--%>
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 : Organic and inorganic chemistry Write

    Write down a short note on the differences between the organic and inorganic chemistry?

    		•
  • Q : Sugar solution The solution of sugar in

    The solution of sugar in water comprises: (i) Free atoms (ii) Free ions (iii) Free molecules (iv) Free atom and molecules. Choose the right answer from the above.

    		•
  • Q : Problem on equilibrium composition The

    The catalytic dehydrogenation of 1-butene to 1,3-butadiene, C4H8(g) = C4H6(g)+H2(g) is carried out at 900 K and 1 atm.

    Q : Unit of molality Select the right

    Select the right answer of the question. The unit of molality is: (a) Mole per litre (b) Mole per kilogram (c) Per mole per litre (d) Mole litre

    		•
  • Q : F-centres If a electron is present in

    If a electron is present in place of anion in a crystal lattice, then it is termed as: (a) Frenkel defect  (b) Schottky defect  (c) Interstitial defects (d) F-centre Answer: (d) When electrons are trapped in anion vacancies, thes

    		•
  • Q : Molecular Symmetry Types The number of

    The number of molecular orbitals and molecular motions of each symmetry type can be deduced. Let us continue to use the C2v point group and the H2O molecule to illustrate how the procedure develop

    		•
  • Q : Question 6 A student was analyzing an

    A student was analyzing an unknown containing only Group IV cations. When the unknown was treated with 3M (NH4)2CO3 solution, a white precipitate formed. Because the acetic acid bottle was empty, the student used 6M HCl to dissolve the precipitate. Following the procedure of this experiment, the stu

    		•
  • Q : The three facts on the evaporation

    Describe briefly the three facts on the evaporation?

    		•
  • Q : Problem related to molarity Provide

    Provide solution of this question. Increasing the temperature of an aqueous solution will cause: (a) Decrease in molality (b) Decrease in molarity (c) Decrease in mole fraction (d) Decrease in % w/w

    		•
  • Q : Solutions The relative lowering of

    The relative lowering of vapour pressure of 0.2 molal solution in which solvent is benzene

    		•