Biodegradable Polymers: Definition, Examples, Properties and Applications

What are Biodegradable Polymers?

Polymers such as polysaccharides (starch, cellulose, etc), proteins, and nucleic acid that can disintegrate themselves in biological systems during a certain period by enzymatic hydrolysis and by oxidation, are called biodegradable polymers.

These polymers do not have a disposable problem and they do not cause pollution like their other counterpart polymers. Moreover, their availability is good and they are non-toxic. The most important class of biodegradable polymers are aliphatic polyesters are polyamides.


Examples of Biodegradable Polymers

Some common examples of biodegradable polymers are given below:

(i) Poly-b-hydroxybutyrate-co-b-hydroxyvalerate (PHBV)

Preparation-of-PHBV
It is a thermoplastic copolymer of 3-hydroxybutyric acid and 3-hydroxypentanoic acid in which two monomer units are connected by ester linkages. It is used in specialty packaging, orthopedic devices, and controlled drug release. 

For example, when a drug is enclosed in a capsule of PHBV, it is released only when the polymer is degraded in the body.

(ii) Poly(glycollic acid) Poly(lactic acid)

Preparation-of-Poly(glycollic acid)-Poly(lactic acid)

This copolymer is commercially called Dextron. This was the first biodegradable polyester used as sutures that is for stitching of wounds after an operation. This polymer gets degraded within the body in about a week. 

During this degradation, the polymer undergoes hydrolysis to form small non-toxic molecules which are excreted without causing any harm to the body.

(iii) Nylon-2-Nylon-6

Preparation-of-Nylon-2-Nylon-6

It is a biodegradable step-growth polymer. It is an alternating polyamide of glycine (containing two carbon atoms) and e-aminocaproic acid or 6-aminohexanoic acid (containing six carbon atoms).

Properties of Biodegradable Polymers

1. They are non-toxic and can be easily disposed of in nature.

2. They are capable of maintaining good mechanical stability until degraded.

3. They are capable of controlling rates of degradation.

4. They exhibit hydrophobicity that is a water-soluble enzyme that cannot easily get in contact with the polymer.


Applications of Biodegradable Polymers

1. Biodegradable Polymers like Polyactides can be used in nonwrikle fabrics, microwavable trays, food packaging, etc. It has several medical applications such as sutures, stents, and drug-delivery devices.

2. Biodegradable Polymers are also used in tissue engineering and drug delivery.

3. They are also used in wound dressings, enzyme immobilization, gene delivery, cryopreservation, and medical implant devices.

4. Biodegradable Polymers are used in soil to improve aeration and promote plant growth and health.

Popular Posts

Conducting Polymers: Definition, Examples, Properties and Applications

Image
What are Conducting Polymers? As the name suggests organic polymers that conduct electricity are known as conducting polymers. They are also known as intrinsically conducting polymers (ICPs) and they have alternating single and double bonds along the polymer backbone (conjugated bonds) or that are composed of aromatic rings such as Phenylene, naphthalene, anthracene, pyrrole, and thiophene which are connected through carbon-carbon single bonds. Examples: Polyacetylene, Polypyrrole, Polyaniline, etc What is the reason behind conducting nature of these polymers? Conducting polymers comes in two forms that are doped conducting polymers and non-doped conducting polymers. The conductivity of non-doped conjugated polymers is due to the existence of a conductivity band similar to a metal. In a conjugated polymer, three of the four valence electrons form strong sigma bonds through sp² hybridization where electrons are strongly localized. The remaining unpaired electron of each carbon atom re
Read more

Crime Scene: Definition, Types and Characteristics

Image
What is a Crime Scene ? A place where the crime is committed or where the maximum physical evidence related to crime is found is known as a crime scene. A crime scene is a starting point of the investigation which provides information about the suspect and the victim. This helps to reconstruct the crime and fast resolution of the case. It is noted that the crime scene is not limited to a single place but may extend to a wider area depending upon the nature of the crime committed. For example, In a murder case where murder is done at one place and the body is disposed on another place. In this case, we have two crime scenes that give information about the crime. Types of Crime Scene Based on evidence found on the crime scene: 1. Primary Crime Scene The crime scene where the actual crime occurred or where more usable pieces of evidence were found is known as the primary crime scene. For example, A murder scene, theft, assault, etc. 2. Secondary Crime Scene The crime scene which is some
Read more

Documentation of the Crime Scene: Step by Step

Image
What is documentation of the crime scene and Why it is done? After securing the crime scene, the next most important step is documentation of the crime scene because documentation permanently records the crime scene and its physical evidence. Documentation should be done without any wastage of time as the scene and its evidence may get altered over time. The documentation should be done innovatively and the originality of the crime scene should be maintained and documentation should not have pauses or breaks, it should remain constant till the whole crime scene is documented. There are four main tasks of documentation that is note-making, photography, videography , and sketching . It should be noted that all four tasks are necessary and none is a substitute for another. For example, notes are not substitutes for photography, video is not a substitute for sketching, etc. Following are the sequence for crime scene documentation: 1. Note making Documentation of crime scene in the f
Read more