Polymers & PVC
Definition of polymer
A polymer is best defined as a useful chemical made of many repeating units. Each unit is basically a “-mer”, hence many repeating units coin the term as a “Poly-mer”. It can be either a three or two or one-dimensional network of units – made up of a mix of carbon, hydrogen, oxygen, nitrogen, sulfur, chlorine, fluorine, phosphorus, and silicon. Polymers are large molecules that are comprised of thousands or in some cases millions of atoms which are bonded in a pattern that repeats itself. The atoms are bonded together as the links in a chain are. Many “-mers” are linked together or polymerized together – the best visualization can be like linking to make paper garlands of stringing beads. Polymers occur in nature and can be made as per needs. Polyethylene is an example of a material that is used to create polymers as it is used to create a wide variety of plastic bags and containers.
History of polymers
Polymers date back to the 19th century, although at the time the nature of these species was not understood. The behaviour of polymers was initially rationalised according to the theory proposed by Thomas Graham which considered them as colloidal aggregates of small molecules held together by unknown forces. The work carried out by Braconnot, Parkes, Ludersdorf and many others on natural polymers brought out the immense potential of polymers to provide innovative and cheap materials It further led to the discovery of materials such as celluloid, galalith, parkesine, rayon, vulcanised rubber and, later, Bakelite: all materials that quickly entered industrial manufacturing processes and reached households as garments components (e.g., fabrics, buttons), crockery and decorative items.
Uses of polymers.
Polymers are used in a wide applications across many industries and technologies. Polymer testing and consultancy for plastic has applications in such industries as aerospace, automotive, electronics, packaging and medical devices. Polymers are many fields of engineering from avionics through biomedical applications, drug delivery system, biosensor devices, tissue engineering, cosmetics etc. Polymer materials may include: raw materials, polymer compounds, foams, structural adhesives and composites, fillers, fibres, films, membranes, emulsions, coatings, rubbers, sealing materials, adhesive resins, solvents, inks and pigments.
Some of the uses and application of various polymeric materials and polymers themselves:
- In aircraft, aerospace, and sports equipment
- 3D printing plastics
- Organic polymers used in water purification
- Printed circuit board substrates
- Green Chemicals: Polymers and Biopolymers
- Renewable Biomass operations
- Polymers that are used in operation of bulletproof vests and fire-resistant jackets
- Electronic and photonic technologies
- Packaging and containers: films, bottles, food packaging, barrels.
- Insulation: electrical and thermal insulation, spray foams.
- Car parts: tires, bumpers, windshields, windscreen wipers, fuel tanks, car seats.
- Medical applications.
- Popular polymers for manufacturing include polyethylene and polypropylene.
Characteristics of Polymers:
- Polymers can be very resistant to chemicals.
- Polymers can be both thermal and electrical insulators.
- Generally, polymers are very light in weight with significant degrees of strength.
- Polymers can be processed in various ways.
- Polymers are materials with a seemingly limitless range of characteristics and colors.
- Polymers are usually made of petroleum, but not always.
- Polymers can be used to make items that have no alternatives from other materials.
Polymer Industry in India:
Polymers account for around 70% of petrochemicals and that is the reason that they are the most important constituent of the Indian chemical industry. Polymers form an important constituent of the Indian petrochemical industry.
Polymers are essentially used in the manufacture of various plastic products. In the consumption of the basic petrochemical, polymers form the bulk of demand with a share of around 55%.
The share of polymers in the product mix in India for various crackers ranges from 60% to 90%. The segment of polymers has registered a growth of 18% while there has been an increase of 26% in the capacities. The polymer consumption growth for 2017-2022 is 10.4%, GDP growth is 8% and import duty is 5%-0%. 11% of India’s total exports are of petroleum products.
The various byproducts of polymers are:
Polystyrene
PVC
Polypropylene
LDPE/ LLDPE
HDPE
Polypropylene is a very lightweight polymer and that is the main reason why it is used as a substitute for various other polymers. PVC has been growing at the rate of 15% yearly. Around 40% of PVC is used in the manufacturing of pipes and 14% is used in the production of cable sheathing. In India, low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE) are also widely used polymers. More than 50% of LDPE/ LLDPE is used by the packaging industry. The second most used polymer in India is HDPE, with a share of 22% is growing at the rate of 15% per year. HDPE is used in the manufacturing of raffia, blow moulding, injection moulding, and in the paper industry as well.