DEFINITIONS

1. Hydrophobic state and Hydrophilic state: A hydrophilic surface has a strong affinity to water and spreading of water on such a surface is preferred. Hydrophobic materials are known as non-polar
materials with a low affinity to water, which makes them water repelling⁵⁹.

2. Substrate: In chemistry, a substrate is typically the chemical species being observed in a chemical reaction, which reacts with a reagent to generate a product. It can also refer to a surface on which other chemical reactions are performed, or play a supporting role in a variety of spectroscopic and microscopic techniques⁶⁰.

3. Supercritical CO2: is a fluid state of carbon dioxide where it is held at or above its critical temperature and critical pressure. Carbon dioxide usually behaves as a gas in the air at standard temperature and pressure (STP), or as a solid called dry ice when frozen. If the temperature and pressure are both increased from STP to be at or above the critical point for carbon dioxide, it can adopt properties midway between a gas and a liquid⁶¹.

4. Cationic and Enzymatic process: Cationic polymerisation is a type of chain growth polymerisation
in which a cationic initiator transfers a proton to a monomer which then becomes reactive toward chain growth. The cationic polymerisation usually proceeds at very high rates both at high and low temperatures. Both the rate of reaction and the molecular weight decreases with increasing temperature⁶². Enzymatic process: enzymes help in accelerating the biochemical reaction which converts a substrate into a product.

5. Eutrophication: Harmful algal blooms, dead zones, and fish kills are the results of a process called eutrophication — which occurs when the environment becomes enriched with nutrients, increasing the amount of plant and algae growth to estuaries and coastal waters⁶³.

6. SALT (for dyeing process): Salt plays this crucial role of catalyst. Salt has an extremely high affinity for water. Broadly speaking, Salt is necessary in three ways, firstly, to drive dye into textile during the dyeing process in textile. Secondly, use of salt leads to maximum exhaustion of dye molecules during the dyeing process in textiles. Thirdly it is used as an electrolyte for migration, adsorption, and fixation of the dyestuff to the cellulose material⁶⁴.

7. Industry 4.0: is the information-intensive transformation of manufacturing (and related industries) in a connected environment of big data, people, processes, services, systems and IoT-enabled industrial assets with the generation, leverage and use of actionable data and information as a way and means to realise smart industry and ecosystems of industrial innovation and collaboration⁶⁵.

8. Polyethylene terephthalate (PET) is a general-purpose thermoplastic polymer which belongs to the
polyester family of polymers. Polyester resins are known for their excellent combination of properties such as mechanical, thermal, chemical resistance as well as dimensional stability. PET is one of the most recycled thermoplastic and has the number “1” as its recycling symbol. Recycled PET can be converted to fibres, fabrics, sheets for packaging and manufacturing automotive parts⁶⁶.

9. Single use plastics/polybag: Single-use plastics are goods that are made primarily from fossil
fuel–based chemicals (petrochemicals) and are meant to be disposed of right after use—often, in mere minutes. Single-use plastics are most used for packaging and service ware, such as bottles, wrappers, straws, and bags⁶⁷.

10. Biobased and biodegradable: Biobased plastics are made from renewable resources instead of non-
renewable petroleum based resources. These renewable resources can include corn, potatoes, rice, soy, sugarcane, wheat and vegetable oil. Biobased plastics are made by creating plastic polymers from these materials, through either chemical or biological processes. Examples of these types of plastics are polylactic acid (PLA) – derived from starch, polyhydroxybutyrate (PHB) – derived through microbial synthesis, and biobased polyethylene (bioPE) – produced from sugar cane. Biodegradable plastic degrades through exposure to naturally occurring microorganisms. When classifying a plastic as a biodegradable, the environment and timeframe must be specified; otherwise the claim is rendered pointless due to an array of variations. All organic matter will eventually biodegrade. This includes traditional petroleum-based plastics. However, the rate of biodegradation of different organic materials can vary on an exponential scale⁶⁸.

11. Tier 1, 2 and 3: cities include the top metropolitan cities of India. These cities are densely populated and have higher living expenses. Major international airports, industries, top multi-specialty hospitals, education, and research institutes are located in tier 1 cities. For example Bengaluru, Delhi, Mumbai, Chennai. Tier 2 cities include developing cities with a rapid growth rate in industrial and allied sectors. These cities are the most convenient destination for foreigners, especially medical travelers, to get the best services at affordable costs. For example Agra, Dehradun, Coimbatore, Lucknow. All the other cities of the country except the tier 1 and tier 2 cities come under Tier 3 category. It includes cities having lower population density and cost of living. The tier 3 cities have poor air connectivity and other infrastructure facilities⁶⁹.