ’s On Some Commercially Important Polymers

Q.1. Which polymer is the most important commercially?
Ans: Polyethylene Terephthalate (PET) is the most important polymer of commercial importance.

Q.2. What are commercial polymers?
Ans: The polymers which are synthesized by chemical modification of naturally occurring polymers are known as commercial polymers. For example, PTFE, LDP, HDP, etc.

Q.3. What are 5 examples of polymers?
Ans: Five examples of polymers are Polyvinyl chloride, Nylon, polystyrene, neoprene, polyethene, and cellulose (Natural polymer).

Q.4. Which is the most important polymer?
Ans: The most important polymers are as follows:
I. Low density Polymers
II. High density Polymers
III. Polypropene
IV. Polystyrene
V. Polyvinyl chloride
VI. Polyetrafluoroethene
VII. Polymethyl methacrylate
VIII. Polyethylacrylate
IX. Dacron
X. Glyptal
XI. Nylon-\(6\)
XII. Nylon-\(66\)

Q.5. What are 4 types of polymers?
Ans: The four types of polymers are
1) Natural polymers
2) Synthetic Polymers
3) Linear polymers
4) Commercial polymers