Biodegradable and Non-biodegradable polymers

Biodegradable and Non-biodegradable polymers

What are Polymers?

Compounds that have molecules linked together in chains are known as polymers. Polymers offer a wide range of applications because of their unique structure.

Both synthetic and natural polymers exist. A natural polymer like rubber, for example, has excellent elasticity.

Biodegradable Polymers:

Under aerobic or anaerobic conditions, Microorganisms and enzymes break down these polymers. Some of the components that develop include cellulose, starch, and polyesters (Aliphatic polyesters). As long as they’re not damaged, they’ll retain their mechanical integrity and remain non-toxic. A few examples of biodegradable polymers include food waste, human waste and paper trash, animal dung, sewage treatment plant sludge, slaughterhouse sludge, and so on.

1. PHBV (poly-hydroxybutyrate – co-hydroxy valerate) is generated by mixing 3-hydroxy butanoic acid and 3-hydroxy pentanoic acid with an ester bond between the monomers. As it decomposes, carbon dioxide and water are released. It is brittle and can be used to manufacture medications and bottles.

2. Glycine (H2NCH2COOH) and aminocaproic acid (H2N(CH2)5COOH) polyamide polymerise to form Nylon 2–Nylon 6.

3. The condensation of hydroxybutyric acid (3-hydroxy butanoic acid) molecules produces polyhydroxy butyrate (PHB).

Non-Biodegradable Polymers:

These polymers are tough to disintegrate and add strength and durability to items. These molecules create interatomic connections and are resistant to environmental degradation; breaking the links and digesting them is difficult for microbes and enzymes. Because of this, they end up as garbage.

Glass, batteries, plastic bottles, Tetra packs, medical waste, and carbon paper are a few examples:

1. Polystyrene – Pyrolysis, which controls heat degradation without oxygen, is used to recover energy from polystyrene polymers. These polymers are tough to disintegrate and provide both solid and long-lasting commodities.

2. Polyethene: They are off three types:

i) Linear high-density polyethene (HDPE)

ii) Branched low-density polyethene (LDPE)

iii) Ultra-high molecular weight polyethylene(UHMWPE)

Harmful Effects of Biodegradable Polymers:

The environment is harmed when biodegradable wastes are released into it in large quantities. They damage the environment  in a variety of ways, including:

1. Their wastes generate a significant number of microorganisms. People, plants, and animals can all be infected with various infectious diseases caused by these bacteria.

2. An unpleasant odour is produced due to the disposal of these wastes. It generates gases that contribute to greenhouse gas emissions when it burns.

3. Infectious diseases are spread by mosquitoes and rodents, which lay their eggs in these piles of garbage.

Harmful Effects of Non-Biodegradable Polymers:

They harm the environment in various ways, including:

1. Increased use of chemical fertilisers and DDT causes the soil to become more acidic or alkaline and reduces fertility.

2. Aquatic life suffers, and algal blooms occur due to these materials being washed into nearby bodies of water. This phenomenon is known as eutrophication.

At each trophic level, toxic compounds like DDT, non-biodegradable, accumulate. Because humans are at the top of the food chain, their bodies contain most substances. That which we call “biological magnification” describes what is happening.

Conclusion:

Those polymers that degrade due to microorganisms or enzymes in aerobic or anaerobic circumstances are called biodegradable polymers. Cellulose, Starch, and polyesters are examples of materials that create them. The most common polymers of this sort are aliphatic polyesters. Examples of biodegradable polymers- Poly-hydroxybutyrate–co-hydroxy valerate (PHBV); 3-hydroxy butanoic acid, and 3-hydroxy pentanoic acid are combined to make it. Polyglycolic acid (PGA), Polyhydroxy butyrate (PHB), Polycaprolactone (PCL), Nylon-2-nylon-6 Etc.