Ungrouped Data: When a data collection is vast, a frequency distribution table is frequently used to arrange the data. A frequency distribution table provides the...
Ungrouped Data: Know Formulas, Definition, & Applications
December 11, 2024Some 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.
Now let’s discuss 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.
The polymers derived from unsaturated hydrocarbon are called polyolefins. These include polythene, polypropene, and polystyrene.
Polythene is formed by the polymerisation of ethane.
There are two types of polythene. They are as follows:
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).
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.
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.
Polypropene is manufactured by the polymerization of propene in the presence of triethyl aluminium and titanium chloride.
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.
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.
Polyvinyl chloride (PVC), polytetrafluoroethene (VEFE), and polymonochlorotrifluoroethene (PCTFE) are three important polyhalo olefins.
Polyvinyl chloride is produced by the polymerisation of vinyl chloride using peroxide as an initiator.
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.
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.
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.
These types of polymers are produced from various types of acrylic monomers. For example, polymethyl methacrylate, Polyethylacrylate, Polyvinyl acetate, etc.
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.
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.
It is obtained by polymerising ethyl propenoate-\(2\) in the presence of traces of benzoyl peroxide.
Polyethylene acrylate is tough and has some elastic properties. It is used in the manufacture of paints, foils, flexible hoses, and for finishing fabrics.
The polymerisation of vinyl acetate in the presence of peroxide as an initiator produces polyvinylacetate.
Vinyl cyanide on polymerization in the presence of peroxide catalyst gives polyacrylonitrile.
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.
Based on the bonds between repeating units in the polymer, condensation polymers have been grouped together as polyesters, polyamides, and polyformaldehyde resins.
Polymers with ester bonds are called polyesters (poly many, ester-acid, and alcohol products). Terylene and Glyptal are polyesters.
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.
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.
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.
Glyptal is used as a binding agent like cement. This polymer is mainly used in the manufacture of paints and varnishes.
The polymer in which the amide bond is present in the chain is called polyamide. Nylon-\(6\) and nylon-\(66\) are examples of polyamides.
It is produced industrially by polymerising caprolactum in the temperature range from \(533\,{\text{k}}\) to \(543\,{\text{k}}.\) The starting material is cyclohexane.
1. Nylon-\(6\) is used in the manufacture of fibers, plastics,
It is made by condensing adipic acid and hexamethylenediamine under high pressure and high temperature.
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.
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.
It is made by dissolving urea in aqueous formaldehyde below \(283\,{\text{k}},\) and the condensation is effected by heating the mixture to \(403\,{\text{k}}{\text{.}}\)
These urea-formaldehyde resins are used in the manufacture of break-proof glass and composite panels for decorative purposes.
This polymer is prepared by heating melamine (\(2,4,\) triamino-\(1,3,5\)-triazin) with formaldehyde.
It is used for plastic crockery under the name Melmac. The cups and plates made of this polymer do not break on being dropped.
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.
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