--%>
Assignment Help - homework help

What are various structure based polymers?

This classification of polymers is based upon how the monomeric units are linked together. Based on their structure, the polymers are classified as:


1. Linear polymers: these are the polymers in which monomeric units are linked together to form long straight chains. The polymeric chains are stacked over one another to give a well packed structure. As a result of close packing, such polymers have densities, high tensile strength and high melting points. Common examples of such type of polymers are polyethylene, nylons and polyesters.

2. Branched chain polymers: in this type of polymers, the monomeric units are linked to constitute, long chains (called the main-chain). There are side chains of varied lengths which comprise branches. Branched chain polymers are irregularly packed and thus, they have low density, lower tensile strength and lower melting points as compared to linear polymers. Amylopectin and glycogen are common examples of this type.

3. Network polymers or Cross-linked: in this type of polymers, the monomeric units are linked together to constitute a three-dimensional network. The links involved are called cross-links. Cross-linked polymers are hard, rigid and brittle because of their network structure. Common examples of this type of polymers are Bakelite, melamine formaldehyde resin, etc.

 

 

   Related Questions in Chemistry

  • Q : Homework Silicon has three naturally

    Silicon has three naturally occurring isotopes. 28Si, mass = 27.976927; 29Si, mass = 28.976495; 30Si, mass = 29.973770 and 3.10% abundance. What is the abundance of 28Si?

    		•
  • Q : Explain Vapour Pressure Composition A

    A pressure composition diagram for a liquid vapor system can be used to show the composition of the liquid and equilibrium vapor.Vapor equilibrium data are useful in the study of distillations. It is of value to have diagrams showing not only the vapor pre

    		•
  • Q : Molecular weight of substance The

    The boiling point of a solution of 0.11 gm of a substance in 15 gm of ether was found to be 0.1oC higher than that of the pure ether. The molecular weight of the substance will be (Kb = 2.16)       (a) 148 &nbs

    		•
  • Q : What is heat capacity and how to

    The temperature reliance of internal energy and enthalpy depends on the heat capacities at constant volume and constant pressure. The internal energy and enthalpy of chemical systems and the energy changes that accompany chemical reactions depend on the

    		•
  • Q : Relative lowering of vapour pressure

    Which of the following solutions will have a lower vapour pressure and why? a) A 5% aqueous solution of cane sugar. b) A 5% aqueous solution of urea.

    		•
  • Q : Vapour pressure of water Give me answer

    Give me answer of this question. 5cm3 of acetone is added to 100cm3 of water, the vapour pressure of water over the solution: (a) It will be equal to the vapour pressure of pure water (b) It will be less than the vapour pressure of pure water

    		•
  • Q : Calculation of concentration of the

    Choose the right answer from following. 200ml of a solution contains 5.85 dissolved sodium chloride. The concentration of the solution will be(Na= 23: cl = 35.5 ) (a) 1 molar (b) 2 molar (c) 0.5 molar (d) 0.25 molar

    		•
  • Q : Biodegradable polymers what are the

    what are the examples of biodegradable polymers

    		•
  • Q : The three facts on the evaporation

    Describe briefly the three facts on the evaporation?

    		•
  • Q : Haloalkanes define primary secondary

    define primary secondary and tertiary alkyl halides with examples

    		•