--%>
Assignment Help - homework help

What are biodegradable polymers? Present some examples.

 

These are polymers that can be broken into small segments by enzyme-catalysed reactions. The required enzymes are produced by microorganism. It is a known fact that the carbon-carbon bonds of chain growth polymers are inert to enzyme-catalysed reactions, and hence they are non biodegradable. To make such polymers biodegradable we have to insert certain bonds in the chains so that these can be easily broken by the enzymes. Now when such polymers are buried as waste, microorganisms present in the ground can degrade the polymer.

One of the most excellent methods of making a polymer biodegradable is by introducing hydrolysable ester group into the polymer.

For example if acetal is added to an alkene undergoing radical polymerisation, ester group will be inserted into the polymer.

The weak links in the polymer are susceptible to enzyme catalysed hydrolysis.

Aliphatic polyesters are one of the significant categories of biodegradable polymers. Some other examples of biodegradable polymers are described below:

(i) PHBV (Poly-hydroxybutrate-co- 856_Biodegradable1.png-hydroxy valerate):  it is a copolymer of 3-hydroxy butyric acid and 3-hydroxypentanoic acid.
378_Biodegradable.png 


PHBV is used in orthopaedic devices and controlled drug release. The drug put in PHBV capsule is released after this polymer is degraded by enzymatic action. It can also be degraded by bacterial action.

(ii) Poly glycolic acid and poly lactic acid: these are also biodegradable polymers and are used for post operative stitches. These are bioabsorbable structures.

(iii) Nylon-2-Nylon: it is an alternating polyamide copolymer of glycine2233_Biodegradable3.png  and amino caproic acid1005_Biodegradable4.png and is biodegradable.

907_Biodegradable2.png

 

 

 

 

 

   Related Questions in Chemistry

  • Q : Importance of organic chemistry

    Describe the importance of organic chemistry?

    		•
  • Q : Finding strength of HCL solution Can

    Can someone please help me in getting through this problem. 1.0 gm of pure calcium carbonate was found to require 50 ml of dilute  HCL for complete reaction. The strength of the HCL  solution is given by: (a) 4 N  (b) 2 N  (c) 0.4 N  (d) 0.2 N

    		•
  • Q : Describe chemical properties of amines.

    Like ammonia, primary, secondary and tertiary amines have a single pair of electrons on N atom. Hence chemical behavior of amines is similar to ammonia. Amines are basic in nature, and in most of the reactions they act as nucleophiles.      1. Reaction wi

    		•
  • Q : DNA Organic Explain DNA organic in

    Explain DNA organic in brief?

    		•
  • Q : Problem based on normality Choose the

    Choose the right answer from following. NaClO solution reacts with H2SO3 as,. NaClO + H2SO3→NaCl+ H2SO4. A solution of NaClO utilized in the above reaction contained 15g of NaClO per litre. The

    		•
  • Q : How molecule-molecule collisions takes

    An extension of the kinetic molecular theory of gases recognizes that molecules have an appreciable size and deals with molecule-molecule collisions. We begin studies of elementary reactions by investigating the collisions b

    		•
  • Q : Problem on thermodynamic equilibrium In

    In the manufacture of sulphuric acid by the contact process, S02 is oxidized to SO3 over a vanadium catalyst: The reactor is adiabatic and operates at atmospheric pressure. The gases enter the reactor at 410&d

    		•
  • Q : Equimolar solutions Select the right

    Select the right answer of the question. Equimolar solutions in the same solvent have : (a)Same boiling point but different freezing point (b) Same freezing point but different boiling poin (c)Same boiling and same freezing points (d) Different boiling and differe

    		•
  • Q : The Liver Is Responsible For Much Of

    The Liver Is Responsible For Much Of The Pentose Phosphate Activity Explain

    		•
  • Q : How can enzymes act as catalyst?

    Enzymes are complex proteinous substances, produced by living bodies, such as act as catalysis in the physiological reactions. The enzymes are, also called biochemical catalysts and the phenomenon is known as bio-chemical catalysis because numerous reactions that occur the bodies of animals and p

    		•